Snake feeding time at our house is always hilarious. The boas always seem to constrict their mice, which are always previously frozen and thawed, for twenty minutes before they try to eat them, and the kingsnakes I’ve had have been so stupid they occasionally bite themselves instead of the mouse. But the garter snakes have never failed to be a source of great entertainment whenever mice are dropped in their cages.
My adult male Red-sided Garter Snake (Thamnophis sirtalis parietalis), for example, never seems to notice the mouse going in the cage. He gets so worked up by the smell of the tasty rodent that he strikes repeatedly and frantically against the front of his cage. Instead of going after the mouse, he follows the movement taking place outside his cage — which is to say, us, as we move on to the next snake to feed. Eventually he finds it, but sometimes he’s so worked up that we have to leave the room, or lead him along, wiggling our fingers along the cage in hopes that he will stumble across — and maybe even acknowledge — the mouse we’ve left in there for him. His kids — we still have two males and a female from our 2002 litter — are no better.
Tease-feeding garter snakes — which is to say, offering the food to them with a set of tongs, and wiggling it a little — doesn’t seem to work any better. During one recent feeding session, my adult female Wandering Garter Snake (Thamnophis elegans vagrans) was offered a worm-scented mouse using a pair of hemostats. Like my red-sided male, she had a great deal of trouble hitting the target: she struck wildly, inaccurately, and frequently at the hemostats themselves rather than at the mouse. (Good thing it was hemostats rather than fingers!) The same thing also happened recently with my ancient1 female Butler’s Garter Snake (Thamnophis butleri), who struck at the hemostats, rather than the mouse, with equal enthusiasm.
It occurred to me then that, for the most part, you really can’t tease-feed a garter snake.2 Why is this the case? After all, most other snakes kept in captivity don’t have a problem taking food from a set of tongs — some even need it.
But, unlike other snakes kept in captivity, garter snakes are both active hunters (rather than ambush predators who lie in wait for prey to pass by, rather than hunting it down) and visual — they use their eyes more than other snakes do. Which is not to say that their Jacobsen’s organ isn’t being put to use — just look at that flick rate — but that, in addition to smelling, they’re also watching. In my experience, they’re extremely keyed to motion — which raises another point.
Several of my garter snakes have proved difficult to feed not because, I suspect, they were reluctant to eat mice, but because they were reluctant to eat food that did not move. Frozen, thawed mice — the standard diet of just about every snake in my care — did nothing for them. They ignored fish fillet, and would probably have ignored whole dead fish too. If they took worms, they wanted a whole, live nightcrawler, not worm pieces (which made it problematic if it was a snake too small to take one of those enormous bait-store nightcrawlers, generally the only kind I had on hand).
But live fish? Gone within minutes. This was a problem, because it made it more difficult to keep these snakes healthy; live feeder fish can be loaded with parasites, and I lost a large number of snakes as a result.
So of course I wanted to get them to take mice as soon as possible. If they were visually attuned, if they needed to see their food move to recognize it as food, then I would have to offer it on tongs, and tease-feed it to them.
Except, of course, you can’t tease-feed a garter snake. They reacted — often negatively — to the motion, striking at the tongs as much as at the mouse. One particularly jumpy snake — a beautiful but psychotic Eastern Black-necked Garter Snake (Thamnophis cyrtopsis ocellatus) — wanted it both ways: she wanted her food to move, but was so freaked out by our presence that she wouldn’t eat food off the tongs. (She ate nothing but live fish, and was found dead in her cage after a year.)
That garter snakes react to motion is an asset in the wild, but it does make it somewhat more of a challenge in captivity — especially if they need their food to move, but react to what’s moving it instead of the food itself. Your mileage may vary, of course, and some snakes are less freaked out than others.
Update (Nov. 29, 2006)
Your mileage may definitely vary. Roy Mellott Jr. writes that he has no trouble tease-feeding his garter snakes:
I have two T. s. concinnus that I tease feed with great success. My wild caught male won’t take a mouse that’s just laid in the tank. I have to offer it on forceps and he hits his target every time, with out fail and with much vigor! My female is a VERY aggressive feeder and I’ve actually had to use the mouse to get her back into the tank when she’s come rocketing out of it for food. She also always hits the mouse first shot, once she’s spotted it. Just thought I’d add my differing experience with tease-feeding.
Remember that each snake is an individual, and that my experiences may not be the norm.