Download Trachemys scripta common slider

Trachemys scripta
common slider
(Also: pond slider)
By Tanya Dewey
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Testudines
Family: Emydidae
Genus: Trachemys
Species: Trachemys scripta
Geographic Range
Pond sliders are native to the Nearctic and Neotropical regions. They are found from the
southern Great Lakes region east to West Virginia, west to Indiana and Illinois and
south throughout most of the southeastern and south-central United States. The range of
pond sliders continues through Mexico and Central America to Venezuela in South
America. Subspecies in the United states include Trachemys scripta elegans, native to
the Mississippi river valley, from Illinois, west to Kansas and Oklahoma, and south to
the Gulf of Mexico, T. s. scripta, found from Virginia to northern Florida and Alabama,
and T. s. troostii, found from eastern Kentucky to Georgia and Alabama (Conant and
Collins 1991). (Conant and Collins, 1991; Harding, 1997)
Habitat
Pond sliders prefer quiet, soft, muddy bottomed waters with suitable basking spots.
They are faithful to their home ranges, leaving only to nest or hibernate (Dawson 1998).
(Dawson, 1998)
Physical Description
Mass
240 g (average)
(8.45 oz)
Length
12.50 to 28.90 cm
(4.92 to 11.38 in)
Basal Metabolic Rate
There are three subspecies of pond slider in the United States. Trachemys scripta
elegans (red-eared slider) gets its name from the broad reddish or orange stripe behind
each eye, though some red-eared sliders do not have this streak. Young hatchlings have
a green carapace and skin with yellow green to dark green markings and stripes. Color
in adults fades to a muted olive green color. Some older individuals (especially males)
become melanistic, appearing almost black with few visible markings. The carapace is
oval and flattened with a weak keel. The plastron is yellow with dark markings in the
center of each scute. Trachemys scripta scripta (yellow-bellied slider) has a yellow
blotch behind each eye which may join the neck stripe, but is usually only evident in
juveniles and females. Yellow vertical bands mark the carapace, with the underside
being yellow with smudges. The plastron is also yellow with dark blotches or smudges.
Trachemys scripta troostii (Cumberland turtle) has a narrower orange-yellow stripe
behind each eye. It is similar to T. s. elegans, but has fewer and much wider stripes on
the legs, neck and head. All the subspecies have webbed feet that aid the turtle in
swimming. There is some sexual dimorphism. The male is usually smaller than the
female with a much longer, thicker tail. The cloacal opening of the male is beyond the
edge of the carapace while the female's opening is usually at or under the rear edge of
the carapace. Males have elongated claws that they use in courtship/mating. They range
in total length from 12.5 to 28.9 cm. (Conant and Collins, 1991; Dawson, 1998)
Development
Pond slider eggs that are incubated at temperatures between 22 and 27 degrees Celsius
become only males, while eggs that are incubated at warmer temperatures become
females. Baby sliders come out of the egg looking like small adults. (Harding, 1997)
Reproduction
Breeding interval
A female may have 1 to 3 clutches in a season, with second clutches laid in July or
August.
Breeding season
Breeding occurs from March through July.
Number of offspring
4 to 23
Gestation period
85 days (high)
Age at sexual or reproductive maturity (female)
5 to 7 years
Age at sexual or reproductive maturity (male)
3 to 5 years
Male pond sliders have a unique courtship dance that they engage in anywhere between
the months of March and July. Males will approach a female from the front, stretch out
their front feet and vibrate their long claws on the female's head and neck. Some may
even bite the female. The female usually continues to swim forward while the male does
this and, if receptive, will eventually stop and sink to the bottom. The male will then
grip the female's carapace with all four claws and arrange himself on top of her. He will
then bend his tail under hers, let go of his front arms, and take an almost vertical
position. From this position mating occurs, and lasts about 15 minutes. (Dawson, 1998)
Maturity occurs in males at 3 to 5 years of age, when they are about 4 inches long;
females at 5 to 7 years and 6 to 7.5 inches in length (Dawson 1998). Most nesting
occurs from May to July. A female may have 1 to 3 clutches in a season, with second
clutches laid in July or August. Females will often travel some distance to find a
suitable nesting site. Nests are dug in the soil with the female's back feet. Four to 23
eggs are laid in the 2 to 4 inch deep hole and then covered with the displaced soil. It
takes 2 to 2.5 months for young to hatch and they do so using their "egg tooth"
(caruncle) which disappears soon after hatching. Hatching occurs between July and
September. If hatching occurs in the late fall, the young may overwinter in the nest and
emerge the following spring. Pond sliders grow quickly at first, reaching about 2 inches
within the first year, but growth slows as they get older. (Dawson, 1998; Harding, 1997;
Smither, 1998)
Female pond sliders choose safe nesting sites for their eggs. Once they lay the eggs they
leave the nest and there is no further parental care. (Harding, 1997)
Lifespan/Longevity
Extreme lifespan (wild)
42 years (high)
Typical lifespan (wild)
Like most turtles, pond sliders can live for a long time. They have been known to live
for 42 years in the wild, though most don't live past 30 years. Most red-eared sliders
probably die when they are hatchlings. From 7 to 10 out of every 10 eggs and hatchlings
will die before their first year. (Harding, 1997)
Behavior
Pond sliders enjoy basking on logs, rocks, or stumps near the water. Pond sliders are
often observed in large groups mainly because of their aggregation on limited numbers
of basking sites. Sometimes you can see sliders stacked on top of each other three high.
The name "slider" refers to the quick retreat from their basking site into the water when
they feel even the slightest bit threatened. Sliders will sleep at night underwater, usually
resting on the bottom or floating on the surface, using their inflated throat as a flotation
aid. Sliders become inactive at temperatures below 10°C. They will often hibernate
underwater or under banks and hollow stumps. Emergence occurs in early March to late
April. (Dawson, 1998; Harding, 1997; Smither, 1998)
Communication and Perception
Pond sliders communicate with touch and vibrations. They also have a good sense of
vision.
Food Habits
Young pond sliders tend to be more carnivorous than adults, eating about 70% animal
matter and 30% plant matter. Adults eat 90% plant matter and 10% animal matter
(Wilke 1979). Foods include aquatic insects, snails, tadpoles, crawfish, fish,
crustaceans, and mollusks. They also eat plants like arrowhead, water lilies, hyacinths,
and duck weed. Feeding occurs under water, usually in the early morning or late
afternoon (Smither 1998). (Harding, 1997; Smither, 1998; Wilke, 1979)
Predation
Known predators

raccoons (Procyon lotor)

striped skunks (Mephitis mephitis)

Virginia opossums (Didelphis virginiana)

red foxes (Vulpes vulpes)
Pond slider eggs and hatchlings are preyed on by raccoons, skunks, opossums, foxes,
and other predators. They are relatively safe from most predators once they reach adult
size and while they are in the water. Large predatory fish seem to find the hatchlings
difficult to handle and do not tend to eat them. Red-eared sliders may attempt to bite
and scratch when harassed, but most pull their head and legs into their shells for
protection. (Harding, 1997)
Ecosystem Roles
Pond sliders help to control populations of the animals that they consume and affect
aquatic vegetation as they graze. Young pond sliders are an important food source for
large, aquatic predators.
Economic Importance for Humans: Negative
The establishment of this species outside its natural range (see comments below) may
be harmful to native turtle species, but evidence for this supposed competition is
presently lacking or anecdotal.
Wild slider turtles in natural habitats are essentially harmless to human interests. When
kept captive under unsanitary or stressful conditions or when fed contaminated
foodstuffs, this species can become a carrier of certain strains of Salmonella bacteria
capable of causing illness in humans.
Ways that these animals might be a problem for humans:
injures humans (carries human disease).
Economic Importance for Humans: Positive
Pond sliders fill an important niche in their wetland habitats, and are appealing to most
people. Pond sliders have unfortunately been heavily exploited by humans for both the
commercial pet trade and for food purposes.
Conservation Status
IUCN Red List:
Lower Risk - Near Threatened.
US Federal List:
No special status.
CITES:
No special status.
Pond sliders, especially red-eared sliders (T. s. elegans), have been heavily collected for
the pet trade and are sold by the millions in pet shops across the world. Because of
unsanitary conditions and a lack of knowledge on turtle care, few survive for long in
captivity. U.S. government regulations now require turtles to be at least 4 inches in
length before they can be sold as pets in the USA. However, many hatchlings are still
produced commercially for export to Europe, Mexico, and Japan where they are popular
as pets (Smither 1998). [Commercial turtle farms rarely qualify as "closed systems," and
farm breeding stock is often augmented by the capture of wild turtles.] In recent years,
numbers of adult sliders and related turtle species have been trapped for the food trade;
many have been exported to Asia. Native slider populations are declining due to habitat
destruction and pollution as well as overharvest. However, because of the release of
unwanted pets, sliders have established populations outside of their native range. They
have been found in California, France, South Africa, Bahrain, Japan, South Korea,
Guam, and Thailand. These introduced populations may have some effect on native
fauna and species, but to date there is little evidence supporting this. The biggest threat
to sliders is Man. Not only are they exploited for the pet and food trade, but slider eggs
are also used as fish bait. Sliders are often killed on roads by automobiles, and are
sometimes persecuted by fishermen who mistakenly consider the turtles to be fish
eaters. (Harding, 1997; Smither, 1998)
Other Comments
There are many named subspecies of Trachemys scripta. These include: T. s. scripta, T.
s. cataspila, T. s. callirostris, T. s. chichiriviche, T. s. elegans, T. s. emolli, T. s. grayi, T.
s. grayi, T. s. hartwegi, T. s. hiltoni, T. s. ornata, T. s. taylori, T. s. troostii, T. s. venusta,
T. s. nebulosa, T. s. ornata, T. s. yaquia, and T. s. gaigeae (sometimes considered a full
species, Trachemys gaigeae) (Ernst and Barbour 1989).
Some species & subspecies have had several names in the past which change as more
information is found. The following are a few of these previous names.
Pond slider:
1792 Testudo scripta
1831 Emys vittata
1889 Chrysemys scripta
1899 Pseudemys scripta
Present Trachemys scripta
Yellow-bellied slider
1802 Testudo serrata
1937 Pseudemys scripta scripta
1986 Trachemys scripta scripta
Red-eared slider
1839 Emys elegans
1844 Emys holbrooki
1855 Emys sanguinolenta
1873 Trachemys lineata
1889 Chrysemys scripta var. elegans
1944 Pseudemys scripta elegans
1986 Trachemys scripta elegans
Cumberland slider
1836 Emys troosti
1840 Emys cumberlandensis
1889 Chrysemys troostii
1937 Pseudemys scripta troostii
1986 Trachemys scripta troostii
(EMBL 1999) ("The EMBL Reptile Database", Oct. 1999; Ernst and Barbour, 1989)
Contributors
Tanya Dewey (author), Animal Diversity Web, University of Michigan Museum of
Zoology.
Trudy Kuhrt (author), Michigan State University.
James Harding
(editor), Michigan State University.
References
Oct. 1999. "The EMBL Reptile Database" (On-line). Accessed (Date Unknown) at
http://www.embl-heidelberg.de/.
Conant, R., J. Collins. 1991. Peterson Field Guides: Reptiles and Amphibians of
Eastern/Central North America. Boston: Houghton Mifflin Co..
Dawson, J. 1998. Accessed (Date Unknown) at
http://www.geocities.com/Heartland/Plains/3550/slider01.html.
Ernst, C., R. Barbour. 1989. Turtles of the World. Washington, D.C.: Smithsonian Inst.
Press.
Harding, J. 1997. Amphibians and Reptiles of the Great Lakes Region. Michigan:
University of Michigan Press.
Smither, B. 1998. "Gulf Coast Turtle & Tortoise Society" (On-line). Accessed (Date
Unknown) at
http://www.gctts.org/care_sheets/red_eared_turtle/red.eared.turtle2.html.
Wilke, H. 1979. Turtles. Munich, West Germany: Grafe & Unzer GmbH.
2009/03/08 10:29:59.544 GMT-4
To cite this page: Dewey, T. and T. Kuhrt. 2002. "Trachemys scripta" (On-line), Animal
Diversity Web. Accessed March 09, 2009 at
http://animaldiversity.ummz.umich.edu/site/accounts/information/Trachemys_scripta.ht
ml.