3 9999 06317 799 0 ■

REVIE^V OF THE ECOLOGY AND
CONSERVATION OF THE BOG TURTLE,
CLEMMYS MUHLENBERGII

J/?

DEPOSITORY

UNITED STATES DEPARTMENT OF THE INTERIOR

FISH AND WILDLIFE SERVICE

Special Scientific Report- Wildlife No. 219

Library of Congress Cataloging in Publication Data

Bury, R. Bruce.

Review of the ecology and conservation of the bog turtle, Clemmys
muhlenbergii.

(Special scientific report— wildlife; no. 219)

Supt. of Docs, no.: I 49.15/3:219
1. Bog turtle— Ecology. 2. Wildlife conservation— United States. 3. Rep-
tiles—Ecology. 4. Reptiles— United States— Ecology. I. Title. II. Series.
SK361.A256no. 219[QL666.C584] 636'.9'08s[639'.97'813] 79-607014

NOTE: Use of trade names does not imply U.S. Government endorsement of commercial products.

REVIEW OF THE ECOLOGY AND CONSERVATION OF
THE BOG TURTLE, CLEMMYS MUHLENBERGII

By R. Bruce Bury

UNITED STATES DEPARTMENT OF THE INTERIOR

FISH AND WILDLIFE SERVICE

Special Scientific Report— Wildlife No. 219
Washington, D.C. • 1979

"% WILDV^

Review of the Ecology and Conservation of the Bog Turtle,

Clemmys muhlenbergii

by

R. Bruce Bury

U.S. Fish and Wildlife Service

National Fish and Wildlife Laboratory

1300 Blue Spruce Drive

Fort Collins, Colorado 80524

Abstract

The bog turtle {Clemmys muhlenbergii) is variously considered to be secretive, uncommon, or
threatened with extinction. It has a disjunct distribution in the eastern United States, and
populations are restricted to wetlands such as bogs and swamps. The turtle appears to be an
omnivore. It is most active in the spring, and the eggs (usually three to five) are laid in late spring
or early summer. Sexual maturity in both sexes probably occurs at a plastral length of about 75
mm, when the turtles are 6 to 8 years old. Bog turtles apparently have small home ranges (about
1.3 ha or smaller). Other population features are poorly known. There is concern for the plight of
the bog turtle because of the continual loss of wetland habitat and irresponsible collecting. A
thorough survey is recommended to delineate the occurrence and abundance of the remaining
populations of the species throughout its range.

The North American bog turtle (Clemmys muhlen-
bergii Schoepff, 1801) has remained among the most
poorly known freshwater species because of its uncom-
mon and discontinuous occurrence. The literature on
the species consists mostly of numerous reports of its
discovery at new localities in the eastern United
States, and extensive descriptions based on scanty
field data. Several people have suggested that it is
threatened with extinction, whereas others have
reported that some populations are large.

Nomenclatural history, systematics, technical de-
scription, fossil records, relationships, and pertinent
life history literature of the bog turtle were reviewed
by Ernst and Bury (1977) and Bury and Ernst (1977).
The present paper summarizes the literature on behav-
ior, ecology, habitat, and management problems. This
information is offered to resolve contradictions about
the abundance of the species, to indicate gaps in the
information available about it, and to provide a per-
spective for its management and conservation.

Description

The bog turtle is clearly distinguishable in the field
(Fig. 1). The shell of adults is small, measuring 75-110
mm long; most adults are 75 to 90 mm long. The shell
and body are brown to black. There is a large, bright

orange, yellow, or red blotch on each side of the head at
the tympanum.

Males have concave plastrons and long, thick tails,
and the vent is beyond the carapacial margin; females
have high carapaces, flat plastrons, relatively short
tails, and the vent is beneath the carapace edge.

Distribution

The bog turtle has a spotty distribution, extending
from upper New York and eastern Pennsylvania south-
ward to the Appalachian Mountains in North Carolina
(Fig. 2). There are no verified records for West Vir-
ginia, southern Maryland, or northern Virginia, and a
large gap separates the northeastern populations from
colonies in the southern Appalachians (Babcock 1919;
Barton and Price 1955: Nemuras and Weaver 1974a;
Nemuras 1975; Ernst and Bury 1977).

There are numerous reports on its distribution:
Rhode Island (Babcock 1917); Connecticut (Robinson
1956; Nemuras 1975); New York (Fisher 1887; Wright
1918a, 19186; Bishop 1923; Davis 1928; Myers 1930;
Stewart 1947; Ashley 1948; Kauffeld 1949; Benton
and Smiley 1961; Zappalorti 1976); Delaware (Arndt
1972, 1975, 1977); Pennsylvania (Surface 1908;
Netting 1927; Roddy 1928; Burger 1933; Cramer 1935,
1941; Heilman 1951; Swanson 1952; Hudson 1954;

1

Fig. 1. Adult bog turtle (photograph by J. Weaver).

Behler 1970; Nemuras and Weaver 19746); New Jersey
(Fowler 1907; Conant and Bailey 1936; Grant 1966;
Bloomer and Bloomer 1973); Maryland (McCauley and
Manseuti 1943; McCauley 1945; Cooper 1949; Reed
1956; Campbell 1960; Nemuras 1965, 1966a, 19666;
Schwartz 1967; Anon. 1973; Harris 1975); Virginia
(Barton 1960; Hutchinson 1963; Nemuras 1974a); and
North Carolina (Dunn 1917; Brimley 1943; Nemuras
19746; Zappalorti 1975).

Habitat

Bog turtles live in bogs and wet meadows where sun
penetration is great and humidity high in warm
weather (Barton and Price 1955). Major descriptions of
the turtle's habitat were given by Carr (1952), Barton
and Price (1955), Nemuras (1967), Ernst and Barbour
(1972), Nemuras and Weaver (19746), Zappalorti
(1976), Ernst and Bury (1977), and Arndt (1977).

The species may live from sea level to 1,280 m. It
usually occurs below 245 m in the northern portion of
its range, but inhabits areas from 645 to 1,280 m in the

Appalachians. A few populations are known from 215
to 275 m in the Piedmont region of North Carolina
(Nemuras 1974a, 19746, 1976; Zappalorti 1975).

The bog turtle occurs in standing or slow-moving
water that has a mucky substrate, but it is not fully
aquatic. It inhabits shallow water, and often is found
with its feet wet but its carapace dry. Tryon and
Hulsey (1977) reported that captives preferred to be
either totally or partly submerged most of the time.

Bog turtles are associated with undisturbed bogs,
swamps, ponds, and wetlands that support moisture-
loving plants (Carr 1952; Campbell 1960; Nemuras
1965, 1966c; Eglis 1967; Ernst and Barbour 1972;
Nemuras 19746) such as sphagnum mosses (Sphag-
num spp.), club mosses (Lycopodium spp.), skunk
cabbage (Symplocarpus foetidus), sedges (Carex spp.),
bulrushes (Scirpus spp.), cattail (Typha latifolia),
speckled alder (Alnus rugosa), swamp-bay magnolia
(Magnolia virginiana), and swamp honeysuckle
(Rhododendron viscosum). An abundance of grassy or
mossy cover is characteristic of most areas where bog
turtles are found (Barton and Price 1955). Inasmuch as

these habitat conditions occur in areas of the eastern
United States where no bog turtles are present (Nem-
uras 1974a), other factors apparently restrict the
distribution of the species.

Food

Bog turtles apparently forage both on land and
under water during the day in warm or hot weather
(Surface 1908; Barton and Price 1955; Campbell 1960;
Eglis 1967; Ernst and Barbour 1972; Nemuras and
Weaver 19746; Nemuras 1967, 19746, 1976). Zappa-
lorti (1976) reported that they are aggressive
predators.

The diet consists principally of insects but includes
some plants and carrion. The contents of two
stomachs examined by Surface (1908) consisted of
80% insects and 20% berries. Barton and Price (1955)
found the following (in order of abundance) in two
adults from Pennsylvania: Lepidoptera larvae, Coleop-
tera adults, seeds of pondweed {Potamogeton) and
sedge, several caddis fly larval cases, cocoons of a
parasitic hymenopteran or dipteran, snails, millipede
pieces, and a crane fly wing. The feces of some adult
turtles caught in mid-August contained the exoskele-
tons of Japanese beetles {Popillia japonica).

Numerous other foods of bog turtles have been
reported: watercress and skunk cabbage (Zappalorti
1975, 1976), pondweed (Nemuras 1976), earthworms
(Nemuras and Weaver 1974a; Nemuras 1976), crayfish
(Zappalorti 1975, 1976), snails (Campbell 1960, Nem-
uras 19746; Zappalorti 1975, 1976), slugs (Zappalorti
1975, 1976), aquatic insects (Nemuras 1976), field
crickets (Zappalorti 1975), butterfly larvae (Campbell
1960), tadpoles (Nemuras 19746, 1976; Nemuras and
Weaver 1974a), bullfrogs, green and wood frogs
(Zappalorti 1975, 1976), pickerel frog (Campbell 1960),
water snake (Robotham 1963), and nestling birds
(Zappalorti 1975, 1976).

Information is inadequate to describe seasonal
changes or age differences in feeding habits. There are
no detailed quantitative studies of diet. A stomach
pump would enable examination of ingested food
without killing the turtles (for technique, see Legler
1977).

Seasonal Activities and Migrations

A. J. Barton (in Eglis 1967) described a migratory
pattern of bog turtles in a Pennsylvania population: in
April or May the turtles moved upstream to feeding
and egg-laying sites in areas of shallower water, and
near the end of August they returned to hibernation
areas where the water is deeper. One turtle moved at

Fig. 2. Distribution of the bog turtle in the eastern United
States (from Ernst and Bury 1977. based on Nemuras
1975).

an average rate of 17 m a day over a distance of 185-
215 m.

Most activity occurs from April to June and in Sep-
tember (Campbell 1960; Nemuras 1967, 19746; Nem-
uras and Weaver 1974a, 19746; Ernst and Barbour
1972; Zappalorti 1976). In Pennsylvania, Ernst (1977)
found turtles active from late March to late Sep-
tember; most activity was in May. The latest recorded
activity was in October. In Delaware, Arndt (1977)
also found that most activity was in May. The turtles
apparently hibernate for about 6 months, from mid-
autumn to early spring. When they emerge from hiber-
nation, they spend much time basking. They are often
found basking in spring and early summer, and seem-
ingly are less active in midsummer, when the soggy
habitat becomes drier. Barton and Price (1955)
reported that the species is active in midsummer, but
McCauley and Manseuti (1943), Ernst and Barbour
(1972), and Nemuras and Weaver (1974a) wrote that it
may estivate then. Overnight and during cool, cloudy
spells, the turtles bury themselves in the soil or marsh-
land (Barton and Price 1955). In North Carolina, Nem-
uras (19746) reported seeing turtles roaming about in
the rain.

Daily Activities

In Pennsylvania, Ernst and Barbour (1972) saw the
bog turtle only during the warmer parts of the day
(1100-1600 h), and Barton and Price (1955) stated that
it rarely becomes active before 1000 h, even in mid-
summer. In North Carolina, Nemuras (19746) ob-
served basking until dusk. Zappalorti (1975, 1976)
found turtles to be active as early as 0700 h and as late
as 1800 h in June and July. In Delaware, Arndt (1977)
reported that activity occurred between 0830 and
1840 h with most records from 1200 to 1700 h.

Several workers have suggested that bog turtles
remain active at higher temperatures than other
northeastern turtles (Cramer 1935; Barton and Price
1955; Eglis 1967; Ernst and Barbour 1972), but recent
evidence does not support this contention. Zappalorti
(1975) found individuals in North Carolina active at all
times of the day when air temperatures were above
18 C but less than 30 C. Body temperatures ranged
from 18 to 24 C in basking turtles and from 24 to 28 C
in active turtles. In Delaware, Arndt (1977) reported
that the body temperature of turtles (N = 12) in the
field ranged from 17.0 to 35.0 C; 10 individuals found
sunning had temperatures that ranged from 24.0 to
35.0 C (X = 28.6). Ernst (1977) reported that active
bog turtles (N = 98) he found in Pennsylvania had
cloacal temperatures ranging from 16.2 to 31.0 C
(X = 20.2 ± 2.29). Those basking (N = 37) had the
highest temperatures, ranging from 22.0 to 31.0
(X = 25.3 ± 2.07). These data do not indicate that the
bog turtle is active at temperatures higher than those
reported for other species of freshwater turtles (Bratt-
strom 1965). Evidence provided by Ernst (1977) sug-
gests that basking elevates the body temperature—
which is the primary reason for basking in other
turtles (Boyer 1965; Moll and Legler 1971; Bury 1972;
Auth 1975). Ernst (1977) reported that bog turtles
avoid summer heat by burrowing into the soft sub-
strate of waterways, crawling under sedge tussocks, or
entering muskrat bank burrows.

Movements

Little is known about the spatial relations of the
species. One male studied in Pennsylvania moved only
an average of 12 m between three recapture sites in the
same month: when it was displaced 0.4 km away it
returned to the capture area in 1 day (Ernst and Bar-
bour 1972). This limited evidence suggests that the
turtle has homing ability. Zappalorti (1975) recaptured
three turtles 39-72 m from the place of first capture
after 1-5 weeks, which indicates that these turtles have
a small activity area.

Ernst (1977) calculated the mean home range of 19

Pennsylvania turtles to be 1.30 ± 0.39 ha— 1.33 ±
0.49 ha for 11 males and 1.26 ±0.30 ha for 8 females.
A. J. Barton [in Ernst 1977) found home ranges to be
0.008 to 0.121 ha for males and 0.086 to 0.943 ha for
females.

Behavior

Details of intraspecific competition, dominance
(subordination), aggregation, or other behavioral inter-
actions of the bog turtle are poorly known. Zappalorti
(1976) observed threats and attacks between males in
the wild and in captivity. Ernst (1977) found two or
more males aggregated together in the field, but he did
not observe any aggressive behavior.

Bog turtles frequent wet, soggy terrain also inhab-
ited by spotted turtles {Clemmys guttata) and wood
turtles (C. insculpta) in the northeastern States. In
deeper standing water are painted turtles (Chrysemys
picta), snapping turtles {Chelydra serpentina), mud
turtles (Kinosternon subrubrum), and stinkpots
(Sternotherus odoratus); and box turtles (Terrapene
Carolina) are nearby on land (Barton and Price 1955;
Nemuras 1966c; Ernst 1971, 1976). Ernst (1976)
reported that in Pennsylvania bog turtles sometimes
shared basking and feeding sites with spotted and
painted turtles, and that spotted and bog turtles occu-
pied the same muskrat burrows. The habits and
habitats of the spotted turtle are most similar to those
of the bog turtle, but no information exists on possible
competitive interactions where these two species are
sympatric.

Reproduction

Mating occurs from late April to early June and
nesting is in June, July, and occasionally August
(Barton and Price 1955; Campbell 1960; Nemuras
1967, 1976; Ernst and Barbour 1972; Zappalorti 1976).
Although females have been reported to remain
secluded during the breeding season (Cramer 1935;
Ernst and Barbour 1972; Nemuras 1976; Zappalorti
1975, 1976), recent studies by C. H. Ernst (personal
communication) indicate that females are as active as
males in the breeding season.

Zappalorti (1976) described courtship as occurring in
three phases: sexual recognition, aggressive biting,
and mounting. Males mount females by biting or
nipping at the female's neck and by hooking the claws
of all four feet to her shell (Cramer 1935; Barton and
Price 1955; Campbell 1960; Ernst and Barbour 1972;
Zappalorti 1976; Arndt 1977). Mating occurs both in
shallow water and on land (Barton and Price 1955;
Campbell 1960; Nemuras and Weaver 19746; Zappa-

lorti 1976). Nemuras (19746) observed turtles in south-
west Virginia mating during rainy weather.

Several workers who have described the nesting
habits of bog turtles (Barton and Price 1955; Nemuras
1965, 1967, 1974a; Eglis 1967; Zovickian 1971a, 19716;
Arndt 1972; Ernst and Barbour 1972; Nemuras and
Weaver 19746; Sachsse 1974; Zappalorti 1976), have
reported that females dig the nest in open and elevated
ground in areas with moss, grassy tussocks, or moist
earth. Clutch size varies from one to five eggs; the
normal complement is three to five. It is not known
whether more than one clutch of eggs is laid each year.

Incubation time in captivity ranges from 6 to 10
weeks, and mostly from 7 to 8 weeks (Campbell 1960;
Eglis 1967; Nemuras 1969; Nemuras and Weaver
19746; Zappalorti 1976; Arndt 1977; Tryon and
Hulsey 1977). Barton and Price (1955) reported a
hatchling emerging from a nest in early September
under natural conditions. Overwintering of eggs
deposited in late summer or fall is unconfirmed,
although expected. There is no parental care of the
young.

Growth and Sexual Maturity

Hatchling bog turtles are 25 to 30 mm long (Zovick-
ian 1971a, 19716; Arndt 1972; Nemuras 1974a;
Sachsse 1974). Arndt (1977) reported that 17 hatch-
lings in captivity were 24.4-26.2 mm long (X = 25.5). A
yearling in Pennsylvania was 38 mm long (Ernst and
Barbour 1972). In captivity, a turtle 2 years old and 53
mm long grew 31 mm in 2 years (Barton and Price
1955).

Ernst (1977) reported that Pennsylvania bog turtles
averaged 22.9 mm (range, 17.2-28.5 mm) in plastral
length as hatchlings. Growth closely resembled that of
the spotted turtle, in that there was a gradual reduc-
tion in growth rate with age. Further, he reported that
the bog turtle apparently has a slower growth rate
than the sympatric spotted turtle or painted turtle.

Female bog turtles may be sexually mature when 75
mm long and about 5 years old (Barton and Price
1955). For Pennsylvania bog turtles, Ernst (1977)
stated that sexual maturity is probably attained by
both sexes at a plastral length of 70 mm— a length
reached by some in the 6th year, but not by most until
the 8th year.

Population Dynamics

Natality, mortality, immigration, and emigration
rates of natural populations of bog turtles are
unknown.

Of 226 turtles reported in the literature, there were

93 males, 122 females, and 11 juveniles (Barton and
Price 1955; Nemuras 1965, 1967; Zappalorti 1975;
Ernst 1977; Arndt 1977). Data are insufficient to
enable one to estimate the reproductive span of adults
or the sex ratio of any population. In general, most
freshwater turtles have a sex ratio of 1:1, and are long-
lived (Bury 1979).

Density estimates vary from a low of 5 per ha where
commercial collectors sifted whole bogs, to an esti-
mated high of about 125 individuals per ha (Eglis
1967). The numbers found at seven North Carolina
bogs varied from 1 to 26 at each site (Zappalorti 1975).
In Maryland, Campbell (1960) located 21 turtles in a
swamp about 120 m long and 9 to 18 m wide (about
0.15 ha), which represents a density of about 140
turtles per ha.

At a Pennsylvania study area, the bog turtle repre-
sented only 0.8% of the turtles (10 of 1,218) captured
over a 3-year period (Ernst 1971). Zappalorti (1975) re-
ported collecting 54 bog turtles in seven North Caro-
lina bogs during 225 h of search (1 turtle per 4.2 h). In
Delaware, Arndt (1977) found 44 turtles during 81 h of
search (1 turtle per 1.8 h).

Predation

Nests, young, and adults of bog turtles are prey of
raccoons, skunks, dogs, foxes, and other large preda-
tors (Campbell 1960; Ernst and Barbour 1972; Nem-
uras 19746, 1976).

The bog turtle is relatively small and has a drab-
colored shell (often covered with mud); consequently,
when it is motionless it often is well concealed in
nature. It sometimes plunges or actively digs into the
mud substratum to escape (Cooper 1949; Barton and
Price 1955; Nemuras 1965, 1967; Ernst and Barbour
1972; Nemuras and Weaver 1974a, 19746). It some-
times uses the burrows and trails of muskrats and
meadow mice as travel routes and for cover (Bishop
1923; Arndt 1972; Ernst and Barbour 1972; Arndt
1977).

Responses to Habitat Change
and Collecting

Urbanization is a serious threat to the survival of
the bog turtle, particularly in the northeastern States.
In recent years, the species has apparently disap-
peared from Staten Island (Nemuras and Weaver
1974a; Zappalorti 1976).

Bog turtle sites have been destroyed by several
kinds of urban developments (Barton and Price 1955;
Robotham 1963; Nemuras 1965; Nemuras and Weaver
1974a), such as shopping centers, a golf course, a
sewage disposal plant, a city park, and a playground.

6

Road construction also has disrupted populations of
the turtle (Robotham 1963; Nemuras 1974a, 19746;
Nemuras and Weaver 19746) and mortality on high-
ways may be significant (Arndt 1977).

Habitat is destroyed by landfills and by the draining
of swampy areas to control mosquitoes or for indus-
trial development (Robotham 1963; Eglis 1967; Nem-
uras 1967, 1974a). Scrap-dumping activities and
mining at quarries have filled in parts of bogs inhab-
ited by the species (Campbell 1960; Nemuras 1965).
Drainage and development of deep bogs for muck
farming has eliminated habitat (Nemuras 1967). The
draining of soggy pastures (sometimes accompanied
by burning of sedge tussocks) and trenching through
bogs and marshes in dairy farm areas have also
greatly reduced the area of habitats for the bog turtle
(Nemuras 1966a, 19746; Nemuras and Weaver 19746;
Zappalorti 1976). Livestock grazing in pasture habi-
tats (tussock areas) could injure some turtles (Nem-
uras and Weaver 19746).

The invasion of marsh habitats by purple loosestrife
(Lythrum salicaria) has greatly altered the character of
many wetlands in New York (Smith 1964). The domi-
nance and persistence of this aggressive Eurasian
weed is possibly a threat to northern populations of
the bog turtle.

Wright (19186) stated that the species was vanish-
ing with the drying up or draining of sphagnum bogs
and "feather-bed" swamps. Ernst and Barbour (1972)
reported that the draining of the habitat has nearly
eliminated the species over most of its original range.
On the other hand, some populations have been
flooded when waters were impounded (Nemuras
1974a).

Collecting for the pet trade is a serious problem for
small, isolated colonies; unrestricted or illegal col-
lecting is encouraged by the commercial value of bog
turtles in Europe— $75-$150 apiece (Eglis 1967;
Salazar 1967; Nemuras 1969, 1974a, 19746, 1976;
Behler 1971; Weaver 1972; Campbell 1974; Zappalorti
1976; Arndt 1978). There is also a high demand for this
turtle in the United States due to its presumed rarity.
Clandestine collecting is a serious threat to natural
populations. Occasionally bog turtles are shot (Nem-
uras 19746; Nemuras and Weaver 19746).

Conservation and Management

Scientific and esthetic interest in the species is high.
It is the smallest of the four species of the genus
Clemmys, a North American group, and has a relictual
distribution. Collecting for scientific study has little
impact on the species; most current workers mark and
release animals at the site of capture.

The rarity or plight of the bog turtle has been dis-

cussed by many authors: Babcock (1917, 1919),
Wright (19186), Netting (1927), Cramer (1935), Dit-
mars (1936), Pope (1939), McCauley and Manseuti
(1943), McCauley (1945), Carr (1952), Barton and Price
(1955), Campbell (1960, 1974), Robotham (1963), Nem-
uras (1965, 1966a, 19666, 1966c, 1967, 1969, 1974a,
19746, 1976), Eglis (1967), Pritchard (1967), Salazar
(1967), Schwartz (1967), Behler (1970, 1971), Zovickian
(1971a, 19716), Arndt (1972, 1975), Ernst and Barbour
(1972), Weaver (1972), Anonymous (1973), Bloomer
and Bloomer (1973), Nemuras and Weaver (1974a,
19746), Sachsse (1974), Conant (1975), Harris (1975),
Zappalorti (1975, 1976), and Ernst and Bury (1977).
Ernst and Barbour (1972) reported that this species
has been considered as the rarest turtle in North
America for more than 50 years.

Tryon and Hulsey (1977) reported that bog turtles
bred and laid eggs in captivity. They contended that a
substantial captive-bred population is essential to alle-
viate the effects of disasters to natural populations
and habitats. I contend that these efforts are unlikely
to succeed in producing surplus animals for restock-
ing. Further, it is important that captive breeding
avoid mixing native stocks, lest genetic differences be
lost.

Conservation efforts should focus on natural popu-
lations to reveal the present abundance of the species
and the prime habitat areas that need to be protected.
The bog turtle seems to be present in many disjunct
wetlands. Nemuras (1975) found about 260 localities
for the turtle; most (59%) were in New Jersey and
Pennsylvania. Several new localities are known in
North Carolina (Zappalorti 1975) and recent studies by
the State of Maryland (Anonymous 1978) indicated
that the turtle occurred at 130 sites in three counties.
Arndt (1978) proposed that the bog turtle is not rare,
but rather is secretive, and that lack of previous in-
terest and effort to find it was the reason for its
"rarity." There is encouraging evidence that the bog
turtle is not depleted in all parts of its range. Still, its
wetland habitat is in danger of being altered by man's
activities and many populations are near expanding
urban and industrial areas in the northeastern United
States.

The bog turtle now has some protection in New
York, Connecticut, Pennsylvania, New Jersey, and
Maryland (Weaver 1972; McCoy 1974; Nemuras and
Weaver 1974a), and is a species of special concern in
North Carolina. Private reserves for the turtle have
been set aside in New Jersey (Nemuras and Weaver
1974a, 19746), and one area is being considered by
New York for a reserve, principally for the bog turtle.
The Pennsylvania Game Commission manages two
bog turtle reserves: Middle Creek Wildlife Manage-
ment Area, Lebanon County, and Pymatuning Wild-

life Management Area, Crawford County. A few bog
turtle populations occur on U.S. Forest Service lands
in North Carolina, where the turtles are in no imme-
diate danger unless roads are constructed in the
habitat (Zappalorti 1975) or the bog areas are dis-
rupted.

The species is included in the Red Book (U.S.
Department of the Interior 1973), but it is not offi-
cially listed as an endangered or threatened species
under the Endangered Species Act of 1973. The bog
turtle is on Appendix II of the International Con-
vention of Trade in Endangered Species of Wild Fauna
and Flora; an export permit is required before the
animal may be sent out of the United States.

Discussion

The bog turtle apparently is uncommon over much
of its range. It is a secretive animal and many popu-
lations may not be found without special effort. Some
populations have been destroyed by man's activities.
The location and size of other populations have not
been reported for fear that they would be raided by
collectors.

The biology of the turtle remains poorly known.
Only four substantive studies on the ecology of this
species have been published (Barton and Price 1955;
Ernst 1977; Zappalorti 1976; Arndt 1977), and not all
aspects of its ecology have been considered. Further
research is needed to determine its habitat require-
ments and adaptive strategies throughout its range.
Also, the species has many reproductively isolated
populations and geographic variation in this species
should be examined.

More literature has been published on the plight of
the bog turtle than on that of any other North Amer-
ican freshwater turtle. Most of the authors have con-
cluded that protection of the species is necessary
because of its rarity, spotty distribution, specialized
habitat requirements, and unique appeal. Habitat loss
appears to be the most serious problem for remaining
populations. Irresponsible collecting also threatens
remaining populations.

I believe that an objective review of the present
distribution and abundance of the bog turtle in each
State within its range is warranted. I suggest that the
most critical need is to determine the amount of
habitat and size of the populations that remain, and
then, if necessary, to consider it as a threatened
species under the Endangered Species Act.

Acknowledgments

I thank K. T. Nemuras, J. A. Weaver, and R. T.
Zappalorti for providing distributional and bib-

liographic information. C. H. Ernst, C. J. McCoy, and
G. R. Zug offered helpful comments on earlier versions
of this report.

References

Anonymous. 1973. Endangered amphibians and reptiles of

Maryland: a special report. Bull. Md. Herpetol. Soc. 9(3):42-

100.
Anonymous. 1978. Eagle, fox squirrel top Maryland's Endan-
gered Species agenda. Endangered Species Tech. Bull.

3(2):4-6.
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