[Federal Register Volume 65, Number 39 (Monday, February 28, 2000)]
[Rules and Regulations]
[Pages 10420-10426]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-4531]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AF00


Endangered and Threatened Wildlife and Plants; Delisting of the 
Dismal Swamp Southeastern Shrew (Sorex longirostris fisheri

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service, remove the Dismal 
Swamp southeastern shrew (Sorex longirostris fisheri Merriam) from the 
List of Endangered and Threatened Wildlife. The Dismal Swamp 
southeastern shrew was listed as a threatened species in 1986 under the 
Endangered Species Act of 1973, as amended (Act). New data confirm that 
this species is more widely distributed than previously believed, is 
fairly abundant within its range, occurs in a wide variety of habitats, 
and is genetically secure. We conclude that the data supporting the 
original classification were incomplete and that the new data confirm 
that removing the Dismal Swamp southeastern shrew from the List of 
Endangered and Threatened Wildlife is warranted.

EFFECTIVE DATE: February 28, 2000.

ADDRESSES: The complete file for this rule is available for public 
inspection, by appointment, during normal business hours at the 
Virginia Field Office, U.S. Fish and Wildlife Service, P.O. Box 99, 
6669 Short Lane, Gloucester, VA 23061.

FOR FURTHER INFORMATION CONTACT: Cynthia A. Schulz at the above 
address, telephone 804/693-6694, extension 127, or facsimile 804/693-
9032.

SUPPLEMENTARY INFORMATION:

[[Page 10421]]

Background

    The Dismal Swamp southeastern shrew is a small, long-tailed shrew 
with a brown back, slightly paler underparts, buffy feet, and a 
relatively short, broad nose (Handley 1979a). It weighs 3 to 5 grams 
and measures up to 10 centimeters in length. The species was first 
described as Sorex fisheri by C.H. Merriam (Merriam 1895). Merriam's 
description was based on four specimens trapped near Lake Drummond, 
Virginia, by A.K. Fisher of the U.S. Department of Agriculture's Bureau 
of Biological Surveys. Rhoads and Young (1897) captured a specimen in 
Chapanoke, Perquimans County, North Carolina, that seemed intermediate 
between S. fisheri and the southeastern shrew (Sorex longirostris 
Bachman) (Handley 1979b). Jackson (1928) subsequently reduced S. 
fisheri to a subspecies of S. longirostris. Three subspecies of 
southeastern shrew are now recognized--Sorex longirostris eionis, which 
occurs in the northern two-thirds of peninsular Florida (Jones et al. 
1991); S. l. fisheri, which occurs in southeastern Virginia and eastern 
North Carolina; and S. l. longirostris, which occurs in the rest of the 
range that extends through eastern Louisiana, eastern Oklahoma, and 
Missouri, then eastward through central Illinois and Indiana, southern 
Ohio, and Maryland. Jones et al. (1991) examined the taxonomic status 
of these three subspecies and verified substantial size differences. 
Jones et al. (1991) found that S. l. eionis was significantly larger in 
four cranial measurements when compared with the other two subspecies; 
S. l. fisheri was significantly larger in one cranial and one external 
measurement; and S. l. longirostris had a relatively short palate and 
rostrum, narrow skull, and short foot and tail. This study confirmed 
the subspecific status of S. l. fisheri.
    Apart from a litter of five young found in a nest in the Dismal 
Swamp in 1905, little is known about reproduction or other life history 
features of Sorex longirostris fisheri (Handley 1979b). However, more 
is known about the life history of other Sorex species, and this 
information may apply to S. l. fisheri. Sorex longirostris reproduces 
from March through October, and two litters are likely born each year, 
with one to six young produced per litter (Webster et al. 1985). Nests 
are shallow depressions lined with dried leaves and grasses and are 
usually associated with rotting logs (Webster et al. 1985). Young 
shrews grow rapidly and are almost adult size when they leave the nest 
(Jackson 1928). Sorex longirostris forage on spiders, crickets, 
butterfly and moth larvae, slugs, snails, beetles, centipedes, and 
vegetation (Webster et al. 1985, Whitaker and Mumford 1972). Little 
information is available about the daily activity patterns of S. 
longirostris. They forage intermittently throughout the day and night 
in all seasons, seem to be most active after rains and during periods 
of high humidity, and do much of their foraging in the leaf litter or 
in tunnels in the upper layers of the soil (Jackson 1928).
    The Dismal Swamp, the type locality for Sorex longirostris fisheri, 
is a forested wetland with a mosaic of habitat types located in 
southeastern Virginia and adjacent North Carolina. Within the Dismal 
Swamp, S. l. fisheri has been found in a variety of habitat types, 
including recent clearcuts, regenerating forests, young pine 
plantations, grassy and brushy roadsides, young forests with shrubs and 
saplings, and mature pine and deciduous forests (Padgett 1991, Rose 
1983). Sorex longirostris fisheri has also been collected in utility 
line rights-of-way. The highest densities of S. l. fisheri occur in 
early successional stage habitats and the lowest densities in mature 
forests (Everton 1985), although mature forests are likely to be 
important to the survival of the shrew during periods of drought or 
fire. Densities of southeastern shrews in early successional stage 
habitats are 10 to 30 per hectare (Rose 1995).
    Until recently, the distribution of Sorex longirostris fisheri was 
considered coincidental with the historical boundaries of the Dismal 
Swamp (Handley 1979a, Hall 1981, Rose 1983). After collection of the 
original type series, additional S. l. fisheri specimens were collected 
from similar habitats in the Dismal Swamp between 1895 and 1902. Prior 
to 1980, only 20 specimens of S. l. fisheri were known. In 1980, 15 S. 
longirostris fisheri were collected in pitfall traps in Suffolk, 
Virginia, from the northwest section of the Great Dismal Swamp National 
Wildlife Refuge (Refuge) located in North Carolina and Virginia (Rose 
1981).
    From December 1980 through July 1982, researchers established 37 
pitfall grids in Currituck and Gates Counties, North Carolina and the 
Cities of Chesapeake, Suffolk, and Virginia Beach and Isle of Wight and 
Surry Counties, Virginia (Rose 1983). This trapping produced 24 
specimens from 10 populations classified as Sorex longirostris fisheri, 
62 specimens from 9 populations classified as intergrades, and 30 
specimens from 7 populations classified as S. l. longirostris. Three 
grids each contained one specimen classified as S. l. longirostris, 
while the remaining specimens were classified as S. l. fisheri. Rose 
(1983) determined that S. l. fisheri was associated with the Dismal 
Swamp proper, except for a population north of the Refuge and another 
population east of the Refuge. A narrow zone of hybridization (these 
populations contained specimens that represent the parent stocks and 
individuals that may be hybrids) was found to border the Dismal Swamp 
running approximately north/south along its western edge and running 
northwest/southeast adjacent to the southeastern corner of the Refuge. 
Sorex longirostris longirostris was found to the east and west of the 
Dismal Swamp with distinctive populations of S. l. longirostris 
occurring within 20 miles of the Dismal Swamp border (Rose 1983). The 
results of this analysis indicated that the largest Sorex were located 
within the Refuge and the smallest Sorex were located at greater 
distances from the Refuge, with specimens of intermediate size on the 
margins of the Refuge. This finding suggested that interbreeding of the 
two subspecies might be occurring, particularly at the margins of the 
Refuge. Rose (1983) tentatively recommended that S. l. fisheri be 
listed as threatened primarily because of the potential for contact and 
interbreeding with S. l. longirostris. ``If widespread, this 
interbreeding can result in an alteration of the gene pools of both 
subspecies in the zone of contact, and the integrity of both subspecies 
may be lost in the extreme'' (Rose 1983).
    Additional study of Sorex was conducted from October 1986 through 
June 1989, focusing within the Refuge but also including outlying areas 
of the historical Dismal Swamp (Padgett 1991). Particular emphasis was 
placed on determining whether the nominate subspecies might be 
expanding into the remaining Dismal Swamp proper and interbreeding with 
Sorex longirostris fisheri. Padgett's (1991) study indicated that S. l. 
fisheri was restricted to the historic Dismal Swamp and that no strong 
evidence existed that S. l. longirostris was using roadways to enter 
the interior of the Refuge. Between 1989 and 1991, Erdle and Pagels 
(1991) collected shrews to further delineate the distributions of S. l. 
fisheri and S. l. longirostris in Virginia. Sampling was conducted in 
much of the historic Dismal Swamp east of the Refuge and north of the 
Virginia-North Carolina State line. Shrews referable to both taxa and 
intergrades were represented in the 26 Sorex trapped. These findings 
supported the hypothesis that S. l.

[[Page 10422]]

longirostris might be moving into areas of the historical Dismal Swamp. 
During the 1990s, many additional areas were surveyed within the 
historical Dismal Swamp in Virginia; the specimens found were referable 
to S. l. fisheri or S. l. longirostris or were of intermediate size.
    Although researchers had significant information on the 
distribution of Sorex longirostris fisheri in Virginia, knowledge of 
the species in North Carolina was sparse. In the early 1980s, D.W. 
Webster from the University of North Carolina-Wilmington collected 
Sorex longirostris from southeastern North Carolina (D.W. Webster, 
pers. comm. 1997). Using the existing range maps for S. longirostris, 
Webster determined the specimens were S. l. longirostris. In the late 
1980s, Webster collected S. longirostris from Beaufort County, North 
Carolina and realized that those specimens looked the same as those 
collected from southeastern North Carolina. Still using the existing 
range maps (Webster, pers. comm. 1997), assumed these specimens were S. 
l. longirostris. Webster (1992) summarized historical locations of S. 
l. fisheri in North Carolina, indicating collection of S. l. fisheri 
from Camden, Currituck, and Gates Counties, and that S. l. fisheri 
probably inhabits parts of Chowan, Pasquotank, and Perquimans Counties. 
Webster continued to collect shrews from coastal North Carolina 
throughout the early 1990s (D.W. Webster, pers. comm. 1997).
    In January 1994, Webster visited the Smithsonian's National Museum 
of Natural History and compared his specimens, collected from 
southeastern North Carolina and Beaufort and Gates Counties, North 
Carolina, to the specimens at the Smithsonian. He realized that his 
specimens were of the same size as the voucher specimen for Sorex 
longirostris fisheri from Lake Drummond, the type locality. Charles O. 
Handley, at the time curator of mammals for the museum, agreed with 
Webster that these shrews were referable to S. l. fisheri based on 
size. Based on that information, Webster hypothesized that the 
``dividing line'' between S. l. fisheri and S. l. longirostris may be 
somewhere between Wilmington, North Carolina and Charleston, South 
Carolina.
    In May 1994, Webster visited the North Carolina State Museum of 
Natural Sciences and found a series of relatively large Sorex 
longirostris (not identified to subspecies) from Croatan National 
Forest (Jones, Craven, and Carteret Counties) in North Carolina (U.S. 
Fish and Wildlife Service 1995). He presumed that this series of shrews 
was S. l. fisheri based on his trip to the Smithsonian (D.W. Webster, 
pers. comm. 1997). The State museum also had specimens of southeastern 
shrews from Chowan, Bladen, and Brunswick Counties that Webster assumed 
were S. l. fisheri (D.W. Webster, pers. comm. 1997). In May and June 
1994, Webster collected S. longirostris near the town of Warsaw in 
Duplin County, midway between Wilmington and Raleigh, North Carolina. 
He determined that these specimens were referable to S. l. fisheri 
(D.W. Webster, pers. comm. 1997).
    Webster et al. (1996a, 1996b) compared Sorex longirostris specimens 
from east-central and southeastern North Carolina to specimens from the 
Dismal Swamp. They also examined specimens from Charleston County, 
South Carolina (near the type locality for S. l. longirostris), and 
Citrus County, Florida (the type locality for S. l. eionis), and 
representative samples of S. longirostris from throughout the 
southeastern United States. They concluded that S. l. fisheri is much 
more widespread and ubiquitous than previously believed. Webster's 
group undertook an analysis of physical characteristics to better 
delineate the geographic distribution of S. l. fisheri in Virginia and 
North Carolina. This analysis used 626 S. longirostris from the 
southeastern United States (15 from Florida, 375 from North Carolina, 
159 from Virginia, and the remaining 77 from Alabama, the District of 
Columbia, Indiana, Kentucky, Maryland, Mississippi, Missouri, South 
Carolina, and Tennessee). The analysis included six cranial 
measurements, palatal length, and braincase length. If available from 
specimen tags, the total specimen length, tail length, hind foot 
length, and weight were also used. Head and body length or the 
difference between total length and tail length were determined where 
possible. Significant geographic variation occured in all cranial 
measurements; samples from southeastern Virginia, eastern North 
Carolina, and southern Georgia and Florida had much larger cranial 
characteristics than samples from elsewhere in the range. The 
significant geographic variation in external measurements and weight 
typically followed the same pattern. A two-dimensional plot of the 
samples formed three clusters: (1) shrews from Georgia and Florida that 
have longer and overall much wider crania; (2) shrews from southeastern 
Virginia and eastern North Carolina that have longer crania with 
relatively narrower rostra; and (3) shrews from elsewhere in the range 
that were smaller in all cranial measurements. This plot explained 93.2 
percent of the total morphometric variation exhibited in S. 
longirostris crania. Shrews from the piedmont and mountains of Virginia 
and North Carolina were more similar to specimens from the Mississippi 
and Ohio River basins than they were to those from the mid-Atlantic 
coast.
    Webster et al. (1996a, 1996b) established 84 survey sites in a wide 
range of habitats throughout North Carolina and Virginia to ensure that 
both Sorex longirostris longirostris and S. l. fisheri would be 
captured. Of the 84 sites, 49 (58.3 percent) were located in abandoned 
fields and powerline rights-of-way that were dominated by herbaceous 
vegetation typical of early stages of succession. The other 35 sites 
(41.7 percent) were dominated by arborescent vegetation, including such 
forest types as longleaf pine/turkey oak, pocosin/bay, Atlantic white 
cedar, shortleaf pine, riparian hardwood, and cove hardwood. The 
researchers collected 18 species of small mammals, and S. longirostris 
was the most abundant and ubiquitous. The researchers divided survey 
sites into two groups, those occurring in the newly delineated range of 
S. l. fisheri and those occuring in the newly delineated range of S. l. 
longirostris. Within each the results were similar. Within its 
geographic distribution, S. l. fisheri was the most abundant small 
mammal, or shared that distinction with other species at 31 of the 84 
sites sampled. Sorex longirostris fisheri was especially abundant in 
forested habitats in and adjacent to the Refuge, comprising 84 percent 
of the specimens taken. The only habitat sampled where S. l. fisheri 
was absent was xeric longleaf pine/turkey oak. Both taxa were found in 
a wide range of habitat types and moisture regimes, from early 
successional to mature second-growth forest and from well-drained 
uplands to seasonally inundated wetlands. Webster (1996a, 1996b) 
concluded that ``* * *even the smallest specimens from relatively dry, 
upland sites in the Dismal Swamp region clearly are assignable to S. l. 
fisheri.''
    Gurshaw (1996) examined allozyme variability in specimens of the 
southeastern shrew from North Carolina and Virginia to identify 
characters that differentiate Sorex longirostris fisheri and S. l. 
longirostris and to determine if there are similarities between shrews 
from the Dismal Swamp region and the coastal plain of southeastern 
North Carolina. She found that shrews from the coastal plain of 
southeastern North Carolina grouped most closely with those from the 
Dismal Swamp. The

[[Page 10423]]

author found an allele in the shrews from the coastal plain that 
represents a genetic distinction from S. l. longirostris. Distribution 
of this allele appeared to follow the Fall Line, the boundary between 
the piedmont plateau and upper coastal plain in the southeastern United 
States.
    Webster et al. (1996a, 1996b) concluded that Sorex longirostris 
fisheri ``* * * has a much broader geographic distribution than 
previously believed, extending from southeastern Virginia to 
southeastern North Carolina along the outer coastal plain. In Virginia, 
all specimens examined from Isle of Wight County, the City of 
Chesapeake, and the City of Virginia Beach are referable to S. l. 
fisheri, whereas those from Surry, Sussex, and Southampton Counties are 
assignable to S. l. longirostris. In North Carolina, S. l. fisheri is 
distributed throughout the coastal counties as far south as New 
Hanover, Brunswick, and Columbus Counties.'' Since the conclusion of 
that study, S. l. fisheri has been documented in Hyde County, North 
Carolina (D.W. Webster, pers. comm. 1997). No trapping for S. 
longirostris has been conducted in Onslow, Martin, Pamlico, or Burtie 
Counties, North Carolina (D.W. Webster, pers. comm. 1997). Webster 
(pers. comm. 1997) does not have any records of S. l. fisheri from 
Pasquotank County, although surveys were conducted there in 1995. At 
the time of listing, Pasquotank County was listed as a county of 
occurrence for S. l. fisheri, however, the literature cited does not 
support this designation.
    At the time of listing, Sorex longirostris fisheri was believed to 
occur in only two cities in Virginia and four counties in North 
Carolina. Sorex longirostris fisheri is now known to occur in Beaufort, 
Bladen, Brunswick, Camden, Carteret, Chowan, Columbus, Craven, 
Currituck, Dare, Duplin, Gates, Greene, Hyde, Jones, Lenoir, New 
Hanover, Pender, Perquimans, Robeson, Scotland, Tyrrell, and Washington 
Counties in North Carolina and Chesapeake, Suffolk, and Virginia Beach 
Cities and Isle of Wight County in Virginia. Information gaps still 
exist in the distribution of S. l. fisheri in North Carolina and 
potentially South Carolina. Jones et al. (1991) noted a sample of Sorex 
specimens from coastal South Carolina that appeared to be similar to S. 
l. fisheri, but substantiation is needed regarding the taxonomy of 
these specimens.

Previous Federal Action

    On December 30, 1982, in our Review of Vertebrate Wildlife for 
Listing as Endangered or Threatened Species (47 FR 58454), we 
designated the Dismal Swamp southeastern shrew as a category 2 
candidate species, meaning that a proposal to list the subspecies as 
threatened or endangered was possibly appropriate, but that substantial 
biological data were not available at that time to support such a 
proposal. Rose (1981, 1983) and Everton (1985) conducted pre-listing 
status surveys that documented large shrews within the Refuge, small 
shrews outside the Refuge, and intermediate-sized shrews near the 
Refuge boundaries.
    On July 16, 1985, we published a proposed rule to list the Dismal 
Swamp southeastern shrew as a threatened species (50 FR 28821). The 
final rule to list the species was published in the Federal Register on 
September 26, 1986 (51 FR 34422), and became effective on October 27, 
1986. The reasons for listing the Dismal Swamp southeastern shrew were 
habitat loss and alteration and possible loss of genetic integrity 
through interbreeding with S. l. longirostris.
    In the early 1990s, a group of biologists from Virginia held 
meetings to discuss information and issues related to the recovery of 
the Dismal Swamp southeastern shrew. Initially, most of the effort was 
focused in Virginia because of the development pressure occurring 
there. In 1992, biologists from North Carolina were included in the 
group. The Service then convened an official recovery team, and held 
the first meeting in February 1993.
    The recovery team completed a draft recovery plan in July 1994, and 
we published a notice of availability for the plan in the Federal 
Register (59 FR 37260). The recovery plan was finalized on September 9, 
1994, and updated on June 13, 1995.
    In March 1995, based on questions raised by D.W. Webster about the 
shrew's distribution and taxonomy, the Virginia Department of Game and 
Inland Fisheries and the Service funded studies to determine if large 
shrews are distributed from the Dismal Swamp region southward 
throughout the coastal plain of North Carolina, and if the large shrews 
from coastal North Carolina are similar to S. l. fisheri from near the 
type locality. A combination of morphometric and genetic analyses was 
proposed to answer these questions. The results of the morphological 
and genetic analyses that followed are discussed in detail in the 
Background section of this rule.
    In May 1996, we received reports on morphometric variation among 
the three Sorex longirostris subspecies (Webster et al. 1996a) and 
protein electrophoresis and allozymic variation between S. l. fisher 
and S. l. longirostris (Gurshaw 1996) and sent this information to the 
recovery team members. The recovery team convened in June 1996 to 
discuss the two reports. The consensus of the team was that the results 
of both the morphological and genetic analyses conclusively show that 
S. l. fisheri is widely distributed along the coastal plain of 
southeastern Virginia and eastern North Carolina at least as far south 
as Wilmington, North Carolina; that S. l. fisheri uses a wide variety 
of habitat types; and that S. l. fisheri is not in danger of genetic 
swamping by S. l. longirostris. However, the team agreed that the 
reports should undergo independent peer review before further action 
was taken and sent them to reviewers in June 1996. Reviewers who 
responded concurred with the conclusions of the authors and supported 
delisting. Based on comments provided by recovery team members, the 
Service, and peer reviewers, the original manuscripts were revised 
(Moncrief 1996, Webster et al. 1996b).
    Federal involvement with the Dismal Swamp southeastern shrew after 
listing has included surveys for new locations and informal and formal 
consultations under section 7 of the Act for activities involving a 
Federal action occurring in suitable habitat within the historical 
Dismal Swamp. No biological opinion reflecting a conclusion that a 
project could result in the extinction of this species has ever been 
issued.
    We published a proposed rule to remove the shrew from the List of 
Endangered and Threatened Wildlife in the Federal Register on October 
21, 1998 (63 FR 56128).

Summary of Comments and Recommendations

    In the October 21, 1998, proposed rule (63 FR 56128) and associated 
notifications, we invited all interested parties to submit factual 
reports or information that might contribute to the development of a 
final rule. We also contacted appropriate State and Federal agencies, 
county governments, scientific organizations, members of the recovery 
team, and other interested parties and asked them to comment. We 
published legal notices soliciting comments in one North Carolina 
newspaper, The Wilmington Journal, on November 5, 1998. Legal notices 
were also published in two Virginia newspapers, The Virginian-Pilot and 
The Suffolk News-Herald, on November 1, 1998.
    Ten individuals or organizations submitted comment letters. Two 
peer reviewers supported the delisting, and one of the reviewers 
provided additional pertinent information that was incorporated into 
the final rule. The

[[Page 10424]]

Virginia Department of Game and Inland Fisheries; U.S. Army Corps of 
Engineers, Wilmington District; Isle of Wight County, Virginia; and the 
North Carolina Department of Environment and Natural Resources, 
Division of Parks and Recreation, and North Carolina Natural Heritage 
Program supported the delisting. The Virginia Department of 
Conservation and Recreation, Hampton Roads Planning District Commission 
(representing Cities of Chesapeake, Suffolk, and Virginia Beach), and 
Virginia Department of Environmental Quality had no comment. The 
Virginia Department of Agriculture and Consumer Services stated that 
delisting would have no adverse impacts on their regulatory 
responsibilities. We received no additional written or oral comments 
during the comment period.

Summary of Factors Affecting the Species

    After a thorough review and consideration of all information 
available, we have determined that the Dismal Swamp southeastern shrew 
should be removed from the List of Endangered and Threatened Wildlife. 
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. Regulations at 50 CFR 424.11 require that certain factors be 
considered before a species can be listed, reclassified, or delisted. 
These factors and their application to the Dismal Swamp southeastern 
shrew (Sorex longirostris fisheri Merriam) are as follows:
    A. The present or threatened destruction, modification, or 
curtailment of its habitat or range. Extensive habitat alteration has 
occurred within the area historically occupied by the Dismal Swamp. At 
the beginning of the twentieth century, the Dismal Swamp occupied 2,000 
to 2,200 square miles (mi \2\) (5,200 to 5,700 square kilometers (km 
\2\)). Currently, less than 320 mi \2\ (830 km \2\) of the historical 
Dismal Swamp remain, 189 mi \2\ (490 km \2\) of which are protected 
within the Refuge and the Great Dismal Swamp State Park in North 
Carolina. Remnants of the historical Dismal Swamp outside Refuge and 
State Park boundaries and land beyond the historical Dismal Swamp 
boundaries are disappearing due to development associated with the 
rapid growth of the Hampton Roads metropolitan area of southeastern 
Virginia. Agricultural and silvicultural conversions (especially in 
North Carolina) also contribute significantly to habitat loss. Habitat 
loss was a primary reason for listing the Dismal Swamp southeastern 
shrew, considered at the time to be endemic to the historical Dismal 
Swamp. However, because the species is now known to occur across a much 
larger area and in a wider variety of habitats, this threat is not as 
significant as was believed at the time of listing.
    B. Overutilization for commercial, recreational, scientific, or 
educational purposes. At present, the only known method for studying or 
monitoring the Dismal Swamp southeastern shrew involves lethal 
collection with pitfall traps. Researchers have been permitted to take 
individuals of the species to gain an understanding of its taxonomy, 
ecology, and distribution. However, because the Dismal Swamp 
southeastern shrew has a high reproductive potential and a rapid 
maturation rate, limited collection of individuals is not considered 
detrimental to healthy populations. Utilization for commercial, 
recreational, or educational purposes is not known to occur.
    C. Disease or predation. Southeastern shrews are subject to some 
predation, most frequently by owls, snakes, opossums, and domestic cats 
and dogs (French 1980, Webster et al. 1985). The number of dead shrews 
found in woods and on roads suggests that many predators reject the 
shrew, probably because of the bad taste associated with their musk 
glands (French 1980). We have no evidence that predation or disease is 
a significant threat to the Dismal Swamp southeastern shrew.
    D. The inadequacy of existing regulatory mechanisms. Wetland 
habitats for the Dismal Swamp southeastern shrew will continue to 
receive protection indirectly under Section 404 of the Clean Water Act, 
which requires the Department of the Army, Corps of Engineers to 
regulate certain activities affecting ``waters of the United States,'' 
including wetlands. Delisting the Dismal Swamp southeastern shrew 
removes Federal prohibitions against take and activities involving a 
Federal action that would jeopardize the continued existence of the 
species. However, because of its wide distribution and use of a wide 
variety of habitats, the removal of these protections afforded by the 
Act will not pose a significant threat to the Dismal Swamp southeastern 
shrew.
    The Dismal Swamp southeastern shrew is listed as threatened by the 
State of Virginia. Virginia's Endangered Species Act of 1972, as 
amended (Code of Virginia Section 29.1-564-568), prohibits the taking, 
transportation, processing, sale, or offer for sale of endangered and 
threatened species except as permitted. The Virginia Department of Game 
and Inland Fisheries provides general protection to wildlife through 
State law Section 29.1-521, which prohibits their possession and 
capture, including the attempt to capture, take, kill, possess, offer 
for sale, sell, offer for purchase, purchase, deliver for 
transportation, transport, cause to be transported, receive, export, 
import in any manner or in any quantity except as specifically 
permitted.
    The Dismal Swamp southeastern shrew is listed as threatened by the 
State of North Carolina. The species is protected by North Carolina 
general statute Article 25, section 113-337, which makes it unlawful to 
take, possess, transport, sell, barter, trade, exchange, export, or 
offer for sale, barter, trade, exchange, or export, or give away for 
any purpose including advertising or other promotional purpose any 
animal on a protected wild animal list, except as authorized according 
to the regulations of the North Carolina Wildlife Resources Commission.
    All States have the option of retaining the Dismal Swamp 
southeastern shrew on their various lists. Both the States of Virginia 
and North Carolina support the delisting. The State of North Carolina 
plans to delist the Dismal Swamp southeastern shrew (H. LeGrand, North 
Carolina Natural Heritage Program, pers. comm. 1997). However, because 
of its wide distribution and use of a wide variety of habitats, the 
removal of State protection will not constitute a significant threat to 
the species.
    E. Other natural or manmade factors affecting its continued 
existence. One of the reasons for listing the Dismal Swamp southeastern 
shrew was concern regarding the possible loss of genetic integrity 
through interbreeding with the nominate subspecies. Gurshaw (1996) 
examined allozyme variability in specimens of the southeastern shrew 
from North Carolina and Virginia. She found an allele in the shrews 
from the coastal plain that represents a genetic distinction from Sorex 
longirostris longirostris and that appeared to follow the Fall Line. 
The author stated, ``A cline for this allele may be shifted in the 
direction of dispersal in proportion to the direction of gene flow 
through barriers such as the Fall Line and population size. If the 
populations containing [this] allele are small, they will not have as 
many individuals dispersing* * *and gene flow may be restricted 
(Endler, 1977). In this study, however, the opposite appears to be 
happening. Populations with [this allele] are widespread in eastern 
North Carolina and southeastern Virginia, with gene flow carrying 
[this] allele above the

[[Page 10425]]

Fall Line in central North Carolina.'' She concluded that genetic 
swamping within the Dismal Swamp region was not evident.
    Webster et al. (1996a, 1996b) found that intergradation between 
Sorex longirostris fisheri and S. l. longirostris is evident in 
specimens from the inner coastal plain of Virginia and North Carolina. 
The zone of intergradation is relatively narrow in Virginia and 
relatively wide in North Carolina, commensurate with the relative size 
of the inner coastal plain. Shrews from samples immediately to the east 
and west of the present Dismal Swamp were slightly smaller than shrews 
from the Dismal Swamp in cranial and external measurements. Padgett et 
al. (1987) noted this trend. However, when compared with specimens from 
throughout the range of the species, these shrews are referable to S. 
l. fisheri.
    The following summarizes available information regarding potential 
environmental contaminant threats to the Dismal Swamp southeastern 
shrew throughout its range. In 1987 and 1989, we conducted a 
preliminary study (Ryan et al. 1992) within the Refuge to determine if 
contaminants were impacting fish and small mammals. All water (metal-
laden leachate and groundwater) draining the Suffolk City Landfill, at 
the time a federally designated Superfund site, enters the Refuge. This 
landfill received industrial and domestic wastes, including 30 tons of 
organophosphate pesticides in the 1970s. Numerous automobile junkyards 
border the Refuge to the north and drain into the Dismal Swamp and the 
Refuge. Oil, grease, metals, polycyclic aromatic hydrocarbons (PAHs) 
and alkanes (PAHs and alkanes are components of petroleum products) are 
common constituents of junkyard and roadway runoff. Agricultural fields 
to the north and west of the Refuge contribute surface runoff that may 
contain residual herbicides, insecticides, and fungicides.
    Our study (Ryan et al. 1992) included analyses for contaminant 
residues in the short-tailed shrew (Blarina brevicauda). Short-tailed 
shrews trapped near the East Ditch displayed elevated levels of lead, 
mercury, and several organochlorine pesticides. The lead levels for 
short-tailed shrews exceeded normal ranges and fell within the range 
for lead toxicosis according to Ma (1996). Small mammal lead toxicosis 
symptoms may include neurological dysfunction, reproductive disorders 
(including stillbirths), liver and kidney failure, etc. Apart from 
overt symptoms, asymptomatic effects may occur at lower levels and have 
significant effects on animal behavior, yet be difficult to evaluate 
and/or document. Ryan et al. (1992) found that mercury levels for 
short-tailed shrews collected at East Ditch, Badger Ditch, Railroad 
Ditch, and Pocosin Swamp were elevated in comparison to levels for 
short-tailed shrews collected from the study reference location and 
other sites within the Refuge. The mercury levels reported for short-
tailed shrews, although elevated when compared within study area sites, 
were below those levels reported in the literature as causing observed 
adverse effects. Organochlorine pesticide levels of short-tailed shrews 
from the East Ditch were higher than those reported from all other 
study sites. However, the levels were below those documented in the 
literature for observed adverse effects. In summary, there may be a 
contaminant concern for the Dismal Swamp southeastern shrew near the 
East Ditch of the Refuge. However, no contaminant analysis has been 
conducted on Dismal Swamp southeastern shrews, although we have 
recommended further monitoring related to this issue.
    Small mammals tend to have limited ranges, and, therefore, elevated 
levels of contaminants found in shrews from one location cannot be 
interpreted as a condition for shrews throughout the Refuge or range. 
Land uses such as agriculture, transportation, and urbanization with 
increased impervious surfaces contribute measurable levels of 
contaminants to the environment, and many persistent contaminants are 
passed through the food web. However, we do not have any information 
indicating that contaminants pose a significant threat to the continued 
existence of the Dismal Swamp southeastern shrew.
    Regulations at 50 CFR 424.11(d) state that a species may be 
delisted if (1) it becomes extinct, (2) it recovers, or (3) the 
original data for classification were in error. We have determined that 
the original data for classification of the Dismal Swamp southeastern 
shrew as a threatened species were in error. However, it is important 
to note that the original data for classification constituted the best 
available scientific and commercial information available at the time 
and were in error only in the sense that they were incomplete. Because 
Sorex longirostris from the Dismal Swamp were originally classified as 
S. l. fisheri based on morphological measurements from a limited number 
of specimens, and because specimens from areas bordering the Dismal 
Swamp did not have similar morphological measurements, taxonomists 
logically concluded that only the largest specimens were S. l. fisheri. 
Since the early 1900s, scientists have assumed that small-sized shrews 
were S. l. longirostris, resulting in erroneous classification of 
shrews found outside, and sometimes within, the historical Dismal Swamp 
boundaries. Therefore, the perception of a restricted range for S. l. 
fisheri was not a misinterpretation on the part of the Service, but a 
longstanding scientific assumption. At the time of listing, no other 
interpretation could be reasonably construed from the available data. 
We conclude that the data supporting the original classification were 
incomplete and that removal of S. l. fisheri from the List of 
Endangered and Threatened Wildlife is warranted.
    The listing of the Dismal Swamp southeastern shrew as a threatened 
species was based on the best information available and was therefore a 
valid decision at the time. The data leading to a better understanding 
of S. longirostris taxonomy were derived incrementally as a direct 
result of the recovery program, and no preceding shrew research 
anticipated the outcome of the final morphometric and genetic analyses. 
The dual effort to increase the base of available information while 
addressing the perceived threats to this subspecies was thus both 
legally and scientifically justified up to the point when new 
information yielded a significant change in the knowledge of the Dismal 
Swamp southeastern shrew's status.
    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by this species in determining to make this rule final. Based on 
this evaluation, the preferred action is to remove the Dismal Swamp 
southeastern shrew from the List of Endangered and Threatened Wildlife 
because the shrew no longer meets the definition of ``threatened'' 
under section 3 of the Act and, therefore no longer requires the 
protection afforded by the Act.
    In accordance with 5 U.S.C. 553(d), we have determined that this 
rule relieves an existing restriction and good cause exists to make 
this rule effective immediately. Delay in implementation of this 
delisting would cost government agencies staff time and monies on 
conducting section 7 consultation on actions that may affect a species 
no longer in need of protection under the Act. Relieving the existing 
restriction associated with this listed species will enable Federal 
agencies to minimize any further delays in project planning and 
implementation for actions that may affect the Dismal Swamp 
southeastern shrew.

[[Page 10426]]

Effects of the Rule

    This action results in the removal of the Dismal Swamp southeastern 
shrew from the List of Endangered and Threatened Wildlife. Federal 
agencies are no longer required to consult with us to insure that any 
action they authorize, fund, or carry out is not likely to jeopardize 
the continued existence of this species. There is no designated 
critical habitat for this species. Federal restrictions on taking no 
longer apply. The 1988 amendments to the Act require that all species 
that have been delisted due to recovery be monitored for at least 5 
years following delisting. The Dismal Swamp southeastern shrew is being 
delisted due to new information. Therefore we do not intend to monitor 
the species. We believe that sufficient habitat will remain over the 
long term to allow for the continued viability of this species. Within 
the Refuge and the Great Dismal Swamp State Park in North Carolina, 
management will continue to focus on restoring the hydrological regime 
to as close to historical conditions as possible, and efforts are being 
made to restore or maintain the habitat mosaic through forestry 
practices, all of which will benefit the shrew.

Paperwork Reduction Act

    Office of Management and Budget (OMB) regulations at 5 CFR 1320, 
which implement provisions of the Paperwork Reduction Act, require that 
Federal agencies obtain approval from OMB before collecting information 
from the public. Implementation of this rule will not involve any 
information collection requiring OMB approval under the Paperwork 
Reduction Act.

National Environmental Policy Act

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

Executive Order 12866

    This rule is not subject to review by the OMB under Executive Order 
12866.

References Cited

    A complete list of all references cited herein is available upon 
request from the Virginia Field Office (see ADDRESSES section).

Author

    The primary author of this document is Cynthia A. Schulz (see 
ADDRESSES section).

List of Subjects in 50 CFR Part 17

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

Regulation Promulgation

    Accordingly, we amend part 17, subchapter B of chapter 1, title 50 
Code of Federal Regulations, 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.


Sec. 17.11  [Amended]

    2. Section 17.11(h) is amended by removing the entry for ``Shrew, 
Dismal Swamp southeastern, Sorex longirostris fisheri'' under 
``MAMMALS'' from the List of Endangered and Threatened Wildlife.

    Dated: January 18, 2000.
Jamie Rappaport Clark,
Director, Fish and Wildlife Service.
[FR Doc. 00-4531 Filed 2-25-00; 8:45 am]
BILLING CODE 4310-55-P