Harmless · Native to the United States

Western rat snake

Pantherophis obsoletus (Say, 1823)

Also called black rat snake; Texas rat snake (southern form)
Data updated October 2026

Glossy black western rat snake coiled on pine needles, with a pale chin
Fig. 1 — Many adults are glossy black, with a white chin and lips.
Western rat snake climbing straight up the trunk of a large tree
Fig. 2 — An expert climber that often hunts and basks in trees.

At a glance

One of the largest snakes in the central United States, usually glossy black with a white chin. It climbs well, eats rodents, birds and eggs, and is harmless to people.

01

Identification

Adults are usually glossy black or very dark brown, sometimes with faint darker blotches. The upper lip, chin and throat are white, and the belly is white. The scales are keeled and the anal plate is divided. Young snakes look very different: gray or tan with bold dark blotches and a black band through the eye. They darken during their third year. In Texas and Louisiana, many adults keep a blotched pattern with reddish edging between the blotches.

  1. 01Dark, glossy body. Black or dark brown in most adults, often with a faint pattern in good light.
  2. 02White chin and lips. A clean white throat that contrasts with the dark head.
  3. 03Blotched young. Gray or tan young with dark saddles that are longer than wide.

Commonly confused with

Young western rat snakes are easily confused with Great Plains rat snakes. Large dark adults near water are sometimes mistaken for cottonmouths, which are much stouter and have a broad, flat head.

02

Size

01 ft2 ft3 ft4 ft5 ft6 ft7 ft8 ft Typical adult · about 5 ft (152 cm)

Most adults measure 42 to 72 inches (107–183 cm). The largest on record reached about 86 inches (218 cm). The Kansas record is just over 75 inches.

03

Range & habitat

Western rat snake stretched along a thin branch among green leaves
Fig. 3 — Rat snakes travel through shrubs and tree branches as easily as on the ground.

Western rat snakes live in the central United States west of the Mississippi River. They occur across Missouri, the forested eastern half of Kansas and along wooded rivers farther west, and south through Oklahoma into Texas and Louisiana.

They are mainly woodland snakes, favoring rocky, wooded hillsides and woods along streams and rivers. They are also common around barns, old houses, brush piles and suburban yards. Winter is spent in mammal burrows, rock outcrops, caves or hollow trees.

State guides: Texas · Oklahoma

04

Diet & predators

Western rat snakes kill prey by constriction or swallow it whole. Adults eat rodents, small rabbits, bats, birds and bird eggs, and sometimes lizards. Young snakes take frogs, lizards, insects and small rodents.

Feeds on

  • Rats and mice
  • Birds and their eggs
  • Bats and small rabbits
  • Frogs and lizards (young snakes)

Preyed on by

  • Hawks, the main predator
  • Raccoons and skunks (eggs and young)
  • Other mammals and snakes

05

Behavior & seasons

Western rat snakes are active from early April through October. They hunt by day in spring, early summer and fall, and turn nocturnal in hot weather. When alarmed they may vibrate the tail, strike, and release a musky odor.

They are excellent climbers and often bask in trees. When are snakes active in Texas?

06

Reproduction

Mating takes place mostly in spring, but also in summer and fall. Females lay their eggs in June or early July in rotten logs, tree holes or mulch piles. Clutches range from 4 to 40 eggs in Missouri and 6 to 44 in Kansas. The eggs hatch after 42 to 84 days. Young mature in three to four years.

07

Conservation

The western rat snake is common and often seen around homes and farm buildings. It has no special conservation status and is widely valued for eating rodent pests.

Keep reading

Sources

Data updated October 2026 · How we build these pages