Creature Feature

Getting to Know Garter Snakes

By Wayne Bierbaum 

I rarely see a snake in my yard. I have well-groomed yards all around and no wild area within a half a mile. Over the 20-plus years I have lived in the house, two black racers (one juvenile and one adult), one juvenile black rat snake, one DeKay’s brown snake, one ribbon snake and one common garter snake (gravid) have been found in my yard.  

Today, I had a visit from another garter snake. I was walking through the grass and almost stepped on the 15-inch reptile. Because the area where I live would be a high danger risk for the snake, I gently picked it up, put it into a large bucket and released it into a marsh.  

Garter snakes are the most common snakes in North America. They range from Costa Rica to Alaska, where it is the only type of snake around. They are found in jungles, deserts and even near the Arctic Circle. There are some 35 species or subspecies that can be a dull brown to the vivid red of the California red-sided garter snake.  

All have stripes down their sides and usually a third stripe down the middle of the back. Maryland has two species, the ribbon snake and the Eastern garter snake and here they are all fairly small, usually less than 24 inches long. The largest variety in the U.S. has been recorded at a little more than 4 feet long. 

They are a keeled scaled snake; their skin is not shiny like a smooth-scaled snake. Each scale has a longitudinal ridge down the middle. Keeled scales may help them move easier especially through water. They are good swimmers and will take to the water to escape.   

Garter snakes are active during the day and feed on insects, fish, amphibians, reptiles and occasionally small birds and mammals. They are said to possess a mildly poisonous saliva that stuns its prey. The poison is also mildly irritating to humans. Luckily, the snakes are not aggressive and bite only when roughly handled. They usually choose to hiss and look menacing. When handled they frequently exude and smear a smelly musk that comes from glands at the base of their tail. 

Like all reptiles, they are “cold-blooded” which means their body temperature stays close to that of their surroundings. On a cool morning, they will bask in the sun to increase their metabolic rate. They are slow and sluggish in the cold. When winter comes, they will find a spot, usually underground, and go into an almost inactive state called brumation. In the northern part of the range, such as in Canada, there are frequently snake dens where sometimes hundreds of the reptiles spend the winter together. Some snakes come from long distances to the den.  

The advantage of these large dens is that as they emerge in the spring, they can mate immediately without traveling long distances. The females, like many turtles I have studied, store the sperm until the conditions are right for her to fertilize her eggs. They are ovoviviparous, meaning the fertilized eggs mature and hatch inside of the female and then emerge as live young. The six or so offspring immediately fend for themselves.  

Each individual animal has its own temperament and that changes with the situation it finds itself in. The garter snake I caught and relocated was calm and did not try to bite. I did not grab it behind its head, as that usually causes them to start making musk. I held its tail and then slowly lifted it but supporting its midsection. At a marshy area, I let it go on a low tree branch so I could take a photo.  

Garter snakes are generally too active and nervous to make good pets. Even so, some of the more colorful types are becoming rare because of over collecting for the pet trade. Since they do eat insects, they are somewhat beneficial. They certainly are not dangerous and should be allowed to coexist with us.