Alligator Snapping Turtles

Action Update from the May 2009 WildSide

alligator snapping turtle
Commonly confused with the common snapping turtle, Chelydra serpentina ,which is found throughout Oklahoma, the alligator snapping turtle, Macrochelys temminckii, is restricted to portions of the Arkansas River and Red River watersheds in the eastern quarter of the state. Unlike the common snapping turtle, the alligator snapping turtle spends its whole life in a small area with females only leaving the water to lay eggs which minimizes its dispersal capability.

Due to several man-made causes such as commercial harvest for their meat and destruction of habitat, the populations of alligator snapping turtles have steadily declined over the past century. An effort to develop a program to restock populations in watersheds is currently being considered. Two captive populations of turtles exist in Oklahoma that could be used as brood stock for this type of project. A private breeder in Perry has a stock of alligator snappers from Missouri. Additionally, the Tishomingo National Fish Hatchery houses captive-bred Oklahoma turtles.

Oklahoma State University conducted a study to test if potential negative impacts exist in restocking this species if genetic differences exist between river drainages. Alligator snapping turtles were captured from tributaries occurring in Sequoyah National Wildlife Refuge, Little River NWR, the Kiamichi River, and the area around Lake Eufaula. Captured individuals were marked and a sample of blood samples was collected from which DNA was extracted. Additionally, DNA was extracted from blood samples collected from individuals in the populations at the Tishomingo National Fish Hatchery and the captive populations in Perry.

Results showed there was a lack of genetic variation among native turtles and captive alligator snapping turtles. Therefore, with a proper management and restocking plan, the two captive populations would make good sources for reintroduction throughout Oklahoma which could help ensure this unique turtle’s survival.

Written by Buck Ray. Buck is the environmental biologist with the Oklahoma Department of Wildlife Conservation.

This project is funded by the State Wildlife Grant Program. The State Wildlife Grant Program provides federal money to every state and territory for cost-effective conservation aimed at preventing wildlife from becoming endangered. This program is administered by the Oklahoma Department of Wildlife Conservation and continues the long history of cooperation between the federal government and the states for managing and conserving wildlife species.