The Commission has received a submission from William M. Hannay, Attorney at Law, Counsel for Safety Glazing Certification Council (“petitioner”), dated June 26, 2012, requesting that the Commission initiate a rulemaking to replace the current testing procedures for glazing materials codified at 16 CFR 1201.4, with those contained in ANSI Z97.1, “American National Standard for Safety Glazing Materials Used in Building—Safety Performance Specifications and Methods of Test.” The Commission is docketing this request as a petition under the Consumer Product Safety Act (CPSA). 15 U.S.C. 2056 and 2058. The current standard for architectural glazing materials applies to glazing materials used or intended to be used in the architectural products subject to the standard, i.e., storm doors or combination doors, doors, bathtub doors and enclosures, shower doors and enclosures and sliding glass doors. The testing procedures set forth in Section 1201.4 require impact tests and accelerated environment durability tests which are intended to determine if glazing materials used in these architectural products meet safety requirements designed to reduce or eliminate unreasonable risks of death or serious injury to consumers when glazing material is broken by human contact. The testing procedures further describe the testing equipment and apparatus required to be used, and the test result interpretation methodology to be employed in determining if the glazing materials being tested meet the safety requirements of the standard.

Petitioner asserts that consumers and the glazing industry would be better served by replacing the test procedures for glazing materials used in the above-referenced architectural products in 16 CFR 1201.4 with ANSI Z97.1's purportedly more efficient and more modern procedures. Petitioner notes that the testing procedures set forth in Section 1201.4 were promulgated in 1977 and have not been updated or clarified since their original adoption by the Commission. Petitioner points out that the ANSI standard for glazing materials has been updated periodically (in 1984, 1994, 2004 and 2009) since the mandatory standard was promulgated, and that these updates include modifications in testing equipment and procedures that provide better protection for consumers.

Petitioner asserts that the absence of updates to the mandatory standard during a period in which the ANSI standard was revised four times has resulted in different testing methods and qualifying procedures that has created confusion in the industry regarding which test methodology must be used in what circumstance. Petitioner claims that the existence of overlapping but divergent mandatory and voluntary standards has created confusion for manufacturers in determining which standard applies, and resulted in manufacturers being required to pay for dual qualification testing, because different specifying agencies reference one or both standards. Petitioner also includes the proposed language that would replace the current Section 1201.4, directing manufacturers and private labelers of glazing material to test and certify the compliance of their products to the current ANSI standard.

By this notice, we seek comments concerning this petition. Interested parties may obtain a copy of the petition by writing or calling the Office of the Secretary, U.S. Consumer Product Safety Commission, Room 820, 4330East-West Highway, Bethesda, MD 20814; telephone (301) 504-7923. A copy of the petition is also available athttp://www.regulations.gov, under Docket No. CPSC-2012-0049, Supporting and Related Materials.

For detailed information regarding this proposal, EPA prepared a Technical Support Document (TSD). The TSD can be viewed athttp://www.regulations.gov.

The following table of contents describes the format of this notice:

EPA is proposing to determine that the New York-N. New Jersey-Long Island, NY-NJ-CT PM2.5nonattainment area, referred to from this point forward as the NY-NJ-CT PM2.5nonattainment area, has attained the 2006 24-hour PM2.5NAAQS. This proposed determination is based upon quality-assured, quality-controlled, and certified ambient air monitoring data that show that the area has monitored attainment of the 2006 24-hour PM2.5NAAQS for the 2007-2009 and 2008-2010 monitoring periods and continues to attain through 2011. The New York portion of the NY-NJ-CT PM2.5 nonattainment area contains the counties of Bronx, Kings, Nassau, New York, Orange, Queens, Richmond, Rockland, Suffolk, and Westchester. The New Jersey portion of the NY-NJ-CT PM2.5nonattainment area contains the counties of Bergen, Essex, Hudson, Mercer, Middlesex, Monmouth, Morris, Passaic, Somerset, and Union. The Connecticut portion of the NY-NJ-CT PM2.5nonattainment area includes the counties of Fairfield and New Haven.

EPA received requests from the States of Connecticut, New Jersey, and New York (States) for the determination of attainment for the 2006 24-hour PM2.5NY-NJ-CT PM2.5nonattainment area. The States submitted air monitoring data, design value trends, and summaries of PM2.5emissions control programs. The information provided by the States supports the proposed determination being made by EPA that the NY-NJ-CT PM2.5nonattainment area has attained and continues to attain the 2006 24-hour PM2.5NAAQS. Copies of the information submitted by the States are available in the TSD.

The proposed determination, if finalized, under the provisions of EPA's PM2.5implementation rule (see 40 CFR 51.1004(c) and further reaffirmed in the implementation guidance for the 2006 24-hour PM2.5. NAAQS)1 would: (1) Suspend the requirements for the NY-NJ-CT PM2.5nonattainment area to submit an attainment demonstration, reasonably available control measures, reasonable further progress plan, and contingency measures related to the attainment of the 2006 24-hour PM2.5NAAQS; (2) continue until such time, if any, that EPA subsequently determines that the area has violated the 2006 24-hour PM2.5NAAQS; (3) be separate from the designation determination or requirements for the NY-NJ-CT PM2.5nonattainment area based on the 1997 annual PM2.5NAAQS; and (4) remain in effect regardless of EPA's designation of this area as a nonattainment area for purposes of the 1997 annual PM2.5NAAQS. Furthermore, as described below, any such final determination would not be equivalent to the redesignation of the area to attainment based on the 2006 24-hour NAAQS.

If this rulemaking is finalized and EPA subsequently determines, after notice-and-comment rulemaking in theFederal Register,that the area has violated the 2006 24-hour PM2.5NAAQS, the basis for the suspension of the specific requirements, set forth at 40 CFR 51.1004(c), would no longer exist, and the area would thereafter have to address the pertinent requirements.

The determination that EPA proposes with thisFederal Registeraction, that the air quality data shows attainment of the 2006 24-hour PM2.5NAAQS, is not equivalent to the redesignation of the area to attainment. This proposed action, if finalized, would not constitute a redesignation to attainment under section 107(d)(3) of the Clean Air Act (CAA), because we would not yet have approved a maintenance plan for the area as required under section 175A of the CAA, nor a determination that the area has met the other requirements for redesignation. The designation status of the area would remain nonattainment for the 2006 24-hour PM2.5NAAQS until such time as EPA determines that it meets the CAA requirements for redesignation to attainment.

This proposed action, if finalized, is limited to a determination that the NY-NJ-CT PM2.5nonattainment area has attained the 2006 24-hour PM2.5NAAQS. The 2006 24-hour PM2.5NAAQS became effective on December 18, 2006 (71 FR 61144, October 17, 2006) and is set forth at 40 CFR 50.13. Effective December 14, 2009, EPA made designation determinations, as required by CAA section 107(d)(1), for the 2006 24-hour PM2.5NAAQS (74 FR 58688, November 13, 2009). EPA's proposed rulemaking action here addresses only the 2006 24-hour PM2.5NAAQS, and has no bearing on any other NAAQS, including any future revised NAAQS. EPA's proposed rulemaking action in this notice is restricted to EPA's determination that the NY-NJ-CT PM2.5nonattainment area is attaining the 2006 24-hour PM2.5.This proposed action has no effect on control measures, or air quality, in the area.

If this proposed determination is made final and the NY-NJ-CT PM2.5nonattainment area continues to monitor attainment of the 2006 24-hour PM2.5NAAQS, the requirements for the area to submit attainment demonstrations, reasonably available control measures, reasonable further progress plans, and contingency measures related to attainment of the 2006 24-hour PM2.5NAAQS would remain suspended.

On September 21, 2006, EPA established a 24-hour PM2.5NAAQS at 35.0 micrograms per cubic meter (µg/m3) based on a 3-year average of the 98th percentile of 24-hour concentrations and retained the annual PM2.5NAAQS at 15.0 µg/m3based on a 3-year average of the annual mean (71 FR 61144). EPA established the standards based on significant evidence and numerous health studies demonstrating that serious health effects are associated with exposures to particulate matter. The process for designating areas following promulgation of a new or revised NAAQS is contained in section 107(d)(1) of the CAA. EPA and state air quality agencies initiated the monitoring process for the PM2.5NAAQS in 1999, and deployed all air quality monitors by January 2001. On November 13, 2009, (74 FR 58688), EPA published its air quality designations with respect to the 2006 24-hour PM2.5NAAQS based upon air quality monitoring data from those monitors for calendar years 2006-2008. These designations became effective on December 14, 2009. The NY-NJ-CT PM2.5area was designated as nonattainment for the 2006 24-hour PM2.5NAAQS. This proposed determination addresses the 2006 24-hour standard only.

On November 15, 2010 (75 FR 69589), EPA made the determination that the NY-NJ-CT PM2.5nonattainment area attained the 1997 annual PM2.5NAAQS. On April 25, 2007 (72 FR 20586), EPA promulgated its implementation rule to assist states and tribes with the development of State Implementation Plans (SIPs) to demonstrate attainment of the annual and 24-hour 1997 PM2.5NAAQS, codified at 40 CFR part 51, subpart Z. This rule, at 40 CFR 51.1004(c), specifies some of the regulatory consequences of a determination of attainment of the standard.

On March 2, 2012, EPA provided implementation guidance for the 2006 24-hour PM2.5NAAQS. The 2012 guidance reaffirms and continues to use the framework and policy approaches of the April 25, 2007 rule. The 2006 24-hour PM2.5NAAQS implementation guidance includes additional guidance for states in developing their SIPs.

EPA has reviewed the ambient air monitoring data for PM2.5, consistent with the requirements contained in 40 CFR part 50 and recorded in the EPA Air Quality System database for the NY-NJ-CT PM2.5nonattainment area from 2006 through the present time. On the basis of that review, EPA has concluded that this area has attained the 2006 24-hour PM2.5NAAQS based on data for the 2007-2009 and 2008-2010monitoring periods and continues to show attainment through 2011.

Under EPA regulations at 40 CFR 50.13(c): The 24-hour primary and secondary PM2.5standards are met when the 98th percentile 24-hour concentration, as determined in accordance with 40 CFR part 50, Appendix N, is less than or equal to 35.0 µg/m3.

Table 1 shows the design values by county (i.e.,the 3-year average of 98th percentile 24-hour PM2.5concentrations) for the 2006 24-hour PM2.5NAAQS for the NY-NJ-CT PM2.5nonattainment area monitors for the years 2006 through 2010 based on complete (except where otherwise noted), quality-assured and certified air quality monitoring data. As shown in Table 1, none of the design values for the periods of 2007-2009 and 2008-2010 in the NY-NJ-CT PM2.5nonattainment area exceed the 2006 24-hour PM2.5NAAQS of 35.0 µg/m3. Table 1 also provides certified, complete, and quality assured 98th percentile 24-hour concentrations for 2011 which show continued attainment of the 24-hour PM2.5NAAQS.

EPA's reviewof monitoring data indicates that, for the periods of 2007-2009 and 2008-2010 and 2011, the NY-NJ-CT PM2.5nonattainment area has met, and continues to meet, the 2006 24-hour PM2.5NAAQS. EPA is soliciting public comments on the issues discussed in this document. These comments will be considered before taking final action.

Data handling conventions and computations necessary for determining whether areas have met the PM2.5NAAQS, including requirements for data completeness, are listed in Appendix N of 40 CFR part 50. A year meets data completeness requirements when at least 75 percent of the scheduled sampling days for each quarter have valid data. The use of less than complete data is subject to the approval of EPA, which may consider factors such as monitoring site closures/relocation, monitoring diligence, and nearby concentrations in determining whether to use such data as set forth at 40 CFR part 50, Appendix N, section 4.1(c). Five monitors in the NY-NJ-CT PM2.5nonattainment area with less than complete data were examined to determine if the monitors would have attained the 24-hour PM2.5NAAQS hadthey collected complete data. EPA had previously addressed less than complete data in the determination of attainment for the NY-NJ-CT PM2.5nonattainment area for the 1997 annual standard NAAQS (see 75 FR 45076, 45079 (August 2, 2010), 75 FR 69589 (November 15, 2010)). The same statistical based method used to examine less than complete data for the 1997 annual PM2.5NAAQS was used for this action regarding the 2006 24-hour PM2.5NAAQS.

The statistical method used addressed less than complete data by determining if a monitor would have been in attainment of the NAAQS had it operated to completeness from 2007-2009 and 2008-2010. The approach summarized in this section, and further described in the TSD, may or may not be appropriate for other areas with less than complete data. EPA will determine the appropriateness of this analytical approach for each area with less than complete data on a case-by-case basis. In this case, EPA has determined that it is appropriate to use this statistical method for the NY-NJ-CT PM2.5nonattainment area due to the adequateness of the monitoring network in the nonattainment area, historical air quality trends, and valid explanations for completeness issues.

EPA determined the adequacy of the monitoring network by examining the number and placement of monitors located in the nonattainment area through annual monitoring reviews and approval of network plans. The NY-NJ-CT PM2.5nonattainment area is required to have 3 monitors and the nonattainment area had 42 in 2009. The States of New York, New Jersey, and Connecticut meet annually with EPA to discuss issues or concerns with air monitoring, data, and network. The three states also have approved network plans. Copies of the approved annual network review letters are available in the TSD.

The method used to determine the design value for monitors with incomplete data involves establishing a linear relationship between incomplete monitors and another site in the NY-NJ-CT PM2.5nonattainment area that has more complete data for the missing period and has a substantial number of samples in common over the period of interest. The same method was used for each incomplete monitor that had previously violated the NAAQS. The monitor in the nonattainment area that had complete data and had the highest correlation with an incomplete monitor was used to develop a regression equation. The regression equation was used to estimate values for the missing quarters of data for an incomplete monitor. The design value for each incomplete monitor was then calculated using the estimated values to fill in for the missing quarters. The estimated design value was then analyzed using a bootstrapping statistical method. Bootstrapping involves the use of regression residuals and repeating the regression analysis 1000 times. There were no exceedances of the NAAQS as a result of the bootstrapping analysis.

The result of the analysis determined that the design value for 5 monitoring sites that: (1) Had incomplete monitoring data during 2006-2008, 2007-2009, and/or 2008-2010, (2) had previously violated the 2006 annual PM2.5NAAQS, and (3) did not have clean data subsequent to their latest violation, would be below the 2006 24-hour PM2.5NAAQS of 35.0 µg/m3if they had operated the entire monitoring time period. The 5 previously incomplete sites in the NY-NJ-CT PM2.5nonattainment area were: Newark-Willis Center in Essex County, NJ; Elizabeth Lab in Union County, NJ (only incomplete for 2007-2009); and PS 59, Canal Street, and PS 19, in New York County, NY. The detailed statistical analysis performed to obtain the completed design values for these monitors can be found in the TSD.

EPA is proposing to determine that the NY-NJ-CT PM2.5nonattainment area for the 2006 24-hour PM2.5NAAQS has attained the 2006 24-hour PM2.5NAAQS for the 2007-2009 and 2008-2010 monitoring periods and continues to attain the standard based on data through 2011. As provided in 40 CFR 51.1004(c), if EPA finalizes this determination, it would suspend the requirements for this area to submit attainment demonstrations, reasonably available control measures, reasonable further progress plans, and contingency measures related to attainment of the 2006 24-hour PM2.5NAAQS so long as the area continues to attain the 2006 24-hour PM2.5NAAQS.

This action proposes to make a determination based on air quality data, and would, if finalized, result in the suspension of certain Federal requirements. For that reason, this proposed action:

Is not a significant regulatory action subject to review by the Office of Management and Budget under Executive Order 12866 (58 FR 51735, October 4, 1993);

Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501et seq.);

Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601et seq.);

Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);

Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);

Is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);

Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001);

Is not subject to requirements of Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the CAA; and

Does not provide EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).

In addition, this rule does not have Tribal implications, as specified by Executive Order 13175 (65 FR 67249, November 9, 2000), because the SIP is not approved to apply in Indian country located in the State, and EPA notes that it will not impose substantial direct costs on Tribal governments or preempt Tribal law.

In the Final Rules section of thisFederal Register, EPA is approving the State's SIP submittal as a direct final rule without prior proposal because the Agency views this as a noncontroversial submittal and anticipates no adverse comments. A detailed rationale for the approval is set forth in the direct final rule. If no adverse comments are received in response to this rule, no further activity is contemplated. If EPA receives adverse comments, the direct final rule will be withdrawn and all public comments received will be addressed in a subsequent final rule based on this proposed rule. EPA will not institute a second comment period. Any parties interested in commenting on this action should do so at this time. Please note that if EPA receives adverse comment on an amendment, paragraph, or section of this rule and if that provision may be severed from the remainder of the rule, EPA may adopt as final those provisions of the rule that are not the subject of an adverse comment. For additional information, see the direct final rule which is located in the Rules section of thisFederal Register.

On September 4, 1992, EPA promulgated 40 CFR part 55,1 which established requirements to control air pollution from OCS sources in order to attain and maintain federal and state ambient air quality standards and to comply with the provisions of part C of title I of the Act. Part 55 applies to all OCS sources offshore of the States except those located in the Gulf of Mexico west of 87.5 degrees longitude. Section 328 of the Act requires that for such sources located within 25 miles of a State's seaward boundary, the requirements shall be the same as would be applicable if the sources were located in the COA. Because the OCS requirements are based on onshore requirements, and onshore requirements may change, section 328(a)(1) requires that EPA update the OCS requirements as necessary to maintain consistency with onshore requirements.

Pursuant to section 55.12 of the OCS rule, consistency reviews will occur (1) At least annually; (2) upon receipt of a Notice of Intent under section 55.4; or (3) when a state or local agency submits a rule to EPA to be considered for incorporation by reference in part 55. This proposed action is being taken in response to the submittal of requirements by the Santa Barbara County APCD. Public comments received in writing within 30 days of publication of this document will be considered by EPA before publishing a final rule.

Section 328(a) of the Act requires that EPA establish requirements to control air pollution from OCS sources located within 25 miles of States' seaward boundaries that are the same as onshore requirements. To comply with this statutory mandate, EPA must incorporate applicable onshore rules into part 55 as they exist onshore. This limits EPA's flexibility in deciding which requirements will be incorporated into part 55 and prevents EPA from making substantive changes to the requirements it incorporates. As a result, EPA may be incorporating rules into part 55 that do not conform to all of EPA's state implementation plan (SIP) guidance or certain requirements of the Act. Consistency updates may result in the inclusion of state or local rules or regulations into part 55, even though the same rules may ultimately be disapproved for inclusion as part of the SIP. Inclusion in the OCS rule does not imply that a rule meets the requirements of the Act for SIP approval, nor does it imply that the rule will be approved by EPA for inclusion in the SIP.

In updating 40 CFR part 55, EPA reviewed the rules submitted for inclusion in part 55 to ensure that they are rationally related to the attainment or maintenance of federal or state ambient air quality standards or part C of title I of the Act, that they are not designed expressly to prevent exploration and development of the OCS and that they are applicable to OCS sources. 40 CFR 55.1. EPA has also evaluated the rules to ensure they are not arbitrary or capricious. 40 CFR 55.12(e). EPA has excluded rules that regulate toxics, which are not related to the attainment and maintenance of federal and state ambient air quality standards.

EPA is soliciting public comments on the issues discussed in this document or on other relevant matters. EPA will consider these comments before taking final action. Interested parties may participate in the Federal rulemaking procedure by submitting written comments to the EPA Region IX Office listed in theADDRESSESsection of thisFederal Register.

1. After review of the requirements submitted by the Santa Barbara County APCD against the criteria set forth above and in 40 CFR part 55, EPA is proposing to make the following District requirements applicable to OCS sources. Earlier versions of these District rules are currently implemented on the OCS:

The District also submitted the following new rule which is not currently in effect on the OCS, for incorporation into Part 55. We are proposing to incorporate this rule into part 55:

Under the Clean Air Act, the Administrator is required to establish requirements to control air pollution from OCS sources located within 25 miles of States' seaward boundaries that are the same as onshore air control requirements. To comply with this statutory mandate, EPA must incorporate applicable onshore rules into part 55 as they exist onshore. 42 U.S.C. 7627(a)(1); 40 CFR 55.12. Thus, in promulgating OCS consistency updates, EPA's role is to maintain consistency between OCS regulations and the regulations of onshore areas, provided that they meet the criteria ofthe Clean Air Act. Accordingly, this action simply proposes to update the existing OCS requirements to make them consistent with requirements onshore, without the exercise of any policy discretion by EPA. For that reason, this proposed action:

• Is not a “significant regulatory action” subject to review by the Office of Management and Budget under Executive Order 12866 (58 FR 51735, October 4, 1993);

• Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601et seq.);

• Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);

• Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);

• Is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);

• Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001);

• Is not subject to requirements of Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the Clean Air Act; and

• Does not provide EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).

In addition, this proposed rule does not have tribal implications as specified by Executive Order 13175 (65 FR 67249, November 9, 2000), because it does not have a substantial direct effect on one or more Indian tribes, on the relationship between the Federal Government and Indian tribes, or on the distribution of power and responsibilities between the Federal Government and Indian tribes, nor does it impose substantial direct compliance costs on tribal governments, nor preempt tribal law.

Under the provisions of the Paperwork Reduction Act, 44 U.S.C. 3501et seq.,an agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB control number. OMB has approved the information collection requirements contained in 40 CFR part 55 and, by extension, this update to the rules, and has assigned OMB control number 2060-0249. Notice of OMB's approval of EPA Information Collection Request (“ICR”) No. 1601.07 was published in theFederal Registeron February 17, 2009 (74 FR 7432). The approval expires January 31, 2012. As EPA previously indicated (70 FR 65897-65898 (November 1, 2005)), the annual public reporting and recordkeeping burden for collection of information under 40 CFR part 55 is estimated to average 549 hours per response, using the definition of burden provided in 44 U.S.C. 3502(2).

Title 40 of the Code of Federal Regulations, Part 55, is proposed to be amended as follows:

To participate in the in-person meeting, you must register in advance no later than 5 p.m., Eastern Time (ET) on September 17, 2012, by contacting Junie Percy of IntelliTech by email tojunie.percy@itsysteminc.comor by phone at (937) 427-4148 ext. 210. Seating for the public is limited and will be available on a first-come, first-served basis for those persons registered.

To participate in the webcast, you must register in advance at the following Web address:https://www3.gotomeeting.com/register/369407742.The number of connections available for the webcast is limited and will be available on a first-come, first-served basis.

During the meeting and webcast, there will be a segment for public questions and input. EPA encourages public input and will allocate time to receive verbal statements on a first-come, first-serve basis. Participants will be provided with a set time frame for their statements. To ensure adequate time for public input, individuals or organizations interested in presenting an oral statement should notify Junie Percy by email atjunie.percy@itsysteminc.comno later than 5 p.m., ET on September 17, 2012.

Special Accommodations:To request special accommodations for individuals with disabilities, please contact Junie Percy at (937) 427-4148 ext. 210 or by email tojunie.percy@itsysteminc.com.Please allow at least five business days prior to the meeting to allow time to process your request.

This is a summary of the Commission's Fourth Further Notice of Proposed Rulemaking, DA 12-1343, released on August 17, 2012. The document is available for download athttp://fjallfoss.fcc.gov/edocs_public/.The complete text may also be purchased from the Commission's copy contractor, Best Copy and Printing, Inc., Portals II, 445 12th Street SW., Room CY-B402, Washington, DC 20554, telephone 1-800-378-3160, or via email tofcc@bcpiweb.com.

1. In a July 2004 Report and Order, the Commission reconfigured the 800 MHz band to eliminate interference to public safety and other land mobile communication systems operating in the band, 69 FR 67823, November 22, 2004. However, the Commission deferred consideration of band reconfiguration plans for the border areas, noting that “implementing the band plan in areas of the United States bordering Mexico and Canada will require modifications to international agreements for use of the 800 MHz band in the border areas.” The Commission stated that “the details of the border plans will be determined in our ongoing discussions with the Mexican and Canadian governments.”

2. In a Second Memorandum Opinion and Order, adopted in May 2007, the Commission delegated authority to Public Safety and Homeland Security Bureau to propose and adopt border area band plans once agreements are reached with Canada and Mexico, 72 FR 39756, July 20, 2007. Specifically, the Commission noted that “once those discussions are completed, and any necessary modifications to our international agreements have been made, we will need to amend our rules to implement the agreements and identify the portions of the 800 MHz band that will be available to U.S. licensees on a primary basis. In addition, we will need to adopt a band plan for the border regions that specifies the ESMR and non-ESMR portions of the band and the distribution of channels to public safety, B/ILT, and SMR licensees.”

3. On June 8, 2012, the United States and Mexico signed an agreement modifying the international apportionment of 800 MHz spectrum in the U.S.-Mexico border region, which enables the U.S. to proceed with 800 MHz band reconfiguration along the U.S.-Mexico border. In the Fourth Further Notice of Proposed Rulemaking, the Public Safety and Homeland Security Bureau, on delegated authority, seeks comment on proposals for establishing and implementing reconfigured 800 MHz channel plans along the U.S.-Mexico border.

4. Pursuant to §§ 1.415 and 1.419 of the Commission's rules, 47 CFR 1.415, 1.419, interested parties may file comments and reply comments on or before the dates indicated on the first page of this document. All filings related to thisFourth Further Notice of Proposed Rulemaking(Fourth FNPRM) should refer to WT Docket No. 02-55. Comments may be filed using: (1) The Commission's Electronic Comment Filing System (ECFS), (2) the Federal Government's eRulemaking Portal, or (3) by filing paper copies. See Electronic Filing of Documents in Rulemaking Proceedings, 63 FR 24121 (1998).

•Electronic Filers:Comments may be filed electronically using the Internet by accessing the ECFS:http://www.fcc.gov/cgb/ecfsor the Federal eRulemaking Portal:http://www.regulations.gov.Filers should follow the instructions provided on the Web site for submitting comments.

•Paper Filers:Parties who choose to file by paper must file an original and one copy of each filing. If more than one docket or rulemaking number appears in the caption of this proceeding, filers must submit two additional copies for each additional docket or rulemaking number.

5. Filings can be sent by hand or messenger delivery, by commercial overnight courier, or by first-class or overnight U.S. Postal Service mail. All filings must be addressed to the Commission's Secretary, Office of the Secretary, Federal Communications Commission.

• All hand-delivered or messenger-delivered paper filings for the Commission's Secretary must be delivered to FCC Headquarters at 445 12th St. SW., Room TW-A325, Washington, DC 20554. The filing hours are 8:00 a.m. to 7:00 p.m. All hand deliveries must be held together with rubber bands or fasteners. Any envelopes and boxes must be disposed of before entering the building.

• Commercial overnight mail (other than U.S. Postal Service Express Mail and Priority Mail) must be sent to 9300 East Hampton Drive, Capitol Heights, MD 20743.

• U.S. Postal Service first-class, Express, and Priority mail must be addressed to 445 12th Street SW., Washington, DC 20554.

6. Interested parties may view documents filed in this proceeding on the Commission's Electronic Comment Filing System (ECFS) using the following steps: (1) Access ECFS athttp://www.fcc.gov/cgb/ecfs.(2) In the introductory screen, click on “Search for Filed Comments.” (3) In the “Proceeding” box, enter the numerals in the docket number. (4) Click on the box marked “Retrieve Document List.” A link to each document is provided in the document list. The public may inspect and copy filings and comments during regular business hours at the FCC Reference Information Center, 445 12th Street SW., Room CY-A257, Washington, DC 20554. The public may also purchase filings and comments from the Commission's duplicating contractor, Best Copy and Printing, Inc., Portals II, 445 12th Street SW., Room CY-B402, Washington, DC 20554, telephone 1-800-378-3160, or via email tofcc@bcpiweb.com.The public may also download this Fourth Further Notice of Proposed Rulemaking from the Commission's web site athttp://www.fcc.gov/.

7.People with Disabilities:To request materials in accessible formats for people with disabilities (braille, large print, electronic files, audio format), send an email tofcc504@fcc.govor call the Consumer & Governmental Affairs Bureau at 202-418-0530 (voice), 202-418-0432 (tty).

8. Commenters who file information that they believe should be withheld from public inspection may request confidential treatment pursuant to Section 0.459 of the Commission's rules. Commenters should file both their original comments for which they request confidentiality and redacted comments, along with their request for confidential treatment. Commenters should not file proprietary information electronically.SeeExamination of Current Policy Concerning the Treatment of Confidential Information Submitted to the Commission,Report and Order,13 FCC Rcd 24816 (1998),Order on Reconsideration,14 FCC Rcd 20128 (1999). Even if the Commission grants confidential treatment, information that does not fall within a specific exemption pursuant to the Freedom of Information Act (FOIA) must be publicly disclosed pursuant toan appropriate request.See47 CFR 0.461; 5 U.S.C. 552. We note that the Commission may grant requests for confidential treatment either conditionally or unconditionally. As such, we note that the Commission has the discretion to release information on public interest grounds that does fall within the scope of a FOIA exemption.

9. This proceeding shall be treated as a “permit-but-disclose” proceeding in accordance with the Commission's ex parte rules. Persons making ex parte presentations must file a copy of any written presentation or a memorandum summarizing any oral presentation within two business days after the presentation (unless a different deadline applicable to the Sunshine period applies). Persons making oral ex parte presentations are reminded that memoranda summarizing the presentation must (1) list all persons attending or otherwise participating in the meeting at which the ex parte presentation was made, and (2) summarize all data presented and arguments made during the presentation. If the presentation consisted in whole or in part of the presentation of data or arguments already reflected in the presenter's written comments, memoranda or other filings in the proceeding, the presenter may provide citations to such data or arguments in his or her prior comments, memoranda, or other filings (specifying the relevant page and/or paragraph numbers where such data or arguments can be found) in lieu of summarizing them in the memorandum. Documents shown or given to Commission staff during ex parte meetings are deemed to be written ex parte presentations and must be filed consistent with 47 CFR 1.1206(b). In proceedings governed by 47 CFR 1.49(f) or for which the Commission has made available a method of electronic filing, written ex parte presentations and memoranda summarizing oral ex parte presentations, and all attachments thereto, must be filed through the electronic comment filing system available for that proceeding, and must be filed in their native format (e.g., .doc, .xml, .ppt, searchable .pdf). Participants in this proceeding should familiarize themselves with the Commission's ex parte rules.

10. Pursuant to the Regulatory Flexibility Act (RFA), the Federal Communications Commission's Public Safety and Homeland Security Bureau (Bureau) has prepared an Initial Regulatory Flexibility Analysis (IRFA) of the possible significant economic impact on small entities by the proposals considered in thisFourth FNPRM.The text of the IRFA is set forth in Appendix A. Written public comments are requested on this IRFA. Comments must be filed in accordance with the same filing deadlines for comments on the Fourth FNPRM, and they should have a separate and distinct heading designating them as responses to the IRFA. The Bureau will send a copy of the Fourth FNPRM, including the IRFA, to the Chief Counsel for Advocacy of the Small Business Administration.

11. This document proposes no additional information collection(s) subject to the Paperwork Reduction Act of 1995 (PRA), Public Law 104-13 beyond those already approved for this proceeding.SeeOMB Control No. 3060-1080 for Improving Public Safety Communications in the 800 MHz Band (exp. September 30, 2014). Therefore, it contains no new or modified “information collection burden for small business concerns with fewer than 25 employees,” pursuant to the Small Business Paperwork Relief Act of 2002, Public Law 107-198,see44 U.S.C. 3506(c)(4).

12. As required by the Regulatory Flexibility Act of 1980, as amended (RFA), the Federal Communications Commission's Public Safety and Homeland Security Bureau (Bureau) has prepared this Initial Regulatory Flexibility Analysis (IRFA) of the possible significant economic impact on small entities by the policies and rules proposed in thisFourth Further Notice of Proposed Rule Making(Fourth FNPRM). Written public comments are requested on this IRFA. Comments must be identified as responses to the IRFA and must be filed by the deadlines for comments on the first page of theFourth FNPRM.The Commission will send a copy of this Fourth FNPRM, including this IRFA, to the Chief Counsel for Advocacy of the Small Business Administration (SBA). In addition, theFourth FNPRMand IRFA (or summaries thereof) will be published in theFederal Register.

13. In theFourth FNPRM,the Bureau proposes channels plans for reconfiguring the 800 MHz band along the U.S.-Mexico border. The channel plans we propose in theFourth FNPRMwill be incorporated into the Commission's rules and are needed to implement and complete the Commission's band reconfiguration program along the U.S.-Mexico border. The Commission ordered reconfiguration of the 800 MHz band to address an ongoing nationwide problem of interference created by a fundamentally incompatible mix of technologies in the band. The Commission resolves the interference by reconfiguring the band to spectrally separate incompatible technologies. The Commission delegated authority to the Bureau in May 2007 to propose and adopt channel plans for implementing band reconfiguration along the U.S.-Mexico border. The band plans we propose in theFourth FNPRMwill separate incompatible technologies along the U.S.-Mexico border and thus resolve the ongoing interference problem in that region.

14. The proposed action is authorized under Sections 4(i), 301, 302, 303(e), 303(f), 303(r), 304 and 307 of the Communications Act of 1934, as amended, 47 U.S.C. Sections 154(i), 301, 302, 303(e), 303(f), 303(r), 304 and 307.

15. The RFA directs agencies to provide a description of and, where feasible, an estimate of the number of small entities that may be affected by the proposed rules, if adopted. The RFA generally defines the term “small entity” as having the same meaning as the terms “small business,” “small organization,” and “small governmental jurisdiction.” In addition, the term “small business” has the same meaning as the term “small business concern” under the Small Business Act. A small business concern is one which: (1) Is independently owned and operated; (2) is not dominant in its field of operation; and (3) satisfies any additional criteria established by the SBA. Pursuant to 5 U.S.C. 601(3), the statutory definition of a small business applies “unless an agency, after consultation with the Office of Advocacy of the Small Business Administration and after opportunity for public comment, establishes one or more definitions of such term which are appropriate to the activities of the agency and publishes such definition(s) in theFederal Register.” Below, we further describe and estimate the number of small entities that may be affected by the ruleschanges proposed in this Fourth FNPRM.

16.Private Land Mobile Radio Licensees (PLMR).PLMR systems serve an essential role in a range of industrial, business, land transportation, and public safety activities. These radios are used by entities of all sizes operating in all U.S. business and public sector categories, and are often used in support of the licensee's primary (non-telecommunications) operations. For the purpose of determining whether a licensee of a PLMR system is a small entity as defined by the SBA, we use the broad census category, Wireless Telecommunications Carriers (except Satellite). This definition provides that a small entity is any such entity employing no more than 1,500 persons. The Commission does not require PLMR licensees to disclose information about number of employees, so the Commission does not have information that could be used to determine how many PLMR licensees constitute small entities under this definition. We note that PLMR licensees generally use the licensed facilities in support of other business and governmental activities, and therefore, it would also be helpful to assess PLMR licensees under the standards applied to the particular industry subsector to which the licensee belongs.

17. As of May 2012, there were approximately 220 PLMR licensees operating in the PLMR band between 806-824/851-869 MHz along the U.S.—Mexico border. We note that many government and commercial actors are eligible to hold a PLMR license, and that any revised rules in this context could therefore potentially impact small entities covering a great variety of industries.

18. TheFourth FNPRMdoes not propose a rule that will entail additional reporting, recordkeeping, and/or third-party consultation or other compliance efforts beyond those already approved for this proceeding.SeeOMB Control No. 3060-1080 for Improving Public Safety Communications in the 800 MHz Band (exp. September 30, 2014).

19. The RFA requires an agency to describe any significant alternatives that it has considered in reaching its proposed approach, which may include the following four alternatives (among others): (1) The establishment of differing compliance or reporting requirements or timetables that take into account the resources available to small entities; (2) the clarification, consolidation, or simplification of compliance or reporting requirements under the rule for small entities; (3) the use of performance, rather than design, standards; and (4) an exemption from coverage of the rule, or any part thereof, for small entities.

20. TheFourth FNPRMwill create no significant economic impact on small entities because Sprint Nextel Corporation will pay all reasonable costs associated with retuning incumbent licensees to the post-reconfiguration channel plans proposed by the Bureau. Further, once the channel plans proposed in theFourth FNPRMare implemented, licensees will no longer be subject to on-going interference in the band and will therefore save costs that would otherwise be associated with resolving interference. Finally, the Bureau specifically seeks comment on alternatives to the proposed channel plans it proposes and will consider such alternatives as may be recommended in comments to theFourth FNPRM.

21. None.

22. Accordingly,it is ordered,pursuant to sections 4(i) and 332 of the Communications Act of 1934, as amended, 47 U.S.C. 154(i), 332, that thisFourth Further Notice of Proposed Rulemaking is adopted.

23.It is further orderedthat the Commission's Consumer and Governmental Affairs Bureau, Reference Information Center,shall senda copy of thisFourth Further Notice of Proposed Rulemaking,including the Initial Regulatory Flexibility Analysis, to the Chief Counsel for Advocacy of the Small Business Administration.

The pyrotechnic industry is a global logistics supply chain comprised of mostly foreign fireworks manufacturers and domestic importers, retailers, distributors, and consumers. Prior to the transportation into and throughout the U.S., all explosives, including Division 1.4 consumer fireworks, must be classed, approved, and issued a DOT EX classification approval number (EX number) by PHMSA. The EX number is a unique identifier that indicates a firework device has been classed and approved for transportation into and throughout the U.S.

PHMSA is committed to maintaining the exemplary transportation safety record that Division 1.4G consumer fireworks have displayed over the past forty years, but seeks to reduce burden and increase flexibility for the regulated community by providing an alternative to PHMSA's approval process. PHMSA has conducted an intensive retrospective review of the fireworks approval program and has determined that there is a delay in the processing of EX approval applications under the current regulatory scheme. PHMSA proposes an alternative option for Division 1.4G consumer fireworks in which applicants will submit applications for certification to a Fireworks Certification Agency (FCA), in lieu of submitting applications for approval to PHMSA. To ensure oversight of the proposed FCAs, this proposal includes reporting and recordkeeping requirements.

Additionally, PHMSA is proposing to define consumer fireworks and clarify the approval process for designation as a certification agency.

This NPRM affects the following entities and proposes the following requirements:

To monetize the costs and benefits of the proposals in this NPRM, PHMSA used a number of assumptions to develop a base case. The overall costs and benefits of the proposals are dependent on the assumption that all affected entities are currently complying with the regulations and that 50 to 90 percent of applicants will choose a DOT-approved FCA to certify that Division 1.4G consumer fireworks complies with the American Pyrotechnics Association's (APA) Standard 87-1 (IBR, see § 171.7), in lieu of filing an approval application with PHMSA.1 We believe this alternative process will be attractive to the fireworks industry as it will expedite the transportation process without compromising the current level of safety, enable shipments of Division 1.4G consumer fireworks to reach the market in a more timely manner, and consequently provide a cost savings. Cost in this scenario, includes the cost attributed to shipments that are delayed while approval applications are pending with PHMSA.

Costs associated with the proposals are primarily comprised of fees that FCAs may assess on manufacturers of Division 1.4G fireworks. There may also be costs associated with proposed recordkeeping requirements.2 Benefits will be derived from the expedited processing of consumer fireworks applications, resulting in faster time to market for each firework device. PHMSA estimates that the economic effects of this rulemaking, once finalized and adopted, will be sustained indefinitely. However, because of the difficulty of and uncertainty associated with forecasting industry effects into the far future, we assume a 10-year timeframe to outline, quantify, and monetize the costs and benefits of theproposals and to demonstrate the net effects of the proposals.

If the proposals in this NPRM are adopted, PHMSA estimates total annual benefits will be between approximately $14.5 million and $26.5 million, and total annual costs will be between $4 million and $7 million, resulting in total annual net benefits of between $11 million and $19 million. The table below summarizes the calculated cost and benefits associated with the NPRM.

PHMSA estimates the 10-year present value of the net benefits is about $80 million to $143 million (discounted at a 3 percent rate) or $55 million to $98 million (discounted at a 7 percent rate). PHMSA concludes that the aggregate benefits justify the aggregate costs. A summary of the range of expected annual costs and benefits is provided in the table below.3

PHMSA requests specific comments on the analysis underlying these estimates, including the percentage of entities that will choose to have their 1.4G consumer fireworks certified by FCAs instead of being approved by PHMSA, the manner in which records will be kept (i.e., electronic or paper), the estimated cost of the recordkeeping requirements, the number of affected entities (e.g., manufacturers and importers), and the estimated fee an FCA would charge for certification. We are also asking for general comments or suggestions regarding approaches to reduce the costs of this rule while maintaining or increasing the benefits. Additionally, PHMSA seeks comments on possible changes that might improve the rule and increase regulatory flexibility.

The requirements for the classification and packaging of Class 1 explosive materials are specified in Subpart C of Part 173 of the Hazardous Materials Regulations (HMR; 49 CFR parts 171—180). Fireworks are considered a Class 1 explosive material and must be classified under one of five hazard divisions and compatibility groups (1.1G, 1.2G, 1.3G, 1.4G, and 1.4S). As currently specified in Subpart C of Part 173 of the HMR, prior to transportation into and within the U.S., all explosives, including fireworks, must be approved and assigned a classification by PHMSA based on actual testing. Division 1.3 and 1.4 fireworks may also be approved in accordance with the American Pyrotechnics Association (APA) Standard 87-1.

Division 1.1 fireworks must be examined by a DOT-approved explosives test laboratory and assigned a recommended shipping description, division, and compatibility group in accordance with §§ 173.56(b), 173.56(f) or 173.56(i). Division 1.3 and 1.4 fireworks may either be approved in accordance with §§ 173.56(b), 173.56(f) or 173.56(i), or in accordance with § 173.56(j), which provides an option for obtaining an EX number and approval without prior testing by a DOT-approved explosives test laboratory.

Section 173.56(j) requires that the firework device is manufactured in accordance with APA Standard 87-1 and passes a thermal stability test. An applicant requesting PHMSA approval based on § 173.56(j) submits an application that contains required information specified in APA Standard 87-1. For example, the standard requires that the size of the device, as well as the various formulas and weights of each type of chemical composition contained in the device must be specified in the application. Only formulas containing chemicals identified in APA Standard 87-1, Table of “Standard Fireworks Chemicals” can be approved under the provisions of APA Standard 87-1. PHMSA has expanded on the Table of “Standard Fireworks Chemicals” to further detail chemicals that are permitted and prohibited in consumer fireworks devices.4 The manufacturer must submit a signed application with a detailed diagram of the device and certify thatthe device complies with APA Standard 87-1.

While both §§ 173.56(b) and 173.56(j) require the applicant to submit an application to PHMSA's Approvals and Permits Division for approval, the HMR provides a couple of alternatives. Under § 173.56(i), if experience or other data demonstrates that the hazard of a firework device containing an explosive chemical composition is greater or less than indicated according to the definition and criteria specified in §§ 173.50, 173.56, and 173.58, the Associate Administrator may specify a classification (including determining that it is forbidden from transportation), or except the device from the HMR. The HMR also permits the transport of firework devices the Associate Administrator approves on the basis of an approval issued by the competent authority of a foreign government, or when examination of the explosive by a person approved by the Associate Administrator is impracticable, on the basis of reports of tests conducted by disinterested third parties, as specified in § 173.56(f).

On May 10, 2012, President Obama issued Executive Order 13610 (Identifying and Reducing Regulatory Burdens) reaffirming the goals of Executive Order 13563 (Improving Regulation and Regulatory Review) issued January 18, 2011, and Executive Order 12866 (Regulatory Planning and Review) issued September 30, 1993. Executive Order 13610 directs agencies to prioritize “those initiatives that will produce significant quantifiable monetary savings or significant quantifiable reductions in paperwork burdens while protecting public health, welfare, safety, and our environment.” Executive Order 13610 further instructs agencies to give consideration to the cumulative effects of their regulations, including cumulative burdens, and prioritize reforms that will significantly reduce burdens.

Executive Order 13563, which supplements Executive Order 12866, directs federal agencies to periodically review existing significant regulations, retrospectively analyze rules that may be outmoded, ineffective, insufficient, or excessively burdensome, and modify, streamline, expand, or repeal regulatory requirements that are no longer justified. Agencies are also directed to consider regulatory approaches that reduce burdens and maintain flexibility and freedom of choice for the public.

In light of these Executive Orders and the President's continued efforts to streamline government regulations, we have evaluated our fireworks approval program to identify areas where we can improve efficiency, reduce burdens, and increase regulatory flexibility without diminishing safety. Specifically, we analyzed the timeline for reviewing applications for approval of fireworks devices. We found that over the past two years, PHMSA has reviewed roughly 30,000 applications for approval of fireworks devices. Approximately seventy-five percent of these applications sought approval for Division 1.4G consumer fireworks devices.

Due to the high volume of applications submitted for Division 1.4G consumer fireworks devices, the approximate review time per application is 120 days. Review time may be extended if applications are rejected for minor flaws, such as mathematical errors, or denied for safety issues. If an application is rejected, the applicant often resubmits the application placing it at the end of the review queue. If an application is denied, the applicant may file for reconsideration and subsequently may appeal to the Administrator; thereby delaying the final disposition of the application.

Consequently, the delay in processing applications can have an economic impact on the fireworks industry. For example, the lengthy approval process interrupts the supply chain and delays devices from reaching retail stores, which results in substantial revenue losses for U.S. importers, distributors and retail stores, many of whom are small businesses. Also, manufacturers of fireworks devices often charge U.S. purchasers storage fees for devices purchased that are pending approval and cannot be transported into and throughout the U.S.

After significant review of our fireworks program, we have identified areas that should be modified to decrease the delay in processing approvals. PHMSA is proposing to revise the HMR to provide an alternative option that will expedite the process for obtaining authorization to transport Division 1.4G consumer fireworks into and throughout the U.S., without compromising the current level of safety. PHMSA believes the revisions proposed in this NPRM will reduce burdens and enhance flexibility for the regulated community, while maintaining an equivalent level of safety provided in the HMR.5

In an effort to reduce regulatory burden and provide regulatory flexibility, without diminishing safety, PHMSA proposes structural changes to the regulations relating to PHMSA's fireworks program. Under the proposed revision, PHMSA will continue to approve Division 1.4G consumer fireworks in accordance with the current requirements specified in §§ 173.56(b), 173.56(f), 173.56(i), or 173.56(j). In addition to the current approval process, PHMSA proposes a new alternative that will permit manufacturers to apply to a DOT-approved Fireworks Certification Agency (FCA) to review and certify that Division 1.4G consumer fireworks comply with APA Standard 87-1 and are safe for transportation in commerce. To provide oversight of the DOT-approved FCAs, PHMSA is proposing reporting and recordkeeping requirements. PHMSA is also proposing to revise subpart E of part 107 to clarify the approval process for designation as a certification agency and provide for reconsideration of decisions to modify, terminate, or suspend a designation.

The proposed alternative process for Division 1.4G consumer fireworks will parallel the current requirements under § 173.56(j), except that, rather than submitting an approval application to PHMSA, the manufacturer or their U.S. designated agent will submit a certification application to a DOT-approved FCA to review and certify that the firework devices match the chemical compositions, sizes, and weights detailed in the application and that they meet the defining criteria set forth in APA Standard 87-1 to be classified as a Division 1.4G consumer firework.

In addition, PHMSA proposes to require the DOT-approved FCA conduct a physical examination of a sample of the Division 1.4G consumer firework design. This proposal is consistent with the requirements for other DOT-approved certification agencies. A DOT-approved FCA will be analogous to lighter certification agencies, which certify lighter designs, and independentinspection agencies, which evaluate and certify cylinder manufacturers. These entities physically examine the product (i.e., lighters or cylinders) to determine whether the product meets certain criteria specified in the HMR to ensure safe transportation of the product. Likewise, PHMSA proposes to require the DOT-approved FCAs physically examine a sample of the Division 1.4G consumer firework design type prior to initial shipment to determine whether the device meets the requirements of APA Standard 87-1 and matches the dimensions, chemical composition, and device type specified in the application for certification.

To become a DOT-approved FCA, the applicant will be required to submit an application with all procedures it will use to review and certify Division 1.4G consumer fireworks, in accordance with the provisions in subpart E of part 107. These procedures will be designed by the applicant; however, PHMSA will review the applicant's procedures to determine whether they are adequate to certify compliance with APA-Standard 87-1 and whether they provide an equivalent or greater level of safety to the current approval process. PHMSA plans to develop a guidance document for FCAs addressing standard procedures for the certification of Division 1.4G consumer fireworks.

Any domestic or foreign entity may apply to become a DOT-approved FCA provided that it is not directly or indirectly controlled by, or have a financial involvement with, any entity that manufactures, transports, or imports fireworks, except for providing services as an FCA. To qualify as a DOT-approved FCA, each applicant must: (1) Meet specific criteria designed to ensure that the FCA is an impartial, independent, unbiased, and qualified entity; (2) submit an application, including certification procedures; and (3) successfully complete a facility inspection performed by PHMSA. To meet the specific qualification criteria, the applicant will be required to demonstrate knowledge of the applicable regulations, including subpart C of part 173 of the HMR and the APA standard 87-1, the ability to review and evaluate design drawings and applications in accordance with the APA standard 87-1, and the ability to review and evaluate the qualifications of materials and fabrication procedures. If approved, PHMSA will issue an approval and an identifying number unique to that FCA. This number will provide traceability and enable PHMSA to seek corrective action or suspend or terminate certification authority if the requirements of the HMR or the FCA approval are not met.

Currently, all Division 1.4G fireworks devices are approved by PHMSA and assigned an EX number that represents that the fireworks article or device is in compliance with the classification requirements of the HMR. A current EX number approval begins with the letters “EX” followed by the year of issuance (e.g. 2012), the month of issuance, (e.g. 07), and the approval number issued that month, where “0001” indicates the first approval of the month. An example of the entire string of numbers appears as follows: “EX2012070001.”

To differentiate between an approval issued by PHMSA and a DOT-approved FCA certification, PHMSA proposes to use an FX numbering scheme. Instead of issuing an EX number and approval through PHMSA for a fireworks device, which is an inherently governmental function that cannot be reassigned, the DOT-approved FCA will issue a unique identifier (FX number) for devices it certifies as Division 1.4G consumer fireworks. The FX number will identify the DOT-approved FCA, the device, and the manufacturer. An example of an FX number would be “FX123-456.” In this example “123” will correspond to the DOT-approved FCA conducting the review and certification. This portion of the numbering sequence will be issued to the FCA by PHMSA. The “456” will represent a unique certification identifier traceable to both the manufacturer of the Division 1.4G consumer firework device and the device itself. This portion of the numbering sequence will be issued by the DOT-approved FCA. Each Division 1.4G consumer firework certified in this manner will be required to be marked and labeled in accordance with subpart D and E of part 172. As with EX numbers, marking the package with the FX number will not be required provided the FX number for each fireworks device is indicated on an accompanying shipping paper. The introduction of the FX numbering scheme will result in some Division 1.4G consumer fireworks being assigned an EX number when approved by PHMSA, and others being assigned an FX number when certified by a DOT-approved FCA.

Given the long history and wide recognition of the EX numbering scheme, PHMSA seeks specific comments on the supply chain implications, the economic impact and safety concerns associated with the proposed FX numbering system, as well as comments on how to implement the changes if they are adopted. For example, will the use of different alpha designators (i.e., EX and FX) pose complications or confusion within the transportation system?

PHMSA also seeks comments regarding alternative methods that may be used to identify Division 1.4G consumer fireworks devices that have been certified by a DOT-approved FCA, including suggestions in the alpha-numeric sequence that will facilitate transport while providing a clear distinction between PHMSA approved devices and devices certified by an FCA as compliant with APA standard 87-1.

PHMSA is proposing specific reporting and recordkeeping requirements to ensure that the DOT-approved FCAs are correctly certifying Division 1.4G consumer fireworks and are in compliance with the HMR and the FCA approval. As a condition of the FCA approval, each DOT-approved FCA will be required to submit to PHMSA electronic reports of the results of all devices submitted for certification on a schedule specified in the approval.

Additionally, for each firework device certified and issued an FX number, the DOT-approved FCA that reviewed the application, the manufacturer, and the importer will be required to maintain the device's thermal stability test report and a copy of the application. Currently, most consumer fireworks manufactured or assembled in the U.S. and those imported into the U.S. are voluntarily tested to ensure that they comply with the Consumer Product Safety Commission (CPSC) requirements. The testing facility, the manufacturers, and the importers utilizing this voluntary process are required to maintain records of these tests for three years.6 As it is current industry practice for importers to maintain similar records under the CPSC requirements, there will be limited additional paperwork burden for importers. The DOT-approved FCA will also be required to maintain a copy of the certification procedures used for each device certified. We propose thatFCAs, manufacturers and importers maintain these records for a period of five years; however, PHMSA will maintain the records for up to 10 years consistent with current practices for other approvals. The Associate Administrator, or designated official, may inspect the DOT-approved FCA's facilities and records to verify compliance with the recordkeeping requirements, the HMR, and the FCA approval.

PHMSA recognizes that under the proposed system manufacturers or their U.S. designated agents may attempt to submit duplicate applications to both a DOT-approved FCA and to PHMSA concurrently. As this new process is designed to promote efficiency while maintaining safety, the submission of duplicate applications under both processes may result in confusion, slower processing, and diminished safety. With this in mind, PHMSA proposes to require a signed certification statement on all applications submitted to either PHMSA or a DOT-approved FCA stating that an application was not submitted to any other entity. PHMSA will be able to verify that duplicative applications are not being submitted by reviewing the certification reports the DOT-approved FCAs will be required to submit to PHMSA. If a manufacturer or its U.S. designated agent submits identical applications to both a DOT-approved FCA and PHMSA, the manufacturer and its U.S. designated agent will be in violation of the HMR and the approval and may be fined under 18 United States Code, or imprisoned for not more than 5 years, or both, except the maximum amount of imprisonment may be 10 years in any case in which the violation involves the release of a hazardous material which results in death or bodily injury to any person (See § 107.333).

PHMSA anticipates that the proposed alternative certification process will reduce the processing time that it takes to evaluate an application. As a result, economic burdens caused by a delay in processing approvals will be reduced. Further, it may also promote innovation and potentially create new jobs, as currently no DOT-approved FCAs exist. Additionally, PHMSA will continue to require that Division 1.4G consumer fireworks comply with all other requirements in the HMR, including the shipping paper, marking, labeling, placarding, and incident reporting requirements to ensure safety is not diminished.

Should the proposed alternative option be adopted in a future rulemaking, PHMSA plans to develop a guidance document addressing standard operating procedures for the certification of Division 1.4G consumer fireworks. The publication of this guidance document will coincide with the final rule publication.

PHMSA seeks general comments on the proposed changes to the fireworks program. PHMSA seeks specific comments on the need for revision of the fireworks program, the economic impact of the proposed changes, safety concerns associated with the proposed changes, as well as comments on how to implement the changes if they are adopted. PHMSA also seeks comments on whether the proposed record retention period of five years is adequate or if the retention period should be expanded to address the longer shelf life of some consumer fireworks. In addition, PHMSA invites all stakeholders and affected entities, including the CPSC, the Bureau of Alcohol, Tobacco, Firearms and Explosives, Customs and Border Patrol, and state and/or local fire and police departments to comment on the proposals.

In an effort to reduce regulatory burden and provide industry more flexibility, we are proposing structural changes to the regulations relating to PHMSA's fireworks program. Specifically, PHMSA proposes to revise the requirements in five sections (§§ 107.402, 107.403, 172.320, 173.56 and 173.59), add two new sections (§§ 173.64 and 173.65), and reserve one section (§ 107.405). The specific revisions and additions to these sections are detailed below by topic.

We propose moving the current requirements of § 173.56(j) to a standalone new § 173.64 entitled “Exceptions for Division 1.3 and 1.4 Fireworks.” In addition, we propose the addition of a new § 173.65 entitled “Exceptions for Division 1.4G Consumer Fireworks” that will detail the alternative certification process for Division 1.4G consumer fireworks. To correspond to the changes proposed in this NPRM, we will revise the entry “UN0336 Fireworks” in § 172.101 Hazardous Materials Table. Further, a definition for “consumer firework” will be added to § 173.59. No modifications are proposed for §§ 173.56(f) and 173.56(i).

The hazard communication requirements for Division 1.4G consumer fireworks will be specified in paragraph (c) of the new § 173.65 and the revised § 172.320. Specifically, § 172.320 will be revised to reflect the addition of FX numbers.

The process for applying for an approval to operate as a DOT-approved FCA will be found in the proposed revised § 107.402 entitled “Application for designation as a certification agency.” General application requirements for designation as a certification agency will be moved to § 107.402(b). No new general application requirements are being proposed in this NPRM. Application requirements specific to Packing and Lighter Certification Agencies will be moved to § 107.402(c). No new application requirements specific to Packing and Lighter Certification Agencies are being proposed in this NPRM. Application requirements to become a DOT-approved FCA will be found in the proposed § 107.402(d).

To clarify and provide consistency in the procedural process for designation as a certification agency, the subpart E heading will be entitled “Designation of Certification Agencies.” The words “as an approval or” will be removed from § 107.402. The word “approval” will be replaced with “certification” in the § 107.403 heading.

Reconsideration for a denial of designation as a fireworks certification agency will be found in § 107.403(c), which will be revised to provide that the procedural requirements of subpart H of this part apply to the process for reconsideration of denials of designations. A new subparagraph (d) will be added to § 107.403 to provide that the procedural requirements of subpart H of this part will also apply to the process for modification, suspension, and termination of designations. Section 107.405 will be deleted and reserved.

An overview of the proposed process to be recognized by PHMSA as a DOT-approved FCA is detailed in Figure 1 below.

The procedures for a manufacturer of Division 1.4G consumer fireworks or its U.S. designated agent to submit an application for certification to a DOT-approved FCA will be specified in the new § 173.65(a). These requirements parallel those currently in § 173.56(j); however, they address certification by a DOT-approved FCA, as opposed to PHMSA approval, and describe that fireworks utilizing this review process will be issued an FX number, in lieu of an EX number. The current approval process will continue to be available; however, manufacturers and their U.S. designated agents may voluntarily use the FCA process as an alternative.

Diagrams of the current (Figure 2) and proposed (Figure 3) consumer fireworks application processes are shown below.

Section 4(b)(3)(B) of the Endangered Species Act of 1973, as amended (Act) (16 U.S.C. 1531et seq.), requires that, for any petition to revise the Federal Lists of Endangered and Threatened Wildlife and Plants that contains substantial scientific or commercial information that listing a species may be warranted, we make a finding within 12 months of the date of receipt of the petition. In this finding, we will determine that the petitioned action is: (1) Not warranted, (2) warranted, or (3) warranted, but the immediate proposal of a regulation implementing the petitioned action is precluded by other pending proposals to determine whether species are either an endangered or threatened species, and expeditious progress is being made to add or remove qualified species from the Federal Lists of Endangered and Threatened Wildlife and Plants. Section 4(b)(3)(C) of the Act requires that we treat a petition for which the requested action is found to be warranted but precluded as though resubmitted on the date of such finding, that is, requiring a subsequent finding to be made within 12 months. We must publish these 12-month findings in theFederal Register.

On July 30, 2007, we received a petition dated July 24, 2007, from Forest Guardians (now WildEarth Guardians), requesting that 206 species in the Mountain-Prairie Region, including the Platte River caddisfly, be listed as an endangered or threatened species under the Act, and critical habitat be designated. Included in the petition were analyses, references, and documentation provided by NatureServe in its online database athttp://www.natureserve.org/. We acknowledged receipt of the petition in a letter to the petitioners, dated August 24, 2007, and stated that, based on preliminary review, we found no compelling evidence to support an emergency listing for any of the species covered by the petition. In that letter we also stated that we would begin to assess the information provided in the petition in October 2007.

We published a partial 90-day finding for 38 of the petition's 206 species in theFederal Register(74 FR 41649) on August 18, 2009; the Platte River caddisfly was one of 29 species for which we found there was substantial information indicating that listing may be warranted under the Act. In that document, we announced that we were initiating a status review. On January 12, 2010, WildEarth Guardians filed a complaint indicating that the Service failed to comply with the statutory deadline to complete a 12-month finding for the Platte River caddisfly. This complaint was consolidated with several others, and a multi-district settlement agreement with WildEarth Guardians was approved on September 9, 2011, which included an agreement that the Service would complete the 12-month finding for the Platte River caddisfly by the end of Fiscal Year 2012. Funding for completing the 12-month finding became available in Fiscal Year 2011, and we began work at that time. This notice constitutes the 12-month finding on the July 24, 2007, petition to list the Platte River caddisfly as an endangered or threatened species.

The Platte River caddisfly (Ironoquia plattensis)adult is a small, brown, moth-like insect with a body length of 5.5-6.5 millimeters (mm) (0.21-0.26 inches (in)) and forewing length of 6.5-8.0 mm (0.26-0.31 in) (Alexander and Whiles 2000, p. 2). Wing membranes and veins are light or iridescent brown with white spotting (Alexander and Whiles 2000, p. 2). The Platte River caddisfly has a short proboscis (tubular mouthpart used for feeding) and long antennae, similar to other species of caddisflies (Holzenthalet al.2007, p. 648). Platte River caddisfly adults can be distinguished from those of other species in theIronoquiagenus by their much smaller size (forewing length of 6.5-8.0 mm (0.26-0.31 in) in Platte River caddisflies contrasting with >14 mm (0.55 in) in most otherIronoquiaspecies) (Alexander and Whiles 2000, p. 2).

Like several caddisfly species, Platte River caddisfly larvae construct a case around the abdomen (Mackay and Wiggins 1979, p. 186). All caddisflies produce silk from modified salivary glands, and case-making caddisfly larvae use this silk to fuse together organic or mineral material from the surrounding environment (Mackay and Wiggins 1979, pp. 185-186; Holzenthalet al.2007, p. 644). Cases are generally thought to protect larvae by providing camouflage against predation or resistance to crushing (Mackay and Wiggins 1979, p. 200; Otto and Svensson 1980, p. 855). The Platte River caddisfly case is composed of sand grains and can be up to 16.0 mm (0.63 in) long, while larvae can attain sizes up to 14.0 mm (0.55 in) in length (Vivian 2010, pers. obs.).

Platte River caddisfly larvae have a light brown head and thorax and a yellowish to whitish abdomen (Vivian 2010, pers. obs.), much like the larvae ofIronoquia parvula(no common name) (Flint 1958, p. 59). Larvae in theIronoquiagenus can be distinguished from larvae in other caddisfly genera by four morphological characteristics that are distinguishable under a microscope (Flint 1958, p. 59; Wiggins 1977, p. 248). Differences in larval size (Alexander and Whiles 2000, p. 1) and case material among species have also been noted (Wiggins 1977, p. 248).

The Platte River caddisfly was formally described as a new species in the order Trichoptera (caddisflies) in 2000 by Alexander and Whiles (2000, p. 2). The Platte River caddisfly is in the family Limnephilidae, or the northern caddisflies, subfamily Dicosmoceniae, and genusIronoquia(Wiggins 1977, p. 181; Alexander and Whiles 2000, p. 1).

The caddisfly family Limnephilidae is considered to be the most ecologically diverse family of Trichoptera (Holzenthalet al.2007, p. 674) and is the largest caddisfly family in North America, with over 900 species in more than 100 genera (Holzenthalet al.2007, p. 674). The Limnephilidae family is dominant at higher latitudes and elevations, has the widest distribution of any caddisfly family, and comprises one-third of all Nearctic (ecozone comprising Arctic and temperate areas of North America and Greenland) caddisfly species (Wiggins 1977, p. 179). Caddisflies in this family may be collected from springs, pools, seeps, marshes, bogs, fens, streams, rivers, and lakes (Wiggins 1977, p. 179). Limnephilids largely feed on larger bits of plant material, such as fallen leaves, or organic materials that form atop rock surfaces (Wiggins 1977, p. 179).

TheIronoquiagenus belongs to the subfamily Dicosmoceniae, which mostly occurs in cool, lotic (running water) environments, except forIronoquia,which occurs in temporary pools (Flint1958, p. 59; Wiggins 1977, p. 248). The genusIronoquiais comprised of six species: the Platte River caddisfly (I. plattensis),I. punctatissima(no common name) (Walker 1852),I. parvula(no common name) (Flint 1958),I. dubia(no common name) (Stephens 1837),I. lyrata(no common name) (Ross 1938), andI. kaskaskia(no common name) (Ross 1944), with the Platte River caddisfly being the most recently described (Encyclopedia of Life 2011, entire). All of these species exceptI. dubia(Europe) occur only in North America (Williams and Williams 1975, p. 829; Ćuk and Vučković 2010, pp. 232, 234).

Ironoquiais the only genus within the Dicosmoceniae subfamily that occurs in temporary waters (Wiggins 1977, p. 248). In North America,Ironoquiais mostly found throughout the central and eastern portions of the United States (Wiggins 1977, p. 248) and is most often collected from temporary pools or wetlands but can also occur in perennial waters (Flint 1958, p. 61; Ćuk and Vučković 2010, p. 234). The Platte River caddisfly has been found to co-occur withI. punctatissima,which is a common species on the Great Plains, butI. punctatissimais morphologically distinct and much larger than the Platte River caddisfly (Alexander and Whiles 2000, p. 1; Gelusoet al.2011, p. 1024).

The Platte River caddisfly is thought to be most closely related toI. parvula(Alexander and Whiles 2000, p. 1), which occurs in Ohio and the northeastern United States (Flint 1958, p. 59; Wiggins 1977, p. 248; Swegmanet al.1981, p. 141; Garono and MacLean 1988, p. 148). Platte River caddisfly adults are smaller and have lighter color and more pronounced spotting on the wings thanI. parvula(Alexander and Whiles 2000, p. 2). We find that Alexander and Whiles (2000, entire) provide the best available information on the taxonomy of the Platte River caddisfly, and no other challenges to the taxonomy have been raised since the Platte River caddisfly was described. Therefore, we consider the Platte River caddisfly a valid species for listing under the Act.

The Platte River caddisfly was discovered in 1997, in a warm-water slough (backwater area or marsh that is groundwater fed) in south-central Nebraska along the Platte River on Mormon Island (hereafter type locality), which is land owned by the Platte River Whooping Crane Maintenance Trust (hereafter Crane Trust (a conservation organization)) southwest of Grand Island, Nebraska (Whileset al.1999, p. 534; Goldowitz 2012, pers. comm.). This slough had an intermittent hydroperiod (duration of inundation) and held water 75-90 percent of the time or about 275-330 days out of the year (Whileset al.1999, p. 534; Goldowitz 2004, pp. 2-3). The area lacked trees (Whileset al.1999, p. 534) and was located within the largest remaining tract of native prairie in the Central Platte Valley (Goldowitz 2004, p. 2).

Intermittent wetlands, such as the type locality, have been described as any water body that holds water for about 8 to 10 months during the year (Wigginset al.1980, p. 100); some intermittent sites may or may not completely dry in a year (Tarr and Babbitt 2007, p. 6). These wetlands differ from ephemeral wetlands (that hold water for a relatively short period of time (e.g., 4 months)) and permanent wetlands (rarely dry) (Tarr and Babbit 2007, p. 6). Intermittent wetlands dry when the groundwater table drops below the ground surface.

Since the Platte River caddisfly was discovered, surveys have mostly found the caddisfly in sloughs with intermittent hydroperiods; however, the caddisfly has also been found in sloughs with permanent hydroperiods (Goldowitz 2004, p. 5; Meyer and Whiles 2008, p. 632; Vivian 2010, p. 54; Gelusoet al.2011, p. 1024). In sloughs with permanent hydroperiods, the caddisfly has been observed in lower numbers, which is true of otherIronoquiaspecies, likely because of the presence of more predators in permanent waters(Wigginset al.1980, p. 148; Vivian 2010, p. 54). The caddisfly has not been observed in ephemeral wetlands (Vivian 2009, pers. obs.).

In general, the intermittent wetlands where the caddisfly occurs are found along the floodplains of the Platte, Loup, and Elkhorn Rivers in central Nebraska (LaGrange 2004, p. 15) and are shallow, linear depressions that are historical channel remnants of these river systems (Friesenet al.2000, p. 4-8). The presence of water in these sloughs is influenced by groundwater levels and trapped surface run-in (Friesenet al.2000, p. 4-8). Groundwater levels are controlled by river stage (flows), precipitation, and evapotranspiration (Wescheet al.1994, p, iii). Platte River flows are principally tied to snowmelt from the Rocky Mountains and local precipitation events (Simons and Associates 2000, pp. 2-5), while Loup River and Elkhorn River flows are tied to the Ogallala Aquifer (Petersonet al.2008, p. 5). Sloughs that support the caddisfly vary in their distance to the main river channel. Most sloughs are adjacent to the main channel, while some occur in areas more than 0.4 kilometers (km) (0.25 miles (mi)) away.

Sloughs with the Platte River caddisfly are typically described as lentic (with little to no flow) (Whileset al.1999, p. 533; Alexander and Whiles 2000, p. 2). However, two sites do contain some flow, and the caddisfly appears to occur in higher densities in areas with flowing water than in stagnant areas (Harner 2012, pers. comm.). Because of their groundwater connection, sloughs with the caddisfly may maintain thick ice cover on surface waters through the winter without completely freezing to the bottom (Whileset al.1999, p. 534; Goldowitz 2004, p. 2). Slough substrata often consist of a thick layer of detritus and silt overlying sand (Whileset al.1999, p. 534; Alexander and Whiles 2000, p. 6). Soils in the sloughs consist of a mixture of loam, sand, and gravelly sand and tend to be frequently flooded and poorly drained (Natural Resources Conservation Service (NRCS) Web Soil Survey 2009, entire).

Because it is an inhabitant of intermittent waters, the Platte River caddisfly is tolerant of large fluctuations in water chemistry (Williams 1996, p. 634; Whileset al.1999, p. 534). Large variations in water quality (e.g., pH, conductivity, total dissolved solids, dissolved oxygen, turbidity, and temperature) have been observed among five forested sites where the caddisfly occurs (Vivian 2010, pp. 81, 96). Furthermore, average conductivity and pH in sloughs with the caddisfly reported by Vivian (2010, pp. 81, 96) differed from the average values reported by Whileset al.(1999, p. 534) and Gelusoet al.(2011, p. 1022). The gradient of water chemistry observed between forested sloughs and the type locality is likely a result of the differences in habitat types, and demonstrates that the Platte River caddisfly can withstand a broad range of water quality.

Vegetation in sloughs occupied by the caddisfly is typical wetland flora, such asTyphaspp. (cattails),Schoenoplectus fluviatilis(river bulrush),Eleocharisspp. andCyperusspp. (sedges), andLemnaspp. (duckweed); some sloughs support nonnative, invasive vegetation, includingPhalaris arundinacea(reed canarygrass),Phragmites(common reed), andLythrum salicaria(purple loosestrife). Plant species along slough banks and margins include woody species, such asFraxinus pennsylvanica(green ash) andPopulus deltoides(cottonwood), and grass species, such asSpartina pectinata(prairie cordgrass)and smooth brome (Bromus inermis,invasive). Various forbs are also present throughout the slough. Most areas where the Platte River caddisfly has been observed since it was described have an abundance of woody vegetation, which contrasts with the treeless, wet meadow environment encountered at the type locality and one other population at the Crane Trust (Whileset al.1999, p. 534; Vivian 2010, p. 56; Vivian 2011, pp. 33-35). Overall, the Platte River caddisfly is tolerant of a range of conditions, including variations in hydroperiod, water quality, and vegetation, but thrives in intermittent sloughs.

The Platte River caddisfly lifecycle was characterized by Whileset al.(1999, entire). The caddisfly is univoltine (one generation per year). The adult flight period for the Platte River caddisfly is between late September and mid-October. Adults first emerge around late-September and live for about 7 to 10 days, with the entire emergence period lasting 3 to 4 weeks. While active, adults oviposit (lay eggs) on the surface film of the water, the eggs sink to the bottom of the slough, and larvae hatch as first instars (life stage between molts) sometime in November. Aquatic larvae overwinter in the slough as first instars. In late winter, larvae construct their case (Vivian 2010, pers. obs.) and begin feeding and growing rapidly and proceed through four more instars. Between late April and early June, fifth (final) instars climb upslope from the water and aestivate (pass stressful time periods in a dormant condition) during the summer months when it is typically dry along the adjacent slough banks (Whileset al.1999, pp. 535-536; Gelusoet al.2011, p. 1023). Platte River caddisfly larvae eventually pupate (metamorphose between larva and adult) along slough margins in the larval case. Pupation lasts about 4 weeks until adult emergence in late September.

While in its aquatic stage, the Platte River caddisfly is considered a shredder and largely feeds upon senescent (aged) plant tissue (Whileset al.1999, pp. 542-543). As one of the few shredders present in sloughs, the Platte River caddisfly plays an important role in the decomposition of organic matter in these systems (Whileset al.1999, pp. 539, 543). In its terrestrial stage, the Platte River caddisfly does not feed (Whileset al.1999, p. 537), and as an adult, the species has the ability to ingest liquids (Holzenthalet al.2007, p. 648).

The Platte River caddisfly likely has a lifecycle adapted to the intermittent wetlands found along the Platte, Loup, and Elkhorn River systems (Whileset al.1999, p. 537; Vivian 2010, pers. obs.). For example, larval emigration to adjacent mesic grassland habitat and adult emergence were found to coincide with early summer drying and fall inundation of the wetlands, respectively (Whileset al.1999, pp. 537, 542). The Platte River caddisfly is dependent upon water for the egg and larval stages of its lifecycle, (e.g., for at least 7 to 8 months out of the year) (Whileset al.1999, pp. 537-539).

While most caddisflies have an entirely aquatic larval phase, allIronoquiaspecies are known to aestivate in leaf litter near the receding water line during the summer months prior to pupating (Flint 1958, p. 61; Williams and Williams 1975, p. 830; Wiggins 1977, p. 248; Johansson and Nilsson 1994, p. 21; Whileset al.1999, p. 534). However, some aestivating Platte River caddisfly larvae have been found to burrow beneath the ground surface (Gelusoet al.2011, p. 1024). This behavior may be a way to withstand summer drying of sloughs or to avoid desiccation, as reported for other caddisflies (Mackay and Wiggins 1979, p. 187; Wigginset al.1980, p. 179; Johannson and Nilsson 1994, p. 21; Gelusoet al.2011, p. 1024), as soil temperatures in unshaded areas can reach 54 degrees Celsius (°C) (129 degrees Fahrenheit (°F)) in the summer (Vivian 2010, pers. obs.). This behavior could protect aestivating larvae against late spring (May-June) flows, which are characteristic of the Platte River system and could scour (wash) larvae downstream (Simon and Associates 2000, p. 8) and other disturbances characteristic of the Great Plains ecosystem, such as livestock grazing (Gelusoet al.2011, p. 1024).

Data collection on the range of the Platte River caddisfly began in 1999, shortly after it was discovered, and continued in 2004 (Goldowitz 2004, p. 3). Surveys were conducted at 48 locations along the Platte and Loup Rivers, and the Platte River caddisfly was found at 9 of these sites (Goldowitz 2004, p. 5). These populations occupied an approximately 100-km (60-mi) stretch of the central Platte River that extends from south of Gibbon, Nebraska (Kearney County), to Central City, Nebraska (Merrick County). Surveys for the caddisfly on the Loup River were negative (Goldowitz 2004, p. 9). Monitoring efforts in 2004 did not find the caddisfly at the type locality, despite a consistent adult emergence pattern in the preceding 7 years and the species' prior abundance at that site (Goldowitz 2004, p. 8). Because of its apparent rarity, the caddisfly was designated a Tier 1 species in Nebraska as per the State's natural legacy plan (Schneideret al.2005, p. 93). Tier 1 species are those that are at risk of extinction on a global scale or at risk of becoming extirpated from Nebraska (Schneideret al.2005, p. 17).

Through 2004, the Platte River caddisfly was only known from the Platte River (Goldowitz 2004, p. 9). However, surveys for new Platte River caddisfly populations resulted in the discovery of the species on the Loup and Elkhorn Rivers in Nebraska in 2009 and 2010 (Vivian 2010, p. 50). Close visual examination of adults and larvae at sites on the Loup and Elkhorn Rivers demonstrated that the species was notI. parvulaand confirmed the presence of the Platte River caddisfly on these systems. However, because of the distance between some caddisfly populations on the Platte, Loup, and Elkhorn Rivers, we determined there was a need to identify potential genetic differences for the species among sites. Genetic analyses indicated that there is a low amount of gene flow among all three rivers, and that a population tested on the Elkhorn River was genetically divergent, but not different, from the populations on the Platte and Loup Rivers (Cavallaroet al.2011, p. 7). This genetic divergence appears to be a product of geographic isolation as opposed to habitat fragmentation.

The Platte River is formed at the confluence of the North Platte and South Platte Rivers in west-central Nebraska, just east of North Platte, and generally flows east until it meets the Missouri River along the eastern edge of Nebraska (Williams 1978, pp. 1-2). The North Platte River originates in the Rocky Mountains of Colorado, flows north through central Wyoming and then southeast into Nebraska (Williams 1978, p. 1); the South Platte River originates in Colorado and flows northeast until it meets the Platte River at North Platte, Nebraska (Simons and Associates 2000, p. 2). Platte River flows are largely dependent upon snowmelt from the Rocky Mountains and local precipitation events (Simons and Associates 2000, pp. 2-5).

The Loup and Elkhorn Rivers are tributaries of the Platte River system. The Loup River contains several tributaries, including the North Loup, Middle Loup, South Loup, and Cedar Rivers in Nebraska. The Loup River isformed at the confluence of the Middle Loup and North Loup Rivers near St. Paul, Nebraska, and flows east until it meets the Platte River at Columbus, Nebraska, in the eastern third of the State. The Loup River drains groundwater from the Sandhills and the underlying Ogallala Aquifer, and its tributaries flow northwest to southeast, while the Loup flows east or northeast until it meets the Platte River (Petersonet al.2008, pp. 2-5). The Elkhorn River drains wet meadows and plains in north-central Nebraska, and flows east-southeast until it meets the Platte River near Omaha, Nebraska (Petersonet al.2008, pp. 2-5).

In Nebraska, there is a gradient of precipitation from west to east. Just east of the Rocky Mountains in central Nebraska there is a predominant rain shadow effect that results in low amounts of precipitation in western Nebraska. Precipitation generally increases as one travels east towards Nebraska's eastern border (Simon and Associates 2000, p. 2).

Surveys for the Platte River caddisfly between 2009 and 2011 identified 35 caddisfly populations out of 115 sites visited, including 5 of the 9 sites identified by Goldowitz (2004, entire) (Vivian 2010, p. 46; Gelusoet al.2011, entire; Figure 1 below). With these recent survey efforts, the caddisfly is now known from a 390-km (240-mi) stretch of the Platte River that runs from near Sutherland, Nebraska (Lincoln County), to near Schuyler, Nebraska (Platte County), and from the Loup and Elkhorn River systems (Figure 1 below). Within this range, there is approximately a 155-km (93-mi) gap in the distribution of the caddisfly between Hershey, Nebraska, and Elm Creek, Nebraska (Vivian 2010, p. 51). Twenty-four surveys for the caddisfly were conducted in this gap, and the caddisfly was not found (Vivian 2010, p. 50).

From recent survey efforts, one site near Shelton, Nebraska, is presumed extirpated (Riens and Hoback 2008, p. 1; Vivian 2010, p. 48). Also, the Platte River caddisfly was observed at the type locality in 2010 (Gelusoet al.2011, p. 1023), after not having been observed there during surveys in 2004 and 2007-2009 (Goldowitz 2004, p. 8; Riens and Hoback 2008, p. 1; Vivian 2010, p. 53). Survey work in 2009-2011 also identified 13 sites along the Platte, Loup, Elkhorn, and Cedar Rivers that contained discarded larval cases but no live individuals (Vivian 2010, p. 46). Finding a site with a caddisfly case in a slough along the Cedar River indicates that the Platte River caddisfly is likely present in the basin. However, observing live individuals at a site is needed to confirm its presence there, because it is thought that discarded larval cases degrade slowly and could represent generations from previous years (Vivian 2010, pp. 49, 55-56).

Aside from the Cedar River, it appears that more surveys for the Platte River caddisfly could result in the discovery of additional populations on other river drainages in Nebraska, including the Niobrara and Republican Rivers. More survey work on the Platte, Loup, and Elkhorn drainages would likely result in the discovery of new populations on these systems as well. Between 2009and 2011, satellite imagery was used to identify potential caddisfly habitat throughout Nebraska prior to conducting surveys (Vivian 2010, p. 38). There are additional areas of remaining potential Platte River caddisfly habitat along Nebraska's major river systems that have yet to be surveyed (Vivian 2011, pers. obs.). Thus, ongoing surveys are likely to expand the known range of the Platte River caddisfly.

At the type locality, the Platte River caddisfly was considered an abundant component of the slough ecosystem. In 1997-1998, an average of 805 ± 194 larvae per square meter (m2) was observed throughout the aquatic life stage of the caddisfly lifecycle, and 410.67 larvae per m2were present in the aquatic environment in May 1998 (Whileset al.1999, pp. 537, 540). Gelusoet al.(2011, p. 1022) reported a mean density of 553 ± 284 Platte River caddisfly larvae per m2(n = 19) from a site at the Crane Trust on Shoemaker Island (hereafter “Wild Rose Slough”), which is located about 5 km (3.2 mi) upstream of the type locality. With the exception of these two sites, the Platte River caddisfly has been found to occur in lower densities (Whileset al.1999, pp. 539-540).

In May of 2009 and 2010, aquatic larval densities were measured at 18 sites with a Platte River caddisfly population on the Platte River only, and larval densities ranged from zero to 125.7 individuals per m2(Vivian 2010, p. 64). Aestivating (terrestrial life stage) larval densities at 12 of 13 sites sampled ranged from zero to 116 individuals per m2(Vivian 2010, p. 65). Day and nighttime sampling found anywhere between zero and eight adults per hour of observation (Vivian 2010, pp. 65-66).

The aquatic and terrestrial larval densities reported by Vivian (2010, pp. 40-41) are not directly comparable to Whileset al.(1999, p. 535), because different methodologies were used, and a different volume of sediment was sampled during the aquatic sampling period (Meyeret al.2011, p. 110). Meanwhile, Gelusoet al.(2011, p. 1022) used the same aquatic sampling method as Vivian (2010, pp. 40-41) but sampled slightly earlier in 2010. Nonetheless, the methods used during 2009-2010 sampling were internally consistent, and these results demonstrate that the caddisfly occurs in varying densities across its range (Vivian 2010, pp. 40-41; Harner 2012, pers. comm.). Although some densities reported by Vivian (2010) are low compared to what has been reported for other caddisfly species (Mayer and Likens 1987, p. 266; Roeding and Smock 1989, p. 152; Bunn and Hughes 1997, pp. 343-344; Stewart and Downing 2008, p. 145), observations on the numbers and density variations of Platte River caddisfly larvae and adults are consistent with those reported for otherIronoquiaspecies (Flint 1958, p. 60; Swegmanet al.1981, p. 131; MacLean and MacLean 1984, p. 56; Garono and MacLean 1988, p. 147; Gray and Johnson 1988, p. 180; Ćuk and Vučković 2010, pp. 233-234). Therefore, the Platte River caddisfly andIronoquiaspp., in general, are more abundant in some areas than in others.

Although population densities have been reported for over half of all known Platte River caddisfly populations, there is a lack of general information on population trends for this species, with the exception of a few sites, including the type locality, Wild Rose Slough, one site near Shelton, Nebraska, and one site near Chapman, Nebraska, where restoration work conducted by the Service in 2007 resulted in a population decline at that site. Sites with lower population densities may always remain naturally low. Therefore, with the information available and the increase in the number of known populations, it is difficult to discern if the number of Platte River caddisfly individuals and populations is remaining steady, increasing, or decreasing.

Section 4 of the Act (16 U.S.C. section 1533) and implementing regulations (50 CFR part 424) set forth procedures for adding species to, removing species from, or reclassifying species on the Federal Lists of Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of the Act, a species may be determined to be an endangered or threatened species based on any of the following five factors:

(A) The present or threatened destruction, modification, or curtailment of its habitat or range;

(B) Overutilization for commercial, recreational, scientific, or educational purposes;

(C) Disease or predation;

(D) The inadequacy of existing regulatory mechanisms; or

(E) Other natural or manmade factors affecting its continued existence.

In making this finding, information pertaining to the Platte River caddisfly in relation to the five factors provided in section 4(a)(1) of the Act is discussed below. In considering what factors might constitute threats to a species, we must look beyond the exposure of the species to a particular factor to evaluate whether the species may respond to that factor in a way that causes actual impacts to the species. If there is exposure to a factor and the species responds negatively, the factor may be a threat and, during the status review, we attempt to determine how significant a threat it is. The threat is significant if it drives, or contributes to, the risk of extinction of the species such that the species warrants listing as endangered or threatened as those terms are defined in the Act. However, the identification of factors that could impact a species negatively may not be sufficient to compel a finding that the species warrants listing. The information must include evidence sufficient to suggest that these factors are operative threats that act on the species to the point that the species may meet the definition of an endangered or threatened species under the Act.

Reductions in groundwater levels or river flows as a result of water development can adversely impact aquatic habitats and their associated macroinvertebrate communities. Existing and future water development along the Platte, Loup, and Elkhorn Rivers could adversely impact the Platte River caddisfly and its habitat. Adverse impacts could occur through the loss of water during critical life stages or changes in hydrology that result in intermittent wetlands becoming too ephemeral to support the Platte River caddisfly. We examine this topic in detail below.

Hydroperiod can be an important factor in determining the composition of macroinvertebrate communities in wetlands. For instance, Whiles and Goldowitz (2005, p. 466) found that slough hydroperiod influenced macroinvertebrate taxa diversity and abundance, with more taxa present in intermittent sloughs than in sloughs with more ephemeral or permanent hydroperiods. Sloughs with intermittent hydroperiods typically have fewer predators than permanent wetlands and can offer safe refugia for various taxa if they can withstand habitat drying (Williams 1996, p. 634; Wissingeret al.1999, p. 2103; Tarr and Babbitt 2007, p. 3). Sites with more permanent hydroperiods likely offer a more suitable environment for potential predators of the caddisfly, such as fish and amphibians, thereby reducing larval densities (Whiles and Goldowitz 2001,p. 1836; Whiles and Goldowitz 2005, pp. 468, 470). Certain permanent sloughs with the Platte River caddisfly also appear to be more food-limited than others as these areas have less standing vegetation (Vivian 2011, p. 18). The amount of available food can limit the abundance of shredder species (Roeding and Smock 1989, p. 149), such as the Platte River caddisfly (Vivian 2011, p. 18).

The type locality from which the Platte River caddisfly was described had an intermittent hydroperiod (Whileset al.1999, p. 536). The Platte River caddisfly was not found at four other sloughs near the type locality during the time of the life history study; these sloughs had hydroperiods that differed from that of the type locality—they were thought to be either too ephemeral or permanent for the caddisfly (Whileset al.1999, p. 542; Whiles and Goldowitz 2001, p. 1832; Whiles and Goldowitz 2005, p. 466). Also, the Wild Rose Slough site contains ephemeral, intermittent, and permanent reaches, and the Platte River caddisfly has only been observed in the intermittent (Vivian 2010, pers. obs.) and permanent reaches of the slough (Gelusoet al.2011, p. 1022). In other parts of its range, the Platte River caddisfly has been found in sloughs with more permanent hydroperiods, albeit in lower numbers than in sloughs with intermittent hydroperiods (Vivian 2010, p. 54; Gelusoet al.2011, p. 1022).

The caddisfly occurs in higher densities in intermittent sloughs than in sloughs with permanent hydroperiods. For instance, the type locality and Wild Rose Slough have intermittent hydroperiods (Vivian 2010, pers. obs.) and have supported or currently support the largest known larval densities of the Platte River caddisfly (Whileset al.1999, p. 536; Vivian 2010, pers. obs.; Gelusoet al.2011, p. 1022). Relatively low densities of the caddisfly have been found at other sites that have longer hydroperiods and experience less water level fluctuation (Vivian 2010, p. 54). Thus, it is thought that sloughs with intermittent hydroperiods are ideal for the Platte River caddisfly. Although intermittent wetlands represent ideal Platte River caddisfly habitat, permanent wetlands may become important during and following a drought as sites that support source populations for recolonization following extended dry periods. However, ephemeral wetlands do not remain wet long enough to support the species' lifecycle.

Overall, landscape-level changes in hydrology that result from reservoir construction, river channel diversions, and groundwater withdrawal for irrigation could adversely impact the Platte River caddisfly and its habitat through the loss of water during critical life stages or degradation of its habitat. Since European settlement in the 1850s, the Platte, Loup, and Elkhorn Rivers have all experienced some degree of water development for various purposes; the Platte River has experienced the largest amount of modification of these systems. Starting in the mid-1800s, the tributaries of the Platte River were gradually developed to deliver water for irrigation via main and lateral canals, and eventually larger water storage projects along the main channels of the river were constructed (Eschneret al.1981, pp. 3, 5). Water development projects were implemented to make the region more suitable for agriculture, and more than 7,000 canals were constructed along the river between 1851 and 1930 (Simons and Associates 2000, pp. 5-9). Over-appropriation of water in the Platte Basin became an issue as early as 1876, and dams were constructed to create more reliable supplies of water (Eschneret al.1981, p. 10; Simons and Associates 2000, pp. 7-8).

Several hundred storage reservoirs and six principal dams are present in the Platte River Basin, and together they impound more than 7.6 million acre-feet of water for irrigation (Simons and Associates 2000, p. 8). Each reservoir project contains several miles of associated canals (Simons and Associates 2000, p. 13). Because of dams and diversions along the Platte Basin, over 70 percent of the Platte River flow is estimated to be diverted before it reaches Lexington, Nebraska (Currieret al.1985, p. 120; Sidleet al.1989, p. 91), which is about 48 km (30 mi) upstream of where most Platte River caddisfly populations along the Platte River are found. As a result of this development, the river has been described as one of the most heavily managed river systems in the United States (Simons and Associates 2000, p. 14; LaGrange 2004, 274 15).

The Loup River has also been impacted by water development projects. The Loup Basin includes the North, Middle, and South Loup Rivers, and within the basin there are four mainstem diversion dams (U.S. Bureau of Reclamation (USBR) 2011, entire). The largest diversion dam, the Loup Diversion Dam, diverts around 69 percent of the Loup River flow away from the main channel for a distance of 35 miles in Nance and Platte Counties in Nebraska (Loup Power District and HDR Engineering 2008, p. 4-39). Each diversion dam has several miles of associated lateral canals to divert water to irrigated farmland (USBR 2011, entire). Also, three impoundments are present along tributaries of the Loup River Basin (Loup Power District and HDR Engineering 2008, pp. 3-5), but the system lacks mainstem dams. The Elkhorn River is generally free of impoundments and diversions (LaGrange 2004, p. 21; Petersonet al.2008, p. 5).

Dams and diversion projects are known to result in changes in hydrological, geophysical, and ecological characteristics of river systems (Simons and Associates 2000, p. 15; Schrammet al.2008, pp. 237-238). Dams and diversions dampen the natural flow regime and change the hydrology of river systems, contribute to the downcutting and degradation of the river bed, reduce the amount of sediment flowing downstream, and reduce the amount of water reaching floodplain wetlands (Kingsford 2000, p. 109; Bowenet al.2003, p. 809). These changes affect the ability of managed river systems to remain in a state of dynamic equilibrium, which contributes to the creation and maintenance of a diversity of habitats along a river's floodplain (Bowenet al.2003, p. 809). Water development projects may ultimately cause a river to become disconnected from its floodplain (Bowenet al.2003, p. 809) and reduce the ability of rivers to continually inundate and create new backwater habitats via peak flows (Schrammet al.2008, pp. 237-238).

As a result of reduced flow through the Platte River system, the main channel of the Platte River narrowed by about 65 to 80 percent between the mid-19th century and 1969 (Williams 1978, p. 8; Eschneret al.1981, p. 45) and further narrowed by up to 25 percent between 1970 and 1999 (Murphyet al.2004, p. 102). Channel narrowing has resulted in a reduction in wetland habitat along the Platte River through a drying of adjacent sloughs. Between 1938 and 1982, an estimated 45.2 percent of wet meadow habitat along the central Platte River was lost (Sidleet al.1989, pp. 98-99), and this corresponded to a 53.4 percent reduction in active channel width during the same time period (Peakeet al.1985, entire; Sidleet al.1989, pp. 98-99). The drying of linear slough depressions along the river also facilitated the development of row crops along what used to be wet bottomlands (Currieret al.1985, p. 113).Many wetlands were initially converted to cropland through wetland draining via ditches and land leveling (Currieret al.1985, p. 113). Wetland losses and channel shrinkage data for the Loup River are currently unavailable; however, wetland losses have likely occurred concurrent with the narrowing of the river channel downstream of diversion projects.

Historically, channel narrowing on the Platte and Loup River systems resulting from water development likely resulted in direct losses of suitable Platte River caddisfly habitat prior to the species' discovery in the late-1990s. During recent survey efforts, the Platte River caddisfly was not found between Hershey and Elm Creek, Nebraska, despite 24 surveys being conducted in this reach (Vivian 2010, p. 50). We do not know if the caddisfly ever occurred in this stretch of river, but it is present upstream and downstream of Hershey and Elm Creek, Nebraska, respectively (Vivian 2010, p. 50), and this stretch is likely one of the most dewatered and incised (disconnect of a river from its floodplain as a result of a decline in river bed elevation) portions of the Platte River (Murphyet al.2004, p. 56). Since the species was first described in 2000, no known population losses have occurred as a result of channel narrowing and subsequent wetland drying.

Aside from the draining of adjacent wetlands, channel narrowing has resulted in an increase in woody vegetation cover along the Platte River (Johnson 1994, entire). Downstream of Kearney, Nebraska, channel narrowing continues to reduce the amount of active channel area, and the amount of forest cover continues to increase (Murphyet al.2004, p. 95), despite no new impoundments having been constructed in the Platte basin since 1956 (Johnson 1994, pp. 77-78). The establishment and proliferation of woody vegetation along the river acts to stabilize the river and can further contribute to channel narrowing through the trapping of sediments (Friedmanet al.1996, p. 341). Meanwhile, an increase in forest cover is not thought to have an adverse impact on the Platte River caddisfly, because most known caddisfly populations are found in forested wetlands, and some forested sloughs support relatively high larval densities of the Platte River caddisfly (Vivian 2010, p. 64). It is unlikely that any future increases in forest cover will adversely affect the Platte River caddisfly.

Aside from channel narrowing, impoundments and diversions can contribute to the downstream degradation of river systems, and these projects can have lasting impacts. Impacts to the Platte River resulting from past water development projects, which may affect the caddisfly, are ongoing. For instance, reduced sediment loads resulting from impoundments that block the passage of sediments and water discharges below diversion returns and dams are known to impact river systems and result in channel bed degradation. The North Platte River historically provided the majority of the sandy sediment to the Platte River system, but the amount of sediment inputs to the river greatly declined with the closing of the mainstem dams on the North Platte River (Murphyet al.2004, p. 101). Near Overton, Nebraska, the Johnson-2 (J-2) diversion return releases sediment-free water into the Platte River and creates localized scour and an additional sediment imbalance.

As a result of impoundments and diversion returns, less sediment flows into the Platte River than flows out, and this contributes to the erosion and a lowering of elevation of the river bed (Murphyet al.2004, p. 101). Erosion may also result from a coarsening of sediments in the river, which is a result of coarser sediment being supplied from the South Platte River as opposed to the fine sands that used to come from the North Platte River (Murphyet al.2004, p. 115). Erosion results from a change in sediment size, because smaller sediment is transported downstream more quickly than coarser sediments (Murphyet al.2004, p. 119). This downcutting (or incision) further narrows the active channel and acts to drain adjacent floodplain wetlands (Murphyet al.2004, p. 129). Channel incision resulting from the sediment imbalance along the Platte River is thought to be largely complete upstream of Kearney, Nebraska, but has only slightly affected the river between Kearney and Grand Island, Nebraska, indicating that the trend of degradation is moving downstream (Murphyet al.2004, pp. 113, 129). Channel incision and degradation resulting from the sediment imbalance in the Platte River and a coarsening of sediments is anticipated to take decades to be fully complete (Murphyet al.2004, pp. 128-130).

The effects of channel degradation and its impacts on the Platte River caddisfly and its habitat can be observed downstream of the J-2 return. Diversion returns, like the J-2 return, that put clear water directly into the main channel of the Platte River, can contribute to the downcutting of the river bed and subsequent draining of adjacent floodplain wetlands. For instance, in 2010, surveys for the Platte River caddisfly were conducted downstream of the J-2 return near Overton, Nebraska, at Dogwood Wildlife Management Area (WMA). Within the WMA, several linear depressions were observed, and these areas were dry but showed signs of past beaver (Castor canadensis) activity, indicating that the area had once supported slough habitat (Vivian 2010, p. 51). Given that the depressions were dry, habitat for the caddisfly was absent (and so was the species) and, therefore, it seems that the downcutting of the Platte River near Overton, Nebraska, has contributed to the loss of potentially suitable caddisfly habitat at Dogwood WMA.

The effects of the J-2 return can be observed up to 29 km (18 mi) downstream of the return, although these effects are most pronounced closest to the return (Murphyet al.2004, p. 142). Between 1989 and 2002, the Platte River bed depth eroded 1.8 meters (6 feet) immediately downstream of the J-2 return, and eroded 0.76-meter (2.5 feet) 29 km (18 mi) downstream from the return during the same time period (Murphyet al.2004, p. 106). At Grand Island, Nebraska, the river bed eroded 0.27-meter (0.89-foot) between 1933 and 1995 (Murphyet al.2004, p. 113). It is anticipated that the process of incision as a result of the J-2 return will continue downstream all the way to Grand Island, but it is expected to progress slowly (Murphyet al.2004, pp. 113-114). For instance, the river could incise by 0.60-meter (2 feet) from 1940 bed elevation levels within 100 years, 48 km (30 mi) downstream of the return. However, these same impacts are expected to take 400 years to affect the area 100 km (60 mi) downstream of the return (Murphyet al.2004, p. 114), an area where seven of the 35 known Platte River caddisfly populations occur. This incision could further narrow the central Platte River and contribute to the draining of adjacent wetlands and sloughs occupied by the Platte River caddisfly.

It is likely that channel incision has contributed to a loss in available Platte River caddisfly slough habitat in the past and could adversely affect the remaining sloughs on the central Platte River (Lexington, Nebraska to Chapman, Nebraska, where several populations of the Platte River caddisfly occur) in the future. The impacts of channel degradation on Platte River caddisfly habitat are best demonstrated by the effects observed at Dogwood WMA andat the Crane Trust on Shoemaker and Mormon Islands. Harner and Whited (2011, pp. 17-18; Harner 2012, pers. comm.) demonstrated that although there was two times more river discharge in the Platte River in 1999 than in 1951, less slough habitat was available at the Crane Trust in 1999 than was present in 1951. Between 1951 and 1999, the amount of available slough habitat declined by 0.3-hectare (0.8-acre) at Wild Rose Slough (which is deeper and more entrenched, resulting in less surface area lost) on Shoemaker Island and 3.6 hectares (8.8 acres), or about 28 percent, at the type locality on Mormon Island (Harner and Whited 2011, pp. 17-18). Declines in the amount of slough habitat were attributed to channel incision of the Platte River, or a drop in the groundwater table, or both, as land leveling has not occurred along the stretch of the river owned by the Crane Trust. These results demonstrate that even though river discharge in 1999 was greater than in 1951, more water in the Platte River does not necessarily mean that the floodplain will be inundated enough by elevated groundwater to support sloughs where the Platte River caddisfly occurs (Harner and Whited 2011, p. 23).

Currently, the Crane Trust area supports the highest known densities of the Platte River caddisfly (Whileset al.1999, p. 537; Vivian 2010, p. 47; Gelusoet al.2011, p. 1022) and is one of the largest remaining stretches of intact prairie in the Central Platte Valley. However, although the Crane Trust protects the parcel where the caddisfly occurs, this area is not buffered from the effects of upstream water development and nearby groundwater pumping (Harner and Whited 2011, pp. 23-24; Harner 2011, pers. comm.). The documented decline in the amount of available slough habitat between 1951 and 1999 (Harner and Whited 2011, entire) illustrates that effects of past and current degradation to the river channel are ongoing even though there have been no major water projects implemented on the Platte River since 1956 (Johnson 1994, p. 78). If left unchecked (Murphyet al.2004, p. 114), future channel degradation could eventually result in as much as a total loss of Platte River caddisfly habitat at the Crane Trust and other nearby sloughs. For instance, Harner and Whited (2011, p. 14) demonstrated that groundwater declines greater than 0.5-meter (1.5-2.0 feet) from 1999 levels could result in slough drying at the type locality in years with similar precipitation and river discharge (Harner and Whited 2011, p. 20).

Although Harner and Whited (2011) demonstrated an ongoing trend in channel degradation within the central Platte River near the Crane Trust at Alda, Nebraska, the Platte River caddisfly is still present at the type locality and Wild Rose Slough more than 10 years following 1999 (year of reference used in the study). There are also extant Platte River caddisfly populations upstream of the Crane Trust, where the effects of channel degradation are more pronounced, such as near Elm Creek, Nebraska, where the channel bed incised by 0.76-meter (2.5 feet) between 1989 and 2002 (Murphyet al.2004, p. 106). Meanwhile, the type locality and Wild Rose Slough occur more off channel than the forested sloughs adjacent to the river channel and may be less buffered from the effects of channel incision, because hydroperiod is known to decrease with increasing distance from the river channel (Whileset al.1999, p. 533). Therefore, habitat loss at the Crane Trust likely does not represent the norm throughout the range of the Platte River caddisfly.

If left unchecked, future channel degradation could result in future losses in slough habitat and subsequent extirpation of the Platte River caddisfly from the central Platte River. However, various programs and entities are acting to maintain current habitat conditions on the central Platte River. The central Platte River is actively managed by several organizations to benefit endangered (E) and threatened (T) species (whooping crane (Grus americana) (E), interior least tern (Sterna antillarum athalassos) (E),piping plover (Charadrius melodus) (T), and pallid sturgeon (Scaphirhynchus albus) (E)) that depend on an open and braided river system. One such organization is the Headwaters Corporation, which is the nongovernmental organization responsible for overseeing the Platte River Recovery Implementation Program (PRRIP) (discussed more below and under Factor D).

PRRIP was established in 2006, by an agreement between the Bureau of Reclamation, the Service, and the States of Colorado, Wyoming, and Nebraska to manage Platte River flows and habitat to meet the needs of endangered and threatened species that use the Platte River. For instance, PRRIP plans to clear and lower vegetated islands in the river to create a more open channel to benefit endangered species, and this action would increase the amount of sediment in the river (Murphyet al.2004, p. 143; U.S. Department of the Interior (DOI) 2006, p. 5-60). PRRIP also seeks to offset the sediment imbalance in the river by adding sand to the central Platte River (DOI 2006, p. 5-55) and release pulse flows to maintain present channel conditions (DOI 2006, p. 3-11). Outside PRRIP, some work of removing riparian vegetation has already been executed by organizations such as the Nebraska Public Power District (Kinzelet al.2006, entire). Other entities, such as the Partners for Fish and Wildlife Program (PFW), are actively restoring sloughs along the central Platte River to benefit wildlife, and these areas could eventually provide suitable habitat for the Platte River caddisfly. Ongoing efforts to maintain and improve current conditions along the central Platte River should help stem the ongoing degradation of the river and reduce the amount of potential losses of slough habitat throughout the Platte River portion of the species' range.

As mentioned previously, water development on the Loup and Elkhorn Rivers has not been as extensive as it has along the Platte River. While there are diversions in place along the Loup River, these diversions have not resulted in extensive channel incision and degradation as has been observed along the Platte River. This can be demonstrated by the lack of vegetation encroachment onto the active river bed. Channel narrowing downstream of diversion projects on the Loup River Basin has likely resulted in a loss of slough habitat in the past. However, the Platte River caddisfly is present immediately upstream of Kent Diversion Dam, and the species is present immediately downstream of the Loup Diversion Dam. The populations in the vicinity of these projects appear secure, because there appears to be ample slough habitat to support the caddisfly at these sites (Vivian 2010, pers. obs.). Potentially suitable habitat that has not been surveyed is also present downstream of all four main diversion projects in the Loup River Basin (Vivian 2012, pers. obs.). Meanwhile, no large-scale projects on the Loup or Elkhorn Rivers are planned. Because of ongoing efforts to maintain present channel conditions in the central Platte River, which is the most degraded portion of the range of the Platte River caddisfly, and because of a general lack of channel degradation on the Loup and Elkhorn Rivers, we conclude that channel degradation does not pose a threat to the Platte River caddisfly.

An altered hydrograph (graph of stream flow through time) can resultfrom dams and diversion projects. For instance, dams impound water and reduce the amount of water flowing through a river system. Diversion projects can result in a changed hydrograph by altering the timing of flows through a river system and can reduce the amount of water flowing downstream. Historically, the Platte River received a late-spring rise as a result of runoff from Rocky Mountain snowmelt, and water levels then receded through the summer months, with the river nearly drying completely in some years (Eschneret al.1981, pp. 19-20; Simons and Associates 2000, p. 8). Because of water development projects, primarily dams, the historical hydrologic regime of the Platte River has been altered. For instance, at North Platte, Nebraska, peak flows declined from 20,000 cubic feet per second (cfs) in the late 1800s to less than 5,000 cfs after 1940 (Simons and Associates 2000, p. 16). Dams are also known to augment base flows in a river system, meaning that some floodplain wetlands never go dry (Kingsford 2000, p. 111). Following water development on the Platte River, periods of no or little flow have decreased (Simons and Associates 2000, p. 44). A reduction in natural periods of low flow could impact the intermittency of sloughs where the Platte River caddisfly occurs by increasing the permanency of water in certain areas. Despite the potential for sloughs along the Platte and Loup Rivers to be more permanent, the Platte River caddisfly has presumably existed with the presence of dams on the landscape for over 100 years. The species also occurs in permanent sloughs, and these areas could become important source populations for other intermittent wetlands following extended dry periods or drought. Wetlands that were historically intermittent may have become ephemeral wetlands unsuitable for the caddisfly concurrent with water development. However, we have no information to indicate that this has occurred since the species was described in 2000.

At this time, there is no available information to indicate that an altered hydrograph is adversely affecting any populations of the Platte River caddisfly or has resulted in population losses throughout its range. Therefore, we do not consider a changed hydrograph to pose a threat to the Platte River caddisfly.

Along the Platte River, changes in hydrology have contributed significantly to the encroachment of woody and exotic vegetation onto what used to be the active river bed (Currieret al.1985, p. 119; Johnson 1994, p. 47). In 2002, several areas of the Platte River went completely dry for 2 months because of drought, and in 2003, low to zero flows were recorded for extended periods of time within the Big Bend reach of the Platte (80-mile stretch of the Platte River between Overton and Chapman, Nebraska) (Service 2006, p. 113). During this time, dense invasive vegetation grew within the Platte River channel as a result of lower flows.Phragmites australis(common reed orPhragmites) andPhalaris arundinacea(reed canarygrass), two non-native, invasive species, have proliferated on previously barren sandbars and in wetlands along the Platte River in the last decade. Historically, encroaching vegetation would have been washed away by ice scour, or high spring flows (now dampened by water development), or both (Service 2006 p. 163), but active removal is now required to keep invasive species in check. Invasive species have not proliferated on the Loup and Elkhorn Rivers as much as on the Platte. OnlyP. arundinaceahas been observed in sloughs along the Loup River and in lower abundances than in sloughs along the Platte River.

In the United States, there are introduced and native varieties ofPhragmites australis,and the introduced and hybridized forms have become highly invasive in several States, including Nebraska (NRCS 2002, entire; Blossey 2003, entire).P. australiscan be up to 15 feet tall and quickly crowds out native wetland species once established (Michigan Department of Environmental Quality 2011, entire). There are also native and introduced ecotypes ofPhalaris arundinacea,and the species can be aggressive and invade wetlands.P. arundinaceahas been observed to form dense, monotypic stands and impenetrable mats of stems and leaves and crowd out native plant species (Wisconsin Department of Natural Resources 2007, entire).P. arundinaceawas introduced from Europe for agricultural use (Maureret al.2003, p. 16) and may be the most pervasive emergent plant in wetlands in the Midwest (Spyreaset al.2010, p. 1254). BothP. australisandP. arundinaceahave likely spread along the Platte River as a result of deliberate introductions and changes in hydrology (Andersenet al.2004, p. 787; Strayeret al.2006, p. 649).

BothPhragmites australisandPhalaris arundinaceahave been observed in sloughs where the Platte River caddisfly occurs; however,P. arundinaceais more abundant and more often encountered in these wetlands (Vivian 2010, pers. obs.). These invasive plant species have been observed at 24 out of 35 sites with the caddisfly (Vivian 2011, pers. obs.) and appear to have degraded habitat at five sites with the caddisfly along the Platte River. At three sites,P. arundinaceaappears to have grown thick enough to completely dry out slough margins and to have reduced the amount of available Platte River caddisfly habitat at these sites (Vivian 2009, pers. obs.).P. australisis or was the dominant vegetation present at two sloughs where the caddisfly occurs when these areas were surveyed (Vivian 2009, pers. obs.); this plant has potentially reduced the habitat quality at these sites, as these sites support the lowest known densities of the Platte River caddisfly (Vivian 2010, p. 64.). Nonetheless, no extirpations have been observed as a result of displacement by invasive species, and work is underway along the central Platte River to control and reduce the spread ofP. australis(The Nature Conservancy 2011, entire). In other sloughs that support exotic vegetation, there is no evidence to suggest thatP. australisorP. arundinaceaare encroaching to the point where habitat quality is being reduced or will be reduced in the near future. Because invasive species appear to be impacting the Platte River caddisfly at only a small number of sites throughout its range, we do not consider invasive plant species to pose a threat to the Platte River caddisfly.

Following dam construction in the Platte Basin, irrigation demands were met through the pumping of groundwater (Eschneret al.1981, p. 10), particularly along the central Platte River (Currieret al.1985, p. 87). The central Platte River remains the most heavily irrigated region in Nebraska, with an average of 2 to 16 registered groundwater wells per mile (University of Nebraska at Lincoln, School of Natural Resources (UNL-SNR) 2011a, entire). As of 2008, there were 1.3 million acres of irrigated cropland within the Loup Basin (Loup Power District and HDR Engineering 2008, p. 3-1). Throughout most of the Loup and Elkhorn Basins, there are up to 4 registered irrigation wells per mile, but there can be up to 16 wells per square mile in the Loup Basin (UNL-SNR 2011a, entire).

Groundwater pumping can result in a lowering of the water table and contribute to subsequent wetland drying and loss (van der Kamp and Hayashi 1998, p. 51; LaGrange 2004, p. 13). It is possible that pumping groundwater forirrigation contributed to some Platte River caddisfly habitat loss historically throughout the species' range, particularly in the central Platte River (Big Bend reach) where irrigation dominates the valley (Currieret al.1985, p. 87). However, available data on monitored groundwater levels do not indicate that this has occurred or is occurring on a wide scale throughout the range of the Platte River caddisfly.

Along the eastern portion of the central Platte River (east of Buffalo County line), groundwater levels in some isolated areas near the river declined 1.5 to 3.0 meters (5 to 10 feet) between pre-development (1950 or later for some parts of Nebraska) (McGuire 2011, pp. 1, 4) and spring2011 (UNL-SNR 2011b, entire). The remainder of the groundwater table near the Platte River experienced little to no change or an increase (UNL-SNR 2011b, entire). Throughout the entire central Platte region and near the river, the groundwater table declined 0.3 to 1.5 meters (1 to 5 feet) between spring 2001 (species described in 2000) and spring 2011 (UNL-SNR 2011c, entire) but increased 0.6 to 1.5 meters (2 to 5 feet) between spring 2006 and spring 2011 (UNL-SNR 2011d, entire). The groundwater level declines observed between 2001 and 2011 may be attributed to drought conditions in Nebraska during the first half of the 2000s (see Climate Change, below).

Aside from a few small, isolated areas where groundwater levels declined close to the Loup River, between 1950 and 2011, groundwater levels increased by at least 1.5 meters (5 feet) throughout most of the Loup and part of the Elkhorn Basins (UNL-SNR 2011b, entire). Elsewhere in the Elkhorn Basin, there was no change in observed groundwater levels between 1950 and 2011 (UNL-SNR 2011b, entire). It is unlikely that observed increases in the groundwater table along the Loup and Elkhorn Rivers have contributed to losses in the amount of slough habitat available to the caddisfly.

Where groundwater levels have dropped within the range of the Platte River caddisfly, it is possible that a loss in slough habitat has occurred through the loss of inundated wetland acres. However, since the species was described, drops in the groundwater table due to pumping are not known to have resulted in extirpations of any caddisfly populations. Also, the amount of loss in slough habitat is likely limited, because the groundwater table dropped in only three isolated areas within the range of the caddisfly between 1950 and 2011 (UNL-SNR 2011b, entire). Only one of these areas overlaps with extant Platte River caddisfly populations, and this area is along the central Platte River. The other two areas near where groundwater levels have declined since pre-development support slough habitat that has not yet been surveyed for the caddisfly.

There is the potential for ongoing and future groundwater withdrawals to adversely impact the Platte River caddisfly and its habitat in the future, particularly given the recent increase in demand for grain. For instance, in the Lower Loup Natural Resources District (LLNRD), which encompasses the Loup River and its tributaries upstream of Columbus, Nebraska, to the west end of Loup and Custer Counties, 10,000 additional acres were approved to be added to the amount of irrigated acres between 2010 and 2013 (Lower Loup Natural Resources District 2011, entire), and so the groundwater table in that region may see declines with the increase in irrigation. Within the Central Platte Natural Resources District (CPNRD), 2,500 new acres were opened for development in 2012 downstream of Chapman, Nebraska. Future declines in the amount of slough habitat on the Platte, Loup, and Elkhorn Rivers associated with the increased demand for groundwater usage may occur.

Although the amount of slough habitat available to the caddisfly has the potential to decline in the future concomitant with the increase in grain production across at least some of the species' range, existing regulations are likely to limit the extent to which this can occur. Along most of the central Platte River, we have determined that groundwater sources are relatively secure, because, presently, there is a moratorium on new groundwater wells that pump more than 50 gallons per minute, and no new well permits can be issued unless the amount of consumptive water use is offset (retired elsewhere in the basin) (CPNRD 2011, pp. 3-4). Therefore, current conditions are not anticipated to worsen with respect to groundwater pumping in the central Platte Basin, which is considered to be the most degraded portion of the species' range. Also, because the sloughs along the Platte River are closely tied to surface water flows within 0.8 km (0.5 mi) of the river (Hurr 1981, p. H7), efforts to increase shortages to target flows in the Platte River under the PRRIP should maintain current conditions in sloughs along the river. Elsewhere in the Loup and Elkhorn Basins, groundwater and surface water resources are being managed by Nebraska's natural resources districts, and by State law, these areas cannot exceed the fully appropriated designation.

As part of Nebraska State law LB 962, passed by the State legislature in 2004, groundwater well permits and surface water permits are carefully managed so that river flows do not reach the over-appropriated designation, because it has been recognized that surface flows are tied to groundwater levels near the river and vice versa. Nebraska State law requires that there be a balanced use of ground and surface waters in Nebraska to ensure the long-term sustainability of these supplies (Petersonet al.2008, p. 2). Limited numbers of acres are being allowed for well drilling on an annual basis in the Loup and Elkhorn Basins. However, stays are placed on the construction of new wells once a river basin is deemed fully appropriated (Ostdiek 2009, p. 2). A fully appropriated designation ((Neb. Rev. Stat. § 46-713(3) (Reissue 2004, as amended)) means that based on current groundwater and surface water usage, average streamflows are insufficient to meet the long-term demands within a basin (Petersonet al.2008, p. 5). Following any fully appropriated designation, the Nebraska Department of Natural Resources (NDNR) and applicable natural resource district must create an integrated management plan to achieve a sustainable balance between water demands and supplies (Petersonet al.2008, p. 5). If an area becomes over-appropriated, State law requires that the applicable natural resource district work with its stakeholders on returning the basin to a fully appropriated status (Ostdiek 2009, p. 2).

Since the Platte River caddisfly was described in 2000, no information has become available to indicate that any net loss in slough habitat has occurred as a result of groundwater pumping. At this time, the Service does not have data showing that the quantity of water has been lowered or that the current water withdrawals are impacting the Platte River caddisfly habitat or will impact the Platte River caddisfly in the near future. Declines in the groundwater table due to drought resulted in two localized caddisfly extirpations; however, the species is now found again at the type locality, and the groundwater table has since rebounded in that area. If habitat loss has occurred, we estimate that the amount has been negligible, because groundwater declines between 1950 and 2011 have occurred only within a small portion of the species' range. The Platte River caddisfly is extant in the area of the Platte River where the largest documented drops in the groundwater table have occurred. The species is also present in the areaof the Platte River where there is the highest density of registered irrigation wells (UNL-SNR 2011a, entire). Elsewhere, groundwater levels have increased, possibly because of seeps that parallel the river channel (Murphyet al.2004, p. 47) and groundwater recharge from lateral canals (Petersonet al.2008, p. 13), and, therefore, habitat losses cannot be attributed to a declining aquifer.

Current moratoria in the Platte Basin, which includes a moratorium on new surface water diversions (NDNR 2008, entire), should prevent current conditions from worsening throughout the most degraded portion of the species' range along the central Platte River. Current State law and management by the State's various natural resources districts on the Loup and Elkhorn Rivers should maintain the groundwater table at sustainable levels in those areas. For instance, the Loup and Elkhorn River Basins are subject to limited surface water appropriations, because the NDNR has to ensure adequate flows exist in the Lower Platte Basin for endangered species, such as the pallid sturgeon (NDNR 2006, p. E-11). Overall, we have determined that groundwater withdrawal does not pose a threat to the species. However, additional stress from water demand is likely to be placed on Nebraska's river systems in the future as a result of climate change and projected increases in floods and droughts (discussed below).

Global climate change is a concern, because it has the potential to reconfigure the spatial distribution of species and their habitats worldwide throughout the 21st century and beyond. Our analyses under the Act include consideration of ongoing and projected changes in climate. The terms “climate” and “climate change” are defined by the Intergovernmental Panel on Climate Change (IPCC). The term “climate” refers to the mean and variability of different types of weather conditions over time, with 30 years being a typical period for such measurements, although shorter or longer periods also may be used (IPCC 2007a, p. 78). The term “climate change” thus refers to a change in the mean or variability of one or more measures of climate (e.g., temperature or precipitation) that persists for an extended period, typically decades or longer, whether the change is due to natural variability, human activity, or both (IPCC 2007a, p. 78).

Scientific measurements spanning several decades demonstrate that changes in climate are occurring, and that the rate of change has been faster since the 1950s. Examples include warming of the global climate system, and substantial increases in precipitation in some regions of the world and decreases in other regions (IPCC 2007a, p. 30; Solomonet al.2007, pp. 35-54, 82-85). Results of scientific analyses presented by the IPCC show that most of the observed increase in global average temperature since the mid-20th century cannot be explained by natural variability in climate, and is “very likely” (defined by the IPCC as 90 percent or higher probability) due to the observed increase in greenhouse gas (GHG) concentrations in the atmosphere as a result of human activities, particularly carbon dioxide emissions from use of fossil fuels (IPCC 2007a, pp. 5-6 and figures SPM.3 and SPM.4; Solomonet al.2007, pp. 21-35). Further confirmation of the role of GHGs comes from analyses by Huber and Knutti (2011, p. 4), who concluded it is extremely likely that approximately 75 percent of global warming since 1950 has been caused by human activities.

Scientists use a variety of climate models, which include consideration of natural processes and variability, as well as various scenarios of potential levels and timing of GHG emissions, to evaluate the causes of changes already observed and to project future changes in temperature and other climate conditions (e.g., Meehlet al.2007, entire; Gangulyet al.2009, pp. 11555, 15558; Prinnet al.2011, pp. 527, 529). All combinations of models and emissions scenarios yield very similar projections of increases in the most common measure of climate change, average global surface temperature (commonly known as global warming), until about 2030. Although projections of the magnitude and rate of warming differ after about 2030, the overall trajectory of all the projections is one of increased global warming through the end of this century, even for the projections based on scenarios that assume that GHG emissions will stabilize or decline. Thus, there is strong scientific support for projections that warming will continue through the 21st century, and that the magnitude and rate of change will be influenced substantially by the extent of GHG emissions (IPCC 2007a, pp. 44-45; Meehlet al.2007, pp. 760-764, 797-811; Gangulyet al.2009, pp. 15555-15558; Prinnet al.2011, pp. 527, 529). (See IPCC 2007b, p. 8, for a summary of other global projections of climate-related changes, such as frequency of heat waves and changes in precipitation. Also see IPCC 2011 (entire) for a summary of observations and projections of extreme climate events.)

Various changes in climate may have direct or indirect effects on species. These effects may be positive, neutral, or negative, and they may change over time, depending on the species and other relevant considerations, such as interactions of climate with other variables (e.g., habitat fragmentation) (IPCC 2007a, pp. 8-14, 18-19). Identifying likely effects often involves aspects of climate change vulnerability analysis. Vulnerability refers to the degree to which a species (or system) is susceptible to, and unable to cope with, adverse effects of climate change, including climate variability and extremes. Vulnerability is a function of the type, magnitude, and rate of climate change and variation to which a species is exposed, its sensitivity, and its adaptive capacity (IPCC 2007a, p. 89; see also Glicket al.2011, pp. 19-22). There is no single method for conducting such analyses that applies to all situations (Glicket al.2011, p. 3). We use our expert judgment and appropriate analytical approaches to weigh relevant information, including uncertainty, in our consideration of various aspects of climate change.

As is the case with all stressors that we assess, even if we conclude that a species is currently affected or is likely to be affected in a negative way by one or more climate-related impacts, it does not necessarily follow that the species meets the definition of an “endangered species” or a “threatened species” under the Act. If a species is listed as endangered or threatened, knowledge regarding the vulnerability of the species to, and known or anticipated impacts from, climate-associated changes in environmental conditions can be used to help devise appropriate strategies for its recovery.

The effects of climate change, such as an increase in the global average air surface temperature since 1970, are already being felt in North America and around the world (U.S. Global Change Research Program (USGCRP) 2009, pp. 9, 17). In the Rocky Mountains and Northern Hemisphere, there has been a decrease in overall snowpack cover over the past 100 years (IPCC 2007, p. 30), and the proportion of precipitation falling as snow is decreasing (USGCRP 2009, p. 43). More precipitation now falls in the form of extreme rain events (Rieman and Isaak 2010, p. 4). A decrease in annual snowpack is projected to lead to earlier spring snowmelt and runoff, reduced runoff and stream flow, decreased recharge ofaquifers, an increase in drought frequency and intensity, and shorter wetland hydroperiods (USGCRP 2009, p. 45; Johnsonet al.2010, p. 137; Rieman and Isaak 2010, pp. 4, 6, 8). Flooding risk is also projected to increase in association with warmer winters and earlier snowmelts (Saunders and Maxwell 2005, p. 1), and summer flows are expected to be lower (USGCRP 2009, p. 46). Decreases in the amount of snowfall and earlier snowmelt in the Rocky Mountains are most likely to affect the sloughs along the Platte River, because its flows are tied to Rocky Mountain snowmelt, while Loup and Elkhorn River flows are tied to the Ogallala Aquifer and local precipitation events.

In the Great Plains, the average annual temperature has increased by 0.83 °C (1.5 °F) since the 1970s and is expected to increase 2.5 °C (4.5 °F) by 2050 (USGCRP 2009, p. 123) and between 4.2 °C (8 °F) and 5.0 °C (9 °F) by the 2080s across the range of the Platte River caddisfly (The Nature Conservancy 2007, entire). Should GHG continue at the current rate, average annual precipitation is expected to remain steady or decrease by 5 percent from today's levels across the range of the Platte River caddisfly by 2050 (The Nature Conservancy 2007, entire).

Between the 1930s and 2011, average maximum temperatures have remained steady in the Lower Platte Basin (downstream of the North Platte/South Platte confluence), while there has been an increase in average maximum temperatures in the Upper Platte Basin (upstream of the confluence) for the same time period (Stamm 2012, pers. comm.). During the same time period, there has been a wetting trend in the Lower Platte Basin and a drying trend in the Upper Platte Basin (Stamm 2012, pers. comm.). Meanwhile, average minimum temperatures increased across the entire Platte Basin between the 1930s and the decade ending in 2011 (Stamm 2012, pers. comm.). Available models for the Loup and Elkhorn River Basins demonstrate similar trends (http://www.climatewizard.org/,accessed June 25, 2012).

Should worldwide GHG emissions remain the same as today's levels, starting in 2030, average temperatures are projected to increase dramatically across the entire Platte Basin and continue increasing through at least 2050, and precipitation is projected to remain steady or decrease slightly compared to the decade ending in 2011 (http://www.climatewizard.org/,accessed June 25, 2012). Average winter, spring, and fall temperatures are projected to increase by 1.0-2.5 °C (2.7-4.5 °F), and summer temperatures will likely increase by 3.5-4.0 °C (6.3-7.2 °F) by 2050 when compared to the decade ending in 2011 (http://www.climatewizard.org/,accessed June 25, 2012).

Compared to the decade ending in 2011, by 2030, fall and winter precipitation is projected to remain steady or slightly decrease; spring precipitation could decline by 20-30 mm, and summer precipitation is projected to decrease by 50-60 mm for the Lower Platte Basin (http://www.climatewizard.org/,accessed June 25, 2012). Conditions are also expected to become hotter and drier in the Upper Platte overall (http://www.climatewizard.org/,accessed June 25, 2012). Because the sloughs along the Platte River receive snowmelt from the Rocky Mountains (Williams 1978, p. 1) and there is anticipated to be reduced snowpack, sloughs along the Platte River are likely to be more vulnerable to drying than sloughs along the Loup and Elkhorn Rivers during droughts.

Although some models indicate parts of the range of the Platte River caddisfly could experience wetter winters and springs, projected increases in temperature could negate the effects of increased precipitation through increases in evaporation and transpiration (evaporation of water from plant leaves), particularly in the summer months (Sorensonet al.1998, pp. 344-345, 355-356; Johnsonet al.2010, p. 128). Increased evapotranspiration (combined effect of evaporation and transpiration) is expected to create drier conditions in the northern Great Plains, thereby increasing the frequency and severity of droughts (Sorensonet al.1998, pp. 344-345; USGCRP 2009, p. 126). Overall, by 2030, the entire area will likely be hotter and drier compared to the decade ending in 2011 (Stamm 2012, pers. comm.). A hotter and drier climate represents the worst-case scenario for the Platte River caddisfly.

The Great Plains system is known for its extensive inter-annual climate variability (Ojimaet al.1999, p. 1445), and episodic floods and droughts are characteristic of prairie streams (Doddset al.2004, pp. 205-206) where the Platte River caddisfly occurs. Species found in Great Plains aquatic systems and in intermittent waters, such as the Platte River caddisfly, are well-suited to survive these disturbance events and environmental extremes (Lytle 2002, pp. 370, 371). However, disturbances that occur outside the time when such events normally occur could cause mortality to species such as the Platte River caddisfly.

Despite the projected increase in the frequency of droughts, projected increase in temperature, and projected decrease in hydroperiod length, the Platte River caddisfly presumably survived historical drought periods, particularly through the Dust Bowl (1930s). In 2004, following a dry spring, the type locality for the caddisfly was dry by early April, and adults were not found at that site in the fall of 2004, despite consistent emergence in the 7 years prior (Goldowitz 2004, p. 8). Platte River caddisfly adults were also not observed during surveys between 2007 and 2009 (Riens and Hoback 2008, p. 1; Vivian 2010, p. 48). In 2007 and 2009, the Platte River caddisfly was not observed at one site near Shelton, Nebraska, following the drought in central Nebraska in the early 2000s, and this site is still presumed to be extirpated (Riens and Hoback 2008, p. 1; Vivian 2010, p. 48). Following wetter years in 2008 and 2009, the caddisfly was found at the type locality in 2010 (Gelusoet al.2011, p. 1023), indicating the species has the ability to recolonize suitable habitats following disturbance events. Alternatively, Platte River caddisfly population levels could have decreased to undetectable levels and then rebounded following wetter conditions, as it is easy to miss individual adults when conducting surveys in the autumn (Harner 2012, pers. comm.). It is unknown if the species has recolonized the site near Shelton, Nebraska.

In normal years, the Platte River caddisfly is able to withstand normal summer dry periods through aestivation (Whileset al.1999, p. 542). The burial behavior observed during the aestivation period in the Platte River caddisfly lifecycle likely protects the species against heat and desiccation (Gelusoet al.2011, p. 1024), and affords the species added protection during extended droughts. Furthermore, the relatedIronoquia punctatissima(no common name) has been found to lay its eggs in a gelatinous matrix on a dry streambed with the larvae hatching once waters return (Clifford 1966, entire). It is unknown how long the eggs of this species or the Platte River caddisfly could survive without water, but this adaptation could provide the Platte River caddisfly protection in years with shorter hydroperiods, if it does exhibit this behavior. A shorter hydroperiod would likely be more detrimental in the spring if a slough dried too early as it could prompt the caddisfly to emigrate earlier from the aquatic environment, possibly reducing the size of the larvaand overall fitness of the individual (Harner 2011, pers. comm.).

Recent modeling efforts demonstrated the potential effects of shorter periods of slough inundation on the Platte River caddisfly. Using long-term well data, Harner and Whited (2011, entire) created a model that demonstrated that during a dry period in the record (2000-2003), the type locality slough held water for approximately 249 days, whereas during a wet period (1997-1999), the slough was wet for approximately 340 days (Harner and Whited 2011, p. 21). Most of this drying occurred in summer and fall, and adults were observed in 2003. Larvae were also present at the type locality in the spring of 2004; however, the slough dried more than 2 months earlier in 2004 than what had been observed in years prior, and adults were not observed in the autumn of 2004 (Goldowitz 2004, p. 9). Therefore, droughts that result in sloughs drying too early would likely be more detrimental to the caddisfly than prolonged drying into the autumn and could lead to localized extirpations.

Drought has been implicated in at least the temporary loss of two Platte River caddisfly populations, one of them being the formerly robust type locality. Following the drought, the caddisfly is now again present at the type locality (Gelusoet al.2011, p. 1024) and possibly could have migrated downstream to a more permanent portion of the slough during the extended drought of the early 2000s (Vivian 2011, pers. obs.). Also, the type locality and population near Shelton, Nebraska, occur farther away from the main channel of the Platte River; these areas are less likely to withstand droughts than sloughs closer to the main channel, because hydroperiod decreases with increasing distance from the river (Whileset al.1999, p. 533). Throughout the rest of the range of the Platte River caddisfly, historical aerial imagery from 2003-2006, a period of drought, indicates that the remaining 33 sloughs where the caddisfly is known to occur likely held enough water to support the caddisfly (Vivian 2012, pers. obs.). Thus, it appears that the recent drought had localized effects on a few populations but was not an issue across the range of the species.

Hotter and drier summers in the future are likely to result in increases in evapotranspiration, which may also lead to drier soil conditions (Sorensonet al.1998, p. 344; Johnsonet al.2010, p. 134), and these conditions could impact aestivating caddisfly larvae in areas with an open canopy. However, most caddisfly populations occur in sloughs surrounded by a forest canopy, and this shade cover is likely to provide some protection against evaporative losses from soil and reduce the risk of desiccation (Vivian 2009-2010, pers. obs). The distribution and habitat of the Platte River caddisfly likely confer added protection for the species during times of drought and future climatic extremes. For instance, the species is known from the Platte, Loup, and Elkhorn Rivers, and the Loup and Elkhorn Rivers are tied more to groundwater inputs than snowmelt and precipitation. However, the sloughs along all three river systems are tied to groundwater levels to some degree, and groundwater-fed wetlands are thought to be less vulnerable to climate change than those more tied to inputs of precipitation (Winter 2000, p. 308). Because the caddisfly: (1) Presumably survived the Dust Bowl, a period of extreme dryness on the magnitude expected by climate change; (2) exhibits behaviors that enable it to survive extended dry periods; (3) spans a large geographic area that encompasses a range of annual average precipitation; and (4) is present in more than one habitat type across its range, including in areas that maintain water during droughts, we have determined that habitat impacts associated with climate change do not pose a threat to the caddisfly throughout its range.

The frequency and intensity of floods are projected to increase with the onset of climate change (Saunders and Maxwell 2005, p. 1). However, flooding is not likely to pose a significant threat to the Platte River caddisfly and could be of some benefit. Flooding events can scour aquatic organisms downstream in some systems (Feminella and Resh 1990, p. 2083), but the velocity at which Platte River caddisfly larvae are moved downstream is unknown. The caddisfly may not be subject to scouring flows, because it is found in lentic waters.Ironoquia punctatissimasurvives flood events with discharges of 100 cm/s by seeking refuge in tangled grass roots (Williams and Williams 1975, p. 829), and the Platte River caddisfly may exhibit similar behavior. It has also been recognized that the hyporheic zone (saturated subsurface region, area where groundwater and surface water mixing occurs (del Rosario and Resh 2000)) can be important in the recolonization of benthic macroinvertebrates following flood events (Williams and Hynes 1974, p. 234; Williams and Hynes 1976, p. 266; Boultonet al.1998, p. 64), and the Platte River caddisfly has been found within the hyporheic zone in all five instar stages (Whileset al.1999, p. 535; Vivian 2010, pers. obs.). After high water in May to June 2010, which is during the terrestrial stage of the Platte River caddisfly lifecycle, several live individuals were found along the slough banks at two sites immediately after flood waters had receded (Vivian 2010, p. 52). The burial behavior observed in the Platte River caddisfly may protect a certain portion of terrestrial larvae from late spring floods (Gelusoet al.2011, p. 1024).

Even if mortality of larvae were to occur due to scouring, flooding is likely important in the creation of backwater habitats and the subsequent increase in habitat availability to the Platte River caddisfly. Downstream larval drift is considered an important means of dispersal (Neves 1979, p. 58), but only in habitats that are connected by water (Petersenet al.2004, p. 934). Caddisflies found in isolated habitats or pools are more likely to disperse via flight than by downstream larval drift, because these habitats are not connected (Williams 1996, p. 644; Petersenet al.2004, p. 934). Some inhabitants of temporary wetlands may be strong fliers, such as some limnephilids (Svensson 1974, p. 174); however, observations conducted during the adult life stage suggest the Platte River caddisfly is a weak flier (Vivian 2010, p. 39). An increase in habitat availability due to flooding may increase the chances for the species to colonize new populations and link up areas of suitable habitat. Overall, flooding could increase the amount of suitable habitat for the Platte River caddisfly, and this would likely benefit the species. Because of various behaviors exhibited by the Platte River caddisfly that likely enable it to withstand flooding events, we do not consider flooding or the projected increase in flooding to pose a threat to the caddisfly.

As previously mentioned, historical water development in the Platte Basin contributed to a decline in the active floodplain, and opened up former wet bottomlands for crop development (Currieret al.1985, p. 113). Active efforts to drain wetlands to make an area suitable for row crops also historically contributed to wetland habitat loss, and there has been an estimated 73.5 percent loss of meadows within 3.5 miles of the Platte River as a result of channel narrowing and conversion for agriculture (Currieret al.1985, p. 119). As of 1911, approximately 1.5 million acres of grassland had been converted to row crops in the Platte Valley (Currieret al.1985, p. 113). Agriculture, including the production of row crops,is the predominant land use in Nebraska, and in recent years, a rise in ethanol production has led to an increase in grain prices, which in turn has led to an increase in the number of acres of corn planted in Nebraska (Nebraska Corn Board 2011, entire). Currently, the United States produces around 13 billion gallons of ethanol annually, but the Energy Independence and Security Act of 2007 (42 U.S.C. 17001et seq.) mandates that this number increase to 36 billion gallons by 2022. Increases in the world's population also will likely lead to an increase in the demand for grain, and, in Nebraska, increasing grain production is contributing to a decline in grassland habitat.

Concurrent with the increase in the planting of more acres of corn in Nebraska, ongoing wetland modification may result from the conversion of adjacent grasslands to row crops at a limited number of sites. In 2011, we consulted with the NRCS on approximately 70 sodbuster applications received from Nebraska landowners. Sodbuster applications are submitted by individuals who desire to convert highly erodible grassland into crop production. The increase in sodbuster applications demonstrates that grassland habitats are continually vulnerable to the development of row crops.

The Platte River caddisfly was discovered in a large, grassland complex. At the type locality and Wild Rose Slough, the caddisfly uses adjacent grassland habitat in which to aestivate and complete adult emergence. However, most Platte River caddisfly populations occur in forested sloughs adjacent to the main river channel, and these areas are thought to be buffered against conversion into row crops. Sloughs adjacent to the river also appear to be too deep to be suitable for filling and conversion for agriculture, and these sloughs are also protected from fill under the U.S. Army Corps of Engineers (Corps) 404 program (discussed under Factor D). Therefore, there is not likely to be much overlap between the ongoing conversion of grassland into corn and Platte River caddisfly habitat. As a result, we do not consider wetland conversion to constitute a threat to the species.

Several nongovernmental organizations (NGOs) are actively restoring degraded wetlands in the central Platte region (Whiles and Goldowitz 2005, p. 462); however, restored wetlands often do not equal natural wetlands in terms of floral and faunal diversity (Galatowitsch and van der Walk 1996, entire). Differences in wetland hydrology between natural and restored wetlands can affect the outcomes of restoration projects (Galatowitsch and van der Walk 1996, entire; Meyer and Whiles 2008, entire). For instance, in central Nebraska, it has been shown that some aquatic taxa are missing entirely from restored sloughs as compared to natural sloughs (Meyer and Whiles, 2008, entire).

Restored wetlands, although beneficial in providing habitat for some species, may not immediately provide suitable habitat for the Platte River caddisfly. Between 2009 and 2010, 12 restored sloughs were surveyed for the Platte River caddisfly, and only one slough had evidence of caddisfly presence (Vivian 2010, p. 46). One discarded case was found at this site, and it is unknown whether there is an extant population at this location, as no live individuals were found (Vivian 2010, p. 17). When surveyed, restoration work had occurred 4 years prior to the survey (Schroeder 2011, pers. comm.), and it is unknown if the caddisfly was present before the restoration work had occurred. One other restored slough on Crane Trust property was previously found to support the Platte River caddisfly, but the site supported a low number of individuals. This site was near the type locality (Meyer and Whiles 2008, p. 632; Meyer 2009, pers. comm.), which may represent a source population. These observations suggest that restored sloughs may not be immediately suitable to the caddisfly but could become more suitable over time as the restored sloughs become established.

To date, only one restoration project is known to have resulted in adverse impacts to the Platte River caddisfly. At Bader Park near Chapman, Nebraska, a 2007 restoration project within a slough where the caddisfly was known to occur resulted in a decline in larval densities at that site (Harms 2009, pers. comm.). The caddisfly still occurs at that site, but at a density of less than one individual per m2(Vivian 2010, p. 64), possibly because the slough now harbors various fish species that were not present before the restoration activities occurred. Since the Bader Park project, the Service has drafted guidelines to avoid adverse impacts to the caddisfly while conducting restoration work in sloughs where the species occurs. Overall, we think that restoration projects, if conducted with the Platte River caddisfly in mind, could provide benefits to the caddisfly in terms of an increase in the amount of available habitat, particularly in the long term. Thus, we have determined that wetland modification done as a part of restoration work does not pose a threat to the Platte River caddisfly.

It is likely that urbanization of the Platte River valley has impacted the habitat of the Platte River caddisfly in the past. For instance, 14 bridges span the North Platte and Platte Rivers between Chapman, Nebraska, and Lewellen, Nebraska, a distance of about 380 km (240 mi) (Currieret al.1985, p. 56). Bridge construction can result in localized channel narrowing, because sediments get deposited upstream of the bridge site, and scour occurs downstream of the bridge site for at least a half-mile (Simons and Associates 2000, p. 67). Underneath bridges, channel incision may occur, leading to the degradation of adjacent wetlands as incision can lead to drawdowns of alluvial aquifers (Kondolf 1997, p. 542). Bridge choke points (areas immediately upstream and downstream of bridges where the river has narrowed) can also become open to sandpit development following channel narrowing.

Beginning in the 1980s, the Federal Highway Administration (FHWA) implemented new requirements for bridges to prevent the encroachment of bridge embankments into river channels (Murphyet al.2004, p. 52). Therefore, any present and future bridge projects are required to allow for sufficient room for a river to migrate and create and maintain backwater habitats. Ongoing effects to Platte River caddisfly habitat can be expected at bridge choke points, because no new habitat is being created in those areas. Recently, FHWA contacted the Service to coordinate ways to avoid and minimize impacts to slough habitat during a bridge project at Fullerton, Nebraska. No survey for the Platte River caddisfly has been conducted at that site, but coordination with FWHA demonstrates that potential adverse impacts on the caddisfly resulting from current and future bridge projects can be avoided. For bridge projects and other projects that are federally funded or authorized, the Service has the opportunity and does provide comments to addresses any concerns to listed species, candidate species, and species of concern, such as the Platte River caddisfly (see Factor D).

Along Interstate 80, several sandpit lakes were created to extract gravel used for interstate construction in the 1960s (Currieret al.1985, p. 70); these past operations have been linked to wetland losses along the Platte River (Sidleet al.1989, p. 99). Many of these areas now support housing developments adjacentto the river, and these developments further confine the river to its banks through bank armoring, which reduces the ability of the river to create new channels and backwater areas (Schrammet al.2008, p. 238), which are important habitat for the caddisfly. The construction of Interstate 80 has also contributed to a large amount of direct wetland losses north of the Platte River as the interstate runs within 0.25 mile of the river for over 100 miles in Nebraska (Currieret al.1985, p. 122).

Bank stabilization and armoring projects constructed to protect property against erosion can also cause the localized scouring of a river channel and have the potential to lead to the drying of adjacent wetlands. Bank stabilization efforts, particularly under the Corps' nationwide permitting process, are ongoing throughout Nebraska and have the potential to impact occupied sloughs. However, only one of 35 sites with the caddisfly is currently adjacent to a bank stabilization project, and this site is just upstream of a bridge and does not appear to be degrading the quality of the slough (Vivian 2009, pers. obs.). We have no evidence to indicate that bank armoring along the Platte, Loup, and Elkhorn Rivers is occurring at a large enough scale to adversely impact the caddisfly and its habitat. We do not know of any current or future bank stabilization projects that are scheduled to occur near areas where the caddisfly has been found. Most Platte River caddisfly populations are considered to be protected from bank armoring projects, as 21 out of 35 sites with the caddisfly occur on protected lands.

Overall, most impacts from urbanization and infrastructure projects largely occurred in the past and are localized in their effects. Since the Platte River caddisfly was described in 2000, there is no available information that suggests any habitat losses as a result of bridge construction, road, sandpit, or bank armoring development have occurred. We are not aware of planned projects within caddisfly habitat, and therefore we conclude that urbanization and infrastructure are not likely to pose threats to the Platte River caddisfly.

The Platte River caddisfly and its habitat could be adversely impacted by some cattle grazing regimes. Cattle have a strong affinity for riparian areas because of the availability of water, shade, and high-quality forage (Kauffman and Krueger 1984, p. 431). Cattle can impact wetlands through the reduction of vegetation cover along wetland bottoms and shorelines, increased sedimentation and erosion, increased nutrient and organic inputs from urine and manure, increased water temperatures, and degraded water quality, particularly when cattle have unrestricted access to streams (Schulz and Leininger 1990, pp. 297-298; Fleischner 1994, pp. 631-636; Evans and Norris 1997, p. 627; Downeset al.2000, p. 569; Braccia and Voshell 2006a, p. 269; Braccia and Voshell 2006b, p. 2). A reduction in vegetation cover can lead to decreases in the inputs of coarse particulate organic matter on which the Platte River caddisfly feeds (Kauffman and Krueger 1984, p. 43; Braccia and Voshell 2006a, p. 269). Despite potential impacts, we have no evidence that the species is currently being adversely affected by cattle grazing to the point that grazing would contribute to localized extirpations. Cattle grazing occurs at or adjacent to 6 of 35 Platte River caddisfly sites, and there is no evidence of grazing occurring directly in the sloughs (Vivian 2010, pers. obs.). Also, Wild Rose Slough, which is one of the six sites where grazing occurs, supports the largest known caddisfly population.

A study conducted at Wild Rose Slough to investigate the effects of grazing on the Platte River caddisfly found vegetation productivity to be lower in grazed plots than in ungrazed plots 6 months following the removal of cattle from the study site in spring 2010 (Harner and Geluso 2012, p. 391). In September 2010, fewer adult caddisflies were observed in grazed plots than in ungrazed plots, and in 2011, lower densities of aquatic caddisfly larvae were found in grazed plots than in ungrazed plots (Harner and Geluso 2012, pp. 391-392). Meanwhile, a positive relationship between vegetation productivity and larval densities was observed (Harner and Geluso 2012, pp. 391-392).

Results from the cattle grazing study demonstrated that although cattle were not allowed access to the study area in 2011, the effects of grazing on caddisfly larval densities could still be observed up to one year after grazing occurred (Harner and Geluso 2012, p. 392). These data also suggest that reduced vegetation cover contributed to decreased larval densities in intensely grazed areas within the study plots (Harner and Geluso 2012, p. 392). However, because larvae were not eliminated in grazed areas, this study demonstrates that intense grazing may not be detrimental to the caddisfly for short time periods or under a rotational grazing regime (Harner and Geluso 2012, p. 392) and that this species can likely withstand moderate amounts of grazing, particularly at sites where larval densities are relatively high. Continuous grazing in areas where the caddisfly is less abundant could contribute to localized extirpations, and the caddisfly has not been found at sites that show signs of intense grazing (e.g., more than 40 percent of the bank exposed) (Braccia and Voshell 2006a, p. 271; Vivian 2010, p. 52). However, none of the six sites with the Platte River caddisfly where grazing occurs show signs of overgrazing (Vivian 2010, pers. obs.). Therefore, we have determined that grazing is not likely to pose a threat to the caddisfly.

Corn and soybean fields dominate the river valleys of Nebraska, and both represent potential sources of pesticide exposure to the Platte River caddisfly and its habitat. Should insecticides and herbicides enter occupied habitats of the Platte River caddisfly through runoff, they have the potential to directly impact the species through mortality or indirectly through mortality of aquatic vegetation in the aquatic environment (Fleegeret al.2003, entire; Liess and Von Der Ohe 2005, entire). Pesticides also may enter wetlands through groundwater inputs and could affect aquatic organisms (Spaldinget al.2003, p. 92). Surfactants designed to facilitate pesticide and herbicide application have also been shown to have direct and indirect effects on caddisfly larvae (Belangeret al.2000, entire; Fleegeret al.2003, entire, respectively).

There have been no studies to evaluate the potential effects of pesticide exposure on the Platte River caddisfly. Past studies have demonstrated mortality in other species of caddisflies exposed to pesticides (Liess and Schulz 1996, entire) and documented the absence of caddisflies from polluted waters (Ketelaars and Frantzen 1995, entire). Reduced abundances of aquatic insect species considered sensitive to poor water quality have been observed in habitat adjacent to agricultural areas (Liess and Von Der Ohe 2005, entire) that would presumably contain pesticide runoff.

Aside from agricultural runoff, one potential source of herbicides in Platte River caddisfly habitat is chemicals used for the control of exotic vegetation, such asPhragmites.Because of the establishment ofPhragmitesalong the Platte River, efforts have been taken to control the invasive vegetation using herbicide application. In 2009, the aquatic-safe herbicide Habitat® was sprayed in areas withPhragmitesin the main channel of the Platte River (TheNature Conservancy 2011, entire), and it is possible that drift could cause Habitat® to enter sloughs where the caddisfly occurs. Habitat® may result in lower amounts of dissolved oxygen in sloughs as a result of plant decomposition (BASF® 2010, entire). Some spraying forPhragmitesoccurred in 2009, during the early autumn when Platte River caddisfly adults are active (Vivian 2009, pers. obs.). Lower amounts of dissolved oxygen could impact developing caddisfly eggs or reduce the amount of potentially important shade cover in areas where willow (Salixspp.) co-occurs withPhragmites(Vivian 2010, pers. obs.).

Despite potential adverse impacts to the caddisfly, there is no evidence that population declines or extirpations have occurred as a result of pesticide or herbicide exposure. Following the spraying ofPhragmitesin 2009, the Platte River caddisfly was found again at three of three sites where overlap between spraying and habitat occurred. Most Platte River caddisfly populations are also likely protected from pesticide or herbicide exposure by sufficient buffer strips. For instance, two populations located adjacent to or very near cornfields are likely protected from runoff by a tree and grass buffer of at least 40 meters (131 feet), as the larval densities at these two sites are among the highest of known populations. The 21 populations that occur on protected lands are likely protected from most spray activities typically associated with agriculture. Furthermore, the caddisfly lifecycle likely protects it from some pesticide exposure, because larvae have been observed emigrating from the water as early as mid-April before most crops are in the ground, and the majority of pesticides would enter waterways during the typical farming season in Nebraska of May through October.

In addition to existing regulatory mechanisms and provisions (discussed under Factor D, below), 60 percent (21 of 35) of Platte River caddisfly populations occur on nongovernmental organization or State lands that are protected for conservation or managed as wilderness areas. These conservation efforts may afford protection of Platte River caddisfly habitat now and into the future. Such examples include Nebraska's Wildlife Management Areas (WMAs) and land owned and managed by the Headwaters Corporation, the group responsible for implementing and overseeing PRRIP. To date, Headwaters has been involved in several discussions with the Service on ways to avoid adverse impacts to the caddisfly with projects in and near Platte River caddisfly habitat. Currently, three Platte River caddisfly populations occur on Headwaters lands, and these sites are likely to be protected from future development by way of a conservation easement. Two other populations occur along roadsides in areas managed by the Nebraska Department of Roads (NDOR), and the Service works with NDOR to avoid and minimize impacts to wetlands on road projects.

The Crane Trust is another entity whose lands provide protection for the Platte River caddisfly. The Trust manages 10,000 acres of land in the central Platte region that have been set aside for wildlife in perpetuity. Four Platte River caddisfly populations are known to occur on land owned by the Crane Trust, and these sites support the largest Platte River caddisfly larval densities currently known. In addition, two Platte River caddisfly populations occur on land owned by The Nature Conservancy (TNC), and the organization is aware of these populations and has taken measures to avoid adverse impacts to the species at these sites.

In areas not protected for conservation, many agencies and organizations have been kept apprised of the Platte River caddisfly and have been engaged with the Service on ways to avoid and minimize impacts to the species and its habitat. For instance, the Federal Highway Administration has coordinated with the Service on ways to avoid and minimize impacts during a bridge reconstruction project near potentially suitable habitat (where the caddisfly was thought to occur) near Fullerton, Nebraska (Vivian 2010, pers. obs.). Also, PFW has noted they are willing to consider the Platte River caddisfly in their wetland restoration work that occurs on public and private lands (Schroeder 2012, pers. comm.). In 2011, PFW and TNC involved the Service in discussions on how to avoid adverse impacts to the caddisfly during restoration work at a site on TNC property. In 2010, the Service's Nebraska Field Office held a workshop for personnel from various local, State, and Federal agencies and organizations on the Platte River caddisfly, its habitat, and survey methodology. This workshop equipped agencies outside the Service with the knowledge to be able to avoid impacts to the caddisfly and its habitat.

PRRIP is a program that affords the Platte River caddisfly protection now and into the future throughout the most degraded portion of its range. Objectives of PRRIP that may benefit the Platte River caddisfly include: (1) Preventing the need to list more basin-associated (Platte River) species under the Act; (2) offsetting through mitigation any adverse impacts of new water-related activities on Service-targeted flows in the Platte River basin (target flows are comprised of species flows and annual pulse flows, which have been identified as flows needed to maintain survival of four target species and wildlife that use the Platte River, and to maintain present channel width and keep islands unvegetated (USDOI 2006, pp. 3-11, 3-12)); (3) using available resources to manage program lands for the benefit of non-listed species of concern, like the Platte River caddisfly; (4) providing sufficient water in the central Platte River (Lexington, Nebraska to Chapman, Nebraska) for the benefit of PRRIP's target species (whooping crane, Interior least tern, piping plover, pallid sturgeon) through water conservation projects; and (5) protecting and restoring 29,000 acres of habitat in the central Platte River for the benefit of the four target species (USDOI 2006, pp., 1-3, 1-17). This agreement was put in place to specifically benefit other endangered and threatened species, but should help maintain the backwaters where the Platte River caddisfly occurs, particularly through PRRIP's goal of maintaining current flows in the central Platte River.

Overall, existing programs and organizations that manage land for conservation provide adequate protection for the species and its habitat. Proactive planning efforts with Federal, State, and local agencies, as well as nongovernmental organizations, also help to avoid and minimize impacts to the caddisfly.

Changes in hydrology resulting from water development and its associated effects, including channel degradation and narrowing, invasive species encroachment, urbanization, cropland conversion, groundwater withdrawal, cattle grazing, climate change, pesticides, and floods and droughts, all occur or are likely to occur within the range of the Platte River caddisfly. These environmental stressors will likely continue in the future on each of the river systems where the Platte River caddisfly is known to occur. However, while these stressors are ongoing, when considered individually and collectively, we have determined that they do not pose a threat to the Platte River caddisfly.

The Platte River caddisfly has life-history traits that enable it to survive in an extreme environment, such as theGreat Plains, where climatic extremes are common. These traits are common among species that inhabit temporary (intermittent or ephemeral) wetlands and enable these species to adapt relatively quickly to changing conditions. The Platte River caddisfly can withstand habitat drying, drought, and flooding by burrowing in the soil, aestivating during a time when its habitat is most likely to go dry, inhabiting the hyporheic zone, and possibly laying its eggs in the absence of water (likeIronoquia punctatissima). These life history traits likely render the Platte River caddisfly well-suited to withstand future climatic changes.

We also conclude that the aforementioned stressors do not pose a threat to the species, because the Platte River caddisfly occurs in more than one habitat type and on multiple river systems. Surveys have shown that the caddisfly occupies intermittent and permanent sloughs, forested sloughs, and sloughs with an open canopy. While the type locality and intermittent sloughs most likely represent ideal Platte River caddisfly habitat, the species is found in permanent sloughs, and these may be important during times of drought, as they are likely to hold water longer and serve as a refuge during extended dry periods. Forested canopies may offer an additional source of protection against a warmer and drier climate.

Currently, available information does not indicate whether Platte River caddisfly population levels are increasing or decreasing, or if the amount of potential habitat is increasing or decreasing. Overall, we have documented that the species is more common than previously thought and likely is more abundant now than during the drought in the early 2000s. Also, an increase in surveys is likely to result in an increase in the known range of the caddisfly, given the amount of potential habitat that has yet to be surveyed. Additional survey work would likely result in populations being found on more river systems, such as the Cedar, Niobrara, and Republican Rivers in Nebraska.

Currently, the Platte River caddisfly is known from three river systems, and most of the potential threats occur along the Platte River. Historically, the species likely occupied a much greater portion of the Platte River than today. However, despite all of the water development that has occurred on the Platte River system, the caddisfly still occurs along the majority of the reach surveyed between 2009 and 2011. While ongoing degradation poses a threat to the river and the remaining slough habitat available to the caddisfly, several agencies and nongovernmental entities are working to stem future habitat losses. Therefore, conditions are not anticipated to deteriorate on the Platte River, and we consider the majority of caddisfly populations on the river to be secure.

Currently, the Loup and Elkhorn Rivers have less water development and are less degraded than the Platte River, and the best available information indicates that there is sufficient habitat available (including sloughs not yet surveyed) to sustain the Platte River caddisfly on these systems. Future changes to these river systems are anticipated to occur through increasing sodbusting activities and groundwater withdrawal; however, these activities have little overlap with Platte River caddisfly habitat, and current laws and regulations, such as Nebraska State law LB 962, limit the extent to which this can occur.

After a review of the best available information, we have determined that the present or threatened destruction, modification, or curtailment of its habitat or range does not pose a threat to the Platte River caddisfly.

There is no indication that the Platte River caddisfly is being over collected by hobbyists or researchers, or will be in the future. Collecting of Platte River caddisfly larvae has occurred for scientific purposes (e.g., identification, museum archiving, lab experiments, and genetic analyses), but this has been limited, and largely done at sites supporting the greatest densities of the insect (Alexander and Whiles 2000, p. 1; Vivian 2010, pp. 74-77; Gelusoet al.2011, p. 1022; Cavallaroet al.2011, p. 5). The caddisfly is not known to have been collected for educational purposes.

Insect collectors have not been known to take Platte River caddisfly adults for their collections, likely because caddisfly adults are not as showy as other groups of insects, such as butterflies. Also, caddisfly adults are active during a narrow window (i.e., 3 weeks), and the sites where the species occurs are isolated from urban areas and difficult to access.

There is no evidence that overutilization presents a threat to the Platte River caddisfly. Although small, isolated collections of larvae will likely continue for research purposes, we have determined that these collections do not constitute a threat to the species because, to date, these collections have only been conducted at sites with relatively high larval densities. Therefore, we conclude that the best scientific and commercial information available does not indicate that overutilization for commercial, recreational, scientific, or educational purposes is a threat to the Platte River caddisfly.

Disease and predation play important roles in the natural dynamics of populations and ecosystems. Natural predators of the Platte River caddisfly evolved in conjunction with the caddisfly and do not normally pose a threat to the survival of the species in the absence of other threats. The Platte River caddisfly could be a prey item for predators that are commonly observed in its habitat during its aquatic, terrestrial, and adult stages. Predators of caddisflies in temporary habitats may include large aquatic insects (dragonflies, beetles), amphibians (frogs, salamanders) (Batzer and Wissinger 1996, entire; Wellbornet al.1996, entire), or fish, particularly in more permanent wetlands (Wissingeret al.1999, entire). Aquatic insects, amphibians, and several fish species have all been observed at sites with the Platte River caddisfly, but the sand-grained case of the Platte River caddisfly likely offers it some protection from predators in its environment, as larvae in mineral cases can better withstand crushing than larvae in cases composed of organic material (Otto and Svensson 1980, p. 857).

Despite having mineral cases that can withstand crushing, the brook stickleback (Culaea inconstans) readily consumed Platte River caddisfly larvae in a laboratory setting, typically after the fish removed the larvae from their cases (Cavallaro 2011, pers. comm). The brook stickleback has been found to reduce macroinvertebrate biomass in wetlands in the Western Boreal Forest (Hornung and Foote 2006, entire), and the brook stickleback has been found at five sites with the Platte River caddisfly, but these sites do not support markedly lower densities of the Platte River caddisfly. Also, the caddisfly is well camouflaged in its environment, and field trials have not been conducted to determine if the brook stickleback consumes the Platte River caddisfly in its natural environment. Furthermore, the brook stickleback has been collected upstream and downstream of the central Platte River since 1942, and from the central Platte River since 1987 and possibly earlier (Chadwicket al.1997, p. 285), and the fish is considered native toNebraska (Fischer and Paukert 2008, pp. 372-373). Therefore, the caddisfly and stickleback have likely overlapped in their ranges prior to the discovery of the Platte River caddisfly, and there is no available information to indicate that brook sticklebacks have contributed, or are contributing, to localized extirpations of the caddisfly.

In addition to the brook stickleback, the Platte River caddisfly has been found to occur with other fish predators, including the redear sunfish (Lepomis microlophus), fathead minnow (Pimephales promelas), common carp (Cyprinus carpio), and largemouth bass (Micropterus salmoides) (Vivian 2011, p. 14). However, there is no indication that these fish predators are resulting in population declines at these sites or that these sites support lower densities of the Platte River caddisfly compared to sites without these predators. Therefore, we conclude that predation during the aquatic stage does not pose a threat to the Platte River caddisfly.

The Platte River caddisfly is likely impacted by predation in its terrestrial larval and adult stages. Several caddisfly cases have been recovered that show signs of predation possibly by ants or beetles and small mammals, such as shrews. Signs of predation include tears in the cases or holes at the posterior end of the case (Vivian 2009, pers. obs.). However, the sand-grained larval case likely offers some protection to terrestrial larvae through camouflage and defense against crushing (Otto and Svensson 1980, p. 857). Adults are likely eaten by migratory birds and waterfowl (Whileset al.1999, p. 543). At sites with relatively low numbers of caddisflies, predation on larvae in the terrestrial stage and adults could pose a threat to this species in the future. However, there is no available evidence that the predation of terrestrial larvae or adults is impacting populations of the Platte River caddisfly. Therefore, we do not consider predation during the terrestrial larval and adult life stages to constitute a threat to the species.

Given the small number of individuals at some sites, it is possible that disease could pose a threat to the Platte River caddisfly. However, we have no evidence to suggest that any disease is currently affecting the Platte River caddisfly.

Although the Platte River caddisfly is likely a prey item for various predators (native and non-native), there is no evidence that suggests current levels of predation or disease on the Platte River caddisfly are currently affecting populations or will in the future. Therefore, we conclude that the best scientific and commercial information available indicates that neither disease nor predation poses a threat to the Platte River caddisfly.

Existing Federal, State, and local laws; regulations; and policies that may provide a moderate level of protection for the Platte River caddisfly and its habitat include: The National Environmental Policy Act (NEPA; 42 U.S.C. 4321et seq.), the Fish and Wildlife Coordination Act (FWCA; 16 U.S.C. 661et seq.), section 404 of the Clean Water Act (CWA; 33 U.S.C. 1251et seq.), and Nebraska State law LB 962.

For all federally funded or authorized projects, Federal actions, or projects occurring on Federal lands, an Environmental Assessment or Environmental Impact Statement is required under NEPA. NEPA is a procedural statute that requires federal agencies to consider the environmental impacts of a proposed project and reasonable alternatives to project actions. It also requires full disclosure of all direct, indirect, and cumulative environmental impacts of the project. However, NEPA does not require protection of a particular species or its habitat, nor does it require the selection of a particular course of action. Therefore, NEPA may only provide a limited amount of protection to the caddisfly in situations where NEPA was applicable.

NEPA does not apply to non-Federal projects on private lands or privately funded projects, and about 34 percent (12 of 35 sites) of the known populations of the Platte River caddisfly occur on private lands or near road ditches. Projects occurring on public hunting grounds or access areas, land under the management of conservation groups, and roadsides often receive Federal dollars, and, therefore, NEPA would apply to 66 percent of sites with the Platte River caddisfly. However, as stated above, NEPA does not provide protection to species. There is no available information regarding any development projects, private or otherwise, occurring within Platte River caddisfly habitat. Overall, we conclude that NEPA would provide some protection to the Platte River caddisfly in the event that development projects and slough habitat overlap in the future.

FWCA requires that proponents of Federal water development projects, including those involving stream diversion, channel deepening, impoundment construction, and/or general modifications to water bodies, consider their impacts to fish and wildlife resources. FWCA also requires that impacts to water bodies be offset through mitigation measures developed in coordination with the Service and the appropriate State wildlife agency. FWCA would provide adequate protection to the Platte River caddisfly in the event that water development projects and Platte River caddisfly habitat overlap. However, there is currently no information regarding any current or planned water development projects within the range of the Platte River caddisfly. Should future water development projects occur within Platte River caddisfly habitat, we have determined that FWCA would adequately protect the caddisfly and its habitat, because the Service would be provided an opportunity to address potential concerns with fish and wildlife resources, including the caddisfly.

The U.S. Army Corps of Engineers (Corps), acting under the authority of section 404 of the CWA, regulates the placement of fill materials into waters under Federal jurisdiction, including the filling of wetlands. Historically, according to a 1977 Corps definition, waters under Federal jurisdiction applied to “waters of the United States,” and included intermittent streams, wetlands, sloughs, prairie potholes, and wet meadows. This definition provided protection to nearly all wetlands in the United States (Petrieet al.2001, p. 1). However, two Supreme Court rulings in 2001 and 2006 limited Federal authority under the CWA to regulate certain isolated wetlands (Solid Waste Agency of Northern Cook Countyv.U.S. Army Corps of Engineers,531 U.S. 159, (SWANCC) (2001) andRapanosv.United States,547 U.S. 715 (2006)). Following theSWANCCandRapanosdecisions, it was unknown how the Corps would interpret its jurisdictional lines (Petrieet al.2001, p. 3). According to 2008 guidance documents of the Corps and Environmental Protection Agency, the CWA applies to wetlands adjacent to navigable waters of the United States. This means wetlands must have an unbroken surface or shallow sub-surface connection to jurisdictional waters (even if the connection is intermittent), be physically separated from jurisdictional waters by manmade dikes or barriers or natural river berms, or be in close proximity to navigable waters, supporting the science-based inference that such wetlands have an ecological interconnection with jurisdictional waters.

Currently, most Corps permit applications in central Nebraska are forrestoration work along the Platte River by groups such as the PFW, NGPC, and Ducks Unlimited (Moeschen 2011, pers. comm.). Typically, the Service is made aware of these projects and has educated restoration proponents on the Platte River caddisfly and its habitat so as to avoid potential adverse impacts to extant populations. Also, sand and gravel mining operations, if occurring within wetlands along the river, would require a Corps permit. A Corps permit would provide the Service with adequate opportunity to address concerns regarding fish and wildlife resources, and any issued permit would require mitigation (offset impacts, restore area of equal habitat value) at a minimum ratio of 1:1 (Corps 2005, p. 18). Furthermore, the Corps has been kept apprised of all sites where the caddisfly occurs, and two Corps representatives attended a workshop in 2010 that educated various agency personnel on the Platte River caddisfly and its habitat.

Most sloughs that support a Platte River caddisfly population occur in areas directly connected to or adjacent to the main channel of the Platte, Loup, and Elkhorn Rivers. Adjacency under CWA is easily determined for these sloughs. Four of the 35 sites occur in more off-channel areas, and adjacency for these sloughs may not be as easily determined. Despite occurring in more off-channel areas, these four sloughs still likely receive protection from fill. For instance, two sites on the Elkhorn River occur along roadsides, and FHWA and the Nebraska Department of Roads notifies the Service when work within or near wetland areas is scheduled to occur. If these areas become subject to fill activities in the future, the Service would have an opportunity to recommend ways to avoid and minimize impacts to the wetlands. Meanwhile, Wild Rose Slough and the type locality on Crane Trust property are protected from fill activities by way of a conservation easement. Overall, 23 of 35 caddisfly populations occur within WMAs or lands managed for conservation or roadsides and are protected from most fill and development activities in wetlands (with the exception of restoration work). Thus, the CWA adequately protects the Platte River caddisfly and its habitat from fill and development activities now and into the future, because: (1) The CWA would apply to the majority of populations should such activities occur in the future; (2) 66 percent of populations occur in protected areas; and (3) the Service and Corps have engaged in proactive planning efforts so as to avoid impact to the caddisfly and its habitat.

Several governmental and nongovernmental agencies are working to secure water rights for environmental benefits and endangered and threatened species in Nebraska; however, instream flow appropriations do not ensure a stream will always contain water (Czaplewski 2009, entire). Instream appropriations only ensure that the minimum flow needs of species will be met before any future water development projects can occur (Czaplewski 2009, entire). Therefore, in times of drought and low flows, pre-existing water rights will be met before the minimum flow needs of fish and wildlife species are met. However, we previously determined that the Platte River caddisfly can withstand drought to a certain degree even when coupled with existing water development projects.

The Central Platte Natural Resources District (CPNRD) and NGPC each have protected instream flow rights along the Platte River; however, these are not enough to cover “target flows” outlined by the PRRIP (NGPC 2008, p. 7). The PRRIP is working to address shortages to target flows by managing an environmental account from reservoirs along the Platte River in Nebraska and leasing water rights from willing landowners. The PRRIP also has a goal of offsetting new depletions to the system that occurred after July 1997 and restoring flows to the river by 130,000 to 150,000 acre-feet per year between 2007 and 2019. Efforts to augment current Platte River flows should provide adequate protection for the Platte River caddisfly populations along the Platte River, possibly with the exception of the type locality and Wild Rose Slough. For instance, as discussed under Factor A, even with more water in the river channel, the type locality and Wild Rose Slough may not become inundated or remain inundated long enough to meet the needs of the Platte River caddisfly (Harner and Whited 2011, entire). Furthermore, the PRRIP seeks to augment sediment inputs to the central Platte River, which should also help prevent future channel degradation from impacting sloughs where the caddisfly occurs.

Passed in 2004, Nebraska State law LB 962 requires the Nebraska Department of Natural Resources to work with each of the 23 Nebraska Natural Resource Districts (NRDs) to address surface water and groundwater appropriations in fully or over-appropriated basins. Basins designated as fully appropriated are required to place a moratorium on any new groundwater wells until an integrated management plan to address depletion issues can be developed (NGPC 2008, p. 18). The law does not prevent new groundwater wells from being drilled outside fully appropriated basins, such as some areas on the Loup River. Future groundwater well construction could contribute to some future loss in slough habitat on the Loup and Elkhorn Rivers as has been observed on the Platte, leading to future caddisfly habitat loss. However, we estimate that the amount of habitat that could be impacted is small, because new development is done on a limited basis, and each NRD monitors groundwater and stream levels annually to ensure water resources are not being depleted.

Given that 66 percent of Platte River caddisfly populations occur on protected lands, and current laws and regulations provide adequate protection for slough habitat on private lands should future activities occur within slough habitat, we conclude that the inadequacy of existing regulatory mechanisms does not pose a threat to the Platte River caddisfly.

Small insect populations may be vulnerable to extirpation as a result of random genetic drift, naturally occurring stochastic events, or demographic stochasticity (Pimmet al.1988, p. 757; Boyce 1992, p. 482; Purviset al.2000, p. 1949; Melbourne and Hastings 2008, p. 3). Extinction of small populations is also likely to happen more quickly than extinction of larger populations due to inbreeding (Brooket al.2002, pp. 3-4), and this could affect the Platte River caddisfly in the future.

We do not know the true population size of any of the known Platte River caddisfly populations, but we do have information on the numbers of individuals at 18 sites with the caddisfly. We previously discussed that some sites support relatively low densities of the Platte River caddisfly, but determined that finding low numbers of individuals at a site is typical of theIronoquiagenus. We also determined that varying population levels across the range of the Platte River caddisfly likely represent the norm for the species, and varying population densities are likely a product of the species occurring in more than one type of habitat. Also, because of various life history traits that enable thecaddisfly to survive in temporary habitats, the caddisfly is more able to withstand stochastic events than species less tolerant of extreme weather events. Therefore, we have determined that small population size does not pose a threat to the caddisfly.

The adult stage likely represents the most probable means of dispersal (Williams 1996, p. 644; Petersenet al.2004, p. 934) for the Platte River caddisfly. Poor adult flight capabilities and a short window of adult activity indicate that Platte River caddisfly dispersal to new habitats and between populations is likely a rare event. Observations when adults are active have found individuals underneath vegetation and on or near the ground, particularly when it is windy, and above vegetation or immediately adjacent to standing water in slough habitat during more favorable weather conditions (Vivian 2009, pers. obs.; Vivian 2010, pers. obs.; Gelusoet al.2011, p. 1024). When active, the caddisfly has only once been observed to fly more than 10 meters, and wind seemed to greatly influence that individual (Vivian 2009, pers. obs.; Vivian 2010, pers. obs.). Platte River caddisfly adults are also active for a short period of time (i.e., about 2 to 3 weeks) (Whileset al.1999, p. 539; Goldowitz 2004, p. 6), and this likely limits the species' dispersal ability compared to other caddisflies with longer adult lifespans (Svensson 1972; entire) and could reduce the amount of genetic variability within populations.

Genetics techniques can be used to assess a species' dispersal ability in the absence of direct observations of significant dispersal events (Kellyet al.2002, p. 1642). Amplified Fragment Length Polymorphism has been used to determine the amount of genetic similarity among five caddisfly populations from the Platte, Loup, and Elkhorn Rivers (Cavallaroet al.2011, entire). It was found that one Platte River caddisfly population from near Sutherland, Nebraska, and one near Kearney, Nebraska, had more genetic similarity to each other than the population near Kearney did to a population near Gibbon, Nebraska, despite the closer proximity of Kearney and Gibbon. Also, the population near Gibbon was found to be more closely related to the population near Loup City, Nebraska, even though Loup City is farther from Gibbon than Kearney (∼21 km or 13.1 mi) (Bunn and Hughes 1997, p. 341; Cavallaroet al.2011, pp. 12, 15). The Elkhorn River population tested was found to be the most dissimilar from all other populations (Cavallaroet al.2011, p. 7), but this may be more a product of geographic isolation as opposed to habitat fragmentation. It was also established that there is a low amount of gene flow among existing Platte River caddisfly populations and more intra-population variation than inter-population variation (Cavallaroet al.2011, pp. 6-7).

The amount of genetic variability observed in the Platte River caddisfly (Cavallaroet al.2011, p. 7) is similar to what has been observed in the caddisflyWormaldia tagananana,which is identified as having a limited range and presumed limited dispersal ability (Kellyet al.2002, p. 1646). Low gene flow between Platte River caddisfly populations further corroborates that the caddisfly has a limited ability to disperse to new habitats (e.g., restored sloughs, sites that were previously extirpated), and that successful dispersal to new habitats likely depends upon just a few individuals (Schmidtet al.1995, p. 154; Cavallaroet al.2011, pp. 6-7).

Although it has been identified that the Platte River caddisfly is a poor disperser, this is a natural life-history trait. This behavior would be detrimental to the species if the existing populations remained isolated from one another. However, we have not identified that habitat loss is presently occurring to the extent that the fragmentation of Platte River caddisfly populations poses a threat to the species. While sloughs on the different river systems and on both sides of the 155-km (93-mi) distribution gap between Hershey and Elm Creek, Nebraska, are isolated from one another, there is evidence of gamete (male and female reproductive cells) exchange across river systems given the similarity between the sites near Gibbon and Loup City and between Kearney and Sutherland. Furthermore, there have been live individuals or cases found at two restored sites. These observations indicate that there is a limited amount of dispersal occurring within relatively short time periods across short distances.

In summary, although small population size and limited dispersal ability have the potential to adversely impact the Platte River caddisfly, there is no evidence that this is occurring or is likely to occur in the near future. For instance, there are no known caddisfly population extirpations that have occurred as a result of small population size. We previously established that the Platte River caddisfly has the ability to recolonize sloughs following stochastic events and is well adapted to the environmental extremes found in the Great Plains. Therefore, we conclude that other natural or manmade factors do not pose a threat to the species.

Some of the threats discussed in this finding can work in concert with one another to cumulatively create situations that will impact the Platte River caddisfly beyond the scope of each individual threat. For example, as mentioned under Factor A, the impacts of water development on Platte River caddisfly habitat could be exacerbated by the effects of drought and the projected increases in drought resulting from climate change. In the absence of water development projects across the landscape, the Platte River caddisfly is naturally tolerant of drought because of its semi-terrestrial lifecycle and ability to recolonize sloughs once they become inundated again following extended dry periods. However, in the presence of water development, projects that remove water from the Platte, Loup, and Elkhorn Rivers have the potential to reduce the amount of available habitat across the landscape to the point that, during drought, enough refugia may not be available to sustain existing populations. Also, because of climate change, the frequency of droughts is expected to increase, and this will likely be exacerbated by ongoing water development. Water development has the ability to exacerbate the effects of drought (climate change-related or otherwise), because less water is flowing through the system than what there would be in the absence of water development. Future, extreme droughts and climate change are also expected to facilitate the spread of non-native vegetation, and this could result in a loss in habitat due to the encroachment of exotic vegetation in sloughs. Because of these relationships, we will analyze the cumulative impact of drought (as a result of climate change), water development (human-caused water reduction), and invasive species.

As mentioned previously, under normal conditions and otherwise, the Platte River caddisfly has the ability to withstand drought, because it enters into a dormant phase during the typical summer dry period. However, extreme drought can adversely impact the caddisfly to the point that it results in localized extirpations. For instance, extreme drought resulted in the extirpation of the type locality and onesite near Shelton, Nebraska, in the early 2000s. The species has since recolonized the type locality. The Shelton site has not been surveyed since 2009, but it is possible the Platte River caddisfly has recolonized this area. This indicates that there was likely sufficient habitat available near the type locality during the drought to serve as refugia for the caddisfly, and that within a short period of time following disturbance, the species founded new populations in previously occupied habitat.

The drought in the early 2000s occurred during a time when water development projects, such as dams and diversions, were prevalent across the landscape, particularly along the Platte River. The Platte River is considered to be the most degraded portion of the range of the caddisfly, but no new, large water projects have been implemented since 1956. Under current laws and regulations, we anticipate that current conditions with respect to water development are not anticipated to deteriorate along the Platte River or appreciably diminish on the Loup and Elkhorn Rivers.

The caddisfly has already been shown to withstand the combined effects of extreme drought and water-related impacts to its habitat. The species is also still present following the proliferation of invasive species along the Platte River during the drought in the early 2000s. Meanwhile, there are no new, large-scale water development projects planned within the range of the caddisfly. Therefore, the amount of habitat available to the caddisfly is not anticipated to greatly diminish because of water development now or into the future. While future, extreme droughts could result in extirpations of the caddisfly at a local scale, from examining satellite imagery to identify slough habitat, we find there is sufficient habitat available surrounding current populations to serve as refugia for the species during drought. Thus, there is no information to suggest that future, extreme droughts resulting from climate change and current water development projects will reduce the ability of existing caddisfly populations to sustain themselves under a warmer and drier climate.

We previously identified that at three Platte River caddisfly sites along the Platte River,Phalaris arundinacea(reed canarygrass) may encroach enough in the future to contribute to the extirpation of the caddisfly at these locations. There is no evidence that suggestsPhalaris arundinaceais resulting in habitat loss at the remaining 32 sites where the species occurs. Because of the current small number of sites affected by invasive species (3 of 35), and our inability to predict the future effects of invasive species on other caddisfly sites, we do not find that invasive species pose a threat to the species now or in the future.

As required by the Act, we considered the five factors in assessing whether the Platte River caddisfly is endangered or threatened throughout all of its range. We examined the best scientific and commercial information available regarding the past, present, and future threats faced by the Platte River caddisfly. We reviewed the petition, information available in our files, other available published and unpublished information, and we consulted with recognized caddisfly, slough, and hydrology experts and other Federal, State, and nongovernmental entities. On the basis of the best scientific and commercial information available, we find that the Platte River caddisfly is not in danger of extinction (endangered species) now or likely to become an endangered species within the foreseeable future (threatened species), throughout all or a significant portion of its range. Therefore, we find that listing the Platte River caddisfly as an endangered or threatened species is not warranted throughout its range at this time.

The Platte River caddisfly is currently known from 35 locations across three river systems, and the number of populations would most likely increase with additional survey efforts, because potentially suitable habitat has been identified but has not been surveyed. Meanwhile, with the exception of the type locality, there is a lack of information on population trends. It appears that the caddisfly naturally occurs at varying densities depending on habitat type and may even be classified as a habitat generalist. Because the species occurs in more than one habitat type on three different river systems, the caddisfly is well-represented across the landscape and is resilient to the various stressors present throughout its range.

In this finding, we identified a number of potential stressors under Factor A. The stressor most likely to constitute a threat to the Platte River caddisfly and its habitat in the future is landscape-level changes in hydrology. The Platte River is one of the most managed river systems in the United States and contains several impoundments, diversions, and groundwater withdrawals that have resulted in hydrological and morphological changes to the floodplain. The dewatering of the Platte River likely resulted in historical losses of Platte River caddisfly habitat. Nonetheless, we have established that most remaining populations are likely to remain adequately protected across this portion of the species' range because of programs, such as PRRIP and PFW, and the existence of protected areas where many Platte River caddisfly populations occur. Although ongoing and future Platte River channel degradation could potentially affect the Platte River caddisfly and its habitat in the future, particularly at the Crane Trust, restoration efforts are ongoing along the central Platte River to stem this trend. These efforts should protect caddisfly populations along the Platte River, where most stressors are concentrated, now and into the future.

Climate change is a concern and is likely to render the range of the Platte River caddisfly hotter and drier. Nonetheless, we have determined that the species should withstand future climatic changes because of various life-history traits that are common among semi-terrestrial caddisflies and because of the distribution of its habitat across the landscape. We have determined that the present or threatened destruction, modification, or curtailment of its habitat or range (Factor A) is not a threat to the Platte River caddisfly at this time.

We have determined that overutilization for commercial, recreational, or scientific use (Factor B) is not a threat to the species at this time. Neither disease nor predation (Factor C) is known or expected to be a threat to the species. We have determined that the inadequacy of existing regulatory mechanisms (Factor D) is not a threat to the Platte River caddisfly, and that regulatory mechanisms currently in place provide protection to the species. Regarding other natural or manmade factors affecting its continued existence (Factor E), we do not consider small population size or limited dispersal ability to constitute a threat to the species. The available information does not indicate that the caddisfly is being impacted genetically, or in any other way, as a result of small population size or limited dispersal ability, or that it will become an endangered or threatened species in the foreseeable future due to stochastic events. We have also examined the cumulative impact of various stressors acting together and whether those pose a threat to the caddisfly. We have determined that, when examined together, the cumulative impact of various stressors does not pose a threat to the caddisfly.

Having determined that the Platte River caddisfly is not an endangered or threatened species throughout its range, we must next consider whether there are any significant portions of its range where the species is in danger of extinction or is likely to become an endangered species in the foreseeable future. The Act defines “endangered species” as any species which is “in danger of extinction throughout all or a significant portion of its range,” and “threatened species” as any species which is “likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” The phrase “significant portion of its range” (SPR) is not defined by the statute, and we have no regulation governing SPR.

We interpret the phrase “significant portion of its range” in the Act's definitions of “endangered species” and “threatened species” to provide an independent basis for listing; thus, there are two situations (or factual bases) under which a species would qualify for listing: A species may be an endangered or threatened species throughout all of its range; or a species may be an endangered or threatened species in only a significant portion of its range. If a species is in danger of extinction throughout an SPR, the species is an “endangered species.” The same analysis applies to “threatened species.” Based on this interpretation and supported by existing case law, the consequence of finding that a species is an endangered or threatened species in only a significant portion of its range is that the entire species will be listed as an endangered or threatened species, respectively, and the Act's protections will be applied across the species' entire range. Because “significant portion of its range” provides an independent basis for listing and protecting the entire species, we next turn to the meaning of “significant” to determine the threshold for when such an independent basis for listing exists.

Although there are potentially many ways to determine whether a portion of a species' range is “significant,” the significance of the portion of the range should be determined based on its biological contribution to the conservation of the species. For this reason, we describe the threshold for “significant” in terms of an increase in the risk of extinction for the species. We conclude that a biologically based definition of “significant” best conforms to the purposes of the Act, is consistent with judicial interpretations, and best ensures species' conservation. Thus, as explained further below, a portion of the range of a species is “significant” if its contribution to the viability of the species is so important that without that portion, the species would be in danger of extinction.

We evaluate biological significance based on the principles of conservation biology using the concepts of redundancy, resiliency, and representation.Resiliencydescribes the characteristics of a species and its habitat that allow it to recover from periodic disturbance.Redundancy(having multiple populations distributed across the landscape) may be needed to provide a margin of safety for the species to withstand catastrophic events.Representation(the range of variation found in a species) ensures that the species' adaptive capabilities are conserved. Redundancy, resiliency, and representation are not independent of each other, and some characteristic of a species or area may contribute to all three. For example, distribution across a wide variety of habitat types is an indicator of representation, but it may also may indicate a broad geographic distribution contributing to redundancy (decreasing the chance that any one event affects the entire species), and the likelihood that some habitat types are less susceptible to certain threats, contributing to resiliency (the ability of the species to recover from disturbance). None of these concepts is intended to be mutually exclusive, and a portion of a species' range may be determined to be “significant” due to its contributions under any one or more of these concepts.

We determine if a portion's biological contribution is so important that the portion qualifies as “significant” by asking whetherwithout that portion,the representation, redundancy, or resiliency of the species would be so impaired that the species would have an increased vulnerability to threats to the point that the overall species would be in danger of extinction (i.e., would be “an endangered species”). Conversely, we would not consider the portion of the range at issue to be “significant” if there is sufficient resiliency, redundancy, and representation elsewhere in the species' range that the species would not be in danger of extinction throughout its range if the population in that portion of the range in question became extirpated (extinct locally).

We recognize that this definition of “significant” (a portion of the range of a species is “significant” if its contribution to the viability of the species is so important that without that portion, the species would be in danger of extinction) establishes a threshold that is relatively high. On the one hand, given that the consequences of finding a species to be an endangered or threatened species in an SPR would be listing the species throughout its entire range, it is important to use a threshold for “significant” that is robust. It would not be meaningful or appropriate to establish a very low threshold whereby a portion of the range can be considered “significant” even if only a negligible increase in extinction risk would result from its loss. Because nearly any portion of a species' range can be said to contribute some increment to a species' viability, use of such a low threshold would require us to impose restrictions and expend conservation resources disproportionately to achieve conservation benefits. This would result in the listing being rangewide, even if only a portion of the range of minor conservation importance to the species is imperiled. On the other hand, it would be inappropriate to establish a threshold for “significant” that is too high. This would be the case if the standard were, for example, that a portion of the range can be considered “significant” only if threats in that portion result in the entire species' being currently endangered or threatened. Such a high bar would not give the SPR phrase independent meaning, as the Ninth Circuit held inDefenders of Wildlifev.Norton,258 F.3d 1136 (9th Cir. 2001).

The definition of “significant” used in this finding carefully balances these concerns. By setting a relatively high threshold, we minimize the degree to which restrictions will be imposed or resources expended that do not contribute substantially to species conservation. But we have not set the threshold so high that the phrase “in a significant portion of its range” loses independent meaning. Specifically, we have not set the threshold as high as it was under the interpretation presented by the Service in theDefenderslitigation. Under that interpretation, the portion of the range would have to be so important that current imperilment there would mean that the species would becurrentlyimperiled everywhere. Under the definition of “significant,” the portion of the range need not rise to such an exceptionally high level of biological significance. (We recognize that if the species is imperiled in a portion that rises to that level of biological significance, then we should conclude that the species is in fact imperiled throughout all of its range, and that we would not need to rely on the SPR language for such a listing.)Rather, under this interpretation we ask whether the species would be an endangered species everywhere without that portion, i.e., if that portion were completely extirpated. In other words, the portion of the range need not be so important that even the species being in danger of extinction in that portion would be sufficient to cause the species in the remainder of the range to be an endangered species; rather, thecomplete extirpation(in a hypothetical future) of the species in that portion would be required to cause the species in the remainder of the range to be an endangered species.

The range of a species can theoretically be divided into portions in an infinite number of ways. However, there is no purpose to analyzing portions of the range that have no reasonable potential to be significant or to analyzing portions of the range in which there is no reasonable potential for the species to be an endangered or threatened species. To identify only those portions that warrant further consideration, we determine whether there is substantial information indicating that: (1) The portions may be “significant,”and(2) the species may be in danger of extinction there or likely to become so within the foreseeable future. Depending on the biology of the species, its range, and the threats it faces, it might be more efficient for us to address the significance question first or the status question first. Thus, if we determine that a portion of the range is not “significant,” we do not need to determine whether the species is an endangered or threatened species there; if we determine that the species is not endangered or threatened in a portion of its range, we do not need to determine if that portion is “significant.” In practice, a key part of the determination that a species is in danger of extinction in a significant portion of its range is whether the threats are geographically concentrated in some way. If the threats to the species are essentially uniform throughout its range, no portion is likely to warrant further consideration. Moreover, if any concentration of threats to the species occurs only in portions of the species' range that clearly would not meet the biologically based definition of “significant,” such portions will not warrant further consideration.

To determine whether the Platte River caddisfly could be considered an endangered or threatened species in a “significant portion of its range”, we reviewed the best scientific information with respect to the geographic concentration of threats and the significance of portions of the range to the conservation of the species. We first evaluated whether substantial information indicated (i) the threats are so concentrated in any portion of the species' range that the species may be currently in danger of extinction in that portion; and (ii) if so, whether those portions may be significant to the conservation of the species. Our rangewide review of the species concluded that the Platte River caddisfly is not an endangered or threatened species. As described above, to establish whether any areas may warrant further consideration, we reviewed our analysis of the five listing factors to determine whether any of the potential threats identified were so concentrated among the 35 populations that some portion of the range of the Platte River caddisfly may be in danger of extinction now or in the foreseeable future.

We found that most potential threats evaluated in this rule were concentrated on the Platte River, and we have determined that these potential threats, including but not limited to: landscape level changes in hydrology, invasive species, climate change, drought, flooding, grazing, inadequacy of existing regulatory mechanisms, and poor dispersal ability, are not resulting in current losses of slough habitat or losses of any of the 28 populations of the Platte River caddisfly along the Platte River, nor are they likely to do so in the foreseeable future. In addition, we find that the Platte River portion of the range of the caddisfly is not endangered or threatened because of existing programs and entities that are striving to protect current channel conditions. There is also no information to indicate that the potential threats analyzed under the five factors are contributing to a decline in the number of Platte River caddisfly populations or amount of slough habitat available along the central Platte River. For instance, we analyzed projected increases in the frequency of droughts in central Nebraska and how this could impact the Platte River caddisfly and its habitat. We also considered how the effects of climate change may be compounded by current levels of water development and have determined that these threats are not likely to pose a threat to the Platte River caddisfly across its range. Therefore, based on our review, the available information does not indicate that any of the potential threats we evaluated in all the factors under the Act were so concentrated in any portion of the species' range as to find that the Platte River caddisfly may currently be in danger of extinction in that portion of its range. Because we find that the Platte River caddisfly is not an endangered species in any portion of its range now or in the foreseeable future, we need not address the question of whether any portion may be significant.

Our review of the information pertaining to the five factors does not support the assertion that there are threats acting on the species or its habitat that have rendered the Platte River caddisfly to be in danger of extinction or likely to become so in the foreseeable future, throughout all or a significant portion of its range. Therefore, listing the Platte River caddisfly as an endangered or threatened species under the Act is not warranted at this time.

We request that you submit any new information concerning the status of, or threats to, the Platte River caddisfly to our Nebraska Field Office (seeADDRESSES) whenever it becomes available. New information will help us monitor the Platte River caddisfly and encourage its conservation. If an emergency situation develops for the Platte River caddisfly or any other species, we will act to provide immediate protection.

A complete list of references cited is available on the Internet athttp://www.regulations.govand upon request from the Nebraska Field Office (seeADDRESSES).

The primary authors of this notice are the staff members of the Nebraska Field Office.

The authority for this action is section 4 of the Endangered Species Act of 1973, as amended (16 U.S.C. 1531et seq.).

A description of the legal authority, history of the Steller sea lion protection measures, litigation, potential alternatives, and issues for analysis are in theFederal Registernotice of intent for the preparation of the EIS (77 FR 22750, April 17, 2012). Detailed descriptions of the current Steller sea lion protection measures and the development of the EIS are available from the NMFS Alaska Region Web page athttp://www.alaskafisheries.noaa.gov/sustainablefisheries/sslpm/.

NMFS is seeking written public comments on the scope of issues that should be addressed in the EIS and alternatives that should be considered in revising the Steller sea lion protection measures. NMFS will accept comments in writing at the address above (seeADDRESSES). Written comments should be as specific as possible to be the most helpful.

The public is invited to attend the scoping meeting on Tuesday, October 2, 2012, in Anchorage, AK, which will be held in coordination with the NPFMC meeting. At the scoping meeting, NMFS will present background on the development of the EIS and scoping issues that have been identified. The public will have the opportunity to ask questions of NMFS staff regarding the EIS and may submit written comments at that time (seeADDRESSES).

Please visit the NMFS Alaska Region Web page athttp://www.alaskafisheries.noaa.gov/sustainablefisheries/sslpm/formore information on this EIS, guidance for submitting effective public comments, and to order a draft EIS. NMFS estimates that a draft EIS will be available in May 2013.

These meetings are physically accessible to people with disabilities. Requests for sign language interpretation or other auxiliary aids should be directed to Gail Bendixen, NPFMC, 907-271-2809, at least five days prior to the meeting date.