Macrochelys temminckii

Mostly sedentary, these turtles spend much of their time resting on the bottom of rivers, lakes, and swamps. They employ an ambush strategy—remaining motionless with jaws open and wriggling their fleshy tongue to mimic prey—snapping shut in milliseconds when fish or amphibians approach.

Breeding occurs in spring and early summer when females leave the water to nest on sandy or gravelly banks. After laying a clutch of 20–50 eggs, the mother covers them with soil; hatchlings emerge in late summer or early fall and are entirely independent from birth.

Adults can weigh over 100 kg (220 lb) and measure up to 80 cm (32 in) in shell length, making them the heaviest freshwater turtles. Their rough, knobby carapace provides camouflage among logs and submerged debris, while muscular jaws crush prey, including fish, mollusks, and even small mammals.

First described by Dutch zoologist Temminck in 1815, this species’ lineage dates back over 14 million years. Native to river systems of the southeastern United States, it once ranged broadly but has become less common in many parts of its historical habitat.

The Alligator Snapping Turtle is classified as Vulnerable due to overharvesting for food, habitat degradation, and bycatch in fishing gear. Conservation measures include regulated harvest, habitat protection, and head-start programs that rear hatchlings in captivity before release to bolster wild populations.