Eastern Garter Snake (Thamnophis sirtalis) Care Sheet

Eastern Garter Snake (Thamnophis sirtalis) Care Sheet

​A complete guide for the successful keeping of this active, diurnal, and semi-aquatic snake, known for its tolerance to cooler temperatures and unique diet.

​1. Overview & Commitment

  • Common Name: Garter Snake, Garden Snake

  • Scientific Name: Thamnophis sirtalis spp.

  • Natural Habitat: Highly adaptable, found near permanent water sources (ponds, streams) across North America. They are active, semi-aquatic, and primarily diurnal.

  • Size: Small to medium, typically reaching 0.6 – 1.2 m (2 – 4 feet) in length.

  • Lifespan: 10 – 20 years in captivity.

  • Temperament: Extremely active, curious, and fast-moving. They may musk or strike when first handled, but usually tame quickly. They can be housed communally (females or mixed groups, provided they are fed separately).

​2. Vivarium/Enclosure

​Garter snakes require a habitat that is both long for active movement and provides access to water.

  • Minimum Adult Enclosure (Pair/Trio): A standard 75-gallon (1.2 m / 4 ft long) enclosure or equivalent is recommended for a pair or small group, emphasizing floor space.

  • Enclosure Type: Secure glass or PVC enclosure. They are excellent escape artists, so the lid must be securely clamped.

  • Structure: Provide multiple horizontal climbing branches, artificial or live plants for cover, and two hides (warm and cool).

  • Water Feature (Crucial): A large, sturdy water dish or shallow water basin must be provided for soaking, swimming, and drinking.

​3. Substrate

​The substrate must be safe, easily cleaned, and moisture-tolerant due to the water feature.

  • Recommended Substrate: A layer of Cypress Mulch, Coconut Fiber (Coco Coir), or a soil/sand mix.

  • Management: Keep the substrate damp around the water feature but drier on the basking side. Spot-clean immediately, as they have a fast metabolism.

​4. Heating & Temperature

​Garter snakes are cool-tolerant but still require a heat gradient.

  • Primary Heat Source: An overhead basking lamp or Ceramic Heat Emitter (CHE) connected to a Thermostat.

  • Basking Spot/Hot Spot: A surface temperature of 30°C – 32°C (86°F – 90°F) is necessary for digestion.

  • Cool Side Ambient: 21°C – 24°C (70°F – 75°F).

  • Night Time: Temperatures can safely drop to 18°C – 21°C (65°F – 70°F).

​5. Lighting & UV

  • Ambient Light: Full-spectrum LED lighting to support their diurnal nature.

  • UVB (Recommended): A low-level UVB source (e.g., a 5-6% T5 tube) is highly beneficial, as they bask frequently in the wild.

  • Photoperiod: Maintain a consistent 12-hour cycle.

​6. Humidity & Hydration

​Moderate humidity is required, achieved easily with the large water dish.

  • Ambient Humidity: Generally requires a moderate level of 50% – 70%.

  • Water Quality: The large water dish must be kept impeccably clean and fresh daily.

​7. Diet & Feeding

​Garter snakes are unique in that they primarily eat fish, worms, and amphibians in the wild.

  • Staple Diet: A varied diet is key. Frozen/thawed Silversides, Tilapia fillets, or Salmon fillets (cut into strips). Live Earthworms (bait shop worms, not garden worms) are excellent.

  • Supplemental: Appropriately sized frozen/thawed mice or rat pups can be offered occasionally (once every few weeks) to provide variety and fat.

  • Warning (Thiaminase): Avoid feeder fish that contain high levels of thiaminase (e.g., gold fish, feeder guppies, rosy reds) as this enzyme destroys Vitamin B1 (Thiamine), leading to neurological issues. Stick to Thiaminase-free fish (Silversides, Tilapia).

  • Feeding Schedule (Adult): Feed 2–3 times per week due to their fast metabolism.

​8. Handling & Maintenance

  • Handling: Frequent, gentle handling usually calms them down quickly. Be aware of the initial musking when young.

  • Maintenance: Daily spot cleaning is required due to their fast metabolism and watery waste. Clean the water dish daily.

  • Communal Housing: If housing communally, ensure each snake is fed individually (with tongs, separated if necessary) to prevent fighting or cannibalism.