Rat Snake — care sheet

Beginner. Hardy, forgiving, and eats readily, which makes rat snakes a genuinely good first big colubrid. The one catch is size: adults are long, strong, semi-arboreal escape artists, so you need a properly large, well-secured enclosure and a steady hand. Get the space and the lid right and the rest is easy.

Strict carnivore: appropriately sized frozen-thawed rodents (mice graduating to rats as the snake grows). Feed adults roughly every 7–14 days; juveniles every 5–7 days. Prey should be no wider than about 1–1.5x the thickest part of the snake's body.

Minimum for one adult is 6'L x 3'W x 3'H (about 180 x 90 x 90 cm) of floor space — bigger is always better. Because rat snakes are strong climbers, height and branches are used, and a tightly locking, escape-proof lid is non-negotiable.

Warm hotspot 85–90°F (29–32°C), created with an overhead heat source on a thermostat.

72–77°F (22–25°C) at the cool end, giving the snake a full thermal gradient to choose from.

Turn heat off at night and let the enclosure cool to normal room temperature (roughly 70–75°F / 21–24°C is fine); no night heat is needed unless your room drops below the low 60s°F.

Low-need, not no-need. Rat snakes can survive without UVB, but modern best practice is a low-output UVB tube because it supports better welfare and D3/calcium metabolism. A T5 HO 5–6% bulb (Zoo Med Reptisun 5.0 or Arcadia Forest 6%) aimed at the basking zone for a UVI of about 2.0–3.0, mounted ~12–14 inches above the snake with no mesh blocking it.

Average 50–70%, measured with a digital probe hygrometer placed in the middle of the enclosure. A brief bump toward the higher end helps during shed.

A loose, moisture-holding substrate about 4 inches (10 cm) deep for burrowing — soil-based mixes or plantation soil work well. Aspen or cypress mulch are also common. Avoid cedar and pine, which give off harmful oils.

A varied whole-prey rodent diet is nutritionally complete, so routine dusting isn't usually required. If you keep UVB modest or absent, a light occasional calcium-with-D3 dust on prey is a reasonable insurance policy — ask your exotics vet what fits your setup.

3.5–6 ft (1.1–1.8 m) is typical, with large individuals reaching ~8.5 ft (2.6 m). A long, powerful colubrid — plan enclosure space for a snake well over a metre.

15+ years in captivity; well-kept individuals have lived 16 to nearly 34 years.

See a reptile or exotics vet if you notice: Open-mouth breathing, wheezing, clicking or gurgling sounds, or bubbles/mucus around the mouth or nostrils — possible respiratory infection; see an exotics vet promptly.; Redness, swelling, cheesy discharge, or pinpoint bleeding around the mouth/gums — possible mouth rot (infectious stomatitis); needs a vet.; Repeated incomplete sheds or retained eye caps (spectacles) — often a humidity/husbandry issue that can trap infection; get it addressed.; Tiny moving black or red dots on the snake or in the water bowl — snake mites; treat and see a vet if it persists.; Prolonged refusal to eat with weight loss, lethargy, or a visibly thinning body — have an exotics vet rule out illness before assuming it's seasonal..