Snakes in captivity are invariably fed too much. Keepers, particularly novices used to mammalian metabolisms, have a hard time grasping the concept that even once a week may lead to obesity. I’ve seen some hideously overweight snakes, with a thick layer of fat outside their rib cages. Snakes have low metabolisms, and in captivity they don’t exactly exercise much.
Our snakes are not overfed. This is as much a function of weekly feedings being stretched out to every 10 to 14 days as a result of scheduling as it is by design, but either way it works. Overall, I’m pleased with our snakes’ condition: they’re mostly lean and muscular, with little or no fat.
Even so, our glossy snake is looking heftier than she should, and that’s probably a result of her diet — not the amount or the frequency, but the kind. Glossy snakes normally feed on lizards in the wild, though they’re not strict specialists; in captivity they can and will take rodents, and ours has eaten nothing but since I got her in September 2001 (see previous entry). Generally, she’s preferred mice on the small size, and I think that’s because she’s not keen on fur: she ends up eating multiple pinky mice rather than larger sizes, though she’s been eating fuzzy mice (the next step up) recently.
I seem to recall (but cannot find the reference to it) that gray-banded kingsnakes — another lizard-eating species — that are kept long-term on a mouse diet accumulate serious fatty deposits. I wonder if that’s akin to what’s happening here. It’s not an unreasonable guess that a mouse diet is too rich for the glossy snake (though it doesn’t seem to be a problem for garter snakes; then again, they’re more active), though I don’t yet know what to do about it. (Lizards are not an option!) For the moment, I’ll try cutting her back some more and see if that helps.