[Federal Register Volume 63, Number 171 (Thursday, September 3, 1998)]
[Rules and Regulations]
[Pages 46900-46910]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-23729]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AE31


Endangered and Threatened Wildlife and Plants; Final Rule To List 
the Illinois Cave Amphipod as Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: The U.S. Fish and Wildlife Service (Service) determines the 
Illinois cave amphipod (Gammarus acherondytes) to be an endangered 
species pursuant to the Endangered Species Act (Act) of 1973, as 
amended. Historically, the Illinois cave amphipod was known from six 
cave streams in Monroe and St. Clair counties, Illinois. This amphipod 
is a cave-dependent species living in the dark zone of cave entrances. 
Recent surveys have found the species at only three of the original six 
sites, although one of the six sites is no longer accessible for 
surveys. This species is believed to be threatened primarily by 
degraded groundwater quality resulting from various sources, such as 
the application of agricultural and residential pesticides and 
fertilizers in cave stream recharge areas, and contamination from human 
and animal wastes from residential septic systems and livestock 
feedlots. This action implements the Federal protection of the Act for 
the Illinois cave amphipod.


[[Page 46901]]


DATES: This rule is effective October 5, 1998.

ADDRESSES: The complete file for this rule is available for public 
inspection, by appointment, during normal business hours at the U.S. 
Fish and Wildlife Service's Rock Island Field Office, 4469 48th Avenue 
Court, Rock Island, Illinois 61201.

FOR FURTHER INFORMATION CONTACT: Richard C. Nelson, Field Supervisor, 
Illinois Field Office (see ADDRESSES section) (telephone 309/793-5800; 
facsimile 309/793-5804).

SUPPLEMENTARY INFORMATION:

Background

    Hubricht and Mackin (1940) described the Illinois cave amphipod 
(Gammarus acherondytes). Leslie Hubricht collected the Type specimens 
in 1938 from Morrison's Cave (now Illinois Caverns), near Burksville, 
Illinois.
    Sexually mature males are up to 20.0 millimeters (mm) (0.8 inch 
(in.)) long; sexually mature females are 12.0 to 16.0 mm (0.5 to 0.6 
in.) long. The amphipod's color is light gray-blue, and the eyes are 
reniform (kidney-shaped), small and degenerate with the pigment drawn 
away from the facets in an irregular black mass. The first antenna is 
long and slender, more than one-half the length of the body. The 
primary flagellum has up to 40 segments and the secondary flagellum has 
up to 6 segments. The second antenna is about three-fourths as long as 
the first antenna. The flagellum of the second antenna has up to 18 
segments and lacks sensory organs in either sex. Hubricht and Mackin 
(1940) reported that its clutch size is up to 21 eggs, and Holsinger 
(1972) reported that ovigerous (egg-bearing) females have been observed 
in summer and fall.
    This species is best differentiated from other amphipods in the 
field, especially from Gammarus fasciatus, which it resembles, by its 
color, small degenerate eyes, and a much longer first antenna. It is 
usually associated with the larger G. troglophilus (Hubricht and Mackin 
1940) but is much less common (Holsinger 1972).
    This species is a troglobitic (cave-dependent) species inhabiting 
the dark zone of cave streams. As a group, amphipods require cold water 
and are intolerant of wide ranges in temperature. They are strongly 
sensitive to touch and react negatively to light. High levels of 
dissolved oxygen appear to be an environmental necessity. They are 
omnivorous scavengers, feeding on dead animal and plant matter or the 
thin bacterial film covering most submerged surfaces throughout their 
aquatic habitat.
    The Illinois cave amphipod is endemic to the Illinois Sinkhole 
Plain of Monroe and St. Clair counties and was historically known from 
six cave systems, which are all within a 16-kilometer (10-mile) radius 
of Waterloo, Illinois. The main entrances to two of the caves, Illinois 
Caverns and Fogelpole Cave, are in public ownership and the other four 
are privately owned. The cave streams from which this species is 
historically known are each fed by a distinct watershed or recharge 
area; and there are no known interconnections between them, or with 
other cave systems. Two of the six caves may become hydrologically 
connected during extremely high rainfall over short periods of time 
(Samuel V. Panno, Illinois Natural History Survey, Champaign, IL, in 
litt. 1996). Thus, it is believed that there is virtually no 
opportunity for this species to become distributed to other cave 
systems via natural pathways.
    There are few data or adequate survey techniques on which to base 
population, productivity, or trend estimates for this species. Sampling 
for cave fauna is difficult at best, and the challenges of surveying 
are compounded by the relatively small size of this species and the 
difficulty of researchers to distinguish it from other similar 
amphipods in the field. Thus, survey data are not sufficient to 
accurately record numbers of this small subterranean invertebrate; 
however, they do demonstrate a reduction in its range and the number of 
extant populations. Since Hubricht's initial 1938 collections of 
unknown numbers from 2 caves, other collections have been made in 1965 
(at least 19 specimens taken from the 2 caves sampled in 1938, plus a 
third cave), 1972 (unknown numbers taken from 2 additional caves), 1974 
(6 specimens taken from 1 cave sampled in 1938), 1986 (2 specimens 
taken from 1 cave sampled in 1938 and from a new, sixth cave), 1992 (20 
specimens taken from 1 cave sampled in 1938), and 1993 (11 specimens 
taken from 2 caves sampled in 1938) (Webb 1995).
    The most recent and extensive sampling effort was in 1995 in which 
the Illinois Natural History Survey (INHS) investigated 25 caves in the 
Illinois Sinkhole Plain and confirmed the presence of the species in 
only 3 of the original 6 cave systems, all in Monroe County. The 
species was not found in any additional caves (Webb et al. 1993, Webb 
1995). In 1995, 56 specimens were taken from Illinois Caverns, 19 
specimens from Fogelpole Cave, and 2 specimens from a third, privately 
owned cave. The species appears to be extirpated from the two caves 
where no specimens were collected in 1965 or 1986. Its status in a 
sixth cave is currently unknown because the cave entrance has been 
closed by the landowner, thus the cave has not been re-surveyed since 
1965. Due to the extensive searches by INHS, it is possible, but 
unlikely, that there are populations in other caves in the Illinois 
Sinkhole Plain. The INHS made an intensive effort to collect in all 
small side rivulets and drip pools in the 25 caves it sampled and 
believes that the collection results reasonably reflect the relative 
abundance of the species in cave streams of the Sinkhole Plain (S.J. 
Taylor, INHS, in litt. 1998).

Previous Federal Action

    On May 22, 1984, the Service published a notice of review in the 
Federal Register (49 FR 21664) designating the Illinois cave amphipod 
as a category 2 candidate species. Category 2 was composed of taxa for 
which the Service had information indicating that threatened or 
endangered status might be warranted, but for which adequate data on 
biological vulnerability and threats indicated that listing was 
possibly appropriate, but for which data were not sufficient to support 
issuance of listing proposals. The species was again included as a 
category 2 candidate species in the notice of review published in the 
Federal Register (54 FR 554) on January 6, 1989. On November 21, 1991, 
the Service published a notice of review in the Federal Register (56 FR 
58804) designating the species as a category 1 candidate. Category 1 
taxa were those for which the Service had substantial biological 
information on hand to support proposing to list the species as 
threatened or endangered. The species was again included as a category 
1 candidate species in a notice of review published in the Federal 
Register (59 FR 58982) on November 15, 1994. On February 28, 1996, the 
Service published a notice of review in the Federal Register (61 FR 
7596) which eliminated the several candidate category designations of 
previous notices and identified the amphipod as a candidate species 
with a listing priority of 2. On July 28, 1997, the Service published 
the proposed rule (62 FR 40319) to list the Illinois cave amphipod as 
endangered. The Service reopened the public comment period on October 
9, 1997, (62 FR 52679) for 60 days at the request of the Illinois Farm 
Bureau Federation, the St. Clair County

[[Page 46902]]

Farm Bureau Federation, the Growmark Corporation, and Congressman Jerry 
F. Costello, because seasonal agricultural activities may have made it 
difficult for some interested and potentially affected parties to 
prepare and submit timely comments on the proposal. That comment period 
closed on December 8, 1997.
    The processing of this final rule conforms with the Service's 
revised Listing Priority Guidance published in the Federal Register (63 
FR 25502) on May 8, 1998. The Guidance revised the order in which the 
Service will process rulemakings during fiscal years 1998 and 1999. The 
Guidance calls for giving highest priority to handling emergency 
listings (Tier 1) and second highest priority (Tier 2) to all other 
listing actions except the designation or revision of critical habitat. 
Critical habitat designations or revisions are Tier 3 actions. 
Processing of this final rule falls under Tier 2.

Summary of Comments and Recommendations

    In the July 28, 1997, proposed rule and October 9, 1997, notice 
reopening the comment period, all interested parties were requested to 
submit factual reports or information that might contribute to the 
development of a final rule. Appropriate Federal and state agencies, 
county governments, scientific organizations, agricultural 
organizations, and other interested parties were contacted and 
requested to comment. Newspaper notices were published in local and 
regional newspapers across the range of the species inviting public 
comment.
    The Service received comments from 27 individuals and organizations 
during the comment periods; some parties provided more than one comment 
letter. Eight commenters supported the proposal. Twelve parties 
expressed concern over the possible effect the listing may have on 
their area of interest (agriculture or cave visitation), and several 
offered rebuttals to the Service's rationale but did not directly 
oppose the proposal. Four commenters expressed opposition to the 
proposal.
    Written comments received during the comment periods are addressed 
in the following summary. Comments of a similar nature are grouped 
together.
    Issue 1: The Federal Government, and hence the Service, does not 
have the authority to list a species found in only one State, because 
regulation of such species does not impact upon interstate commerce.
    Service Response: A December 5, 1997, decision by the U.S. Court of 
Appeals for the District of Columbia Circuit, National Association of 
Home Builders et al. v. Babbitt, 130 F.3d 1041 (D.C. Cir. 1997), a case 
challenging protection of the Delhi Sands flower-loving fly under the 
Act, addressed this issue. The ruling affirms Congress' authority to 
protect endangered species whose range is limited to a single State. 
The Court clearly recognized that the extinction of even a single 
species may have significant effects on the health of an ecosystem and 
ultimately on the commerce of the nation.
    Issue 2: Little information exists on the value of this species to 
humans.
    Service Response: Congress did not make a distinction between those 
species that are currently known to have some commercial or economic 
value and those that do not; the Act applies to all species in danger 
of extinction. Economic or commercial value is not a consideration in a 
listing decision. However, the Service realizes that it is difficult to 
describe the need to protect a species that most people will never see 
and that has no obvious economic, commercial, recreational, or 
aesthetic value. One of Congress' underlying principles when enacting 
the Act was that allowing any species to go extinct could result in 
unforeseeable adverse effects, because we may not know what 
contribution that species later may be found to have for the good of 
humans. There are many examples of plant and animal species that have 
been found useful in the treatment of diseases or in scientific 
research that provide benefits. Once a species becomes extinct, that 
potential benefit is lost forever.
    From an ecological perspective, an amphipod belongs to a group of 
species called detritivores that consume dead and decaying organic 
matter, recycling their nutrients back into the environment. Nutrient 
recycling is a critically important function in all ecosystems, 
especially nutrient-poor cave ecosystems. Amphipods can also be 
considered to be indicator species, that is, species especially 
sensitive to physical and chemical changes in their habitat, which can 
tell us when there is something critically wrong in their environment, 
and ours.
    Issue 3: The Service lacks the scientific data to justify listing 
this species since there has been inadequate sampling conducted: one 
cave in which the species historically occurred could not even be 
surveyed.
    Service Response: The Service believes that the sampling efforts 
conducted in 1993 and 1995 were by far the most intensive and extensive 
to date, and were appropriate to demonstrate the decline in the 
species' range with a high degree of certainty. In 1995 the INHS 
sampled 25 caves in the Illinois Sinkhole Plain and found Gammarus 
acherondytes in only 3 caves (Webb et al. 1993, Webb 1995). In 1 cave 
that historically contained G. acherondytes, for example, a total of 
561 amphipods from other species were collected without collecting any 
G. acherondytes. In a second cave that historically contained the 
species, 673 amphipods were collected without taking any G. 
acherondytes. If it is present in either of these caves, it would have 
to be extremely rare, constituting less than 2 individuals per 1000 
amphipods sampled. By comparison, G. acherondytes appeared in higher 
numbers in much smaller amphipod samples in Fogelpole Cave (at a rate 
of more than 50 individuals per 1000 sampled) and Illinois Caverns (at 
a rate of about 250 individuals per 1000 sampled). If the species is 
present in significant numbers in the other 2 caves, it should have 
been readily collected in mainstream samples at the level of sampling 
intensity that was carried out in the 1993 and 1995 surveys. More 
intensive collecting, in which thousands of amphipod specimens are 
taken from each cave for later identification, might be inappropriate 
and probably unhealthy for the cave community. Such intensive 
collecting might decimate or extirpate an amphipod species whose 
numbers already are extremely low. Although survey data cannot 
unequivocally prove that the species is extirpated from any cave, they 
demonstrate that the most optimistic scenario is that the species is 
extremely rare, and its numbers have decreased since the surveys done 
prior to 1993.
    The Service recognizes that the species may still occur in the one 
cave whose entrance has been closed by the landowner, and we have not 
made the assumption that it has been extirpated from that location. 
However, even if it does still occur there, the data indicate that the 
species' range has decreased from six caves to three or four.
    Issue 4: Recent sampling efforts have yielded more specimens than 
previous efforts, indicating that species numbers may actually be 
increasing.
    Service Response: The Service acknowledges a remote possibility 
that the species may be found in other cave streams in the sinkhole 
plain. There is also a chance that it may be found in other locations 
within Fogelpole Cave and Illinois Caverns. However, the Service 
believes the sampling effort that was expended looking for this species 
is more than adequate and reasonably reflects the relative abundance 
and diminishing distribution of the species in cave streams of the 
sinkhole plain.

[[Page 46903]]

The Service does intend to keep looking for this species in other 
locations, however.
    With regard to estimating the actual population of this species, 
the Service acknowledges that it is not likely to ever achieve that 
goal, regardless of the amount of effort put into surveys. The nature 
of this species and its habitat make it difficult, at best, to survey 
for it. Furthermore, the current identification technique for the 
species requires that it be sacrificed. It would be counter productive 
to sacrifice substantial numbers of an extremely rare species in order 
to obtain a more precise population estimate.
    However, obtaining an accurate estimate of species numbers is not 
necessary for the Service to determine that the species warrants 
protection under the Act. What must be demonstrated is that its range 
has been significantly reduced and the threats to the species continue 
and can reasonably be expected to result in a further decline. An 
accurate population estimate also is not necessary to establish and 
achieve recovery goals for the species. Recovery can be achieved by 
protecting the quality of its habitat and by restoring stable and 
viable populations to the caves from which it has been extirpated. Once 
listed, the amphipod's relative abundance and population trend will be 
monitored safely using standard scientific methods.
    Issue 5: The data do not conclusively show that agricultural 
chemicals are a threat to the species. Test data from the Monroe-
Randolph Bi-County Health Department do not support the conclusion that 
groundwater is polluted. Contamination from pesticides is currently 
within acceptable limits and is likely to decline as agricultural Best 
Management Practices are implemented in the area.
    Service Response: The Service agrees that more research needs to be 
done to further define the relative importance of agricultural 
chemicals as a threat to the species as compared to septic systems, 
livestock wastes, and the application of residential pesticides and 
fertilizers. However, the Service believes that all these sources 
contribute to the problem of groundwater degradation in the Sinkhole 
Plain. Research by Panno et al. (1996) as well as data obtained from 
the Monroe-Randolph Bi-County Health Department (ibid.), which tests 
drinking water supplies for nitrates and bacterial contamination, 
clearly demonstrate that groundwater degradation in the sinkhole plain 
is human-caused. In addition, pesticide levels may be within acceptable 
limits during most of the year, however, it has been demonstrated that 
peak levels during spring and summer rainstorm events are much higher 
and may be lethal to the species.
    One of the Service's peer reviewers of the proposed rule suggested 
that the primary threats to the species is a reduction in dissolved 
oxygen content of the stream which, at times, may fall below life-
sustaining levels. To a limited extent, this is a natural phenomenon 
which occurs during a rainstorm event, and cave stream fauna can 
survive these short-term depressions provided the dissolved oxygen 
content does not reach lethal levels. However, as a result of human 
activities water now runs off the land more rapidly causing a greater 
depression of ambient dissolved oxygen in the cave stream and providing 
for dissolved oxygen content to reach lethal levels faster.
    Agricultural chemicals can be lethal at certain concentrations, 
have chronic effects such as inhibiting reproduction, or leave the 
amphipod in a weakened condition and less able to cope with short-term 
depressions of dissolved oxygen (Thomas Aley, Ozark Underground 
Laboratory, in litt. 1997). Water sample analyses from springs, wells, 
and cave streams in the vicinity of these six caves, including one with 
the species still extant (Fogelpole), have found alachlor and atrazine, 
the latter at levels approaching those known to cause reproductive 
impairment in another amphipod species (Panno et al. 1996). DDE and 
dieldrin also were detected in invertebrate samples from Fogelpole 
Cave. There are also high levels of fecal coliform and enterococcus 
bacteria present; bacterial species which suggest both human and 
livestock sources.
    The Service, in conjunction with the Illinois Department of 
Conservation, is funding a cave recharge study to delineate the areal 
extent of the watersheds of the three caves in which the species is 
found. This crucial first step will enable the Service to evaluate the 
land uses in the watersheds, determine the relative extent and nature 
of contaminant inputs to the groundwater, and identify the primary 
locations of these inputs. Furthermore, additional water quality 
testing and tissue analyses will be conducted to determine the levels 
at which contaminants cause mortality and/or changes in critical 
biological functions such as reproduction. With these data, the Service 
will be better able to address the threats to the species and to 
propose solutions in a recovery plan.
    Issue 6: Urbanization and septic waste may be a greater threat than 
agriculture. The application of pesticides on residential properties 
was proposed for exemption from the takings provisions of section 9 of 
the Act, but such applications are not as well regulated or monitored 
as agricultural applications and may, therefore, have a more 
significant impact on the amphipod.
    Service Response: Due to inadequate data on the impacts of 
residential property pesticide use, and in response to public comments, 
the Service has modified the listing of activities that may potentially 
result in a violation of section 9 of the Act (see Available 
Conservation Measures section).
    Issue 7: The species' decline may be due to natural causes.
    Service Response: The Service acknowledges that there may be 
natural causes, such as severe weather or changing climatic conditions, 
contributing to the decline and extinction of any species. However, 
other likely causes were identified during the status assessment for 
this species. There is evidence that the deterioration of groundwater 
quality in the area coincides with an increase in residential 
development. There is further evidence that certain agricultural 
chemicals such as atrazine, which cause mortality in related amphipod 
species, are at or near lethal levels in the groundwater during certain 
periods. These factors indicate a human component to the decline of the 
species which is not a natural or cyclical phenomenon.
    Issue 8: Metal ions found in amphipod tissue are not evidence of 
harm.
    Service Response: The Service concurs with this statement. However, 
since several metal ions have been detected in amphipod tissues, the 
potential exists for acute or chronic effects to the species. The 
Service acknowledges that additional research is required to determine 
the nature and extent of any threat to the species that may be caused 
by metal ions in their environment.
    Issue 9: Listing the amphipod will shut down farming in the area.
    Service Response: The Service has no intention of halting farming 
in the Sinkhole Plain. We expect that any detrimental impacts on the 
amphipod due to agriculture can be reduced to a large extent through 
modest and localized land treatments, such as maintaining buffer strips 
around sinkholes, ensuring that chemicals are not dumped or spilled 
into sinkholes, and ensuring that livestock wastes do not leak or are 
not diverted into sinkholes. The Service will work with the Natural 
Resources Conservation

[[Page 46904]]

Service (NRCS), local agricultural representatives, and landowners to 
develop voluntary Conservation Agreements to implement Best Management 
Practices designed to protect surface and ground water quality. A 
similar approach will be applied to residential developments which 
might otherwise allow septic waste to be directed into sinkholes. The 
Service will work with developers, local planning and zoning boards, 
and health departments to develop alternatives to such practices.
    Issue 10: Programs are currently in place which will reduce the 
threat of contaminants to the amphipod.
    Service Response: The Service agrees that there are programs in 
place to reduce the threat of contaminants to the amphipod. However, 
many of these programs are voluntary, and the results of their 
implementation have been inadequately monitored and evaluated. Our hope 
is to expand, monitor, and improve upon existing programs to ensure a 
higher degree of participation and success.
    Issue 11: Listing the species may limit the visitation of caves by 
the public.
    Service Response: The proposed rule identified human use and 
visitation of caves as a potential threat to the species. However, 
whether this threat is significant depends on the level of use and the 
nature of the visitations. The Service will work with caving 
organizations such as the Illinois Speleological Society, as well as 
the Illinois Department of Natural Resources (DNR), to investigate the 
significance of cave visitation as a threat to the species and to 
develop measures to minimize any such threat. If cave visitation is 
found to be a significant threat to the survival and recovery of the 
amphipod, we will seek mutually acceptable measures to protect the 
species while minimizing any impact on cave visitation. We recognize 
the importance of caves such as Fogelpole and Illinois Caverns to the 
speleological community and have no intention of limiting cave 
visitation unless such limitations are necessary for the species' 
survival and recovery.

Peer Review

    In accordance with policy promulgated July 1, 1994 (59 FR 34270), 
the Service solicited the expert opinions of independent specialists 
regarding pertinent scientific or commercial data relating to the 
supportive biological and ecological information for species under 
consideration for listing. The purpose of such review is to ensure 
listing decisions are based on scientifically sound data, assumptions, 
and analyses, including input of appropriate experts and specialists.
    Following the publication of the listing proposal, the Service 
solicited the comments of two biologists having recognized expertise in 
invertebrate zoology and one individual having recognized expertise in 
karst hydrology and underground environments and requested their review 
of the available data concerning the Illinois cave amphipod. In order 
to ensure an unbiased examination of the data, the Service selected 
individuals who had only minor or no involvement in previous 
discussions on the possible listing of the species.
    Comments were received from all three peer reviewers within the 
comment period. The two biological reviewers concurred with the Service 
on factors relating to the taxonomic, biological, and ecological 
information and concurred with the proposal to list the Illinois cave 
amphipod as an endangered species. The karst hydrologist provided 
additional clarification of the importance of oxygen depletion as the 
primary mechanism by which the species is being harmed. That reviewer 
also concurred that the Illinois cave amphipod is in danger of 
extinction in the foreseeable future.

Summary of Factors Affecting the Species

    Section 4 of the Act and regulations (50 CFR part 424) promulgated 
to implement the listing provisions of the Act set forth the procedures 
for adding species to the Federal lists. A species may be determined to 
be threatened or endangered due to one or more of the five factors 
described in section 4(a)(1). These factors and their application to 
the Illinois cave amphipod (Gammarus acherondytes) of are as follows:

A. The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range

    The degradation of habitat through the contamination of groundwater 
is believed to be the primary threat to the Illinois cave amphipod. 
Karst terrain, where this amphipod is found, is a geologic land 
formation typified by sinkholes and fissures that provide direct and 
rapid conduits for water and water-borne material from the surface to 
the groundwater, thereby avoiding the filtering and cleansing 
mechanisms normally provided by overlying soils. Water movement from 
the land surface to the water table in karst terrain often is nearly 
instantaneous, and flood pulses following a rainstorm may cause levels 
of contaminants to become transiently higher (Libra et al. 1986), up to 
10,000 times higher than before the event (Quinlan and Alexander 1987).
    There are several sources of groundwater contamination affecting 
the amphipod's habitat: (1) the application of agricultural chemicals, 
evidence of which has been found in spring and well water samples in 
Monroe County (Panno et al. 1996); (2) bacterial contamination from 
human and animal wastes, which finds its way to subsurface water via 
septic systems, the direct discharge of sewage waste into sinkholes, or 
from livestock feedlots (Panno et al. 1996); (3) the application of 
residential pesticides and fertilizers; and (4) the accidental or 
intentional dumping of a toxic substance into a sinkhole.
    The primary mechanism threatening the species is believed to be a 
reduction in the dissolved oxygen content of underground cave streams 
which, at times, may fall below life-sustaining levels. To a certain 
extent, this is a natural phenomenon which occurs during a rainstorm 
event. Stormwater runoff is typically low in dissolved oxygen, and when 
it enters the groundwater, it depresses the ambient dissolved oxygen 
level in the cave stream. Under natural conditions, cave stream fauna 
can survive these short term, probably rare, depressions which may 
reach lethal levels.
    However, human activities on the land surface have resulted in 
changes to this natural condition that make lethal levels of depressed 
ambient dissolved oxygen more common. With agricultural, residential, 
and municipal development, stormwater now runs off the land more 
rapidly, reducing the time in which it reaches underground streams. 
Because of this more rapid runoff, the ambient dissolved oxygen in the 
cave stream will be depressed to a greater degree and can reach lethal 
levels faster. Furthermore, pesticides typically bind to soil 
particles; with the loss of vegetated buffers around sinkholes and 
fissures, more soil particles erode from the land surface and enter the 
groundwater carrying more pesticides with them. In addition, nitrogen-
based fertilizers and organic wastes increase the demand for dissolved 
oxygen to accomplish biochemical breakdown. These factors exacerbate 
the natural depression of dissolved oxygen levels. Furthermore, 
agricultural chemicals may either be lethal in themselves at certain 
concentrations, have chronic effects such as inhibiting reproduction, 
or can leave the amphipod in a weakened condition and less able to cope 
with short term depressions of dissolved oxygen.

[[Page 46905]]

    The most commonly used herbicides (and their proprietary names) in 
Monroe County are atrazine, alachlor (Lasso), cyanazine (Bladex), 
metolachlor (Dual), glyphosate (Roundup), 2,4-D, imazaquin (Scepter), 
imazethapyr (Pursuit), and pendimethalin (Prowl) (Omar Koester, 
University of Illinois Extension Service, in litt. 1996). The Illinois 
State Geological Survey analyzed water samples from 9 springs, 1 cave 
stream, and 33 wells in Monroe County for bacteria and pesticides to 
determine if contamination is occurring (Panno et al. 1996). The 
agricultural herbicides atrazine and/or alachlor were detected in 83 
percent of groundwater samples taken from springs in the study area. 
The levels of these herbicides in samples often exceeded the U.S. EPA 
Maximum Contaminant Levels of 2.0 parts per billion (ppb) and 3.0 ppb, 
respectively, during and following spring rainfalls. They reported 
maximum atrazine levels in spring samples as high as 98 ppb with the 
maximum level in Illinois Caverns being 1.38 ppb (Panno et al. 1996). 
Macek et al. (1976) observed acute toxicity to the amphipod Gammarus 
fasciatus from a 48-hour exposure to the herbicide atrazine at 2.4 
parts per million (ppm). In addition, they reported reproductive 
effects and impaired survival of offspring from concentrations as low 
as 0.14 ppm of atrazine during chronic tests lasting 30,119 days (Macek 
et al. 1976).
    The most commonly used insecticides in the region include carbaryl, 
carbofuran, chlorpyrifos, malathion, permethrin, methyl parathion, and 
phosmet. Mayer and Ellersieck (1986) reported that Gammaridae were most 
sensitive to the five insecticides carbaryl, DDT (dichloro-diphenyl-
trichloroethane), endrin, malathion, and methoxychlor and postulated 
that pesticide pulses characteristic of karst springs could have major 
impacts on biota such as amphipods. Webb et al. (1993) analyzed 
amphipod and isopod tissue samples from numerous caves, including the 
three caves known to contain the amphipod, for pesticides and PCB's 
(polychlorinated biphenyls). DDE (dichlorodiphenyl-dichloroethylene) 
and DDD (1,1-dichloro,-2,2-bis(p-chloro-phenyl) ethane) (breakdown 
products of DDT) were detected in isopods from Fogelpole Cave, 
reflecting the historical use of the insecticide DDT in the drainage 
basin. In addition, dieldrin, the persistent breakdown product of the 
insecticide aldrin, was detected in invertebrate samples from Fogelpole 
Cave. Both DDT and aldrin have been banned from use in the United 
States since 1973 and 1974, respectively. These data demonstrate some 
of the long term detrimental effects that agricultural chemicals can 
have on cave ecosystems. Interestingly, neither DDD, DDE, nor dieldrin 
were detected in water samples from Fogelpole Cave, supporting the 
premise that cave invertebrates accumulate and concentrate these toxins 
even though they do not exist at detectable levels in the cave water: 
cave invertebrates, therefore, serve as indicators of past and present 
contamination.
    Research by Panno et al. (1996) as well as data from the Monroe-
Randolph Bi-County Health Department (ibid.), which tests drinking 
water supplies for nitrates, clearly demonstrate that groundwater in 
the Sinkhole Plain contains anomalously large concentrations of nitrate 
(NO3-). Levels above 1.4 mg/L are assumed to be 
human-caused, and the main sources of nitrates are agricultural 
fertilizers, septic systems, and livestock wastes. Panno et al. (1996) 
found that the greatest range of nitrate concentrations in water 
samples from springs occurred around the time of spring planting, but 
it was concluded that nitrates in the shallow karst aquifer came from 
multiple sources.
    Webb et al. (1993) also found detectable quantities of bromide, 
fluoride, sulfate, and nitrate in Illinois Caverns and Fogelpole Cave. 
In addition, they found detectable concentrations of calcium, sodium, 
magnesium, iron, manganese, silicon, and barium in water samples from 
Fogelpole Cave, and these plus aluminum, potassium, and phosphorus in 
Illinois Caverns. In amphipod tissue samples from Fogelpole Cave, they 
reported detectable concentrations of aluminum, boron, barium, calcium, 
chromium, copper, iron, potassium, magnesium, manganese, sodium, 
phosphorus, and zinc (Webb et al. 1993). The six highest ranked metals 
detected in amphipod samples were also the six highest ranked metals 
detected in water samples, indicating an apparent relationship between 
the concentrations of these metals in tissue and water. The acute and 
chronic effects of these ions on the Illinois cave amphipod are 
currently unknown, but their presence in amphipod tissues and the water 
samples provides evidence of potential harm.
    In addition to chemical contamination, Panno et al. (1996) report 
that all springs and cave streams they sampled, as well as 29 of 33 
wells, contained concentrations of coliform, fecal coliform, 
enterococcus, and numerous other bacterial species that exceeded 
Federal drinking water standards. The bacterial species present 
strongly suggest contamination from both human and livestock sources. 
Prior to 1988, private and aeration-type septic systems were allowed to 
discharge directly into sinkholes, and most of those systems are still 
in existence. Although the practice was prohibited in 1987, exceptions 
are still granted in the study area (Panno et al. 1996).
    In his studies, Poulson (1991) concluded that bacterial pollution 
from human and livestock wastes has varying degrees of impact on cave 
biota. At high levels of contamination, a high biochemical oxygen 
demand (BOD) kills all macroscopic organisms and leaves only strands of 
colonial sewage bacteria and associated protozoa. If the BOD is high 
but does not completely remove oxygen, then tubificid sewage worms 
become part of the faunal community. If the amount of wastes is not too 
great, as with the diffuse input from septic fields, the sewage fauna 
is only minimally developed, but the increased organic food supply 
favors survival and reproduction of shorter-lived non-cave-dependent 
macrofauna which may replace cave-dependent species. If the input of 
waste decreases later, chironomid midges and other non-cave-dependent 
species survive but can no longer reproduce, while the reproduction of 
short-lived cave-dependent isopods and flatworms is stimulated. At 
still lower impact levels, the reproduction of larger cave-dependent 
species, like crayfish, may also be stimulated.
    The effects of bacterial contamination on the Illinois cave 
amphipod have not been studied. However, bacterial contamination is 
evidence of water quality degradation and could pose a threat to the 
species. Monroe County is within commuting distance of the St. Louis, 
Missouri, metropolitan area and is rapidly undergoing residential 
development. In fact, the increase in bacterial contamination of well 
water in the county coincided with the onset of accelerated development 
about 1987 (Poulson 1991). It is likely that the increase in bacterial 
contamination was the result of the installation of private septic 
systems in areas with soils of limited waste assimilation capacity and 
inadequate thickness, and the installation of systems that discharge 
septic effluent directly into sinkholes (Joan Bade, Monroe-Randolph Bi-
County Health Department, Waterloo, IL., pers. comm. 1996).
    The toxicity of contaminants to cave-dwelling species may be quite 
different than the response of their surface-

[[Page 46906]]

dwelling relatives, making the results of chemical analysis difficult 
to interpret. Due to their adaptations to a narrow range of 
environmental conditions, obligate cave species may be hypersensitive 
to chemical changes in ways that are not detectable by standard 
toxicity tests (Poulson 1991). Contaminants known to be toxic to 
amphipods and other crustaceans have been shown to be present and 
increasing in cave streams in the local area. While direct mortality 
cannot be conclusively attributed to such agricultural chemicals as 
atrazine, carbaryl, DDT, or malathion, or to bacterial contamination, 
the presence of such contaminants in the amphipod's environment 
constitutes strong circumstantial evidence that the deterioration of 
water quality is the primary cause of the decrease in the species' 
range and the number of extant populations.
    Human utilization of cave environments is a potential threat to 
this species. The accidental or intentional introduction of materials 
toxic to this species and habitat disturbance are potential hazards to 
the species during public visits to caves. None of the caves occupied 
by the amphipod have improved pedestrian walkways, and visitors must 
pass through the cave streams to access deeper passages. Such 
activities can physically disturb cave stream habitat, but the 
subsequent impact on the amphipod is unknown. Cave ecosystems are 
considered to be delicate.
    The State of Illinois owns the main entrances to Illinois Caverns 
and Fogelpole Cave and manages them as satellites of the Kaskaskia 
River State Fish and Wildlife Area. The State allows a maximum of 25 
individuals at a time to enter Illinois Caverns unsupervised, provided 
they obtain a permit and agree to conditions that prohibit littering or 
removal of biological materials. The Caverns are staffed during 
business hours by an on-site attendant. The main entrance to Fogelpole 
Cave, a dedicated Nature Preserve, is gated. The State does not allow 
any visitation of this cave except by permit for scientific purposes. 
Three privately owned entrances to a third cave containing the amphipod 
have also been dedicated as Illinois Nature Preserves. Such dedication 
implements landowner agreements to preserve and maintain existing 
conditions at these sites.

B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    Overexploitation or scientific collecting are not believed to be 
factors affecting the species' continued existence at this time, but 
the Federal listing will prohibit unauthorized collection of 
individuals of the species. Exact numbers are unknown, but at a minimum 
139 specimens have been collected from 6 caves over a 55-year period. 
Protection from collection may become important because collectors may 
seek the species once it becomes listed.

C. Disease or Predation

    The importance of these factors is presently unknown.

D. The Inadequacy of Existing Regulatory Mechanisms

    This species currently has no protection under Federal law. The 
Federal Cave Resources Protection Act of 1988 (16 U.S.C. 4301-4309; 102 
Stat. 4546) seeks to secure, protect, and preserve significant caves on 
Federal lands for the perpetual use, enjoyment, and benefit of all 
people. However, at this time, the Cave Resources Protection Act 
provides no protection to any caves containing, or potentially 
containing, Illinois cave amphipods, because none of the caves are on 
or under Federal land or are located in the immediate vicinity of 
Federal ownership. Therefore, these caves are ineligible for Federal 
protection under the Cave Resources Protection Act.
    The Illinois cave amphipod is listed as an endangered species under 
the Illinois Endangered Species Protection Act. As such, it is 
protected from direct taking (i.e., injury or mortality) regardless of 
whether it is on public or private land. However, ``take'' under State 
law does not include indirect harm through such mechanisms as habitat 
alteration. As long as the actions of private landowners are otherwise 
in compliance with the law, actions which destroy or degrade habitat 
for this species are allowed under Illinois law.
    State law requires consideration of this species during the 
planning processes of State agencies and local units of government 
which must consult with the Illinois DNR on the impacts of their 
proposed actions. The DNR will provide recommendations on how the 
impacts to the species can be avoided or minimized. The unit of 
government may accept or reject any or all recommendations (Illinois 
Administrative Code).
    As mentioned under Factor A of this section, several of the 
entrances to caves containing the species are dedicated as Illinois 
Nature Preserves which is the strongest land protection mechanism in 
Illinois. Such dedication restricts future uses of the land, in 
perpetuity, for the purpose of preserving the site in its natural 
state. The removal of biota from the site is prohibited except by 
permit and for scientific purposes only. Allowable uses of the site are 
limited to nonconsumptive, nondestructive activities. The landowner may 
decide whether to allow public access to the site, and management is 
accomplished in accordance with a master management plan prepared 
jointly by the Illinois Nature Preserves Commission and the landowner. 
Dedicated properties cannot be subdivided, and the dedication 
instrument is attached to the deed and recorded.
    Ownership or protection of cave entrances does not necessarily 
ensure protection of the caves' environment, particularly water 
quality. Water quality is largely a function of land use in the cave 
stream recharge areas on the land surface, and the vast majority of the 
watersheds of all caves containing the amphipod is in private 
ownership, and land use is primarily agriculture. Recharge areas may be 
several square miles in size, and runoff and seepage from thousands of 
acres of agricultural land may be funneled into one cave system, thus 
increasing the magnitude of any toxic hazard posed by the use of 
agricultural chemicals. The application of pesticides is regulated by 
the U.S. Environmental Protection Agency (EPA), and maximum allowable 
application levels and use restrictions are printed on pesticide 
container labels. While pesticides may be applied fully in compliance 
with the restrictions, adverse impacts to the species may still result 
in karst systems.
    Current State and local regulations are inadequate for protecting 
water quality in a sensitive geological formation like karst. St. Clair 
and Monroe counties are rapidly developing as residential communities 
for the St. Louis, Missouri, Metropolitan Area with most home sites 
being served by individual wells and septic systems. Septic systems may 
not perform as designed, and, in some cases, septic effluent drains 
directly into sinkholes. Studies have shown that there is no general 
housing density zoning in karst terrain that assures that groundwater 
quality will be protected when septic systems are used. The more houses 
there are in a spring or cave stream recharge area, the greater the 
chance that some of them will introduce contaminants into the 
groundwater system, and the greater the chance that one or more of the 
septic field systems will constitute a major source of groundwater 
contamination (Aley and Thompson 1984).

[[Page 46907]]

E. Other Natural or Manmade Factors Affecting Its Continued Existence

    Because of the low numbers of the Illinois cave amphipod and a 
highly restricted range, even the loss of a few individuals to natural 
events may be significant to the species' survival. As a group, aquatic 
amphipods have adapted to the extremes of natural events such as spring 
floods or high water discharges following rainstorms and, no doubt, 
some individuals are washed out of the cave environment during such 
events. Because the species is extant in only three or four cave 
systems within a relatively small geographic area, it is conceivable 
that a heavy spring snowmelt or rainstorm could cause a flushing of all 
systems at one time significantly affecting each population.
    The risk of extinction due to the threats to the Illinois cave 
amphipod (Gammarus acherondytes) posed by the above factors is 
exacerbated by the small number of low density populations that remain. 
Although Gammarus acherondytes was always rare, the current population 
densities are likely much lower (due to the previously identified 
threats) than historical levels. Despite any adaptations to conditions 
which result in rarity, habitat loss and degradation increase a 
species' vulnerability to extinction. Environmental variation, whether 
random or predictable, naturally causes fluctuations in populations. 
However, populations with small numbers are more likely to fluctuate 
below the minimum viable population (i.e., the minimum number of 
individuals needed for a population to survive). If population levels 
stay below this minimum size, an inevitable, and often irreversible, 
slide toward extinction will occur. Small populations are also more 
susceptible to inbreeding depression and genetic drift. Populations 
subjected to either of these problems usually have low genetic 
diversity, which reduces fertility and survivorship. Lastly, chance 
variation in age and sex ratios can affect birth and death rates. 
Changes to demographics may lead to death rates exceeding the birth 
rates, and when this occurs in small populations there is a higher risk 
of extinction.
    The Service has carefully assessed the best scientific and 
commercial information available regarding the past, present, and 
future threats faced by this species in determining to make this rule 
final. Based on this evaluation, the preferred action is to list the 
Illinois cave amphipod as endangered.

Critical Habitat

    Critical habitat is defined in section 3 of the Act as: (i) the 
specific areas within the geographical area occupied by a species, at 
the time it is listed in accordance with the Act, on which are found 
those physical or biological features (I) essential to the conservation 
of the species and (II) that may require special management 
considerations or protection; and (ii) specific areas outside the 
geographical area occupied by a species at the time it is listed, upon 
a determination that such areas are essential for the conservation of 
the species. ``Conservation'' means the use of all methods and 
procedures needed to bring the species to the point at which listing 
under the Act is no longer necessary.
    Section 4(a)(3) of the Act, as amended, and implementing 
regulations (50 CFR 424.12) require that, to the maximum extent prudent 
and determinable, the Secretary designate critical habitat at the time 
the species is determined to be endangered or threatened. Service 
regulations (50 CFR 424.12(a)(1)) state that designation of critical 
habitat is not prudent when one or both of the following situations 
exist--(1) the species is threatened by taking or other human activity, 
and identification of critical habitat can be expected to increase the 
degree of threat to the species, or (2) such designation of critical 
habitat would not be beneficial to the species. The Service finds that 
designation of critical habitat is not prudent for the Illinois cave 
amphipod.
    Critical habitat receives consideration under section 7 of the Act 
with regard to actions carried out, authorized, or funded by a Federal 
agency (see Available Conservation Measures section). As such, 
designation of critical habitat may affect activities on Federal lands 
and may affect activities on non-Federal lands where such a Federal 
nexus exists. Under section 7 of the Act, Federal agencies are required 
to ensure that their actions do not jeopardize the continued existence 
of a species or result in destruction or adverse modification of 
critical habitat. However, both jeopardizing the continued existence of 
a species and adverse modification of critical habitat have similar 
standards and thus similar thresholds for violation of section 7 of the 
Act. In fact, biological opinions that conclude that a Federal agency 
action is likely to adversely modify critical habitat but not 
jeopardize the species for which the critical habitat has been 
designated are extremely rare.
    Consultation is likely to occur with the NRCS and with the U.S. EPA 
for programs administered by those agencies. For a species extant in 
only three or four small, discrete populations, any significant adverse 
impact to its habitat would likely jeopardize the species' continued 
existence. Therefore, for this species the threshold for a jeopardy 
determination is indistinguishable from the threshold for determining 
adverse modification of critical habitat. For these reasons, the 
designation of critical habitat for the Illinois cave amphipod would 
provide no additional benefit to the species beyond that conferred by 
listing, and therefore, such designation is not prudent.
    The nature of karst terrain means that surface features such as 
sinkholes, fissures, and disappearing streams provide direct surface 
connections to the cave streams inhabited by the amphipod. Publishing a 
critical habitat map would delineate the recharge areas of these caves. 
The Service believes such a map would make it easy to locate the 
surface connections to the cave streams and could promote vandalism in 
the form of intentional introduction of toxic chemicals into the 
underground system. Although vandalism has not been documented as a 
past threat to the Illinois cave amphipod, listing it as an endangered 
species publicizes the present vulnerability of this species, and thus 
can be reasonably expected to increase the threat of vandalism or 
intentional destruction of the species' habitat. In light of the 
vulnerability of this species to vandalism or the intentional 
destruction of its habitat, publication of descriptions of habitat 
features and maps providing its precise locations within areas of 
accelerating development, as required for the designation of critical 
habitat, would reasonably be expected to increase the degree of threats 
to the species, increase the difficulties of enforcement, and further 
contribute to the decline of the Illinois cave amphipod. Designation of 
critical habitat for the Illinois cave amphipod would, therefore, 
provide no benefit to the species apart from the protection afforded by 
listing the plant as threatened.
    Protection of the habitat of the Illinois cave amphipod will be 
addressed through the section 4 recovery process and the section 7 
consultation process. Although this amphipod occurs only on private and 
State land, it may be affected by projects with Federal connections. 
The Service believes that activities involving a Federal action which 
may affect the Illinois cave amphipod can be identified without 
designating critical habitat, by providing Federal agencies with 
information on

[[Page 46908]]

the location of occupied habitat and recharge areas and information on 
the kinds of activities which could affect the species. For the reasons 
discussed above, the Service finds that the designation of critical 
habitat for Illinois cave amphipod is not prudent.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing results in public awareness and 
conservation actions by Federal, State, and local agencies, private 
organizations, and individuals. The Act provides for possible land 
acquisition and cooperation with the States and requires that recovery 
actions be carried out for all listed species. The protection required 
of Federal agencies and the prohibitions against taking and harm are 
discussed, in part, below.
    Section 7(a) of the Act requires Federal agencies to evaluate their 
actions with respect to any species that is proposed or listed as 
endangered or threatened, and with respect to its critical habitat, if 
any is being designated. Regulations implementing this interagency 
cooperation provision of the Act are codified at 50 CFR part 402. 
Section 7(a)(2) requires Federal agencies to confer informally with the 
Service on any action that is likely to jeopardize the continued 
existence of a proposed species or result in destruction or adverse 
modification of proposed critical habitat. If a species is subsequently 
listed, section 7(a)(2) requires Federal agencies to ensure activities 
they authorize, fund, or carry out are not likely to jeopardize the 
continued existence of such a species or to modify its critical 
habitat. If a Federal agency action may affect a listed species or its 
critical habitat, the responsible Federal agency must enter into 
consultation with the Service.
    Federal agency actions that may require consultation as described 
in the preceding paragraph include activities by the NRCS such as the 
Conservation Reserve Program, the Environmental Quality Incentive 
Program, and the Highly Erodible Land and Wetland Conservation 
provisions of the Food Security Act of 1985. These activities are 
expected to generally benefit the species through the protection of 
groundwater quality. In addition, consultation may be required with the 
U.S. EPA on the use of pesticides in the watersheds of the species' 
range.
    The Act and implementing regulations found at 50 CFR 17.21 set 
forth a series of general prohibitions and exceptions that apply to all 
listed wildlife. The prohibitions, as codified at 50 CFR 17.21, in 
part, make it illegal for any person subject to the jurisdiction of the 
United States to take (including harass, harm, pursue, hunt, shoot, 
wound, kill, trap, or collect; or to attempt any of these), import or 
export, ship in interstate commerce in the course of commercial 
activity, or sell or offer for sale in interstate or foreign commerce, 
any listed species. It also is illegal to possess, sell, deliver, 
carry, transport, or ship any such wildlife that has been taken 
illegally. Certain exceptions apply to agents of the Service and State 
conservation agencies.
    Permits may be issued to carry out otherwise prohibited activities 
involving endangered wildlife under certain circumstances. Regulations 
governing permits are at 50 CFR 17.22, 17.23, and 17.32. For endangered 
species, such permits are available for scientific purposes, to enhance 
the propagation or survival of the species, or for incidental take in 
connection with otherwise lawful activities.
    It is the policy of the Service, published in the Federal Register 
on July 1, 1994 (59 FR 34272), to identify to the maximum extent 
practicable at the time a species is listed, those activities that 
would or would not constitute a violation of section 9 of the Act. The 
intent of this policy is to increase public awareness of the effect of 
the listing on proposed and ongoing activities within a species' range. 
The Service believes that, based upon the best available information, 
the following actions will not result in a violation of section 9, 
provided these activities are carried out in accordance with existing 
regulations and permit requirements:
    (1) Construction and use of properly constructed and properly 
functioning sewer systems within the species' range.
    (2) Visitation of Fogelpole Cave by permitted individuals.
    (3) Agricultural activities outside of the recharge areas for caves 
known to contain Illinois cave amphipod.
    (4) Agricultural activities within the known recharge area of caves 
known to contain the Illinois cave amphipod if such activities 
incorporate Service-approved practices designed to protect surface and 
ground water quality. Such practices will include buffer strips around 
sinkholes and losing streams, diversion of animal wastes away from 
sinkholes and losing streams, and avoidance of agricultural chemical 
spills or disposal into sinkholes.
    Activities that the Service believes could potentially result in 
section 9 violation include, but are not limited to:
    (1) Use, application, or discharge of agricultural and residential 
chemicals, or other pollutants, particularly insecticides, onto plants, 
soil, ground, water, or other surfaces within the recharge areas of the 
species' range when conducted in violation of label directions, or 
following Service notification that such use, application, or discharge 
is likely to result in deterioration of cave water quality and harm to 
the species. Buffer zones, indicating areas within the recharge areas 
requiring special precautions for the Illinois cave amphipod, will be 
identified by the Service; maps of these buffer zones will be provided 
to the appropriate landowners and government officials.
    (2) Discharging of agricultural and residential chemicals or other 
pollutants including debris, garbage, trash, septic effluent, animal 
waste, or any other foreign material into sinkholes or fissures in the 
recharge areas of the species' range.
    (3) Construction of new private septic systems or any identified 
use of improperly functioning existing private septic systems in the 
recharge areas of the species' range, following Service notification 
that such construction or use is likely to cause significant water 
quality degradation and harm the species. The Service will provide a 
reasonable period of time to correct or mitigate such system 
deficiencies.
    (4) Impoundment, water diversion, draining, ditching, or 
discharging of fill material in wetlands, sinkhole lakes and ponds, 
sinkholes, fissures, and human-caused reduction or loss of streams 
within recharge areas of the species' range if such activities 
significantly adversely affect the supply or quality of water in the 
cave streams wherein the species is found and result in take or harm to 
the species.
    (5) Visitation or use of Illinois Caverns and other caves 
identified as containing this species following Service notification 
that such visitation or use is likely to cause the significant habitat 
degradation and/or harm to the species.
    Questions regarding whether specific activities may constitute a 
violation of section 9 should be directed to the Field Supervisor, Rock 
Island Field Office (see ADDRESSES section). Requests for copies of the 
regulations regarding listed species and inquiries about prohibitions 
and permits may be addressed to U.S. Fish and Wildlife Service, 
Division of Endangered Species, Whipple Federal Building, 1 Federal 
Drive, Ft. Snelling,

[[Page 46909]]

Minnesota 55111-4056 (telephone 612/713-5350; facsimile 612/713-5292).

National Environmental Policy Act

    The Service has determined that Environmental Assessments and 
Environmental Impact Statements, as defined under the authority of the 
National Environmental Policy Act of 1969, need not be prepared in 
connection with regulations adopted pursuant to Section 4(a) of the 
Act. A notice outlining the Service's reasons for this determination 
was published in the Federal Register on October 25, 1983 (48 FR 
49244).

Paperwork Reduction Act

    This rule does not contain any information collection requirements 
for which the Office of Management and Budget (OMB) approval under the 
Paperwork Reduction Act, 44 U.S.C. 3501 et seq. is required. An 
information collection related to the rule pertaining to permits for 
endangered and threatened species has OMB approval and is assigned 
clearance number 1018-0094. This rule does not alter that information 
collection requirement. For additional information concerning permits 
and associated requirements for threatened species, see 50 CFR 17.32.

References Cited

Aley, Thomas and K.C. Thomson. 1984. Septic fields and the 
protection of groundwater quality in Greene County, Missouri. Ozark 
Underground Laboratory. Springfield, MO. Pages 31-46.
Holsinger, John R. 1972. The freshwater amphipod crustaceans 
(Gammaridae) of North America. In: U.S. Envir. Protect. Agency 
Identification Manual No. 5., pages 17-27. Washington, D.C.
Hubricht, Leslie and J.G. Mackin. 1940. Descriptions of nine new 
species of fresh-water amphipod crustaceans with notes and new 
localities for other species. In: The Am. Midl. Nat. 23:192-193, and 
Fig. 2.
Illinois Administrative Code, Part 17, Section 1075.
Libra, R.D., G.R. Hallberg, B.E. Hoyer, and L.G. Johnson. 1986. 
Agricultural impacts on ground water quality: The Big Spring basin 
study, Iowa--agricultural impacts on ground water (Omaha, NE). Pages 
253-273. In: Proceedings, National Water Well Association, Dublin, 
OH.
Macek, K.J., K.S. Buxton, S. Sauter, S. Gnilka, and J.W. Dean. 1976. 
Chronic toxicity of atrazine to selected aquatic invertebrates and 
fishes. EPA-600/3-76-047. Environmental Research Laboratory, U.S. 
Envir. Protect. Agency, Duluth, MN. Reported in: Pesticide 
background statements, Vol. 1 Herbicides. U.S. Forest Service. 1984. 
Agricl. Handbook #633. Washington, D.C.
Mayer, Foster L. Jr. and M.R. Ellersieck. 1986. Manual of acute 
toxicity: interpretation and data base for 410 chemicals and 66 
species of freshwater animals. U.S. Dept. of the Int., Fish and 
Wildlife Service. Washington, D.C. 506 pp.
Panno, S.V., I.G. Krapac, C.P. Weibel, and J.D. Bade. 1996. 
Groundwater contamination in karst terrain of southwestern Illinois. 
Illinois State Geological Survey Environmental Geology Series Report 
151. Champaign, IL. 43 pp.
Poulson, T.L. 1991. Assessing groundwater quality in caves using 
indices of biological integrity. Pages 495-511. In: Proceedings of 
the Third Conference on Hydrology, Ecology, Monitoring and 
Management of Groundwater in Karst Terrains. December, 1991. 
Nashville, TN.
Quinlan, J.F. and E.C. Alexander. 1987. How often should samples be 
taken at relevant locations for reliable monitoring of pollutants 
from an agricultural, waste disposal, or spill site in a karst 
terrain? A first approximation. Pages 277-286. In: B.F. Beck and 
W.L. Wilson (eds.) Karst Hydro-geology: Engineering and 
Environmental Applications. Proceedings of the Second 
Multidisciplinary Conference on Sinkholes and the Environmental 
Impacts of Karst, Orlando, FL. 429 pp.
Webb, D.W., S.J. Taylor, and J.K. Krejca. 1993. The biological 
resources of Illinois caves and other subterranean environments. 
Technical Report 1993(8), Center for Biodiversity, Illinois Natural 
History Survey, Champaign, IL.
Webb, D.W. 1995. Status report on the cave amphipod Gammarus 
acherondytes Hubricht and Mackin (Crustacea: Amphipoda) in Illinois. 
Technical Report 1995 (22). Illinois Natural History Survey Center 
for Biodiversity, Champaign, IL. 22 pp.

    Author: The primary author of this final rule is Gerald Bade, Rock 
Island Field Office (see ADDRESSES section).

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 
recordkeeping requirements, Transportation.

Regulation Promulgation

    Accordingly the Service amends part 17, subchapter B of chapter I, 
title 50 of the Code of Federal Regulation, as set forth below:

PART 17--[AMENDED]

    1. The authority citation for part 17 continues to read as follows:

    Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C. 
4201-4245; Pub. L. 99-625, 100 Stat. 3500; unless otherwise noted.

    2. Section 17.11(h) is amended by adding the following, in 
alphabetical order under CRUSTACEANS to the list of Endangered and 
Threatened Wildlife:


Sec. 17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                        Species                                                    Vertebrate                                                           
--------------------------------------------------------                        population where                                  Critical     Special  
                                                            Historic range       endangered or         Status      When listed    habitat       rules   
           Common name                Scientific name                              threatened                                                           
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                        
      *                   *                   *                   *                   *                   *                   *                   *     
           Crustaceans                                                                                                                                  
                                                                                                                                                        
       *                   *                   *                   *                   *                   *                   *                        
Amphipod, Illinois cave..........  Gammarus              U.S.A. (IL)........  NA.................  E                       642           NA           NA
                                    acherondytes.                                                                                                       
                                                                                                                                                        
       *                   *                   *                   *                   *                   *                   *                        
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 46910]]

    Dated: August 22, 1998.
Jamie Rappaport Clark,
Director, Fish and Wildlife Service.
[FR Doc. 98-23729 Filed 9-2-98; 8:45 am]
BILLING CODE 4310-55-U