Please see Part I of this article for background information on these snake-keepers’ favorites. Garter Snakes and the closely related ribbon and water snakes usually make hardy captives, yet there are very few records of individuals surviving over 10 years. I believe this may have to do with some of their unique environmental and dietary needs (I’ll cover temperature, light and diet in Part III of this article).
Natural vs. Captive Habitats
Nearly all garter and ribbon snakes favor swamps, wet meadows, pond edges and other moist habitats. Oddly, however, they are very susceptible to skin infections (“blister disease”) when kept on damp substrates – even more so than snakes native to dry environments. This holds true even for those that spend a great deal of time in the water, such as the Aquatic Garter Snake (Thamnophis couchi), the Ribbon Snake (T. sauritus) and the True Water Snakes (Nerodia sp.).
While all should be given water in which to soak, the substrate must remain dry. The aforementioned species may be kept in semi-aquatic terrariums that allow for swimming, but they must have access to warm, dry basking sites (branches over water work well). Shy specimens that will not bask should be moved into terrestrial situations with just a bowl of water available.
Curing Blister Disease
A Northern Water Snake (Nerodia sipedon) that I kept decades ago developed skin blisters after only 2 weeks of a largely aquatic existence. I wrote to famed reptile man Wayne King, then curator of reptiles at the Bronx Zoo. His advice to move the animal to a dry terrarium and provide a warm but sheltered basking site worked like a charm, and the snake’s skin condition cleared within 10 days.
An excellent article on the unique Aquatic Garter Snake, including habitat photos, is posted here.