Painted Turtle
Painted turtle
Conservation status
Least Concern  (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Testudines
Family:	Emydidae
Subfamily:	Deirochelyinae
Genus:	Chrysemys Gray, 1844
Species:	C. picta
Binomial name
Chrysemys picta (Schneider, 1783)
Subspecies
C. p. bellii C. p. dorsalis C. p. marginata C. p. picta
Synonyms
Species and subspecies synonymy[1] Species Testudo picta Schneider, 1783 Subspecies C. p. bellii Emys bellii Gray, 1831 Emys oregoniensis Harlan, 1837 Chrysemys nuttallii Agassiz, 1857 Chrysemys pulchra Gray, 1873 Chrysemys cinerea var. bellii Boulenger, 1889 Chrysemys treleasei Hurter, 1911 Chrysemys picta bellii Bishop & Schmidt, 1931 C. p. dorsalis Chrysemys dorsalis Agassiz, 1857 Chrysemys cinerea var. dorsalis Boulenger, 1889 C. p. marginata Chrysemys marginata Agassiz, 1857 C. p. picta Testudo cinerea Bonnaterre, 1789 Chrysemys cinerea Boulenger, 1889

The painted turtle (Chrysemys picta) is the only species of Chrysemys, a genus of freshwater turtles in the family Emydidae. It lives in slow-moving waters, from southern Canada to Louisiana and northern Mexico, and from the Atlantic to the Pacific. Fossils show that the painted turtle existed 15 million years ago, but four regionally based subspecies (the eastern, midland, southern and western) evolved around the last Ice Age. The painted turtle is 10–26 cm (4–10 in) long and weighs 300–500 g (11–18 oz); females are larger than males. Its shell is smooth, oval, and flat-bottomed. Its skin is olive to black with distinctive red, orange, or yellow stripes on its extremities.

Reliant for warmth on its surroundings, the painted turtle is active only during the day, when it can often be seen basking for hours on logs or rocks. In winter, the turtle hibernates, usually in the mud of water bottoms. Mating occurs in spring and fall. Females dig nests and lay their eggs onshore from late spring to mid-summer. Hatched turtles grow until sexual maturity at 2-9 years for males and 6-16 years for females. Adults in the wild may live for over 40 years.The turtle eats aquatic vegetation, algae, and small water creatures including insects, crustaceans, and fish. The raccoon is its main predator, but it is also preyed upon by snakes, alligators, rodents, and birds of prey.

Wetland conversion and roadkill have lowered painted turtle population density from pre-modern times. However, its ability to change waterways, sometimes in dramatic groups of hundreds, and to live in disturbed settings, has helped it remain the most numerous turtle of North America. Only in parts of the Pacific Northwest is the painted turtle in danger of losing range: officially imperiled in Oregon and endangered in coastal British Columbia.

The painted turtle is the U.S.'s second most popular pet turtle, with most localities allowing both keeping and capture. In the traditional tales of Algonquian tribes, the colorful turtle played the part of a trickster. Now, the turtle is the official reptile of four U.S. states. In British Columbia, the species is popular, with several named businesses touting the turtle's "laidback lifestyle", yet turtles in the province are down to their last few thousand.

Taxonomy

The painted turtle (C. picta) is the only species of genus Chrysemys although it was originally described in 1783 by Johann Gottlob Schneider as Testudo picta.^[1] Over the years, biologists have debated the taxonomic classification of Chrysemys, Pseudemys (cooters), and Trachemys (sliders). As of 1952, many biologists combined Pseudemys with Chrysemys based on similar appearance.^[2] In 1964, based on measurements of skull and feet, the three genera were merged into one, but further measurements made in 1967 contradicted the earlier results. The same year, J. Alan Holman pointed out that, although the three turtles were often found together in nature and had similar mating patterns, they did not crossbreed. In the 1980s, studies of turtles' cell structure, biochemistry, and parasites further indicated that Chrysemys, Pseudemys, and Trachemys should remain separate.^[3]

The four subspecies of the painted turtle are eastern (C. p. picta), midland (C.p. marginata), southern (C. p. dorsalis), and western (C. p. bellii).^[4] The subspecies likely evolved in response to partial geographic isolation during the last ice age: about 100,000 years ago.^[5] At that time, painted turtles were divided into three different populations: eastern painted turtles along the southeastern Atlantic coast; southern painted turtles around the southern Mississippi River; and western painted turtles in the southwestern United States.^[6] Because the populations were never completely isolated, wholely different species never evolved. When the glaciars retreated about 11,000 years ago, all three subspecies moved northward. The western and southern subspecies met in Missouri and hybridized to produce the midland painted turtles, which then settled the Tennessee River basin, across the Mississippi.^[6] In 2003, David E. Starkey and coworkers classified the southern painted turtle as a separate species: C. dorsalis, but this is largely unrecognized because successful breeding between all subspecies is documented where they overlap.^[7]

The painted turtle's genus name comes from Greek for "gold" (chryso) and "freshwater tortoise" (emys), while the species name comes from Latin for "colored" (pictus).^[8] Marginati comes from the Latin for border and refers to the red markings on the outer (marginal) part of the upper shell. Dorsalis is the Latin for back, referring to the prominent dorsal stripe. Bellii honors zoologist Thomas Bell, a collaborator of Charles Darwin.^[9] An alternate common name for the painted turtle is skilpot from the Dutch for tortoise or sea turtle, schildpad.^[10]

Description

The painted turtle's shell is 10–26 cm (4–10 in) long^[11] and is oval, smooth, and flat-bottomed.^[12][13] The top shell color varies from olive to black so as to blend in with the streambed or lakebottom.^[14] The bottom shell is yellow, sometimes with dark markings in the center.^[15] The turtle's skin is also olive to black. The neck, legs, and tail have red and yellow stripes. The face has only yellow stripes.^[11][13] Behind each eye is a large, yellow spot and streak. The chin has two wide yellow stripes that meet at the tip of the jaw.^[14]

The upper jaw is an inverted "V", with a downward-facing, tooth-like projection on each side.^[16]

Compared to the adult, the hatchling has a proportionally smaller head, eyes, and tail, and is more vibrantly colored.^[17] Its shell is also more circular.^[18] Compared to the male, the female painted turtle is larger overall, but with a shorter, thinner tail, and shorter foreclaws.^[11][12][13] Females weigh 500 g (18 oz), while males weigh 300 g (11 oz).^[19]

The painted turtle's DNA is arranged in 50 chromosomes.^[13]

Although the subspecies may intergrade, especially at range boundaries;^[20] within the heart of their ranges, they look different.

• The male eastern painted turtle (C. p. picta) is 13–17 cm (5–6 in) long, while the female is 14–17 cm (6–7 in). The upper shell (carapace) is olive green to black and may posses a pale stripe down the middle and red marking on the margins. The scutes on the carapace have pale leading edges and occur in straight rows across the back, unlike all other North American turtles including the other three subspecies of Painted Turtle, which have alternating scutes.^[21] The bottom shell (plastron) is plain yellow or lightly spotted.^[22]

• The midland painted turtle (C. p. marginata) is 10–25 cm (4–10 in) long.^[23] Its top shell has darker coloration around the edges and less of a top stripe than the eastern painted turtle. Its bottom shell contains a dark area in the middle which varies in shade.^[6]

• The southern painted turtle (C. p. dorsalis), the smallest subspecies, is 10–14 cm (4–5.5 in).^[24] Its top stripe is a prominent red^[21] and its bottom shell is tan and spotless or nearly so.^[25]

• The western painted turtle (C. p. bellii), the largest subspecies, is up to 25 cm (10 in) long.^[26] Its top shell has a mesh pattern of light lines.^[5] The top stripe is missing or faint. Its bottom shell is covered in a dark coloration which spreads all the way to the edges (further than the midland).^[5]

Subspecies of the painted turtle

• 
  Eastern painted turtle
  C. p. picta
• 
  Midland painted turtle
  C. p. marginata
• 
  Southern painted turtle
  C. p. dorsalis
• 
  Western painted turtle
  C. p. bellii

Distribution

Current range

The painted turtle is the only North American turtle whose range stretches from the Atlantic to the Pacific. On the East Coast, it lives from Canadian Maratimes to Georgia. On the West Coast, it lives in British Columbia and Washington, with the range touching the Pacific near the US-Canadian border^[5] and offshore on southeast Vancouver Island.^{[27][nb 1]} The most northerly American turtle,^[27] its range includes most of southern Canada. To the south, its range reaches the US Gulf Coast in Lousiana. In the US Southwest and northern Mexico, there are only dispersed populations. It is not present at all in Florida.^[5]

• The eastern painted turtle ranges from southeastern Canada (Quebec, New Brunswick, and Nova Scotia, but not Prince Edward Island) to Georgia. The western extent of its range is approximately the Appalachians.

• The midland painted turtle ranges from southern Ontario and Quebec, through the eastern US Midwest states to Tennessee and Alabama. It also is found eastward through Pennsylvania, Virginia, West Virginia, North and South Carolina, Maryland, and into New England, where it may overlap the eastern painted turtle's range.^[11][25]

• The southern painted turtle ranges from southern Illinois and Missouri, roughly along the Mississipi River, to the south. Below Arkansas, it branches out to the west towards Texas and to the east, well into Alabama. In Louisiana, it reaches the Gulf of Mexico, but is not found on the rest of the Gulf Coast.^[25][28]

• The western painted turtle ranges from Ontario and British Columbia to the central and western United States. Its western boundary reaches the Pacific in the Seattle-Vancouver area. It is also found scattered throughout the southwestern United States and in the northern Mexico state of Chihuahua.^[5]

Habitat

To thrive, painted turtles need fresh waters with soft bottoms, basking sites, and aquatic vegetation. They finds their homes in shallow waters with slow moving currents such as creeks, marches, ponds, and the shores of lakes. Along the Atlantic, painted turtles have been seen in brackish waters.^[29] The four subspecies have evolved different preferences:

• The eastern painted turtle is more aquatic, only leaving the immediate vicinity of its water body when forced to migrate by drought.^[30]

• The midland and southern painted turtles seek especially quiet waters, usually shores and coves. They favor shallows that contain dense vegetation, and have an unusual toleration of pollution.^[24][31]

• The western painted turtle may live in streams and lakes, similar to the other painted turtles, but also inhabits pasture ponds and roadside pools. It can be found as high as 1,800 m (5,900 ft).^[26]

Population features

Within most of its range, the painted turtle is the most abundant turtle species. Population density ranges from 10–840 individuals per hectare (2.5 acres) of water surface. Warmth drives higher density both long-term (climate or lattitude) and short term (warm spells). Habitat desirability also influences density. Rivers and large lakes have lower densities because only the shore is desirable habitat; the central, deep waters skew the surface-based estimates. Also, lake and river turtles have to make longer linear trips to access equivalent amounts of foraging space.^[32]

Adults outnumber juveniles in most populations, but gauging the ratios is tricky because juveniles are harder to catch. With current sampling methods, estimates of age distribution vary widely.^[33] Annual mortality of painted turtles drops as they age. The probability of a painted turtle surviving from the egg to its first birthday is just 19%. For females, annual survival rate rises to 45% for juvenils and then to 95% for adults. Male survival rates are lower than females, creating an average male age lower than that of the female.^[34] Natural disasters can confound age distributions. For instance, a hurricane can destroy many nests in a region, resulting in less hatchlings the next year.^[34] Age distributions may also be skewed by migrations of adults.^[33]

Discovery of painted turtle fossils by age and location^{[35][nb 2]}

Age	Approximate years BP	Location(s) found (alphabetical)
Barstovian	16,300,000 to 13,600,000	Nebraska
Clarendonian	13,600,000 to 10,300,000	Kansas
Hemphillian	10,300,000 to 4,900,000	Nebraska
Blancan	4,750,000 to 1,808,000	Kansas, Nebraska, and Texas
Irvingtonian	1,800,000 to 300,000	Kansas, Maryland, Nebraska, and Oklahoma
Rancholabrean	300,000 to 11,000	Alabama, Georgia, Illinois, Indiana, Kansas, Maryland, Michigan, Mississippi, Nebraska, Nova Scotia, Oklahoma, South Carolina, and Virginia

Adult sex ratios of painted turtle populations average around 1:1, although with frequent departures from equality.^[36] Many populations are slightly male-heavy. However, a few populations are strongly female-imbalenced. One population in Ontario has a female to male ratio of 4:1.^[37] Hatchling sex ratio varies based on egg temperature. During the middle third of incubation, temperatures between 23 and 27 °C (73 and 81 °F) produce males, and anything above or below that, females.^[38] It does not appear that the female chooses nesting sites to influence sex of the hatchlings,^[17] and, within a population, nests will vary sufficiently to give male or female-heavy broods.^[33]

Fossils

The painted turtle is common in the fossil record. The oldest samples, found in Nebraska, date to about 15 million years ago. Fossils from 15 million to about 5 million years ago are restricted to the Nebraska-Kansas area, but more recent fossils are gradually more widely distributed. Fossils newer than 300,000 years old are present in most of the current range.^[35]

Behavior

Daily routine and basking

A cold-blooded reptile, the turtle regulates its temperature by changing its environment, notably basking. All ages of painted turtle bask for warmth, often alongside other species of turtle. Sometimes 50 or more individuals can be seen on one log at a time.^[39] Turtles bask on a variety of objects, often partially submerged logs, but have even been seen basking on top of common loons that were covering eggs.^[40]

To be active, the turtle maintains an internal body temperature between 17–23 °C (63–73 °F). When fighting infection, it will manipulate its temperature to be 4–5 °C (8–9 °F) higher than normal.^[39]

The turtle starts its day at sunrise, emerging from the water to bask for several hours. Warmed for activity, it returns to the water to forage.^[41] After becoming chilled, the turtle re-emerges for one to two more cycles of basking and feeding.^[42] At night, the turtle drops to the bottom of its water body, or perches on an underwater object, and sleeps.^[41]

Seasonal routine and hibernation

In the spring, when the water reaches 15 to 18 °C (59 to 64 °F), the turtle becomes active and feeds for the season. However, when the water temperature exceeds 30 °C (86 °F) the individuals will not forage. In fall, eating ceases at the same range it began in the spring.^[43]

In winter, the turtle hibernates. In the north, the inactive season may be as long as October to March, while the most southerly populations may not hibernate at all.^[30] During hibernation, the body temperature of the painted turtle averages 6 °C (43 °F).^[44] Periods of warm weather bring the turtle out of hibernation and, even in the north, individuals have been seen basking in February.^[45]

The painted turtle hibernates by burying itself, either on the bottom of a body of water, close to water in the shore-bank or the burrow of a muskrat, or fully offshore in woods or pastures. When hibernating underwater, the turtle prefers shallow depths, no more than 2 m (6 ft 7 in). Within the mud, it may dig down an additional meter.^[44]

Movement

Searching for water, food, or mates, the painted turtle travels up to several kilometers in a single trip.^[46] During summer, in response to heat and overgrowth of vegetation, the turtle may vacate shallow marshes for more permanent waters.^[46] These short overland migrations may involve hundreds of turtles at once.^[30] If heat and drought are prolonged, the turtle will bury itself, and, in extreme cases, die.^[47]

Foraging for food drives turtles to cross lakes or travel linearly down creeks. Daily crossings of large ponds have been observed.^[47] Capture, tag, and release studies show that sex drives turtle movement. Males travel the most, up to 26 km (16 mi) between captures; females the second most at up to 8 km (5 mi) between captures; and juveniles the least, less than 2 km (1.2 mi) between captures.^[46] Males move the most, and are most likely to move between wetlands, because they seek mates.^[47]

The painted turtle, through visual recognition, has homing capabilities.^[46] Many individuals are able to return to their collection point after being released somewhere else, a trip that may require them to traverse over land. One experiment was done in which 98 specimens were placed varying distances away from their home wetland. Of the original number, 41 returned. When living in a single, large body of water, the painted turtle can home from a maximum of 6 km (4 mi) away. Females may use homing to help locate a proper nesting sight.^[46]

Food chain

Diet

All subpecies of painted turtle eat plants and animals, either alive or dead, but with varying tendancies:^[43][48]

• The eastern painted turtle's diet is the least studied. It prefers to eat in the water, but has been observed eating on land. The fish it consumes is typically dead or injured.^[48]

• The midland painted turtle eats mostly aquatic insects and vascular and non-vascular plants.^[49]

• The southern painted turtle's diet changes with age. Adults of this subspecies obtain 88% of their food from plants, juveniles only 13% while the respective percentages of animal food are 10 and 85. This is perhaps due to the fact that the southern painted turtle naturally prefers animal material but, while young turtles are able to obtain it in sufficient quantities (by eating small larvae and such) the adults may not be able to, thus they seek out plant matter (the most abundant food in its habitat).^[50] The reversal of feeding habits due to age has also been observed in the false map turtle, which inhabits some of the same range. The most common plants eaten by adults are duckweed and algae. The most common prey are dragonfly larvae and crayfish.^[51]

• The western painted turtle's consumption of plants and animals changes seasonally. In early summer, 60% of its diet is insects. In late summer, 55% of its diet is plants.^[52] Also of note, white water-lily seeds are consumed by this turtle in high numbers. The hard-coated seeds remain viable as they pass through the turtle's digestive system, which suggests that the turtle is a significant seed disperser.^[52]

Foraging methods

Along the bottom of water bodies, the painted turtle hunts amidst vegetation. The turtle quickly juts its head in and out of aquatic plants to stir potential victims out into the open water, where they are pursued.^[43] Large prey is held in the mouth and torn up with the forefeet. The painted turtle also skims the surface of the water with its mouth open to catch fine particulate matter.^[43]

Predators

Painted turtles fall prey to many different animals throughout their lives.^[32] Eggs are eaten by garter snakes, crows, chipmunks, thirteen-lined ground and gray squirrels, skunks, woodchucks, raccoons, badgers, gray and red fox, and humans.^[32] Juveniles fall prey to water bugs, bass, catfish, bullfrogs, snapping turtles, three types of snakes (copperheads and racers and water snakes), herons, rice rats, muskrats, minks and raccoons. Adults are taken by alligators, osprey, red-shouldered hawks, bald eagles and, especially, raccoons.

Painted turtles defend themselves by kicking, scratching, biting, or urinating.^[32] Also, in contrast to land tortoises, painted turtles can turn themselves back over if they are flipped upside down.^[53]

Reproduction

Sex

The painted turtle mates in spring and fall in water of 10–28 °C (50–82 °F).^[29] Males start making sperm in March (earlier in southern populations) when they can bask to an internal temperature of 17 °C (63 °F).^[54][55] The female begins her ovarian cycle in mid-summer and ovulates the following spring.^[38]

Courtship begins when a male follows a female until he meets her face to face.^[19] He then strokes her face and neck with his front claws, a gesture which a receptive female returns. This process is repeated several times with the male retreating from and then returning to the female until she swims to the bottom, where they copulate.^[19][38] As the male is smaller than the female, he is not dominant.^[19] The female stores sperm, to be used for up to three clutches in a season, in her oviducts.^[56]

Nests

Nesting is done, by the female only, between late May and mid-July.^[38] The nests are dug in sandy soil and are vase-shaped and exposed to the south.^[57] Nests are often within 200 metres (660 ft) of water, but may be as far away as 600 metres (2,000 ft), with older females nesting further on land. The size of the nest varies depending on the geographic location and size of the female.^[57] Females may return to the same nesting site several years in a row, but when several females make their nests close together, the eggs become more vulnerable.^[57]

When preparing to dig a nest, the female sometimes presses her throat against the ground of potential sites, perhaps feeling for their moisture, warmth, texture, or smell, although the behavior is as yet unexplained. For the digging, she uses only her back legs. She may begin by excavating several false nests,^[57] a behavior also exhibited by wood turtles.^[58] The female accumulates so much sand and mud on her hind feet while digging that her mobility can be reduced, making her vulnerable to predators. The female's optimal body temperature during nest construction is 29 to 30 °C (84 to 86 °F).^[57] The process of digging and preparing the nest may take four hours to complete. Afterwards, there is a 75% chance she stays the first night.^[57]

To aid laying her eggs, the female moistens the area with bladder water.^[57] If it is too hot or dry, the female can delay her egg laying. The deposited eggs are elliptical, white, flexible and porous.^[59] In the wild, eggs incubate for 72–80 days before hatching:^[38] artificial conditions produce similar numbers.^[60]

The female can lay five clutches per year, but averages two. 30–50 percent of a population's females do not produce any clutches in a given mating season.^[57] Bigger females tend to lay bigger eggs and more eggs per clutch.^[61]

Clutch sizes of the subspecies vary, although the differences may reflect different environments, rather than different genetics. The two more northerly subpecies have more eggs per clutch, western (11.9) and midland (7.6), than the two more southerly subspecies, southern (4.2) and eastern (4.9).^{[nb 3]} Within subspecies, also, more northerly females lay larger clutches.^[57]

Young

In August and September, the young turtle hatches from its shell, using a projection of its jaw (the egg tooth) to break out.^[27] Not all offspring leave the nest, though. Hatchlings may overwinter in the nest to emerge the following spring.^[38] This is especially common in the north, where, even with shelter from the nest, freezing temperatures kill many hatchlings. While overwintering, the hatchlings arrange themselves symmetrically in the nest and remain responsive to touch.^[62]

Immediately after hatching, turtles are dependant on egg yolk material for sustenance.^[62] 7–10 days after emerging from the nest, hatchlings begin feeding to support growth. The young turtles grow rapidly, sometimes doubling in the first year, with the fastest rate when smallest. Likely owing to local habitat and diet, growth rates often differ from population to population in the same area. Among the subspecies, the western painted turtles are the fastest growers.^[63]

Overall, females grow faster than males, but must be larger to be sexually mature.^[64] In most populations, males reach sexual maturity at 2 to 4 years old, and females at 6 to 10.^[55]. At the northern edge of their range, males mature at 7 to 9 years of age and females at 11 to 16.^[19] Growth slows sharply once maturity is reached and may stop completely.^[64] Size and age at maturity increases with the latitude.^[65] In the wild, painted turtles aged 40 years have been found.^[43]

Conservation

Depopulation

The change in painted turtle populations is not a simple story of dramatic range reduction, like that of the American Bison. Instead the turtle remains numerous and occupies its original range—it is classified as of G5 (demonstrably widespread) in its Natural Heritage Global Rank—however, the settlement of North America has undoubtedly reduced its population density. Since at least 1952,^[50] scientists have noted human impact on the painted turtle. Ernst and Lovich, in their 2009 turtle almanac, acknowledge that estimates of species-specific population changes are lacking, but say that it is useful to discuss general factors affecting all turtles. However, these pressures are generally more pressing on turtles of the sea, estuary or land, or already rare turtles.^[66] The painted turtle's high reproduction rates and its ability to survive in habitats effected by humans, such as polluted wetlands and artificially made ponds, have allowed it to maintain its range.^[67]

Only at the extremeties of the Pacific Northwest is the turtle's actual range eroding. Even there, in Washington, the painted turtle is common: it is designated S5 (demonstrably widespread). However, further south in Oregon (the north third of the state is painted turtle range), the painted turtle is designated S2 (imperiled). There, federal, state and Portland city governments are working to better understand and arrest the decline of the painted turtle.^[40] North of Washington in British Columbia, the turtle is also in peril. Here coastal populations are designated endangered^[68] and interior populations are designated of special concern.^[69] The iconic painted turtle is popular in British Columbia and the province is further motivated to stop the loss of the painted turtle because it has already lost all populations of its other native turtle species, the western pond turtle. However, despite conservation efforts, only a few thousand turtles remain in the entire province.^[70][71][72]

Loss factors

Much has been written about the different factors that hurt the turtles. Essentially all factors are unquantified and at most only some inferences of which factors are more relatively severe are described.^[32][34][50]

Land development

An obvious threat to painted turtles comes from habitat loss by drying of wetlands. Even when water remains, the turtles may be impacted by the clearing of logs or rocks that provide basking sites. Also, clearing of shorelines vegetation may make allow more predator access,^[40] or increased human foot traffic,^[73][74] which make onshore sites untenable. Away from the water, urbanization or vegetation-planting, even for stream restoration, can remove the open sunny soils needed for nesting.^[40]

Roadkill

Another visible and probably numerically significant human impact is roadkill. Dead turtles are commonly seen on summer roads: in 1974, Ernst measured 14 deaths in a single day on one short stretch of Pennsylvania road.^[40] Increased traffic as well as increased road penetration of habitat worsens the problem over the years. Turtle surveys near busy roads showed that males strongly outnumbered females. This suggests most road casualties were nesting females. Males roaming for mates or changing waters from drought could usually find water routes to move along, but the females had to come on land to lay eggs.^[40] In addition to direct killing, roads impact the painted turtles indirectly by isolating some populations genetically.^[40]

Various roadkill reduction efforts are being tried. Portland, Oregon built an undercrossing, for $160,000, which the turtles have learned to use.^[40] In 2012, Montana will build highway barriers on U.S. Route 93 near Ninepipe National Wildlife Refuge.^[53] Less dramatic interventions have included road signage "turtle crossing" as well as public education. States counsel drivers to (safely) avoid turtles by swerving or to assist turtles in crossing. Oregon's Regional Conservation Biologist, Susan Barnes, writes, "Stopping to help a turtle cross a road is always a question of human safety. If you can safely get off the road and carry the turtle to the side of the road in the direction it is headed, it’s O.K."^[75]

Introduced species

Red-eared slider are the major pets and are native to the U.S. Southeast only. They have been widely released (or escaped) and have established breeding populations in many parts of the painted turtle range, including Canada. They are a similar species in size and habits to the painted turtle, so they may be added competition, but the impact is uncertain. In the U.S. Northeast, the painted turtle already shares territory with yellow-eared sliders (which mix readily with red-eared sliders), so the pet-released invasions are less likely to be a significant new threat.

In the West, several predators of youngling painted turtles have been introduced into waters where they never roamed before: bass, snapping turtles, and bullfrogs. Examination of bullfrogs and bass in Montana shows they are consuming few painted turtles.^[53] Snapping turtles may have more impact and in Oregon, aggressive trapping has been done to remove them.^[40]

In urban areas, increased egg-eating raccoons, foxes, and coyotes, as well as feral dogs or cats, may impact painted turtles. Some cities have experimented with nest enclosures to screen out predators. ^[40]

Other concerns

Taking painted turtles from and releasing them into wetlands can both be harmful. Initially, local populations may be decimated by over-collection as most adults for sale are from the wild. Ernst recounts an example of a pet collector in Pennsylvania removing an entire water body's turtles. Later, pet releases may introduce salmonella or poor genes to wild populations.^[40]

Pollution may be a danger in a few different ways: pesticides for misquitos killing off aquatic prey in turtle ponds, herbicides hurting aquatic vegetation, or just generalized water pollution impacting turtles. However, no definite impacts have been quantified.^[40]

Outdoor recreation also affects turtles. Boating traffic near basking sites can disturb painted turtles. Some turtles die indadvertantly on fisherman's hooks—the turtles are noteworthy for stealing bait. Oregon is considering stream access modifications to reduce wanton shooting.^[40]

Gervais notes that turtle research itself impacts the populations. Many turtle surveys have been done, which did not result in publication. She advocates developing computer-based population models instead, to better understand evolution of painted turtle numbers, and reserving catch and release studies to test specific hypotheses.^[40]

Similar to road deaths, agricultural machinery kill females and destroy nests. Some states describe death from lawnmowers (particularly on golf courses).^[40][76] Others warn against indiscrimante all terrain vehicle riding affecting the turtles.^[40][77] Global warming represents an uncharacterized future threat.^[40][66]

Gain factors

In California, some painted turtle populations probably resulted from pet releases. There, they are an invasive species that endangers the local western pond turtle, although competition from similarly-released red-eared sliders is the higher threat. ^[78] In New England, the Turtle Conservation Project notes: "Ironically, prime habitat has been created by fertilizer runoff, creating vegetation-clogged lakes; just what Painted Turtles like."^[79]

Uses

Pets

In the early 1990s, U.S. export data showed that painted turtles were the second most popular pet species, after red-eared sliders.^[59] During the 1990s, more than 300,000 painted turtles were collected for the pet trade in the state of Minnesota alone.^[40]

Most U.S. states allow, but discourage painted turtle pets. Oregon forbids keeping them as pets^[81] while Indiana prohibits their sale.^[82] U.S. federal law prohibits sale or transport of any turtle less than 4 inches in order to limit human contact to salmonella.^[83] However, a loophole for scientific samples allows some small turtles to be sold and illegal trafficking also occurs.^[40][84]

Painted turtle pet-keeping requirements are similar to those of the red-eared slider. Keepers are urged to ensure the animals have adequate space, both water and a basking site, some method of water filtration, and frequent water changes. The animals are described as being somewhat unsuitable for children as they do not enjoy being held. Hobbyists have kept turtles alive for decades.^[85]

Other uses

The painted turtle is sometimes eaten but is not highly regarded as food^[50][86][87] as even the largest subspecies, the western painted turtle, is too small for convenience and other, larger, turtles are available.^[88] Pennsylvania says that wild-caught meat is safe to eat, but advises cutting away fat and internal organs which may concentrate PCBs.^[89] Schools frequently dissect painted turtles; specimens often come from the wild, but may be captive-bred.^[90]

Capture

In the U.S., the painted turtle is not federally protected. Many states allow open-season taking of painted turtles with a fishing license, but some do protect their turtles. Alabama allows taking, with a creel limit of ten, of all three subspecies (southern, midland, and eastern) found there, for personal use,^[28] but also has a special license for commercial turtle catchers, dealers and farmers.^[91] Virginia allows taking with a fishing license with a creel limit of five.^[76] Michigan allows open-season taking of one per day, for non-commercial use.^[92] Pennsylvania allows one capture per day, from water, with a fishing license.^[93] New Hampshire confines taking to the summer.^[94] Arizona allows taking four per year with a hunting license.^[77] Oregon, where its western painted turtle populations are under pressure, forbids taking of any kind.^[95] Missouri forbids the taking of either subspecies (western or southern) present there.^[96]

Capturing methods are also regulated by locality. Traps are most common although set lines are also used, as are nets and hand capture. Traps must generally be floating or partially submerged so captured turtles can breathe; trap size, number, construction, and labeling may also be regulated. Several states describe a practice of wanton shooting of turtles "for fun" (two studies of this have been done)^[40] and prohibit it, or prohibit even deliberate taking with firearms. Use of chemicals or explosives is also generally disallowed. Because other, less numerous, turtle species may be more heavily protected, methods of collection are restricted to allow the release of protected species.^{[28][76][77][92][93][94]}

Culture

Native American tribes noticed the painted turtle—young braves were trained to recognize its splashing into water as an alarm—^[97]and incorporated it in folklore. A Potawatomi myth describes how the talking turtles, "Painted Turtle" along with allies "Snapping Turtle" and "Box Turtle", outwit the village squaws. Painted Turtle is the star of the conflict and uses his distinctive markings to trick a woman into holding him so he can bite her.^[98] An Illini myth recounts how Painted Turtle put his paint on to seduce a chief's daughter into the water.^[99]

In addition to the California camp for ill children founded by Paul Newman, some other business names are inspired by admiration of the species. Wayne State University Press operates an imprint "named after the Michigan state reptile" that "publishes books on regional topics of cultural and historical interest".^[100] Painted Turtle Winery of British Columbia trades on the "laid back and casual lifestyle" of the turtle with a "job description to bask in the sun".^[101] Also, there is a guesthouse in British Columbia^[102] and a cafe in Maine.^[103]

The painted turtle is the official reptile of four U.S. states:^{[nb 4]} Colorado (western subspecies),^[104] Illinois,^[105] Michigan,^[106] and Vermont.^[107]

References

Notes

Footnotes

Bibliography