Kinosternon flavescens
yellow mud turtle

Yellow mud turtles range throughout the midwest United States, from the northern parts of Mexico to as far north as Nebraska. Yellow mud turtles are also found in eastern New Mexico, Oklahoma, southeast Arizona and western Kansas. There are disjunct populations in northeast Missouri and central Illinois. (Bartlett, 2006; Carr, 1952; Conant, Collins, and Conant, 1998)

Yellow mud turtles are found in freshwater habitats. They are found in small permanent and temporary ponds. Yellow mud turtles are found mainly in smaller ponds with muddy bottoms with little or no vegetation. In arid regions yellow mud turtles can be found in cattle tanks, ditches, and sewer drains. When their small pools and ditches start drying up, yellow mud turtles can be found buried beneath the mud. (Bartlett, 2006; Carr, 1952; Conant, Collins, and Conant, 1998; Pope, 1946; Webster, 1986)

Yellow mud turtles have high-domed carapaces. The scutes are rounded and smooth, but the ninth and tenth scutes are larger than the others. The carapace can be olive green, brown, or tan with the borders of each scute bordered in black. Males are slightly larger than females. Males have larger heads than females, but they are more flattened on top. The head, neck, and limbs are the same color as the shell, but the chin and cheeks are yellowish. Yellow mud turtles range from 10.2 to 15.2 cm in body length. Female yellow mud turtles have an average size of 11.4 cm, males are slightly larger with an average size of 14 cm. Average mass is 391 g. (Bartlett, 2006; Carr, 1952; Conant, Collins, and Conant, 1998; Iverson, 1991; Pope, 1946; Webster, 1986)

As soon as yellow mud turtles have hatched the new young are nearly independent. Some female turtles stay with the young for a few days, but others abandon the eggs. Once hatched, these turtles begin looking for food. (Bartlett, 2006; Carr, 1952; Ernst and Barbour, 1972)

Yellow mud turtles have a lifespan of about fifteen years in the wild. Turtles in captivity have a lifespan of roughly ten years. (Ernst and Barbour, 1972; Iverson, 1991)

Yellow mud turtles are seasonally diurnal. During the winter months they bury themselves underground and hibernate. They use their stout legs and claws to swim and to bury themselves in mud. When encountering other yellow mud turtles, male makes contact to determine the sex of the other turtle. (Ernst and Barbour, 1972; Tuma, 2006)

Home Range

Yellow mud turtle home ranges are limited by pond size. Yellow mud turtles co-occur in ponds and are not aggressive among themselves. Yellow mud turtles wander from ponds in search of mates or in search of other water sources if food is scarce. On average, adult turtles will wander from 190 m to 220 m. Juveniles venture only about 180 m from the water. (Bartlett, 2006; Harless and Morlock, 1979; Pope, 1946; Tuma, 2006)

Yellow mud turtles use touch to communicate with other yellow mud turtles. They use scent for social communication and to detect prey. Yellow mud turtles emit a strong musky odor when threatened by a predator. (Christiansen and Dunham, 1972; Schmidt and Inger, 1982)

Yellow mud turtles are omnivores with a broad diet. Animals consumed range from small insects to amphibians and reptiles, as long as they are smaller than the turtle. Yellow mud turtles generally forage in the water, but sometimes find food on the surface of the water or on land. Their sense of smell and taste enable these turtles to locate food easily under water. Yellow mud turtles eat vegetation, carrion, fish, shrimp, crayfish, snails, and small clams. Yellow mud turtles also prey on the eggs of other turtles and fish. During dry seasons, yellow mud turtles bury themselves in mud or dirt and prey on earthworms, insects, spiders, and ticks. (Carr, 1952; Ernst and Barbour, 1972; Pope, 1946; Webster, 1986)

Yellow mud turtles have few natural predators as adults. As eggs and young they are preyed on by skunks, raccoons, other turtles, water snakes, and large predatory fish. When yellow mud turtles are threatened they release a potent smell from their bodies which may repel predators. (Ernst and Barbour, 1972; Iverson, 1991)

Feces from Kinosternon flavescens helps with soil fertilization. Yellow mud turtles help regulate population size of small fishes and amphibians by feeding on the eggs of many species. Yellow mud turtles are parasitized by leeches, Macrobdella decora, which attach themselves to the skin of their legs and tails. Algae are also found on the shells of yellow mud turtles, including Basicladia chelonum and Basicladia crassa. Algae typically had no harmful effect on the turtle but, in rare cases the algae harmed the strength of the shell. (Ernst and Barbour, 1972; Kofron and Schreiber, 1985)

Kinosternon flavescens flavescens was introduced to portions of Arizona and may have become an aquatic nuisance species there. (Fitzsimmons, 2001)

Yellow mud turtles are important predators of fishes, snakes, and other turtles in their native ecosystems. (Ernst and Barbour, 1972; Pope, 1946)

Yellow mud turtle populations are stable throughout most of their range. Yellow mud turtles are not endangered or threatened in northern Nebraska through Texas and into Mexico. In Missouri K. f. flavescens is listed as state endangered. Kinosternon flavescens spooneri is on the state-endangered list in Illinois. (Bickham, Springer, and Gallaway, 1984; Kofron and Schreiber, 1985)