Snakes in South Dakota: Identification Guide and Best Places to Start

Snakes in South Dakota are most often seen in the western part of the state, especially in Badlands National Park and the surrounding shortgrass prairies. Look along rocky slopes, prairie dog towns, and near water sources like the Cheyenne River. In the east, garter snakes and bullsnakes turn up in gardens and along wooded edges.

See our state wildlife page for the next step.

Snakes are most active from late April through September. The best time to spot them is on warm mornings (70–85°F) when they bask on rocks or trails. After a rain, snakes often move across roads or trails. Early spring and fall offer lower vegetation, making them easier to see.

See our Snakes guide for the next step.

The prairie rattlesnake has a thick body, a triangular head, and a rattle on the tail. Its patterns are diamond-shaped blotches. The bullsnake is longer and thinner, with a pointed head, no rattle, and a blotched pattern that looks similar but has a dark line from the eye to the jaw. Bullsnakes often hiss and flatten their heads when threatened.

See our state animal guide for the next step.

Besides the prairie rattlesnake, common species include the plains garter snake, red-sided garter snake, bullsnake, eastern yellow-bellied racer, and the smooth green snake. The northern water snake is found in the eastern rivers. Most are harmless and help control rodents.

Stop and give it space. Most snakes will move away if you stay still. If it's a rattlesnake, step back slowly. Do not try to handle or prod it. Keep dogs on a leash in snake country. Learn to identify the venomous species before heading out.