Rat Snake

Elaphe obsoleta

Rat Snake

RASN

Status

The Rat Snake is common throughout its range.

Description

The Rat Snake is one of the largest (42–256 cm) and most variable species in the United States. The Black Rat Snake, E. o. obsoleta, has a black or dark brown dorsum, often with a faint white pattern. Its venter is mottled gray and white. The Yellow Rat Snake, E. o. quadrivittata, is greenish or yellowish with four prominent, dark brown longitudinal stripes. Some adults have a faint saddled pattern. The venter is white or pale yellowish-brown. The Gray Rat Snake (Elaphe o. spiloides) retains the strongly blotched juvenile pattern throughout life. It is gray to pale brown with brown to gray blotches. The Texas Rat Snake (Elaphe o. lindheimerii) is also a blotched Rat Snake but often with less contrast than the Gray Rat Snake. Blotches are usually brown to black and there is often red on the skin between the scales and even on the scale edges. Juveniles of all subspecies have conspicuous gray or brown blotches or saddles on a light gray or yellow brown background. Five subspecies have been described: lindheimerii, obsoleta, quadrivittata, rossalleni, and spiloides (Mount 1975).

Distribution

Rat Snakes range from New England to Florida, and westward to Nebraska and western Texas.

Habitat

Rat Snakes are common in a variety of habitats. They are excellent climbers and are frequently found in snags, hollow trees, rural buildings, and vine tangles. Habitats include upland hardwoods, pocosins, river swamps, bottomland hardwoods, fields, mixed pine habitats, white pine-hemlock, rocky pine hillsides, and live oak habitats. They attain the greatest densities in areas where forests and farmland are generally intermixed and small mammals are abundant (Mount 1975).

Special Requirements

Elaphe obsoleta requires shelter in the form of old buildings, snags, hollow trees, logs, and surface debris, as well as a supply of rodents for food.

Breeding Habits

Mating occurs during spring, and eggs (clutch size 5–25 eggs) are deposited during late spring or summer. Nest sites include logs, stumps, sawdust piles, hollow trees, and snags.

Food Habits

Small Rat Snakes eat lizards, small amphibians and young mice. Adults prey on rodents, birds, and bird eggs.

Management Suggestions

Snags, fallen trees, and similar structures should be retained in primary habitats. Additional practices are not considered necessary at this time.

Additional References

Fitch 1963b; Jackson, 1976; Saxton and Hunt 1980; Stickel and others 1980.