Snake, Grey Rat

Elaphe obsoleta spiloides   

This large, often beautiful snake reaches a length of 84 inches. It varies in color. Some populations are a smoky white gray with gray
blotches surrounded by thin black lines. Others may be dark gray with brownish gray blotches. The head is uniformly gray to brownish. The scales are weakly keeled. The belly is gray with faint blotching. Some adults are striped.








Southern Georgia and northern Florida west through Mississippi and north to southern Kentucky


Wooded areas around swamps, other wetlands or open grasslands and often found in old buildings and barns, even in suburbs and towns

Life Expectancy

Up to 19 years

Sexual Maturity

Approximately 18 months


In the wild, rat snakes eat mice, rats, other small rodents, bird eggs, and baby birds. In the Zoo, they are fed mice and rats.


Not listed


When alarmed, the gray rat snake will coil and strike repeatedly. Like most snakes, rat snakes are egg layers. Between March and May, snakes will begin to emerge from winter’s hibernation. After a few weeks, rat snakes begin to seek out a mate, typically in late April, May, and early June. Males tend to wait for the females to pass through their territory, and by using pheromones, will communicate and initiate the mating process with the female. A male will approach a female, line up with her and attempt to wrap his tail around her tail with their vents nearly touching. Some males will grasp females with their mouths to hold them in place and prevent their escape. The male will then erect his hemipene and insert it into the female’s cloaca while several small spines anchor the hemipene firmly. Mating can last only a few minutes or it can span the time of a few hours. Five weeks later, the female will lay around 12 to 20 eggs. The female will lay her eggs in a hidden area, under hollow logs or leaves, or in abandoned burrows. The eggs will hatch 65 to 70 days later. The hatchlings of common rat snakes are vigorous eaters and will double their size rather quickly. If conditions are good, females will sometimes produce two clutches of eggs a year. Rat snakes are primarily known as rodent eaters, however, other food preferences do exist. As juveniles, rat snakes will eat small lizards, baby mice, and an occasional small frog. Adult rat snakes have a diet mainly consisting of mice and rats, but will also include chipmunks, moles, and other small rodents. Adults will also eat bird eggs and young birds that do not put up a strong fight. Rat snakes kill their prey by constriction.


The gray rat snake is an excellent climber. It is one of the constrictors. It uses its body to squeeze its prey until it is dead and then will swallow it whole.

Special Interests

The genus name Elaphe is derived from the Latin word elaps (a kind of snake). The species name obsoleta is from the Latin obsoletus (worn out), a reference to the loss of the juvenile pattern in adults. The gray rat snake keeps the blotched juvenile pattern its entire life. The blotches will vary between dark gray and brown. Juvenile black and yellow rat snakes are often mistaken as juvenile gray rat snakes. Large adults have few predators other than humans. Carnivorous mammals and raptors are the main predators of juveniles. The gray rat snake is also called the oak snake, a reference to its pattern that resembles oak bark.


Melampus was kind to animals, and after he raised a nest of orphaned snakes, they licked his ears clean as gratitude, and from then on he could understand the language of animals.


The rat snake’s habitat is slowly being reduced due to land development and the clearing of trees. Despite these challenges, the population remains healthy. Due to people’s lack of knowledge and fear of snakes, rat snakes continue to be the victim of human persecution.

Jacksonville Zoo History

This species first appears in the Zoo’s animal collection sometime prior to February 5, 1966. It has bred here, however, all the offspring were of different subspecies crosses.


Wild Florida