Endangered and Threatened Wildlife and Plants; Final Rule To List Three Aquatic Invertebrates in Comal and Hays Counties, TX, as Endangered

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.

* * * * * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------

[[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