Garter Snake

Giant Garter Snake

Facts, Identification & Control

Latin Name

Thanophis gigas

Morphology

The giant garter snake is among the largest snakes in North America. The scaly skin color can be brown, black or olive with checkered pattern or yellowish stripes. The neck is narrower than the head. Distinct stripes can be seen on snakes at the northern end. The color of giant garter snakes in San Joaquin Valley is usually light gray or light brown with indistinct or even no stripes. They are the largest among the garter snake species. They are usually 36 – 48 inches but some can reach a length 65 inches.

Diet, Behavior & Habits

From Kern County north, to butte County to southern part of Francisco nay delta, to Merced County and Northern Fresno, giant garter snake can be found all over California. It inhabits sloughs, marshes, irrigation ditches, drainage canals and rice fields. It also live in wetlands created by human activity. It is very agile during hot night and most active during the day. It is very fast in getting away from predators and it will move swiftly to the bottom of the river before an approaching person could make any move. This is due to the many airborne predators like hawks, egrets, herons etc. that it shares it habitat with. The snakes come out of hibernation in March and stay on any vegetation beside water to keep warm during spring. They remain agile till fall and go into hibernation in abandoned animal holes. Rodents, frogs, ants, earthworms, leeches, tadpoles, fish and other animals it can easily overpower are its prey.

They mate after emerging from overwintering sites during spring. Their breeding period is between July and September. It produces foul-smelling musk when it is picked up or threatened.

More details

Due to the destructive human activity on wetland habitat, the state of California and U.S. fish and wildlife service has classified giant garter snake has “threatened”. The population of the giant garter snake in San Joaquin Valley is very small compared to what it used to be. Due to cultivation of rice in Sacramento valley, the population of giant garter snake is considerably high here. American bullfrog and other introduced predators are also part of the causes of the reduction in their population. The population of giant garter snake is likely to increase and it has been labelled as “high recovery potential” because of the improvement in the maintenance of federal and state wetlands.

Contact pest management professional (PMP) if you are experiencing any problem with the snake to help you control it. The snake move into human habitat while searching for shelter and food. You should ensure that you terminate all food sources for the snake and also ensure that you destroy any thing that can serve as shelter for them.