[Federal Register Volume 62, Number 243 (Thursday, December 18, 1997)]
[Rules and Regulations]
[Pages 66295-66304]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-33041]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
RIN 1018-AD28
Endangered and Threatened Wildlife and Plants; Final Rule To List
Three Aquatic Invertebrates in Comal and Hays Counties, TX, as
Endangered
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: The Fish and Wildlife Service (Service) determines three
aquatic invertebrate species known only from Comal and Hays counties,
Texas, to be endangered species under the Endangered Species Act of
1973, as amended (Act). The invertebrates to be listed are Peck's cave
amphipod (Stygobromus pecki), Comal Springs riffle beetle (Heterelmis
comalensis), and Comal Springs dryopid beetle (Stygoparnus comalensis).
The primary threat to these species is a decrease in water quantity and
quality as a result of water withdrawal and other human activities
throughout the San Antonio segment of the Edwards Aquifer. This action
implements Federal protection provided by the Act for these three
invertebrates.
EFFECTIVE DATE: January 20, 1998.
ADDRESSES: The complete file for this rule is available for inspection,
by appointment, during normal business hours at the Ecological Services
Field Office, U.S. Fish and Wildlife Service, 10711 Burnet Road, Suite
200, Austin, Texas 78758.
FOR FURTHER INFORMATION CONTACT: Ruth Stanford, Ecologist (see
ADDRESSES section) (512/490-0057; facsimile (512/490-0974).
SUPPLEMENTARY INFORMATION:
Background
The Service designates Peck's cave amphipod (Stygobromus pecki),
Comal Springs riffle beetle (Heterelmis comalensis), and Comal Springs
dryopid beetle (Stygoparnus comalensis) as endangered under the
authority of the Act (16 U.S.C. 1531 et seq.). These three aquatic
invertebrate species are restricted in distribution to spring sites in
Comal and Hays counties, Texas, and in the case of Peck's cave amphipod
and Comal Springs dryopid beetle, the associated aquifer. Peck's cave
amphipod is known from Comal Springs and Hueco Springs, both in Comal
County. The Comal Springs riffle beetle is known from Comal Springs and
San Marcos Springs (Hays County). The Comal Springs dryopid beetle is
known from Comal Springs and Fern Bank Springs (Hays County).
The water flowing out of each of these spring orifices comes from
the Edwards Aquifer (Balcones Fault Zone--San Antonio Region), which
extends from Hays County west to Kinney County. Comal Springs are
located in Landa Park, which is owned and operated by the City of New
Braunfels, and on private property adjacent to Landa Park. Hueco
Springs and Fern Bank Springs are located on private property. The San
Marcos Springs are located on the property of Southwest Texas State
University.
[[Page 66296]]
Peck's cave amphipod is a subterranean, aquatic crustacean in the
family Crangonyctidae. The Comal Springs riffle beetle is an aquatic,
surface-dwelling species in the family Elmidae. The Comal Springs
dryopid beetle is the only known subterranean member of the beetle
family Dryopidae. Elmid and dryopid beetles live primarily in flowing,
uncontaminated waters.
The first recorded specimen of the amphipod Stygobromus
(=Stygonectes) pecki (Holsinger 1967) was collected by Peck at Comal
Springs in June 1964. Reddell collected a second specimen at the same
place in May 1965. In 1967, Holsinger named the species Stygonectes
pecki, in Peck's honor, selecting the 1965 specimen as the type
specimen. Later he included all the nominal Stygonectes species in the
synonymy of the large genus Stygobromus. The Service has used ``cave
amphipod'' as a generic common name for members of this genus, and this
name was simply transliterated as ``Peck's cave amphipod'' without
reference to a particular cave.
Over 300 specimens of Peck's cave amphipod have been collected
since its description. Most specimens were netted from crevices in rock
and gravel near the three largest orifices of Comal Springs on the west
side of Landa Park in Comal County, Texas (Arsuffi 1993, Barr 1993).
Barr collected one specimen from a fourth Comal spring run on private
property adjacent to Landa Park and one specimen from Hueco Springs,
about 7 kilometers (km) (4 miles (mi)) north of Comal Springs (Barr
1993). Despite extensive collecting efforts, no specimens have been
found in other areas of the Edwards Aquifer.
Like all members of the exclusively subterranean genus Stygobromus,
this species is eyeless and unpigmented, indicating that its primary
habitat is a zone of permanent darkness in the underground aquifer
feeding the springs. Above ground, individuals are easy prey for
predators, but they usually take shelter in the rock and gravel
crevices and may succeed in reentering the spring orifice. Barr (1993)
got most specimens in drift nets at spring orifices and found them less
often as she moved downstream, supporting the notion that they may be
easy prey and do not likely survive for long outside the aquifer.
The Comal Springs riffle beetle is a small, aquatic beetle known
from Comal Springs and San Marcos Springs. It was first collected by
Bosse in 1976 and was described in 1988 by Bosse et al. The closest
relative of H. comalensis appears to be H. glabra, a species that
occurs farther to the west in the Big Bend region (Bosse et al. 1988).
Adult Comal Springs riffle beetles are about 2 millimeters (mm)
(\1/8\ inch (in)) long, with females slightly larger than males. Unlike
the other two organisms listed here, the Comal Springs riffle beetle is
not a subterranean species. It occurs in the gravel substrate and
shallow riffles in spring runs. Some riffle beetle species can fly
(Brown 1987), but the hind wings of H. comalensis are short and almost
certainly non-functional, making the species incapable of this mode of
dispersal (Bosse et al. 1988).
Larvae have been collected with adults in the gravel substrate of
the spring headwaters and not on submerged wood as is typical of most
Heterelmis species (Brown and Barr 1988). Usual water depth in occupied
habitat is 2 to 10 centimeters (cm)(1 to 4 in) although the beetle may
also occur in slightly deeper areas within the spring runs. Populations
are reported to reach their greatest densities from February to April
(Bosse et al. 1988). The Comal Springs riffle beetle has been collected
from spring runs 1, 2, and 3 at Comal Springs in Landa Park (springs j,
k, and l in Brune 1981) and a single specimen was collected from San
Marcos Springs 32 km (20 mi) to the northeast.
The Comal Springs dryopid beetle is a recently discovered species.
It was first collected in 1987 and described as a new genus and species
in 1992 by Barr (California State University) and Spangler (National
Museum of Natural History, Smithsonian Institution). Adult Comal
Springs dryopid beetles are about 3.0-3.7 mm (\1/8\ inch) long. They
have vestigial (non-functional) eyes, are weakly pigmented,
translucent, and thin-skinned. This species is the first subterranean
aquatic member of its family to be discovered (Brown and Barr 1988;
Barr, in litt. 1990; Barr and Spangler 1992).
Collection records for the Comal Springs dryopid beetle are
primarily from spring run 2 at Comal Springs, but they have also been
collected from runs 3 and 4 at Comal and from Fern Bank Springs about
32 km (20 mi) to the northeast in Hays County. Collections have been
from April through August. Most of the specimens have been taken from
drift nets or from inside the spring orifices. Although the larvae of
the Comal Springs dryopid beetle have been collected in drift nets
positioned over the spring openings, they are presumed to be associated
with air-filled voids inside the spring orifices since all other known
dryopid beetle larvae are terrestrial. Unlike Peck's cave amphipod, the
Comal Springs dryopid beetle does not swim, and it may have a smaller
range within the aquifer.
The exact depth and subterranean extent of the ranges of the two
subterranean species (Comal Springs dryopid beetle and Peck's cave
amphipod) are not precisely known because of a lack of methodologies
available for studying karst aquifer systems and the organisms that
inhabit such systems. Presumably an interconnected area, the
subterranean portion of this habitat, provides for feeding, growth,
survival, and reproduction of the Comal Springs dryopid beetle and
Peck's cave amphipod. However, no specimens of these species have
appeared in collections from 22 artesian and pumped wells flowing from
the Edwards Aquifer (Barr 1993) suggesting that these species may be
confined to small areas surrounding the spring openings and are not
distributed throughout the aquifer. Barr (1993) also surveyed nine
springs in Bexar, Comal, and Hays counties considered most likely to
provide habitat for endemic invertebrates and found Stygoparnus
comalensis only at Comal and Fern Bank springs and Stygobromus pecki
only at Comal and Hueco springs.
Although these species are fully aquatic and two of the three
require flowing water for respiration, the absolute low water limits
for survival are not known. They survived the drought of the middle
1950's, which resulted in cessation of flow at Comal Springs from June
13 through November 3, 1956. Hueco Springs is documented to have gone
dry in the past (Brune 1981, Barr 1993) and, although no information is
available for Fern Bank Springs, given its higher elevation, it has
probably gone dry as well (Glenn Longley, Edwards Aquifer Research and
Data Center, personal communication, 1993). San Marcos Springs has not
gone dry in recorded history.
These invertebrates were not extirpated by the only recorded
temporary cessation of spring flow. However, given that they are fully
aquatic and that no water was present in the springs for a period of
several months, they were probably negatively impacted. These species
are not likely adapted to surviving long periods of drying (up to
several years in duration) that may occur in the absence of a water
management plan for the Edwards Aquifer that accommodates the needs of
these invertebrates. Stagnation of water may be a limiting condition,
particularly for the Comal Springs dryopid beetle and Peck's cave
amphipod.
[[Page 66297]]
Stagnation of water and/or drying within the spring runs and the
photic (lighted) zone of the spring orifices would probably be limiting
for the Comal Springs riffle beetle because natural water flow is
considered important to the respiration and therefore survival of this
invertebrate species. Elmid and dryopid beetles have a mass of tiny,
hydrophobic (unwettable) hairs on their underside where they maintain a
thin bubble of air through which gas exchange occurs (Chapman 1982).
This method of respiration loses its effectiveness as the level of
dissolved oxygen in the water decreases. A number of aquatic insects
that use dissolved oxygen rely on flowing water to obtain oxygen.
Previous Federal Action
In a petition dated September 9, 1974, the Conservation Committee
of the National Speleological Society requested the Service to list
Stygobromus (=Stygonectes) pecki. The species was included in a notice
of review published on April 28, 1975 (40 FR 18476). A ``warranted but
precluded'' finding regarding several species in that petition was made
on October 12, 1983, and published on January 20, 1984 (49 FR 2485). A
warranted but precluded finding means that available information
indicates listing the species as threatened or endangered is
appropriate but that the listing is precluded by higher priority
actions. The same determination has been repeated for Peck's cave
amphipod in subsequent years. The species was included as a category 2
candidate in comprehensive notices of review published on May 22, 1984
(49 FR 21664), January 6, 1989 (54 FR 554), and November 21, 1991 (56
FR 58804). Category 2 candidates were those species for which data in
the Service's possession indicated that listing was possibly
appropriate, but for which substantial data on biological vulnerability
and threats were not known or on file to support proposed rules.
Stygobromus pecki was elevated to category 1 status in the 1994 notice
of review (59 FR 58982). Category 1 candidates were those species for
which the Service had on file substantial information on biological
vulnerability and threats to support a proposal to list. As published
in the Federal Register on February 28, 1996 (61 FR 7596), candidate
category 2 status was discontinued and only category 1 species are
currently recognized as candidates for listing purposes.
In a petition dated June 20, 1990, and received June 21, 1990, Mr.
David Whatley, then Director of the City of New Braunfels Parks and
Recreation Department, requested that the Service list five
invertebrate taxa, including Peck's cave amphipod and four insects. The
Service treated this as a second petition for the amphipod. A notice of
finding published April 29, 1991 (56 FR 19632), announced that the
petition presented substantial information and that listing the Comal
Springs riffle beetle and the Comal Springs dryopid beetle may be
warranted. Formal status review was initiated for those species. Both
species became candidates for listing in the 1994 notice of review (59
FR 58982).
Peck's cave amphipod, Comal Springs riffle beetle, and Comal
Springs dryopid beetle were proposed for listing on June 5, 1995 (60 FR
29537). The Act requires that a final determination on a proposed
listing be made within one year of the proposal. However, a
congressionally-imposed moratorium on final listing actions combined
with a recision of funding for the Service's listing program prohibited
timely publication of this final rule.
Summary of Comments and Recommendations
In the June 5, 1995, proposed rule (60 FR 29537) and associated
Federal Register notices all interested parties were requested to
submit factual reports or information to be considered in making a
final listing determination. Appropriate Federal and State agencies,
local governments, scientific organizations, and other interested
parties were contacted and requested to comment.
A public hearing request came from Mr. David Langford, Executive
Vice President of the Texas Wildlife Association, by letter dated June
22, 1995. The hearing was held on July 24, 1995 at the New Braunfels
Civic Center in New Braunfels, Texas. Legal notices of the public
hearing, which invited general public comment, were published in The
New Braunfels Herald-Zeitung, the San Marcos Daily Record, the Uvalde
Leader-News, the Medina Valley-Times, and the San Antonio Express-News.
Sixteen people attended the public hearing and one person provided oral
testimony.
The Service received 1 oral and 24 written comments on the
proposal. Of the letters and oral testimony received, nine supported
the proposed action, seven opposed it, and nine did not clearly state
support or opposition.
The Service solicited formal scientific peer review of the proposal
from six professional biologists during the public comment period and
received comments from two reviewers. Their comments are either
incorporated into this listing decision as appropriate, or are
addressed below.
Written and oral comments presented at the public hearing and
received during the comment period were incorporated into this final
rule where appropriate. Comments not incorporated are addressed in the
following summary. Comments of a similar nature or point are grouped
and summarized. Where differing viewpoints around a similar issue were
made, the Service has briefly summarized the general issue.
Comment 1: Threats to the species are greatly exaggerated and
inconsistent with available data. No real or immediate threat exists
that would justify listing these invertebrates.
Service Response: The primary threat to these species is loss of
water in their habitat at Comal Springs and other springs where they
occur. This threat is discussed in detail in Factor A of this rule.
Comment 2: Samples of all three of the species were collected after
the springs had ceased flowing in the immediately preceding years.
Service Response: Spring flow did not cease from all outlets in
1990, and only spring run 1 at Comal saw significant loss of water.
During brief periods of very low spring flow the spring runs probably
retain sufficient subsurface moisture to allow the Comal springs riffle
beetle to survive. Furthermore, when periods of low spring flow are
brief and the spring runs are not completely dry, the subsurface water
level likely remains higher and closer to the spring openings. These
conditions may allow the survival of these species, whereas a period of
extensive, long-term cessation of spring flow likely would not. Because
these invertebrates are fully aquatic and require relatively well-
oxygenated water, a reduction or cessation of spring flows, even if
standing water remains around the spring orifices, may negatively
impact the species. Loss of water entirely, within their habitat, would
result in the extirpation of these aquatic species.
Comment 3: It was noted that the Edwards Aquifer Authority
(Authority) was created by S.B. 1477 to regulate withdrawal of water
from the aquifer. The Authority withstood legal challenges with the
passage of H.B. 3189, which was passed with the cooperation and
guidance of the Department of Justice and implementation is
anticipated. The commenter further stated that implementation of S.B.
1477 and H.B. 3189 will regulate water withdrawal,
[[Page 66298]]
thus eliminating the primary threat, and the need to list the species.
Service Response: Some of the legal issues regarding the
establishment of the Authority have been resolved since the time the
proposed rule was published and the elected board is in effect at this
time. However, an aquifer management plan that would provide for
protection of these species and their habitat is not yet in place.
Further progress of this board could be beneficial in the future and,
if threats are reduced or removed, could result in downlisting or,
possibly, delisting the species.
Comment 4: The City of New Braunfels has obtained surface water to
meet base demand which will eliminate pumping in the immediate area of
the springs and substantially diminish threats to the species.
Service Response: As discussed in Factor A, all of the springs
where these species occur are affected by water withdrawal throughout
the aquifer's artesian zone to the west. Therefore, a management plan
for the entire aquifer, not just the area near the springs, is
necessary to moderate threats to the species.
Comment 5: Service treatment of this complex and dynamic issue is
incomplete and erroneous. The Service ignores Texas Natural Resources
Conservation Commission (TNRCC) rules and proposed amendments to
address water quality.
Service Response: The Service acknowledges the extreme complexity
of issues regarding the quality and quantity of water in the Edwards
Aquifer. The TNRCC rules deal primarily with water quality issues. The
more significant issue, however, is maintaining adequate spring flows
and the likelihood that a water management plan will be in effect in
the foreseeable future that will provide protection for these
invertebrates, as discussed in Factor A.
Comment 6: If currently listed species are provided adequate spring
flow, then species that have survived previous cessation of spring flow
will receive adequate protection without the need to list.
Service Response: While there are species within the Comal and San
Marcos ecosystems that are presently listed as threatened or
endangered, none of these listed species are assured adequate spring
flow. Furthermore, some of the techniques, such as spring flow
augmentation, under consideration by some for providing spring flow,
will not adequately provide for the invertebrates addressed in this
final rule. For example, the Comal Springs riffle beetle occurs in the
spring runs. If water is ``augmented'' into this area after the springs
cease flowing, the spring orifices will act as recharge features. The
water would return to the aquifer rather than remaining in the spring
runs. In addition, if augmentation is attempted through subsurface
modifications of the aquifer, the habitat of the two subterranean
species could be negatively impacted.
Comment 7: In 1991, the Service reported that these invertebrates
were endemic to Comal Springs. Now each of the invertebrates is known
from one other spring and each is known from all of the upper springs
at Comal. This establishes a potentially wide range for the species.
The subterranean habits of two of the species and the fact that they
are found at springs as much as 20 miles apart suggests a much wider
distribution in the aquifer that would obviate the need to list them as
endangered.
Service Response: Status surveys that were conducted for each of
these species following the petition to list them found only one new
location for each species. Locations in more than one spring run at
Comal Springs is not surprising given the proximity of the spring runs.
As stated previously, extensive surveys for the species at springs
throughout Bexar, Comal, and Hays counties and examination of numerous
well samples have found each of the species at Comal Springs and in
very low numbers at one additional spring system each. The species were
not found at most of the locations surveyed.
Disjunct distributions (e.g., those that are separated by 20 miles)
are common in nature and can arise from many evolutionary and
ecological processes. Unfortunately, these species are not sufficiently
studied to allow us to give a precise explanation for the disjunct
distribution, or to determine with certainty whether it is disjunct.
Information in the Background section discusses the fact that specimens
of the subterranean species have not been found in well samples
throughout the aquifer area, in spite of extensive sampling. The
Service believes this is a good indication that the species are not
widely distributed underground. We do believe that efforts to collect
the species in any appropriate habitat where researchers were granted
access were sufficient to determine that, in all probability, the
species do not exist throughout the underground portions of the
aquifer.
Comment 8: Listing is not warranted until highly variable and
interruptible spring flow is considered as part of the historical cycle
to which these species are adapted to survive.
Service Response: These species exhibit no morphological
characteristics or behaviors indicating an ability to survive extended
drying of their habitat. The Comal Springs riffle beetle lacks the
ability to fly that many other riffle beetles have, suggesting that it
is adapted to continuous and reliable spring flows (although flow may
still be variable). The more frequent and severe drying that is
expected at current and increasing rates of withdrawal from the aquifer
will create a condition to which these species are not adapted to
survive.
Comment 9: As late as 1991, the Service made a warranted but
precluded finding for Peck's cave amphipod. The proposed listing gives
no explanation of the change in position from ``warranted but
precluded'' to ``proposed for listing.'' This is ironic since potential
threats to the species have been substantially addressed during this 4-
year period.
Service Response: A warranted but precluded finding means that the
best available information indicates that listing the species is
appropriate but that other pending listing actions are more urgently
needed and given a higher priority. Many of those other listing actions
have now been completed. Before publishing the proposed listing, the
Service reviewed the most current information available and determined
that the threats to the species are still significant. The Service
acknowledges and commends the efforts that so many individuals,
agencies, and organizations have put into looking for ways to manage
the Edwards Aquifer in a manner that will both protect the endemic
species and provide for human water users. However, significant aquifer
issues remain unresolved.
Comment 10: Spring flow may be irrelevant to the suitability of
habitat in the aquifer for the subterranean species.
Service Response: The Service recognizes that the Peck's cave
amphipod and the Comal Springs dryopid beetle are fully aquatic and
show morphological adaptations to a subterranean existence. However,
neither of these species has shown up in well samples and both have
only been collected near the spring orifices, a key feature of their
habitat is the water/spring orifice boundary. Reduced spring flows will
alter the position and the nature of this boundary and may have a
negative effect on these species. Further information is discussed in
the Background section.
Comment 11: The Service's failure to define a range or location of
habitat for these species is tantamount to an
[[Page 66299]]
admission that the Service does not know enough about the species to
warrant a conclusion that the species' habitat is threatened by
drought.
Service Response: The best available information indicates that the
range of each species is limited to a small area near each spring
opening where the species have been found. The range of each of the
species is both small in size and probably disjunct in distribution.
Further information on each species' habitat is presented in the
Background section.
Comment 12: Until more is known about the proposed species, and
some real harm is shown as a consequence of variable and interruptible
spring flows, they are not endangered species.
Service Response: The Service must make determinations for listing
of species based on ``the best scientific and commercial data
available'' at the time of listing. Existing knowledge indicates that
these species require a reliable supply of clean water. The species
have survived past dry periods, but models and predictions cited in the
proposal and in this final rule all agree that cessation of spring flow
is likely to be more frequent and of longer duration given present
pumping levels, as well as those outlined in S.B. 1477. Although S.B.
1477 limits total water withdrawal from the aquifer, the limits may
currently be too high to assure long-term spring flow. The Texas Water
Development Board (1992) models indicate that at the proposed pumping
limit of 450,000 acre-feet, and given recharge levels and patterns
similar to those that occurred from 1934 to 1990, Comal Springs could
spend 10 to 20 years below 100 cubic feet per second (cfs), and could
stop flowing entirely for several years at a time (Texas Water
Development Board, personal communication). Negative impacts to the
habitat in spring run 1 at Comal Springs, including drying, occur as
flows approach 100 cfs.
Comment 13: Studies show that dissolved oxygen is high even at the
lowest spring flows. Dissolved oxygen does not appear to be a
determinative factor in the decision whether to list the species.
Service Response: The primary factor threatening the long-term
survival of these species is availability of a sufficient quantity of
water to maintain essential characteristics of their habitat. Although
water quality, including the need for certain levels of dissolved
oxygen, may be an important factor in their survival, the magnitude of
the threat from total loss of water is viewed as the greater threat.
Comment 14: There is no economic advantage to protecting these
invertebrates, and putting the life of virtually unknown species ahead
of human welfare does not make sense.
Service Response: Like these invertebrates, humans depend on
reliable supplies of clean water, and thus protecting our water
resources is vital to protecting human health. While the Service cannot
consider the economic consequences of species listings when making
listing determinations, we believe that protecting these species will
have a positive effect to humans in that it will ensure the persistence
of the water resource for future generations and will maintain a
healthy ecosystem. In addition, continuing spring flow is economically
important both in the vicinity of the springs for water recreation
businesses and downstream as far as the Gulf of Mexico, where inflow of
fresh water into the bays and estuaries is vital to recreational and
commercial fisheries.
Summary of Factors Affecting the Species
After a thorough review and consideration of all information
available, the Service has determined that Peck's cave amphipod
(Stygobromus pecki), Comal Springs riffle beetle (Heterelmis
comalensis), and Comal Springs dryopid beetle (Stygoparnus comalensis)
should be classified as endangered species. Procedures found at section
4(a)(1) of the Act and regulations implementing the listing provisions
of the Act (50 CFR part 424) were followed. A species may be determined
to be endangered or threatened due to one or more of the five factors
described in section 4(a)(1). These factors and their application to
these three invertebrate species are as follows:
A. The Present or Threatened Destruction, Modification, or Curtailment
of Their Habitat or Range
The main threat to the habitat of these aquatic invertebrates is a
reduction or loss of water of adequate quantity and quality, due
primarily to human withdrawal of water from the San Antonio segment of
the Edwards (Balcones Fault Zone) Aquifer and other activities. Total
withdrawal from the San Antonio region of the Edwards Aquifer has been
increasing since at least 1934, when the total well discharge was
101,900 acre-feet (Edwards Underground Water District 1989). In 1989,
the total well discharge was the highest on record at slightly more
than 542,000 acre-feet (Longley 1991, Edwards Underground Water
District 1992a). Between 1989 and 1995, total well discharge has ranged
from 327,000 acre-feet in 1992 to 489,000 acre-feet in 1990 (U.S.
Geological Survey, San Antonio, 1996).
There is an integral connection between the water in the aquifer
west of the springs and the water serving as habitat for these species.
Water in the Edwards Aquifer flows from west to east or northeast and
withdrawal or contamination of water in the western part of the aquifer
can have a direct effect on the quantity and quality of water flowing
toward the springs and at the spring openings. Prior to wells being
drilled into the aquifer, almost all of the water entering the aquifer
eventually exited at springs (Guadalupe-Blanco River Authority 1988).
The Texas Water Commission (TWC) (1989) classified the San Antonio
segment of the Edwards Aquifer as a critical area in terms of its
potential for groundwater problems related to overdrafting. They also
ranked Bexar, Comal, and Hays counties among the top 23 counties in
Texas for number of active groundwater public supply systems. Human
population in the region is expected to increase (Technical Advisory
Panel 1990, Edwards Underground Water District 1993), which will result
in increased demand for water from the aquifer.
The Texas Water Development Board has applied its model (1992) of
the Edwards Aquifer to determine the maximum pumping level that would
allow Comal Springs to continue to flow, assuming historic recharge
(Technical Advisory Panel 1990). They found that during a drought
similar to that of the 1950's, the maximum pumpage that would allow
spring flow at Comal Springs is about 250,000 acre-feet per year. ``At
this pumping level, Comal Springs could be expected to maintain some
annual flow although they may flow on an intermittent basis during a
recurrence of the drought of record'' (Technical Advisory Panel 1990).
The Panel also stated that in the year 2000, if pumping continues to
grow at historical rates and a drought occurs, Comal Springs would go
dry for a number of years (Technical Advisory Panel 1990).
Wanakule (1990) states that ``the present problem facing the
Edwards Aquifer is the threat of overdrafting of the annual average
recharge rate.'' McKinney and Watkins (1993) evaluated the Texas Water
Development Board model and other models and concluded that, without
limiting withdrawal to about 200,000 acre-feet per year, Comal Springs
will likely go
[[Page 66300]]
dry for extended periods during even a minor drought. The recent
creation of the Authority may help to alleviate this threat to some
degree (see Factor D for further discussion).
The Texas Water Development Board model runs indicate that at the
proposed pumping limit of 450,000 acre-feet, and given recharge levels
and patterns similar to what occurred from 1934 to 1990, Comal Springs
could spend 10 to 20 years below 100 cfs, and could stop flowing
entirely for several years at a time (Texas Water Development Board,
personal communication, 1997). A model run with the same general
parameters but a withdrawal of 400,000 acre-feet shows the same pattern
with some increase in spring flow, but still extended periods with no
spring flow (Texas Water Development Board, personal communication,
1997).
In 1984 and 1990, some of the higher-elevation Comal Springs ceased
flowing and water levels in the index well (J-17) in San Antonio
dropped to within 3.7 meters (m) (12 feet (ft)) of the historic low of
186.7 m (612.5 ft) that occurred in 1956 (Wanakule 1990). During the
drought conditions in the summer of 1996, spring flows at Comal Springs
dropped to a low of 83 cfs. During the entire year of 1996, spring flow
stayed below 200 cfs for about 252 days and below 100 cfs, the
approximate flow at which spring run 1 stops flowing, for about 59
days. Because these invertebrates require relatively well-oxygenated
water, a reduction or cessation of spring flows, even if standing water
remains around the spring orifices, may negatively impact the species.
Complete loss of water would likely result in the extirpation of these
aquatic species.
In addition to a loss of water, a decrease in the water level in
the aquifer could lead to decreased water quality at the springs. The
Balcones Fault Zone--San Antonio Region is bounded on the south and
east by a ``bad water'' interface across which the groundwater quality
abruptly deteriorates to greater than 1000 mg/l total dissolved solids.
Crossing the bad water interface, groundwater goes from fresh to saline
or brackish. Lowered water levels resulting from groundwater pumpage
and/or decreased recharge may at some point result in deterioration of
water quality in the fresh water section of the aquifer through
movement of the bad water interface. The Comal and San Marcos Springs
are less than 305 and 62 m (1,000 and 200 ft), respectively, from the
bad water interface (TWC 1989, Edwards Underground Water District
1992b). Although the data are inconclusive at present, even a small
movement of the water may negatively impact the species.
Other possible effects of reduced spring flow exist. These include
changes in the chemical composition of the water in the aquifer and at
the springs, a decrease in current velocity and corresponding increase
in siltation, and an increase in temperature and temperature
fluctuations in the aquatic habitat (McKinney and Watkins 1993).
Another threat to the habitat of these species is the potential for
groundwater contamination. Pollutants of concern include, but are not
limited to, those associated with human sewage (particularly septic
tanks), leaking underground storage tanks, animal/feedlot waste,
agricultural chemicals (especially insecticides, herbicides, and
fertilizers) and urban runoff (including pesticides, fertilizers, and
detergents).
Pipeline, highway, and railway transportation of hydrocarbons and
other potentially harmful materials in the Edwards Aquifer recharge
zone and its watershed, with the attendant possibility of accidents,
present a particular risk to water quality in Comal and San Marcos
Springs. Comal and San Marcos Springs are both located in urbanized
areas. Hueco Springs is located alongside River Road, which is heavily
traveled for recreation on the Guadalupe River, and may be susceptible
to road runoff and spills related to traffic. Fern Bank Springs is in a
relatively remote, rural location and its principal vulnerability is
probably to contaminants associated with leaking septic tanks, animal/
feedlot wastes, and agricultural chemicals.
Of the counties containing portions of the San Antonio segment of
the Edwards Aquifer, the potential for acute, catastrophic
contamination of the aquifer is greatest in Bexar, Hays, and Comal
counties because of the greater level of urbanization compared to the
western counties. Although spill or contamination events that could
affect water quality do happen to the west of Bexar County, dilution
and the time required for the water to reach the springs may lessen the
threat from that area. As aquifer levels decrease, however, dilution of
contaminants moving through the aquifer may also decrease.
The TWC reported that in 1988 within the San Antonio segment of the
Edwards Aquifer, Bexar, Hays, and Comal counties had the greatest
number of land-based oil and chemical spills in central Texas that
affected surface and/or groundwater with 28, 6, and 4 spills,
respectively (TWC 1989). As of July, 1988, Bexar County had between 26
and 50 confirmed leaking underground storage tanks, Hays County had
between 6 and 10, and Comal County had between 2 and 5 (TWC 1989)
putting them among the top 5 counties in central Texas for confirmed
underground storage tank leaks. The TWC estimates that, on average,
every leaking underground storage tank will leak about 500 gallons per
year of contaminants before the leak is detected. These tanks are
considered one of the most significant sources of groundwater
contamination in the state (TWC 1989).
The TWC (1989), using the assessment tool DRASTIC (Aller, et al.
1987), classified aquifers statewide according to their pollution
potential. The Edwards Aquifer (Balcones Fault Zone--Austin and San
Antonio Regions) was ranked among the highest in pollution potential of
all major Texas aquifers. The project's objective was to identify areas
sensitive to groundwater pollution from a contaminated land surface
based on the hydrogeologic setting. The area of particular concern was
the Edwards Aquifer recharge zone and its watershed.
The TWC (1989) also reviewed and reported known and potential risks
to Texas aquifers, such as from sanitary landfills, hazardous waste
disposal facilities, industrial waste and sewage disposal wells,
commercial feedlots, and graveyards. They found the following: ``Based
on this statewide assessment of potential and actual ground-water
contaminants, waste disposal practices being employed and existing
regulations which are available for contamination detection and
mitigation, it was concluded that there are still conditions that exist
or practices being used that are cause for concern. For the most part,
the state presently has in place regulations that will effectively
reduce future pollution, however past practices may return to haunt
us.''
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
No threat from overutilization of this species is known at this
time.
C. Disease or Predation
While individuals of these three species may be preyed upon by
various predatory insects or fish, no information indicates that this
is a substantial threat.
D. The Inadequacy of Existing Regulatory Mechanisms
Invertebrates are not included on the Texas Parks and Wildlife
Department's (TPWD) list of threatened and endangered species and are
provided no protection by the State. The TPWD
[[Page 66301]]
regulations do not contain provisions for protecting habitat of any
listed species.
Traditionally, the State of Texas has had no authority to regulate
withdrawal of groundwater from an aquifer. After a lawsuit filed
against the Service by the Sierra Club (Sierra Club v. Babbitt,
formerly Sierra Club v. Lujan), the Texas State Legislature passed a
bill (S.B. 1477) authorizing the creation of the Authority and granted
the Authority the power to regulate groundwater withdrawal from the
Edwards Aquifer. The bill limits groundwater withdrawal from the
aquifer to 450,000 acre-feet per year initially, reducing it to 400,000
acre-feet per year by January 1, 2008. However, Texas Water Development
Board models indicate that, at these proposed withdrawal limits, the
upper-elevation spring runs at Comal Springs could go dry frequently
and for significant periods of time (as happened in 1996) and
significant negative impacts to the species could occur before
continuous minimum springflows are in place.
One goal of the bill is to provide continuous minimum spring flow,
as defined by Federal statute, at Comal and San Marcos Springs by the
year 2012. This minimum flow is to protect species that are designated
as threatened or endangered under Federal or State law, but does not
protect unlisted species. In addition, an evaluation of the Texas Water
Development Board models used to set these withdrawal limits shows that
flow at Comal Springs will drop below 100 cfs and will likely go dry
for extended periods in time of severe drought and probably during
minor droughts (McKinney and Watkins 1993, TWDB 1992). McKinney and
Watkins (1993) believe it is unlikely that spring flow in Comal Springs
of at least 100 cfs for 80 percent of the time, except during severe
drought, can be met with a pumping limit greater than 200,000 acre-feet
per year. In addition, when the flow drops to 96 cfs, spring run 1 at
Comal Springs has already dried substantially (Thornhill, deposition in
Sierra Club v. Lujan). Finally, efforts to maintain minimum spring flow
at Comal and San Marcos Springs would not necessarily be sufficient to
maintain flow at Hueco and Fern Bank Springs, which lie at higher
elevations.
E. Other Natural or Manmade Factors Affecting Their Continued Existence
The effect of natural droughts in south central Texas will increase
in severity due to the large increase in human groundwater withdrawals
(Wanakule 1990). These species' very limited habitat is likely to be
lost through drying or decreased volume of spring flow during minor or
severe drought.
At present, competition is not known to be a significant threat to
these species. However, two exotic snail species, Thiara granifera and
Thiara tuberculata, are common in the spring runs and, as grazers, may
compete for food. Another exotic species, the giant ramshorn snail
(Marisa cornuarietis), is present in two of the spring runs and may
colonize the other runs at low flow levels. Marisa can have a
tremendous impact on vegetation, that in turn may affect the habitat
for surface-dwelling grazers like the riffle beetle.
The Service has carefully assessed the best scientific and
commercial information available regarding the past, present, and
future threats faced by these species in making this final rule. Based
on this evaluation the preferred action is to list the Peck's cave
amphipod (Stygobromus pecki), Comal Springs riffle beetle (Heterelmis
comalensis), and Comal Springs dryopid beetle (Stygoparnus comalensis)
as endangered. Endangered status is determined appropriate for these
three invertebrates given that threats are significant and could result
in extinction of these species throughout all or a significant portion
of their range. The immediate nature of these threats precluded
determining these species to be threatened species.
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. The
Service finds that designation of critical habitat is not prudent for
Peck's cave amphipod, the Comal Springs riffle beetle, and the Comal
Springs dryopid beetle. 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.
Designation of critical habitat would provide no benefits to these
species beyond those provided by listing and the subsequent evaluation
of activities under section 7 of the Act. Section 7 prohibits Federal
agencies from jeopardizing the continued existence of listed species or
destroying or adversely modifying listed species' designated critical
habitat.
In the Service's section 7 regulations at 50 CFR part 402, the
definition of ``jeopardize the continued existence of '' includes ``to
reduce appreciably the likelihood of both the survival and recovery of
the listed species,'' and ``destruction or adverse modification'' is
defined as ``a direct or indirect alteration that appreciably
diminishes the value of critical habitat for both the survival and
recovery of a listed species.'' Both of these definitions refer to
actions that reduce the survival and recovery of a listed species. Any
action that would appreciably diminish the value, in quality or
quantity, of spring flows (habitat) on which the species depend would
also reduce appreciably the likelihood of survival and recovery of the
three species. Because these species are endemic to such highly
localized areas, actions that affect water quality and quantity at the
springs will be fully evaluated for their effects on the three species
through analysis of whether the actions would be likely to jeopardize
their continued existence. The analysis for possible jeopardy applied
to these species would therefore be identical to the analysis for
determining adverse modification or destruction of critical habitat.
Therefore, there is no distinction between jeopardy and adverse
modification for activities impacting the springs on which these
species depend.
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 encourages and results in public
awareness and conservation actions by Federal, State, and local
agencies, private
[[Page 66302]]
organizations, and individuals. The Act provides for cooperation with
the States and requires that recovery actions be carried out for all
species. The protection required of Federal agencies and the
prohibitions against taking and harm are discussed, in part, below.
Conservation and management of the Peck's cave amphipod, Comal
Springs riffle beetle, and Comal Springs dryopid beetle are likely to
involve protection and conservation of the Edwards Aquifer and spring
flow at Comal, Hueco, San Marcos, and Fern Bank Springs. It is also
anticipated that listing will encourage research on critical aspects of
the species' biology.
Section 7(a) of the Act, as amended, 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)(4) requires Federal agencies to confer
informally with the Service on any action that is likely to jeopardize
the continued existence of a proposed species. If a species is listed
subsequently, section 7(a)(2) requires Federal agencies to ensure that
activities they authorize, fund, or carry out are not likely to
jeopardize the continued existence of such species or to destroy or
adversely modify its critical habitat.
If a Federal action may affect a listed species or its critical
habitat, the responsible Federal agency must enter into formal
consultation with the Service. Federal actions that may require
consultation include projects that would affect the quality or quantity
of water within the San Antonio segment of the Edwards Aquifer or
otherwise significantly affect the outlets or water output of Comal
Springs in New Braunfels, Texas; San Marcos Springs in San Marcos,
Texas; Hueco Springs in Comal County, Texas; and Fern Bank Springs in
Hays County, Texas. Examples of these types of activities include
projects that would involve withdrawal of water from the aquifer;
permits for municipal wastewater discharge; agricultural irrigation;
use of pesticides and herbicides; Environmental Protection Agency
National Discharge Elimination System permits; section 18 exemptions
under the Federal Insecticide, Fungicide, and Rodenticide Act; Corps of
Engineers permits for stream crossings; and Department of Housing and
Urban Development projects.
The Act and implementing regulations found at 50 CFR 17.21 set
forth a series of general prohibitions and exceptions that apply to all
endangered wildlife. These prohibitions, in part, make it illegal for
any person subject to the jurisdiction of the United States to take
(includes 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 species under certain circumstances.
Regulations governing permits are at 50 CFR 17.22 and 17.23. Such
permits are available for scientific purposes, to enhance the
propagation or survival of the species, and/or for incidental take in
connection with otherwise lawful activities. It is anticipated that few
trade permits would ever be sought or issued because these species are
not known to be in trade.
It is the policy of the Service (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 listing on proposed and ongoing
activities within a species' range. The purpose of this guidance is not
only to identify activities that would or would not likely result in
take of individuals, but activities that in combination will ultimately
affect the long-term survival of these species. This guidance should
not be used to substitute for local efforts to develop and implement
comprehensive management programs.
The Service believes that, based on the best available information,
activities that could potentially harm these invertebrates and result
in ``take'' include, but are not limited to:
(1) Collecting or handling of the species;
(2) Activities that may result in destruction or alteration of the
species' habitat including, but not limited to, withdrawal of water
from the aquifer to the point at which habitat becomes unsuitable for
the species, alteration of the physical habitat within the spring runs,
or physical alteration of the spring orifices or of the subsurface
pathways providing water to the springs;
(3) Discharge or dumping of chemicals, silt, pollutants, household
or industrial waste, or other material into the springs or into areas
that provide access to the aquifer and where such discharge or dumping
could affect water quality;
(4) Herbicide, pesticide, or fertilizer application in or near the
springs containing the species; and
(5) Introduction of non-native species (fish, plants, other) into
these spring ecosystems.
The Service believes that a wide variety of activities would not
harm these species if undertaken in the vicinity of their habitats and
thus would not constitute taking. In general, any activity in the
contributing, recharge, or artesian zones of the Edwards aquifer that
would not have potential for the cumulative or acute/catastrophic
negative effects on water quantity or quality within the aquifer should
not harm these species. Inquiries concerning the possible effects of
specific activities, copies of regulations regarding listed wildlife,
or inquiries regarding prohibitions and permits should be directed to
the Service's Austin Field Office (see ADDRESSES section).
National Environmental Policy Act
The Fish and Wildlife 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 Endangered Species Act of 1973, as amended. A notice
outlining the Service's reasons for this determination was published in
the Federal Register on October 25, 1983 (48 FR 49244).
Required Determinations
The Service has examined this regulation under the Paperwork
Reduction Act of 1995 and found it to contain no information collection
requirements.
References Cited
Aller, L., T. Bennett, J.H. Lehr, R.J. Petty, and G. Hackett. 1987.
DRASTIC: a standardized system for evaluating groundwater pollution
potential using hydrogeologic settings. U.S. Environmental
Protection Agency. EPA/600/2-87/035. 622 pp.
Arsuffi, Thomas L. 1993. Status of the Comal Springs Riffle Beetle
(Heterelmis comalensis Bosse, Tuff, and Brown), Peck's Cave Amphipod
(Stygobromus pecki Holsinger), and the Comal Springs Dryopid Beetle
(Stygoparnus comalensis Barr and Spangler). Prepared for the U.S.
Fish and Wildlife Service. 25 pp.
[[Page 66303]]
Barr, C.B. 1993. Survey for two Edwards Aquifer invertebrates: Comal
Springs dryopid beetle Stygoparnus comalensis Barr and Spangler
(Coleoptera: Dryopidae) and Peck's cave amphipod Stygobromus pecki
Holsinger (Amphipoda: Crangonyctidae). Prepared for U.S. Fish and
Wildlife Service. 70 pp.
Barr, C.B., and P.J. Spangler. 1992. A new genus and species of
stygobiontic dryopid beetle, Stygoparnus comalensis (Coleoptera:
Dryopidae), from Comal Springs, Texas. Proc. Biol. Soc. Wash.
105(1):40-54.
Bosse, L.S., D.W. Tuff, and H.P. Brown. 1988. A new species of
Heterelmis from Texas (Coleoptera: Elmidae). Southwestern Naturalist
33(2):199-203.
Brown, H.P. 1987. Biology of Riffle Beetles. Annual Review of
Entomology. 32:253-73
Brown, H.P., and C.B. Barr. 1988. First report of stygobiontic
(subterranean) riffle beetles in North America. Program abstract for
April 22, 1988, meeting of Southwestern Association of Naturalists.
5 pp.
Brune, G. 1981. Springs of Texas, Volume 1. Branch-Smith Inc., Ft.
Worth, Texas.
Chapman, R.F., 1982. The Insects: Structure and Function. Harvard
University Press, Cambridge, MA. 919 pp.
Edwards Underground Water District. 1989. Compilation of hydrologic
data for the Edwards Aquifer, San Antonio area, Texas, 1988, with
1934-88 summary: Bulletin 48, 157 pp.
Edwards Underground Water District. 1992a. Report of the technical
data review panel on the water resources of the south central Texas
region. 307 pp.
Edwards Underground Water District. 1992b. Investigation of the
fresh/saline water interface in the Edwards Aquifer in New Braunfels
and San Marcos, Texas. Report 92-02. 18 pp.
Edwards Underground Water District. 1993. Urban Development on the
Edwards Aquifer Recharge Zone. Report 93-09. 40 pp.
Guadalupe-Blanco River Authority. 1988. The Edwards Aquifer:
Underground River of Texas. Guadalupe-Blanco River Authority,
Seguin, Texas. 63 pp.
Holsinger, J.R. 1967. Systematics, speciation, and distribution of
the subterranean amphipod genus Stygonectes (Gammaridae). Bull. U.S.
Nat. Mus. 259:1-176.
Longley, G. 1991. Status and trends of the Edwards (Balcones Fault
Zone) Aquifer in the San Antonio Region. pp. 4-18 In: Proceedings of
South Texas Irrigation Conference. Guy Fipps, ed. 146 pp.
McKinney, D.C., and D.W. Watkins, Jr. 1993. Management of the
Edwards Aquifer: A critical assessment. Technical Report CRWR 244.
Center for Research in Water Resources, Bureau of Engineering
Research. University of Texas at Austin. 94 pp.
Technical Advisory Panel. 1990. Technical factors in Edwards Aquifer
use and management. Prepared for Special Committee on the Edwards
Aquifer. 57 pp.
Texas Department of Water Resources. 1979. Geohydrology of Comal,
San Marcos, and Hueco Springs. Report 234. Prepared by Guyton ans
Associates. 85 pp.
Texas Water Commission. 1989. Ground-water quality of Texas-an
overview of natural and man-affected conditions. Austin, Texas. 197
pp. and 3 plates.
Texas Water Development Board. 1992. Model Refinement and
Applications for the Edwards (Balcones Fault Zone) Aquifer for the
San Antonio Region, Texas. Texas Water Development Board. Report
340. July 1992. 33 pp.
U.S. Geological Survey. 1996. Unpublished summary tables on Edwards
Aquifer discharge. U.S. Geological Survey, San Antonio. 3 pp.
Wanakule, N. 1990. Stochastic drought analysis of the Edwards
Aquifer. Edwards Aquifer Research and Data Center No. R1.-90, San
Marcos, Texas. 32 pp.
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, and Transportation.
Regulation Promulgation
Accordingly, part 17, subchapter B of chapter I, title 50 of the
Code of Federal Regulations, the Service amends as follows:
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 and Insects, respectively, to the
List of Endangered and Threatened Wildlife to read as follows:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species
-------------------------------------------------------- Historic range Family Status When listed Critical Special
Scientific name Common name habitat rules
--------------------------------------------------------------------------------------------------------------------------------------------------------
Crustaceans
* * * * * * *
Stygobromus (=Stygonectes) pecki. Amphipod, Peck's U.S.A. (TX)........ Crangonyctidae..... E ........... NA NA
cave.
* * * * * * *
Insects
* * * * * * *
Stygoparnus comalensis........... Beetle, Comal U.S.A. (TX)........ Dryopidae.......... E ........... NA NA
Springs dryopid.
* * * * * * *
Heterelmis comalensis............ Beetle, Comal U.S.A. (TX)........ Elmidae............ E ........... NA NA
Springs riffle.
* * * * * * *
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[[Page 66304]]
Dated: October 21, 1997.
Jamie Rappaport Clark,
Director, Fish and Wildlife Service.
[FR Doc. 97-33041 Filed 12-17-97; 8:45 am]
BILLING CODE 4310-55-P