[Federal Register: December 27, 2001 (Volume 66, Number 248)]
[Rules and Regulations]               
[Page 66803-66811]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]



Fish and Wildlife Service

50 CFR Part 17

RIN: 1018-AI19

Endangered and Threatened Wildlife and Plants; Listing the 
Tumbling Creek Cavesnail as Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Emergency rule.


SUMMARY: We, the Fish and Wildlife Service (Service), exercise our 
authority to emergency list the Tumbling Creek cavesnail (Antrobia 
culveri) as endangered under the Endangered Species Act of 1973, as 
amended (Act). This species is known to occur in one cave in Missouri. 
The distribution of this species has decreased in Tumbling Creek by 90 
percent since 1974. Although cavesnail numbers fluctuated seasonally 
and annually between 1996 and 2000, the species was not found in the 
monitored section of the cave stream during five surveys in 2001. 
Because the sudden population decline demonstrates a significant and 
imminent risk to the well-being of the Tumbling Creek cavesnail, we 
find that emergency listing is necessary to provide Federal protection 
pursuant to the Act for 240 days. A proposed rule to list the Tumbling 
Creek cavesnail as endangered is published concurrently with this 
emergency rule, and can be found in this issue of the Federal Register 
in the proposed rules section.

DATES: This emergency rule becomes effective December 27, 2001 and 
expires August 26, 2002.

ADDRESSES: The complete file for this rule is available for inspection, 
by appointment, during normal business hours at the U.S. Fish and 
Wildlife Service, Columbia, Missouri Field Office, 608 E. Cherry St., 
Room 200, Columbia, Missouri 65201-7712.

Missouri Field Office, at the address listed above (telephone: 573-876-
1911, ext. 107; e-mail: paul__mckenzie@fws.gov; facsimile: 573-876-
1914). Individuals who are hearing-impaired or speech-impaired may call 
the Federal Relay Service at 1-800-877-8337 for TTY assistance.



    The Tumbling Creek cavesnail (Antrobia culveri) was described as a 
new species by Hubricht (1971) from specimens taken by David Culver, 
Thomas Aley, and Leslie Hubricht in 1969 and 1970. Antrobia culveri is 
the type species for the genus Antrobia, also described new to science 
in 1971 by Hubricht. Hershler and Hubricht (1988) examined specimens of 
Antrobia culveri and confirmed the taxonomic placement of this species 
in the subfamily Littoridininae of the Gastropod family Hydrobiidae. 
They also noted the apparent close relatedness of the genus Antrobia to 
the genus Fontigens, which contains cave-adapted snails found in other 
Missouri caves and springs. The Tumbling Creek cavesnail is a small, 
white, blind, aquatic snail (height 2.3 millimeters (mm) (0.09 inches 
(in); diameter 2.0 mm (0.08 in); aperture height 1.2 mm (0.05 in); 
aperture diameter 1.1 mm (0.04 in)) with a small, conical, well-
rounded, pale-yellow shell containing about 3.5 whorls (Hubricht 1971). 
The Tumbling Creek cavesnail is restricted to a single cave stream in 
Tumbling Creek Cave in Taney County, southwestern Missouri.
    Greenlee (1974) provided the first information on the habitat of 
the species. He reported that the species was found primarily on ``3 
inch gravel substrate'' (presumably meaning small stones or cobble of 
3-inch diameter), with a few individuals observed using the recesses of 
a solid rock stream bottom. Greenlee (1974) did not note whether the 
snails used the upper or lower surface of the 3-inch gravel he observed 
them on, or whether the species was ever observed using larger rocks 
within the cave stream. Subsequent surveyors, however, have failed to 
document Antrobia culveri using a solid rock bottom, and the species is 
usually observed on the undersurface of rocks with a diameter greater 
than 3 inches (Ashley 2000). Additionally, Greenlee (1974) stated that 
the Tumbling Creek cavesnail was absent from areas of the stream that 
contained bat guano. Subsequent observers (McKenzie in litt. 1996; 
Ashley 2000, 2001a, 2001b) have noted Antrobia culveri in portions of 
Tumbling Creek where bat guano occurs. Finally, Greenlee (1974) and 
subsequent observers have all noted that the species appears to prefer 
areas of the stream that lack silt.

[[Page 66804]]

    Although little is known regarding the life history of this 
cavesnail, Greenlee (1974) postulated that the species feeds on aquatic 
microfauna. Because Tumbling Creek cavesnails have been concentrated in 
sections of Tumbling Creek Cave that are usually adjacent to large 
deposits of bat guano, it has been theorized that Antrobia culveri is 
indirectly dependent upon these deposits for food (Greenlee 1974). 
Other life history aspects of this species, including its reproductive 
behavior, are unknown. Although little is known about the longevity or 
movements of this species, some limited information is available on the 
frequency of shell sizes within the population across different 
seasons. Ashley (2000) examined shell length data collected between 
1996 and 2000 and noted that the average length of Antrobia culveri 
shells exhibited a slight peak during summer months but further noted 
that the difference was not statistically significant. Ashley (2000) 
also analyzed the frequency distribution of cavesnail shell lengths 
from fall data collected between 1997 and 2000 and noted a decrease in 
the frequency of smaller shells over that period. Ashley (2000) 
concluded that both fewer snails and fewer snails in the younger age 
classes were observed in the more recent fall visits conducted from 
1997 through 2000. This suggests that there has been a reduction in 
recruitment of younger age classes into the population between 1997 and 
    Tumbling Creek Cave is a highly diverse cave (Thomas Aley, Ozark 
Underground Laboratory (OUL), in litt. 1978; Cecil Andrus, USDI, in 
litt. 1980). In addition to species included in the Missouri Department 
of Conservation's (MDC) Checklist of Species of Conservation Concern 
(Missouri Natural Heritage Program 2001) (e.g., a cave millipede 
(Scoterpes dendropus)), Antrobia culveri is associated with at least 
three, possibly six, species that are new to science but have not yet 
been formally described: a millipede (Chaetaspis sp.), a terrestrial 
isopod (Caucasonethes sp.), an amphipod (Stygobromus sp.), a dipluran 
(Plusiocampa sp.), a phalangodid harvestman (Phalangium sp.), and a 
cave spider (Islandiana sp.). Tumbling Creek Cave also provides habitat 
for a large maternity colony of federally listed gray bats (Myotis 
grisescens), with a recent estimated breeding population of 12,400 in 
1998 (Dr. William Elliott, MDC, in litt. October 9, 2001). 
Historically, the breeding population included an estimated 50,000 
individuals (MDC 1992, Missouri Natural Heritage Program 2000). There 
have also been historical observations of a very small hibernating 
population of the federally listed Indiana bat (Myotis sodalis). 
However, the Indiana bat has not been documented at the site since 1989 
(Missouri Natural Heritage Program 2000). The Gray Bat Recovery Plan 
lists Tumbling Creek Cave as a ``Priority 1'' cave. Priority 1 gray bat 
caves have the highest level of biological significance for a gray bat 
maternity site (i.e., a cave deemed to be ``absolutely essential'' in 
preventing the extinction of the endangered gray bat) (U.S. Fish and 
Wildlife Service 1982).
    Tumbling Creek Cave is owned by Tom and Cathy Aley of Protem, 
Missouri. Because of its rich cave fauna, the large maternity colony 
for the endangered gray bat, and its diverse physical features, 
Tumbling Creek Cave was designated as a National Natural Landmark and 
approved for inclusion on the National Registry of Natural Landmarks 
under the authority of the Historic Sites Act of 1935 (49 Stat. 666; 16 
U.S.C. 461 et seq.) (Cecil Andrus, USDI, in litt., 1980; 48 FR 8693). 
Tumbling Creek Cave and approximately 395 acres surrounding the cave 
were embodied in the designation, including about 140 surface acres 
owned by the Aleys and about 255 surface acres owned by two adjacent 
property owners.

Status and Distribution

    Antrobia culveri is known only from Tumbling Creek Cave in Taney 
County, southwestern Missouri. In an extensive survey of publicly and 
privately owned Missouri caves, no additional populations of this 
cavesnail were discovered (Gardner 1986). Recent surveys conducted in 
nearby caves and springs by Dr. David Ashley of Missouri Western State 
College, St. Joseph, Missouri, have also failed to locate this species 
at any other sites (David Ashley, in litt. November 2001). The fact 
that no additional populations were found in springs in close proximity 
to Tumbling Creek Cave supports the long-held contention that Tumbling 
Creek cave is the only location where this species occurs.
    Antrobia culveri was historically known from an estimated area of 
1,016 square meters (m\2\) (10,900 square feet (ft\2\) or 0.25 acres) 
(Greenlee 1974) of Tumbling Creek along approximately 229 meters (m) 
(750 feet (ft)) of the stream in the approximate middle one-third of 
the lower stream passage in Tumbling Creek Cave (Greenlee 1974). Based 
on a survey of approximately 630 m\2\ (6,800 ft\2\) of suitable habitat 
within the 457 m (1,500 ft) of human-accessible cave-stream habitat, 
Greenlee (1974) estimated the population of Tumbling Creek cavesnails 
at 15,118 individuals.
    In 1995, we reviewed the status of the species, including the 
survey methodology originally established by Greenlee (1974), and 
determined that an inadequate description of the survey methods made it 
difficult to determine the number of plots taken. Our lack of knowledge 
on the number of plots sampled by Greenlee made it difficult to 
interpret his population estimates and impossible to duplicate his 
survey methods. Therefore, we concluded that a more rigorous 
statistical survey design would be necessary to establish population 
trends for the species. Following meetings with Dr. Pam Haverland of 
the U.S. Geological Survey, Columbia Environmental Research Center in 
Columbia, Missouri, and Mr. Tom Aley, President of Ozark Underground 
Laboratory (OUL) and owner of Tumbling Creek Cave, a sampling protocol 
was established within an approximate 75 m (247 ft) section of Tumbling 
Creek that was known to be inhabited by Antrobia culveri but that would 
minimize any potential impacts to the federally endangered gray and 
Indiana bats.
    Following the establishment of sampling stations within Tumbling 
Creek Cave, and an initial September 1996 survey using those stations 
(McKenzie, in litt. 1996), we contracted Dr. David Ashley, of Missouri 
Western State College, St. Joseph, Missouri, to monitor population 
trends of the Tumbling Creek cavesnail. Ashley completed 16 separate 
monitoring trips between September 3, 1997, and August 31, 2001 (Ashley 
2000, 2001a, 2001b, 2001c). Ashley (2000, 2001a, 2001b, 2001c) 
determined that population estimates of Antrobia culveri within the 
monitoring stations fluctuated both seasonally and annually, and ranged 
from a high of 1,166 individuals on September 3, 1997, to a low of 0 
individuals on January 11, March 17, May 8, July 16, and August 31, 
2001. Ashley statistically analyzed the data and concluded that a 
significant decrease in the numbers of cavesnails had occurred between 
September 9, 1996, and August 31, 2001 (Ashley 2001c).
    Although the 2001 surveys failed to document the presence of any 
cavesnails within the established monitoring stations, 40 individuals 
were discovered upstream of the sampling stations in March 2001. During 
March 16-18, 2001, Ashley and others surveyed the entire human-
accessible 457 m (1,500 ft) of Tumbling Creek, including a small 
tributary that has approximately 9 additional meters (30

[[Page 66805]]

ft) of accessible habitat. A total of 39 person-hours was expended in 
searching a total of 1,054 rocks in the 466 m (1,530 ft) of available 
habitat. A total of 39 cavesnails were located in a 14-m (45-ft) 
section of the stream upstream from the monitoring stations, and 
another cavesnail was found in the tributary (Ashley 2001a). Subsequent 
surveys in May, July, and August 2001 documented the presence of 
cavesnails only in this 14-m section upstream of the established 
sampling stations. The small tributary stream was not searched during 
those subsequent surveys. A more thorough search was not conducted in 
either the tributary or the area upstream from the sampling stations in 
order to minimize disturbance to cavesnails in those areas. 
Observations between March and August 2001 suggest that the numbers of 
Antrobia culveri have declined drastically from estimates obtained by 
Greenlee (1974); however, differing sampling methods make it impossible 
to directly compare Ashley's estimates with those of Greenlee.
    In addition to Greenlee's 1974 survey and the standardized surveys 
conducted between 1996 and 2001, other attempts have been made to 
monitor the species' status and derive estimates of its abundance. A 
June 1991 survey conducted by Tom Aley, Paul McKenzie (Service, 
Columbia, Missouri), and Dennis Figg (MDC, Jefferson City, Missouri) 
located 42 individuals after a 9 person-hour search (McKenzie, pers. 
obs.). A June 1993 survey conducted by Monty Holder (a high school 
biology instructor) of Sedalia, Missouri, and three assistants located 
21 individuals during 6 person-hours of search effort (Tom Aley, in 
litt. 1993), but the number of plots sampled is unknown. On August 29, 
1995, Paul McKenzie and Cathy Aley searched for the species and 
attempted to estimate the number of cavesnails discovered per 0.3048 
m\2\ (1 ft\2\) plot. This survey yielded 6 cavesnails in 22 plots or 
0.27 cavesnails per plot (McKenzie, unpubl. data). This compares to an 
estimated 2.16 cavesnails per plot observed by Greenlee (1974) when 
equivalent plot sizes were calculated for analysis purposes. Although 
it is impossible to determine the exact number of plots sampled by 
Greenlee (1974), he did record the average number of snails per plot, 
and this can be compared to the same variable measured in 1995. A 
decrease from 2.16 cavesnails per plot to 0.27 cavesnails per plot 
would represent an approximate 88 percent decrease in the species' 
density over the 22-year period between 1974 and 1995.

Previous Federal Action

    On January 6, 1989, the Service published an Animal Notice of 
Review (54 FR 54554-54579) which included the Tumbling Creek cavesnail 
as a category 2 candidate species for possible future listing as 
threatened or endangered. Category 2 candidates were those taxa for 
which information contained in the Service's files indicated that 
listing may be appropriate but for which additional data were needed to 
support a listing proposal. On November 21, 1991, the Service published 
an Animal Candidate Notice of Review (56 FR 58804-58836), which 
elevated the Tumbling Creek cavesnail to category 1 status. Category 1 
candidates were those taxa for which the Service had on file sufficient 
information on biological vulnerability and threats to support 
preparation of listing proposals. In the subsequent February 28, 1996, 
Candidate Notice of Review (61 FR 7596-7613), we indicated that the 
category 2 candidate species list was being discontinued, and that 
henceforth the term ``candidate species'' would be applied only to 
those taxa that would have earlier fit the definition of the former 
category 1 candidate taxa, that is, those species for which we had on 
hand sufficient information to support a listing proposal. The Tumbling 
Creek cavesnail has remained a candidate species until now.
    In 1996, we initiated a 5-year set of standardized surveys designed 
to better assess and quantify the decline in the species' population 
that was apparent from the earlier data. In January 2001, Ashley (pers. 
comm. January 14, 2001) notified the Service that no cavesnails were 
observed within the established monitoring stations during the January 
11 survey. He further reported that an analysis of 5 years of data 
collected between September 1996 and March 2001 indicated that 
population numbers of the species had exhibited an alarming decline 
(Ashley 2001b). Based on this information, the Service determined that 
it was necessary to more closely monitor the species by having surveys 
conducted once every two months.
    Recognizing the need for prompt additional conservation actions for 
the species, on January 30, 2001, Region 3 of the Service recommended 
changing the listing priority number for the Tumbling Creek cavesnail 
from 7 to 1 based upon the mid-January monitoring that failed to locate 
any cavesnails (Service 2001). Region 3 also recommended pursuing an 
emergency listing of the species and simultaneously publishing a 
proposal for long-term listing as endangered under the Act as soon as 
funding became available. On October 30, 2001, we published an updated 
Candidate Species Notice of Review (66 FR 54808) that formally changed 
the listing priority number for Antrobia culveri from 7 to 1, 
reflecting our increased concern for the survival of the species.
    On August 29, 2001, the U.S. Department of the Interior reached an 
agreement with several conservation organizations regarding a number of 
listing actions that had been delayed by court-ordered critical habitat 
designations and listing actions for other species. That agreement was 
subsequently approved by the U.S. District Court for the District of 
Columbia. Under the agreement, the Service and the organizations agreed 
to significantly extend the existing court-approved deadlines for the 
actions on the other species, thereby making funds available for a 
number of listing actions judged to be higher priority by the Service. 
Those higher priority listing actions include the emergency listing of 
the Tumbling Creek cavesnail.

Summary of Factors Affecting the Species

    After a thorough review and consideration of all information 
available, the Service has determined that the Tumbling Creek cavesnail 
warrants classification as an endangered species. We followed 
procedures found in section 4 of the Act (16 U.S.C. 1533) and 
regulations (50 CFR part 424) promulgated to implement the listing 
provisions of the Act. We may determine a species to be endangered or 
threatened due to one or more of the five factors described in section 
4(a)(1) of the Act. These factors and their application to the Tumbling 
Creek cavesnail (Antrobia culveri) are as follows:

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

    Antrobia culveri has exhibited a drastic decline in numbers since 
the first estimate was made by Greenlee (1974) (see Status and 
Distribution, above). Systematic sampling conducted at established 
stations between 1996 and 2001 revealed that a statistically 
significant decline in population has occurred over that period 
(McKenzie in litt. 1996; Ashley 2000, 2001a, 2001b, 2001c). 
Additionally, no cavesnails have been located at established monitoring 
stations during the last five surveys (Ashley 2001a, 2001b, 2001c).
    We have also documented a dramatic reduction in the portion of the 

[[Page 66806]]

stream occupied by the cavesnail. Antrobia culveri was historically 
known from an estimated 229 m (750 ft) of Tumbling Creek (Greenlee 
1974). The 229 m of occupied habitat in 1974 constituted 50 percent of 
the 457 m (1,500 ft) of human-accessible cave-stream habitat that is 
believed to be suitable for the cavesnail. The entire accessible 457 m 
(1,500 ft) of Tumbling Creek, including a small tributary that has 
approximately 9 additional meters (30 ft) of accessible suitable 
habitat, was surveyed in March 2001. Cavesnails were found solely in 
one small (14-m) (45-ft) section of the stream and in the small 
tributary (Ashley 2001a). Observations between March and August 2001 
suggest that Antrobia culveri is now restricted to 23 m of available 
stream habitat or approximately 5 percent of the 457 m of accessible 
suitable habitat. These figures indicate that distribution of this 
species in Tumbling Creek Cave has decreased by 90 percent.
    Species such as the Tumbling Creek cavesnail, which spend part or 
all of their life cycle in subterranean water systems, are highly 
vulnerable to changes in the quality and quantity of that water. In 
turn, the quality and quantity of the subsurface water is highly 
dependent upon conditions and human activities on the land surface from 
which water feeds into losing streams and sinkholes that drain into 
underground karst conduits. Surface water moves into the subsurface 
system by a number of mechanisms, including sinkholes, percolation 
through sandy or gravelly soils and stream bottoms, and seepage and 
flowage into crevices. As water moves from the surface to the 
subsurface system, it carries the chemicals and particulate matter from 
the surface. The land surface that feeds water into a particular cave 
stream is referred to as the ``recharge area'' for that cave stream. 
Because recharge areas may be large and may consist of all or parts of 
several surface watersheds, it is critically important to accurately 
determine the boundaries of the recharge area with reliable 
hydrogeological methods. Only when the recharge area is accurately 
delineated can water quality threats be successfully addressed (Aley 
and Aley 1991).
    The recharge area that feeds water into Tumbling Creek Cave has 
been recently delineated by the cave owner, Mr. Thomas Aley of the OUL, 
who is also a recognized cave specialist and expert karst 
hydrogeologist (Aley and Aley 2001). Pending the results of additional 
recharge delineation studies currently being conducted by Aley on a 
tract of land recently purchased by him and Cathy Aley (Tom Aley, pers. 
comm., September 24, 2001), he estimated the recharge area to be 
approximately 2,349 hectares (5,804 acres or 9.07 square miles). Land 
ownership based on current data within the recharge area is: (1) Tom 
and Cathy Aley own approximately 1,550 acres, or 25 percent of the 
total; (2) employees of Ozark Underground Laboratory and other private 
individuals who manage their property to protect water quality and 
benefit the species own approximately 1,268 acres or 22 percent; (3) an 
estimated 1,300 acres or 23 percent is within Mark Twain National 
Forest; (4) the U.S. Army Corps of Engineers (CE) owns an estimated 100 
acres or 2 percent; and (5) other private landowners whose land use 
practices and knowledge of the cavesnail are currently unknown to us 
own approximately 1,636 acres or 28 percent. Thus, within the 
delineated recharge area for Tumbling Creek Cave, roughly 4,168 acres 
or approximately 72 percent is either in public or private ownership by 
entities who can be expected to manage their land to benefit the 
species. This includes 920 acres recently purchased by Tom and Cathy 
Aley, or about 22 percent of the total conservation ownership. However, 
most of this recently purchased land was subject to recent land use 
practices (e.g., over-grazing and removal of riparian vegetation) that 
resulted in heavy soil erosion that probably continues to contribute to 
deteriorating water quality in Tumbling Creek Cave. Remediation and 
restoration of these lands are planned and will require considerable 
funds, effort, and time.
    The Tumbling Creek cavesnail is likely threatened by habitat 
degradation through diminished water quality from upstream locations 
within the unprotected or improperly managed areas within the cave's 
delineated recharge zone. The dramatic decrease in the population and 
area occupied by this species is probably attributable to degraded 
water quality from these sources. In recent years, there has been a 
noticeable increase in water turbidity in Tumbling Creek; the increased 
turbidity has probably had an adverse effect on the water quality in 
the cave's stream (Tom and Cathy Aley, pers. comm., August 30, 2001). 
Increased silt loads within Tumbling Creek could adversely affect the 
cavesnail by hampering reproduction and recruitment by suffocating 
juvenile cavesnails (Ashley 2000). Tom and Cathy Aley have also 
observed that clay particles within deposited silt have settled between 
gravel and rocks and cemented them together and to the stream bottom 
(Tom and Cathy Aley, pers. comm., August 2001). Such cementing 
decreases habitat available to cavesnails, because they are generally 
restricted to the undersurface of gravel and rocks. This hypothesis is 
supported, in part, by the observations of Greenlee (1974), who 
reported that cavesnails occurred primarily on ``3 inch gravel 
substrate'' rather than on the larger rocks the species has been seen 
using during more recent surveys. Interestingly, Ashley's (2000) 
results revealed that some older individuals use silt-covered 
substrates. This is different from the observations made by Greenlee 
(1974) who noted that cavesnails were not observed in areas of the 
stream where fine silt was deposited. Ashley's observations may be 
because of a reduction in the amount of silt-free substrates preferred 
by cavesnails which could force the species to use less favorable 
habitats. Although silt has been a component of Tumbling Creek since 
Greenlee's initial survey in 1974, it has apparently increased 
significantly since that date (Tom and Cathy Aley, pers. comm., August 
2001). Additional research is needed to determine the degree of silt 
deposition within Tumbling Creek and if the deposition of silt into the 
cave is adversely impacting the species, especially smaller and younger 
individuals (Ashley 2000).
    Potential sources of silt within the cave's recharge area have been 
identified on the two tracts recently purchased by Tom and Cathy Aley, 
including an earthen dam that burst, and severely degraded and eroded 
pastureland due to overgrazing. In the latter case, soil erosion has 
been exacerbated in the last six years by the removal of nearly all 
vegetation within the riparian corridors of all semi-permanent and 
intermittent streams on one of those parcels. Harvey (1980) concluded 
that ``accelerated erosion and sediment transport'' was a problem 
within drainage basins that have ``excessive slopes,'' and identified 
``timber cutting and land clearing for raising livestock, extending 
urban sprawl, and highway building'' as potential sources of 
``accelerated erosion.'' In addition to these sources, the construction 
of fire lanes associated with controlled burning on Forest Service 
property within the recharge area may increase the threat of soil 
erosion with a resulting decrease in water quality in Tumbling Creek.
    Other factors within the recharge area of Tumbling Creek Cave that 
could contribute to the deterioration of the water quality of Tumbling 

[[Page 66807]]

include: (1) increase in ammonia and nitrate loads from livestock 
feedlots that could lead to reductions in dissolved oxygen levels, (2) 
chemicals used for highway maintenance or from accidental spills, and 
(3) contaminants from different types of trash or hazardous waste 
materials deposited into sinkholes, ravines, and depressions. Whether 
these factors are occurring on the parts of the recharge area that are 
outside of the current ``conservation ownership'' remains to be 
determined. Refer to Factor E for a discussion of these potential 

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

    Because access to Tumbling Creek Cave is controlled by the cave 
owners, all collection of and research on Antrobia culveri is strictly 
controlled. Consequently, there is no evidence of overutilization of 
this species for commercial, recreational, scientific, or educational 
purposes. There is also no evidence that disturbance associated with 
conducting regular surveys is adversely affecting the species. Rocks 
that are examined are carefully replaced in the location from which 
they were removed, any specimens discovered are disturbed as little as 
possible and kept moist to reduce stress, and only a small percentage 
of the available habitat is sampled during each survey.

C. Disease or Predation

    The direct effect of disease on the Tumbling Creek cavesnail is not 
known and such risks to the species have not been determined. Because 
the Tumbling Creek cavesnail is known from a single location, disease 
must be considered a potential threat to the survival of the species. 
Certain species of salamanders have been shown to be adversely impacted 
by the bacterium Acinetobacter that flourished due to increasing levels 
of nitrogen associated with the overstocking of livestock (Worthylake 
and Hovingh 1989). Similarly, Lefcort et al. (1997) and Kiesecker and 
Blaustein (1997) found that amphibians exposed to high levels of silt 
are susceptible to infection by different species of water mold of the 
genus Saprolegnia. Saprolegnia spp. are widespread in natural waters 
and commonly grow on dead organic material (Wise et al. 1995). Speer 
(1995) stated that some species of Saprolegnia are parasitic on aquatic 
invertebrates such as rotifers, nematodes, diatoms, and arthropods. 
High nitrogen and silt levels from overgrazing or other agricultural or 
urban runoff may increase the cavesnail's susceptibility to disease and 
act synergistically with other risk factors (e.g., competition from 
limpets, discussed below) to jeopardize the survival of the remaining 
individuals. Whether the Tumbling Creek cavesnail is being adversely 
affected by bacteria or water molds associated with increased loads of 
nitrogen or silt into Tumbling Creek is unknown but warrants further 
    During the December 6, 1997, survey, a few individuals of an 
unknown species of limpet (Ferrissia sp.) were discovered for the first 
time on the same substrates used by Antrobia culveri within the 
established monitoring stations (Ashley, pers. comm., September 10, 
2001). Limpets were not observed again until the January 11, 2001, 
survey, after which their numbers began to increase. By the August 31, 
2001, survey, limpet numbers had increased explosively, and the 
presence of many small limpets, as well as larger limpets with visible, 
developing embryos, indicated that reproduction was taking place 
(Ashley, pers. comm., September 10, 2001; McKenzie pers. obs.). The 
reasons why these organisms have appeared and increased in numbers 
within Tumbling Creek are unknown; it is also unknown whether they 
compete with the cavesnails for food, breeding substrates, or other 
necessary resources. Other cave invertebrates (e.g., a troglobitic 
isopod, Caecidota antricola.; a troglobitic amphipod, Stygobromus sp.; 
and a troglophilic amphipod, Gammarus sp.) coexist with Antrobia 
culveri, often on the same rocks, but it is unknown if these species 
compete with the cavesnail in any way. Additional research is needed to 
determine if local environmental changes have provided a competitive 
advantage for one or more of these species over the Tumbling Creek 

D. The Inadequacy of Existing Regulatory Mechanisms

    The primary cause of the decline of the Tumbling Creek cavesnail is 
unknown but is believed to be associated with factors within the 2,349-
hectare (5,804-acre) delineated recharge area that have adversely 
affected the water quality of Tumbling Creek. Federal, State, and local 
laws have not been sufficient to prevent past and ongoing impacts to 
areas within the cave's delineated recharge area. Antrobia culveri is 
listed as critically imperiled globally (G1) by The Nature Conservancy, 
as well as critically imperiled in the State (S1) on the Missouri 
Species of Conservation Concern Checklist (Missouri Natural Heritage 
Program 2001). The designation as G1/S1 on this checklist, however, 
provides no legal authority, but is simply utilized for planning and 
communication purposes (Missouri Natural Heritage Program 2001). 
Nonetheless, the species currently receives some protection under the 
Wildlife Code of Missouri (Wildlife Code) (Missouri Department of 
Conservation 2001) as a ``biological diversity element'' (Missouri 
Natural Heritage Program 2001). ``Biological diversity elements'' are 
protected under the following general prohibitions of chapter 4 of the 
Wildlife Code (3CSR10-4.110): ``(1) No bird, fish, amphibian, reptile, 
mammal or other form of wildlife, including their homes, dens, nests 
and eggs in Missouri shall be molested, pursued, taken, hunted, 
trapped, tagged, marked, enticed, poisoned, killed, transported, 
stored, served, bought, imported, exported or liberated to the wild in 
any manner, number, part, parcel or quantity, at any time, except as 
specifically permitted by these rules and any laws consistent with 
Article IV, sections 40-46 of the Constitution of Missouri. (2) Except 
as otherwise provided in this Code, wildlife may be taken only by 
holders of the prescribed permits and in accordance with prescribed 
methods. (3) No person, corporation, municipality, county, business or 
other public or private entity shall cause or allow any deleterious 
substance to be placed, run or drained into any of the waters of this 
State in quantities sufficient to injure, stupefy or kill fish or other 
wildlife which may inhabit such waters.''
    Under the Section 6 Cooperative Agreement between MDC and the 
Service, if a species is listed as endangered under the ESA, the 
Conservation Commission of Missouri shall list the species as State 
endangered. The protection of all species in Missouri is outlined in 
Chapter 4 of the Wildlife Code and regulations pertaining to endangered 
species are listed in section 3CSR10-4.111. Under the Wildlife Code, 
citizens can possess (but not sell or purchase) up to five individuals 
of any species without a permit and when not specifically protected 
elsewhere in the code (3CSR10-9.110). However, when a species is listed 
as endangered, citizens cannot possess any individuals and can not 
import, transport, purchase, take or possess without a scientific 
collecting or special use permit. Although the term ``refuge'' is not 
defined under the Wildlife Code, there is also a provision that enables 
MDC's Director to establish refuges not to exceed 1 square mile for

[[Page 66808]]

not more than 60 days to provide essential protection to endangered 
species. Furthermore, the Wildlife Code states that a species' ``home'' 
is protected. The term ``home'' is not defined in this statute and may 
provide limited or no protection for the cavesnail's habitat. For 
instance, the creek where the cavesnail resides and the cave's recharge 
area would probably not be considered a home and thus receive no 
protection under the Wildlife Code (Bob White, MDC, Protection Division 
Chief, pers. comm., October 2, 2001).
    The Federal Cave Resources Protection Act of 1988 (18 U.S.C. 4301-
4309; 102 Stat. 4546) was passed to ``secure, protect, and preserve 
significant caves on Federal lands * * *'' and to ``foster increased 
cooperation and exchange of information between governmental 
authorities and those who utilize caves located on Federal lands for 
scientific, educational, or recreational purposes.'' Although this 
statute and a final rule to implement the Federal Cave Resources 
Protection Act on Forest Service land (59 FR 31152; June 17, 1994) 
provides protection for caves located on property owned by the Forest 
Service, they do not provide protection for caves whose recharge areas 
are within Forest Service boundaries if the caves themselves are under 
private lands, as is the case with Tumbling Creek Cave.
    The protection afforded Antrobia culveri from the above-mentioned 
statutes is limited, does not provide any protections to its habitat, 
and includes no provisions to protect areas within the delineated 
recharge area for Tumbling Creek Cave. Therefore, we conclude the most 
likely threats to the species cannot be addressed by existing 
regulatory mechanisms.

E. Other Natural or Manmade Factors Affecting Its Continued Existence

    Several other potential factors, including point and non-point 
pollution, threats from residential and commercial development, and 
recent changes to the hydrological cycle within the 2,349-hectare 
(5,804-acre) delineated recharge area supporting Tumbling Creek Cave 
may have negative effects on the species. It is possible that the 
recent decline in cavesnail numbers is attributable to some yet to be 
identified point or non-point source pollution within the cave's 
recharge area. Because the Tumbling Creek cavesnail occupies a 
permanent, flowing stream, it will likely come in contact with any 
deleterious chemical or other material that enters the cave's recharge 
system. Silt deposition has been identified as a potential problem, 
especially to younger cohorts of the cavesnail's population, but 
additional research is needed to determine if other contaminants are 
potentially involved. (See Factor A above.)
    Non-point source pollution may be a problem in a significant 
portion of the recharge area that feeds Tumbling Creek Cave. Potential 
sources of pollution include the drainage of barnyard and feedlot 
wastes and the discharge of treated sewage into sinkholes and losing 
streambeds within the cave's recharge area. The water quality of 
Tumbling Creek is also threatened due to accidental spills into 
sinkholes or losing stream valleys feeding Tumbling Creek Cave from 
State and county highways passing through the recharge area. Such 
sources of pollution have been identified as potential problems for 
ground water in the Springfield-Salem Plateaus of southern Missouri 
(including the watershed that encompasses Tumbling Creek and its 
identified recharge zone) (Harvey 1980). The decline in numbers of the 
Tumbling Creek cavesnail may be due to one or several sources of 
pollution that have resulted in a deterioration of water quality within 
the recharge area for Tumbling Creek as outlined in Factor A. In 
comparing ground-water quality of sites within the Ozark Plateaus 
(including SW Missouri) with other National Water-Quality Assessment 
Program (NAWQA) sites, Petersen et al. (1998) documented that: (1) 
nitrate concentrations in parts of the Springfield Plateau aquifer were 
higher than in most other NAWQA drinking-water aquifers, and (2) 
volatile organic compounds were detected more frequently in drinking-
water aquifers within the Ozark Plateaus than in most other drinking-
water aquifers. Tumbling Creek Cave is within the NAWQA study 
boundaries; consequently, the cavesnail could be threatened from these 
contaminants. Although no detailed water analyses have yet been 
performed on Tumbling Creek, an instrumentation package to measure 
water quality parameters will be installed in Tumbling Creek cave 
during the fall of 2001.
    Aley (pers. comm., Jan. 19, 2001) postulated that the decline in 
cavesnail numbers may actually be because of too much gray bat guano 
that could deplete oxygen levels in Tumbling Creek, especially during 
periods of reduced flows as occurred during 1999-2001. What importance 
gray bat guano plays in the life history requirements of the Tumbling 
Creek cavesnail is yet to be tested experimentally. The instrumentation 
package mentioned above will provide data on dissolved oxygen levels 
once it is installed.
    Tumbling Creek Cave is approximately 25 to 30 miles southeast of 
Branson, Missouri, which is one of the most rapidly expanding areas in 
the State due to tourism, outdoor recreation, and entertainment 
developments. If recent trends continue, it has been projected that the 
number of visitors attracted to this area would increase from an 
estimated level of 6 million in 1992 to11 million by the year 2015. The 
accompanying growth in entertainment- and recreation-related activities 
will place even greater demands on this area of the State (Mullen and 
Keith 1992). Tumbling Creek Cave is 2 to 3 miles northwest of Bull 
Shoals Lake which is also undergoing additional real estate 
development. Consequently, it is likely that sections of the recharge 
zone for Tumbling Creek Cave will be adversely affected by real estate 
development and related construction and land management activities.
    Another potential threat to the species results from the close 
hydrologic association of Tumbling Creek with nearby Bull Shoals Lake. 
Occasional high water levels in this CE reservoir are believed to cause 
water to backup into the cave stream, threatening roosting bats and the 
cavesnail (Aley, pers. comm., July 16, 2000). The CE is considering 
raising the conservation pool of the reservoir by 10 feet, which will 
likely increase the frequency and duration of the backup events in 
Tumbling Creek Cave.
    Climatic changes, especially recent periods of drought, may also be 
a contributing factor to the decline of the cavesnail. The National 
Oceanic and Atmospheric Administration's (NOAA) Palmer Drought Severity 
Index provides a widely recognized and accepted standard measurement of 
moisture conditions (NOAA 2001). The Index varies roughly from -6.0 
(extreme drought) to +6.0 (extremely wet), with -0.49 to 0.49 
indicating near normal conditions. Since the 1974 survey by Greenlee, 
there have been 4 periods in Southwest Missouri where the Index was 
below normal for 6 months or longer and exceeded an Index value of -2.0 
(moderate drought) for some part of that period. These events occurred 
in 2-year cycles: 1980-1981; 1991-1992; 1995-1996; and 1999-2000. The 
1980-1981 drought was the most prolonged and severe, with the Index 
reaching -5.0 (extreme drought). We further analyzed a 6-year period 
between 1995 and 2000, which is the approximate period that Ashley 
conducted his cavesnail monitoring. The Index was below normal for 6 
months or more for 4 of

[[Page 66809]]

these 6 years. The years, number of months the Index was below normal, 
and the averages for the negative indices are: 1995, 6 months, average 
Index -1.54; 1996, 7 months, average Index -1.2; 1999, 6 months, 
average Index -1.29; 2000, 10 months, average Index -1.65. Preliminary 
data on NOAA's website indicate that below-normal moisture (negative 
Palmer Index) occurred in this region during the early part of 2001 but 
precipitation levels are now near normal levels.
    According to this climatic data, in 2 recent periods (1995-1996 and 
1999-2000) precipitation within the recharge area for Tumbling Creek 
Cave was below normal for an extended period. The direct or indirect 
impacts of these droughts on the cavesnail are unknown. Reduced flows 
in the cave stream, especially when combined with other threats, could 
hamper essential life history requirements (e.g., reproduction, food 
availability, water temperature); decrease the flushing of silt, guano, 
and harmful contaminants from the stream; and create an environment 
more favorable for competitors (e.g., limpets, isopods, and amphipods).
    The small population size and endemism (i.e., restricted to a 
single site) of Antrobia culveri makes it vulnerable to extinction due 
to genetic drift, inbreeding depression, and random or chance changes 
to the environment (Smith 1990) that can significantly impact cavesnail 
habitat. Inbreeding depression can result in death, decreased 
fertility, smaller body size, loss of vigor, reduced fitness, and 
various chromosome abnormalities (Smith 1990). Despite any evolutionary 
adaptations for rarity, habitat loss and degradation increase a 
species' vulnerability to extinction (Noss and Cooperrider 1994). 
Numerous authors (e.g., Noss and Cooperrider 1994; Thomas 1994) have 
indicated that the probability of extinction increases with decreasing 
habitat availability. Although changes in the environment may cause 
populations to fluctuate naturally, small and low-density populations 
are more likely to fluctuate below a minimum viable population (i.e., 
the minimum or threshold number of individuals needed in a population 
to persist in a viable state for a given interval; Gilpin and Soule 
1986; Shaffer 1981; Shaffer and Samson 1985). Current threats to the 
habitat of the Tumbling Creek cavesnail may exacerbate potential 
problems associated with its low population numbers and increase the 
chances of this species going extinct.

Reason for Emergency Determination

    Under section 4(b)(7) of the Act and regulations at 50 CFR 424.20, 
we may emergency list a species if the threats to the species 
constitute an emergency posing a significant risk to its well-being. 
Such an emergency listing expires 240 days following publication in the 
Federal Register unless, during this 240-day period, we list the 
species following the normal listing procedures. Below, we discuss 
reasons why emergency listing the Tumbling Creek cavesnail as 
endangered is necessary. In accordance with the Act, if at any time 
after we publish this emergency rule, we determine that substantial 
evidence does not exist to warrant such a rule, we will withdraw it.
    In making this determination, we have carefully assessed the best 
scientific and commercial information available regarding the past, 
present, and future threats faced by the Tumbling Creek cavesnail. 
Antrobia culveri is restricted to one cave and population monitoring 
conducted between 1996 and 2001 has indicated that a significant and 
precipitous decline in the population of the species has occurred. This 
decline has continued to the point that we are no longer finding any 
cavesnails in a part of the cave where they had always been found prior 
to 2001 by using the same monitoring methodology. From the discussion 
under Factor D of this section, it is clear that currently applicable 
Federal, State, and local laws, regulations and ordinances, 
individually and collectively, do not provide adequate protection for 
the Tumbling Creek cavesnail or its habitat or assure that the species 
will continue to survive.
    We believe that the survival of the Tumbling Creek cavesnail now 
depends on protecting the delineated recharge area of Tumbling Creek 
Cave from further degradation and restoring and rehabilitating areas 
within the recharge area to improve the water quality in Tumbling 
Creek. The few remaining individuals are vulnerable to extinction from 
ongoing threats, as well as from random natural or human-caused events 
unless sufficient habitat is protected, water quality improves, and the 
current small population greatly increases in size. The recent rapid 
population decline makes it clear that this cavesnail is on the brink 
of extinction. By this emergency listing as an endangered species, we 
believe the additional protections, funding, and recognition that 
immediately become available to the species will greatly increase the 
likelihood that it can be saved from extinction and can ultimately be 

Critical Habitat

    Critical habitat is defined in section 3, paragraph 5(A), 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 and our implementing regulations (50 CFR 
424.12) require that, to the maximum extent prudent and determinable, 
we designate critical habitat at the time the species is determined to 
be endangered or threatened. However, our budget for listing and 
critical habitat activities is currently insufficient to allow us to 
immediately complete all of the listing actions required by the Act. 
Listing Antrobia culveri without designation of critical habitat will 
allow us to concentrate our limited resources on other listing actions 
that must be addressed, while allowing us to invoke the protections 
needed for the conservation of this species without further delay. This 
is consistent with section 4(b)(6)(C)(i) of the Act, which states that 
final listing decisions may be issued without critical habitat 
designation when it is essential that such determinations be promptly 
published. If prudent and determinable, we will prepare a proposed 
critical habitat designation for A. culveri in the future at such time 
as our available resources and priorities allow.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing results in public awareness and 
conservation actions by Federal, Tribal, State, and local agencies, 
private organizations, and individuals. The Act provides for possible 
land acquisition and cooperation with the State and requires that 
recovery actions be carried out for

[[Page 66810]]

all listed species. The protection required of Federal agencies and the 
prohibitions against certain activities involving listed species are 
discussed, in part, below.
    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. If a species is listed on an emergency basis, or is listed 
under a non-emergency listing proposal, 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 
a species or to destroy or adversely modify its critical habitat. If a 
Federal agency action may adversely affect a listed species or 
adversely modify its designated critical habitat, the responsible 
Federal agency must initiate formal consultation with the Service. 
Section 7(a)(4) of the Act requires Federal agencies to confer with us 
on any action that is likely to jeopardize the continued existence of a 
proposed species or result in destruction or adverse modification of 
proposed critical habitat. Federal agency actions that may affect the 
Tumbling Creek cavesnail and may require conference and/or consultation 
with the Service include, but are not limited to, those within the 
jurisdiction of the U.S. Forest Service, U.S. Army Corps of Engineers, 
Natural Resources Conservation Service, Environmental Protection 
Agency, and Federal Highway Administration.
    The Act and its 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 
(including harass, harm, pursue, hunt, shoot, wound, kill, trap, 
capture, or collect; or attempt any such conduct), import or export, 
ship in interstate or foreign 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 Service agents and those of 
State conservation agencies.
    Permits may be issued to carry out otherwise prohibited activities 
involving endangered wildlife under certain circumstances. Regulations 
governing permits are codified at 50 CFR 17.22 and 17.23. For 
endangered species, such permits are available for scientific purposes, 
to enhance the propagation or survival of the species, and for 
incidental take in connection with otherwise lawful activities.
    As published in the Federal Register on July 1, 1994 (59 FR 34272), 
it is the Service's policy to identify to the maximum extent 
practicable at the time a species is listed those activities that would 
or would not constitute a violation of section 9 of the Act. The intent 
of this policy is to increase public awareness of the effect of the 
listing on proposed and ongoing activities within a species' range.
    We believe that, based on the best available information, the 
following actions are not likely to result in a violation of section 9, 
provided these actions are carried out in accordance with any existing 
regulations and permit requirements:
    (1) Possession of a Tumbling Creek cavesnail legally acquired prior 
to the effective date of this rule;
    (2) Actions that may affect the Tumbling Creek cavesnail that are 
authorized, funded, or carried out by a Federal agency, when the action 
is conducted in accordance with an incidental take statement issued by 
the Service under section 7 of the Act;
    (3) Actions that may affect the Tumbling Creek cavesnail that are 
not authorized, funded, or carried out by a Federal agency, when the 
action is conducted in accordance with an incidental take permit issued 
by the Service under section 10(a)(1)(B) of the Act. Applicants design 
a Habitat Conservation Plan (HCP) and apply for an incidental take 
permit. These HCPs are developed for species listed under section 4 of 
the Act and are designed to minimize and mitigate impacts to the 
species to the greatest extent practicable; and
    (4) Actions that may affect the Tumbling Creek cavesnail that are 
conducted in accordance with the conditions of a section 10(a)(1)(A) 
permit for scientific research or to enhance the propagation or 
survival of the species.
    We believe that the following actions could result in a violation 
of section 9; however, possible violations are not limited to these 
actions alone:
    (1) Unauthorized possession, collecting, trapping, capturing, 
killing, harassing, sale, delivery, or movement, including interstate 
and foreign commerce, or harming, or attempting any of these actions, 
of Tumbling Creek cavesnails without a permit (research activities 
where cavesnails are collected will require a permit under section 
10(a)(1)(A) of the Endangered Species Act);
    (2) Discharges or dumping of toxic chemicals, silt, or other 
pollutants (point source and non-point source pollution) within the 
recharge area of Tumbling Creek Cave that alters or degrades the water 
quality of Tumbling Creek to the point that it results in death or 
injury to individuals of the species or results in degradation of 
cavesnail occupied habitat; and
    (3) Release of exotic species (including, but not limited to, fish 
and crayfish) into Tumbling Creek that adversely affect the cavesnail.
    Questions regarding whether specific activities will constitute a 
violation of section 9 should be directed to the Field Supervisor of 
the Columbia, Missouri Field Office (see ADDRESSES section).
    Requests for copies of the regulations regarding listed species and 
inquiries regarding prohibitions and permits may be addressed to the 
U.S. Fish and Wildlife Service, Endangered Species Permits, Bishop 
Whipple Federal Building, 1 Federal Dr., Fort Snelling, MN 55111-4056 
(612/713-5343, facsimile 612/713-5292).

National Environmental Policy Act

    The Service has determined that an Environmental Assessment, as 
defined under the authority of the National Environmental Policy Act of 
1969, need not be prepared in connection with regulations adopted 
pursuant to section 4(a) of the Act, as amended. The Service published 
a notice outlining our reasons for this determination in the Federal 
Register on October 25, 1983 (48 FR 49244).

Paperwork Reduction Act

    This rule does not contain any collections of information that 
require additional Office of Management and Budget (OMB) approval under 
the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. An information 
collection related to the rule pertaining to permits for endangered and 
threatened species has OMB approval and is assigned clearance number 
1018-0094. This rule does not alter that information collection 
requirement. An agency may not conduct or sponsor, and a person is not 
required to respond to, a collection of information unless it displays 
a currently valid control number. For additional information concerning 
permits and associated requirements for endangered wildlife, see 50 CFR 
17.21 and 17.22.

References Cited

    A complete list of all references cited in this rulemaking is 
available upon

[[Page 66811]]

request from the Field Supervisor, Columbia, Missouri Field Office (see 
ADDRESSES section).


    The primary author of this proposed rule is Paul M. McKenzie, 
Ph.D., U.S. Fish and Wildlife Service, Columbia, Missouri Field Office 
(see ADDRESSES section).

List of Subjects in 50 CFR Part 17

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

Regulation Promulgation

    For the reasons given in the preamble, we amend part 17, subchapter 
B of chapter I, title 50 of the Code of Federal Regulations, as set 
forth below:


    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. Amend Sec. 17.11(h) by adding the following, in alphabetical 
order under SNAILS, to the List of Endangered and Threatened Wildlife:

Sec. 17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

                         Species                                                           Vertebrate population
---------------------------------------------------------         Historic  range            where endangered or     Status     When   Critical  Special
           Common name                Scientific name                                            threatened                    listed   habitat    rules

          *                  *                  *                  *                  *                  *                  *

          *                  *                  *                  *                  *                  *                  *
Cavesnail,.......................  Antrobia.............  U.S.A..........................  NA...................  E..........     719       NA        NA
Tumbling Creek...................  culveri..............  (MO)...........................

* * * * *

    Dated: December 10, 2001.
Marshall P. Jones, Jr.,
Acting Director, Fish and Wildlife Service.
[FR Doc. 01-31305 Filed 12-26-01; 8:45 am]