Photo courtesy of Sabine River Authority
Alligator Snapping Turtle (Macrochelys temminckii)
The Alligator Snapping Turtle, scientifically known as Macrochelys temminckii, is found exclusively
in the United States. This turtle’s population is in jeopardy partially due to commercial overharvesting for their
meat and recreational bycatch from trotlines and other unattended harvest methods.
Nest predation of turtle eggs by predators is a major source of mortality in many turtle populations. A fully
grown alligator snapping turtle’s only main predator is people.
The Texas Parks and Wildlife Department (TPWD) considers the alligator snapping turtle a threatened species, and it is protected
in the state of Texas. Meanwhile, the U.S. Fish and Wildlife Service has published a proposed Endangered Species Act Threatened
status with a 4(d) rule to afford further protections.
Alligator snapping turtles are provided some protection by the Convention on International Trade in Endangered Species of Wild
Fauna and Flora, limiting commercial export and trade of the species.
If an alligator snapping turtle is caught, it should be returned to its habitat, as close as possible to the spot where it was caught.
Current Range Map
While not currently documented in the Brazos River basin, the alligator snapping turtle’s range is immediately adjacent to the
east of the basin. Therefore, it’s likely there are some of these animals in the Brazos basin.
If you see an alligator snapping turtle in the Brazos basin, the Texas Parks and Wildlife Department would like to know. Report
the sighting by texting a photo and the location to 281-302-8033. Don’t get too close, though. These animals are large and
powerful and can be aggressive.
Alligator snapping turtles live in rivers, lakes, and wetland habitats. These predominately aquatic species primarily spend their
time submerged, needing to come to the surface for air about every hour. Males don’t leave the water, while egg-laying females
only come on land to nest and lay eggs.
Males alligator snapping turtles are somewhat larger than females, and they also have a longer tail base (anterior to vent).
The gender of the turtles depends on the average temperature of the eggs during incubation. Low and high temperatures
will produce female offspring, while intermediate temperatures will produce male offspring. It takes 11 to 13 years for one
to reach maturity. In the wild, they can live up to 45 years. In captivity, they have lived 70 years.
Adults mate in the spring and eggs are laid two months later. Nesting season is May to July, and each nest can have
nine to 44 eggs. They hatch in roughly 70 to 105 days.
Growth is rapid until maturity (11-21 years of age), slowing after 15 years of age.
The Texas Comptroller’s office is sponsoring a Baseline Study of Alligator Snapping Turtle Population Viability in
Texas Watersheds through 2023. TPWD Urban Wildlife Biologists are performing extensive surveying in Harris County.
For more information, go to: