Trachemys scripta

A small turtle, with carapace length of up to 300 mm. Carapace moderately depressed, slightly elongate, smooth, with a weak mid-dorsal ridge; posterior edge with moderate indentations. Plastron flat. Head moderate, snout elongate. All limbs with 5 claws, partly webbed. Males smaller than females, with long claws on fore-limb and longer tail. Color of carapace and dorsal sides of limbs and head dark green with numerous yellow stripes; a short, broad, red stripe behind each eye. Ventral sides yellow, with a pattern of dark green lines and spots.

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).

Biogeographic Regions: nearctic (Native ); neotropical (Native )

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.

Biogeographic Regions: nearctic (Native ); neotropical (Native )

According to Saleh (1997) individuals belonging to this species were observed and collected between 1992 and 1997 in the Nile at the Barrages north of Cairo and at Maadi, and in canals in the Giza area. He states that "The species appears to have become locally established at least in the vicinity of Cairo."  This author failed to observe any examples of the species during brief searches at the foregoing locations. It is at least certain that the species is by no means common. It is possible that some of Saleh's (1997) records concerned released individuals that had not become established yet, and do not represent a locally naturalized population. It is perhaps unlikely that this species could become well established, given intensive human utilization of suitable habitats. T. s. elegans is commonly traded in Egypt.

Natural range is in eastern North America. A popular pet, introduced to many parts of the world. In the Middle East also in Bahrain and Israel.

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Exotic

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (200,000 to >2,500,000 square km (about 80,000 to >1,000,000 square miles)) The range extends from Michigan to Argentina, and from the Atlantic coast to New Mexico; it also includes southern Baja California (at least formerly). The species has been introduced and is established in many areas outside the native range, including Florida (Schwartz and Henderson 1991; Ashton and Ashton 1991; Hutchison, 1992, Herpetol. Rev. 23:74-75; Townsend et al., 2002, Herpetol. Rev. 33:75; Ehret and Parker, 2005, Hepretol. Rev. 36:78), Guam (McCoid, 1992, Herpetol. Rev. 23:26), New York (Klemens 1993), and New Mexico (Stuart, 1995, Herpetological Review 26:107). It has been found in California (e.g., Stitt et al., 2004, Herpetol. Rev. 35:187) and Hawaii (McKeown 1996), but establishment is uncertain.

Continent: Middle-America South-America North-America Asia Europe Caribbean Africa
Distribution: scripta: USA (Alabama, Florida, Georgia, North Carolina, South Carolina, Virginia) [Rhodin et al. 2010]  elegans: Mexico (Nuevo Leon, Tamaulipas), USA (Alabama, Arkansas, Florida, Georgia, Illinois, Indiana, Iowa,Kansas, Kentucky, Louisiana, Mississippi, Missouri,Nebraska, New Mexico [eastern], Ohio, Oklahoma,Tennessee, Texas, West Virginia); Introduced to Australia (New South Wales, Queensland,Victoria), Austria, Bahamas, Bahrain, Belgium,Bermuda, Brazil, British Virgin Islands, Cambodia,Canada (Ontario), Cayman Islands, Chile, China(Hong Kong), Colombia, Cyprus, Czech Republic,Denmark, Dominican Republic, Ecuador, Egypt,France, French Polynesia, Germany, Great Britain,Greece, Guadeloupe, Guam, Guyana, Honduras,Hungary, Indonesia (Java, Kalimantan, Papua,Sulawesi, Sumatra), Ireland, Israel, Italy, Japan(mainland, Ryukyu Archipelago), Malaysia (East,West), Martinique, Micronesia, Myanmar, Nether-lands, Netherlands Antilles, New Zealand, NorthernMariana Islands [Saipan], Palau, Panama, Philippines(Cebu, Luzon, Mindanao), Poland, Portugal, PuertoRico, Réunion, Russia, Saudi Arabia, Seychelles(Mahé), Singapore, Sint Maarten, Slovakia, Slovenia,South Africa, South Korea, Spain (Balearic Islands,Continental), Sri Lanka, Sweden, Switzerland, Tai-wan, Thailand, Trinidad, USA (Arizona, California,Colorado, Connecticut, Delaware, Florida, Hawaii,Maine, Maryland, Massachusetts, Michigan, NewJersey, New Mexico [western], New York, NorthCarolina, Ohio, Oregon, Pennsylvania, SouthCarolina, Virginia, Washington), US Virgin Islands,Vietnam, Japan, Philippine Islands  troosti: USA (NC Tennessee, SE Kentucky, SW Virginia, NW Georgia, NE Alabama);
Type locality: Cumberland River (probaby Tennessee).  USA (Nebraska [HR 30: 108], introduced to Hawaii fide McKeown); Mexico (Baja California, Yucatan, Nuevo Leon), Guatemala, Belize, Honduras, El Salvador, Nicaragua, Costa Rica, Panama, Brazil, Colombia, Venezuela, Chile, Thailand, Singapore, W Malaysia and other parts of Indochina [introduced; fide COX et al. 1998]  Gambia (introduced)  Introduced to the French West Indies (Grande-Terre, Basse-Terre) [Schwartz & Thomas 1975)  Italy (introduced to Sardinia) Spain (introduced fide MALKMUS 2006) France (introduced fide Berroneau et al. 2010) Greece (introduced and breeding on the island of Kos [BRUEKERS et al. 2006], Cyprus [BAIER et al. 2009])

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.

Range length: 12.5 to 28.9 cm.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism: female larger; sexes shaped differently

Average mass: 240 g.

Average basal metabolic rate: 0.1157 W.

There are actually three regional subspecies of pond slider in North America. One subspecies is called the red-eared slider. They get their name from the broad reddish or orange stripe behind each eye, though some red-eared sliders do not have this stripe. Young hatchlings have a green carapace (upper part of their shell) and skin with yellow green to dark green markings and stripes. Carapace color in adults fades to a muted olive green color. Some older individuals (especially males) become very dark, appearing almost black with few visible markings. The carapace is oval and flattened with a weak center ridge (keel). The plastron (the underpart of the shell that covers the belly) is yellow with dark markings in the center of each scute (part of the plastron).

The yellow-bellied slider is another kind of pond slider, they have a yellow blotch behind each eye which may join the neck stripe, but is usually only seen in young 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.

Cumberland turtles are the third kind of pond slider. They have a narrower orange-yellow stripe behind each eye and have fewer and much wider stripes on the legs, neck, and head. All pond slider subspecies have webbed feet that aid in swimming. Males are usually smaller than females, but have a much longer, thicker tail. Males have long claws that they use in courtship and mating. They range in total length from 12.5 to 28.9 cm.

Range length: 12.5 to 28.9 cm.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism: female larger; sexes shaped differently

Average mass: 240 g.

Average basal metabolic rate: 0.1157 W.

Length: 29 cm

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).

Habitat Regions: temperate ; freshwater

Aquatic Biomes: lakes and ponds; rivers and streams

Wetlands: marsh ; swamp

Other Habitat Features: riparian

Pond sliders prefer quiet, muddy bottomed, permanent waters with good places to sit in the sun (places to bask) and plentiful aquatic vegetation. They are usually found only in a single area except when they go onto land to nest or when they burrow into the lake or river bottom to hibernate.

Habitat Regions: temperate ; freshwater

Aquatic Biomes: lakes and ponds; rivers and streams

Wetlands: marsh ; swamp

Other Habitat Features: riparian

Habitat and Ecology

Systems

• Terrestrial
• Freshwater

Freshwater habitats including rivers, canals, and ponds.

Comments: Usually in quiet water with abundant aquatic vegetation, soft bottom, and basking sites. Hibernates underwater or in protected places near waterline (Ernst and Barbour 1972). More tolerant of pollution than are most turtles. Eggs are laid in nests dug in soft damp soil in open areas. Nesting area may be on nearest suitable site or far from water (usually the former) (Ernst and Barbour 1972). In Costa Rica, some females briefly enter the sea and nest on Caribbean Sea beaches (upper beach berm usually under cocoplum vegetation; hatchlings probably do not enter the sea (Moll 1994).

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Rarely may migrate 350 m or more between water and nest site (see Ernst and Barbour 1972). Female exhibit strong fidelity to previously used nesting area (Tucker 2001).

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).

Animal Foods: amphibians; fish; insects; mollusks; aquatic crustaceans

Plant Foods: leaves; macroalgae

Primary Diet: omnivore

Comments: Adults feed opportunistically on various plants and animals. Juveniles eat mainly small aquatic animals. In Louisiana, plant material became more frequent in diet with increasing turtle size (Hart 1983).

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.

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.

Known Predators:

• raccoons (Procyon lotor)
• striped skunks (Mephitis mephitis)
• Virginia opossums (Didelphis virginiana)
• red foxes (Vulpes vulpes)

Anti-predator Adaptations: cryptic

Trachemys scripta is prey of:
Didelphis virginiana
Mephitis mephitis
Procyon lotor
Vulpes vulpes

This list may not be complete but is based on published studies.

Trachemys scripta preys on:
non-insect arthropods

This list may not be complete but is based on published studies.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: > 300

>1,000,000 individuals

Most of 1006 turtles marked and released in Illinois were recaptured within 0.8 km of release point (see Ernst and Barbour 1972). Movements exceeding 2 km are known. In South Carolina, a metapopulation encompassed habitats 3.5 km from a core area (10-ha wetland) (Burke et al. 1995).

Some populations exhibit significantly faster growth rate and larger adult body size than others.

Nest survivorship in Panama was 0.03. In South Carolina, annual first-year survivorship (from egg laying) averaged 0.11 (range 0.01-0.28) over 5 years; annual survivorship was 0.84 for adult males, 0.77 for adult females (Frazer et al. 1990).

Pond sliders communicate with touch and vibrations. They also have a good sense of vision.

Communication Channels: tactile

Other Communication Modes: vibrations

Perception Channels: visual ; tactile ; acoustic ; vibrations ; chemical

Pond sliders communicate with touch and vibrations. They also have a good sense of vision.

Communication Channels: tactile

Other Communication Modes: vibrations

Perception Channels: visual ; tactile ; acoustic ; vibrations ; chemical

Aquatic and diurnal turtle.

Comments: Primarily diurnal. Generally inactive in winter in north but mild weather may stimulate emergence (Ernst and Barbour 1972).

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.

Development - Life Cycle: temperature sex determination

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.

Development - Life Cycle: temperature sex determination

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.

Range lifespan
Status: wild: 42 (high) years.

Typical lifespan
Status: wild: 30 (high) years.

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.

Range lifespan
Status: wild: 42 (high) years.

Typical lifespan
Status: wild: 30 (high) years.

Maximum longevity: 41.3 years (captivity) Observations: In the wild these animals live up to 30 years. Studies in the wild failed to find any increase in mortality with age (Castanet 1994).

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.

Mating System: polygynous

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.

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.

Range number of offspring: 4 to 23.

Range gestation period: 85 (high) days.

Range age at sexual or reproductive maturity (female): 5 to 7 years.

Range age at sexual or reproductive maturity (male): 3 to 5 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous

Average number of offspring: 13.

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.

Parental Investment: no parental involvement; pre-fertilization (Protecting: Female); pre-hatching/birth (Protecting: Female)

Male pond sliders approach females during the mating season, between March and July and perform a courtship dance. They face a female, stretch out their front feet, and vibrate their long claws on the female's head and neck. If receptive the female will sink to the bottom of the pond for mating.

Mating System: polygynous

Most nesting occurs from May to July. Females will often travel some distance to find a suitable nesting site. Nests are dug in the soil with the female's back feet. Females lay from 4 to 23 eggs in the 2-4 inch deep hole and then cover the eggs with soil. It takes 2 to 2.5 months for young to hatch. They do so using their "egg tooth" (caruncle), a sharp feature on their nose that helps them cut open the leathery shell of the egg. The caruncle disappears soon after hatching. Hatching occurs between July and September. If hatching occurs in the late fall, the young may stay in the nest all winter and emerge the following spring. Red-eared sliders grow quickly at first, reaching about 2 inches within the first year, but growth slows as they get older.

Males become adults at 3 to 5 years of age, when they are about 4 inches long; females become adults at 5 to 7 years old, when they are 6 to 7.5 inches in length.

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.

Range number of offspring: 4 to 23.

Range gestation period: 85 (high) days.

Range age at sexual or reproductive maturity (female): 5 to 7 years.

Range age at sexual or reproductive maturity (male): 3 to 5 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous

Average number of offspring: 13.

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.

Parental Investment: no parental involvement; pre-fertilization (Protecting: Female); pre-hatching/birth (Protecting: Female)

In the U.S., eggs are laid from mid-March to August, with the earliest nesting occurring in the southern states. Nests from January to March near Tortuguero, Costa Rica (Moll 1994). In South Carolina, mean clutch size was 6.3 (range 1-6); nesting females produced an average of 1.1 clutches/year (usually 1 clutch, rarely as many as 3); successive clutches generally were separated by an interval of about 1 month; females matured at age 7 years (Frazer et al. 1990). In Illinois, females produced an estimated 2-3 clutches per year, and most adult females evidently nested in successive years (Tucker 2001). In the U.S., eggs hatch in summer or early fall; hatchlings may commonly overwinter in nest (Jackson 1994). In Costa Rica, hatchlings from sea beach nests emerged by May and June (Moll 1994). In South Carolina, the mean proportion of adult females nesting in any given year was 0.37 (Frazer et al. 1990). See Tucker et al. (1995, Herpetologica 51:354-358) for information on annual variation in individual growth rates.

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.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: lower risk - near threatened

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

History

• 1996
  Lower Risk/near threatened
  (Baillie and Groombridge 1996)

Population, if at all established, seems very small. An alien species, with no conservation importance in Egypt. Its impact on other biological components in the local envi­ronment should be monitored.

Least Concern

Canada

Rounded National Status Rank: NNA - Not Applicable

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Intrinsic Vulnerability: Highly to moderately vulnerable.

Population

Population Trend

Degree of Threat: Medium

Major Threats

Conservation Actions

Global Protection: Very many (>40) occurrences appropriately protected and managed

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.

Negative Impacts: injures humans (carries human disease)

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.

Positive Impacts: pet trade ; food

Comments: In the early 1990s, hundreds of thousands were being exported annually to Europe to supply the pet trade.

Species Impact: Introduced populations in Europe may be having a negative impact on populations of native turtle species (Simons, 1994, New York Times, 5 July, p. C4).