[z10silver]

Yes - Terry generously donated all of the snakes for the study (which have since been released). I am still busy researching/analyzing the data I've obtained, but here is a brief summary of the results:

For the experiment, I divided a litter of 37 newborn
T. s. sirtalis into three groups. (All snakes housed
individually) One group was fed earthworms, one was
fed fathead minnows, and the other was fed an
alternating worm/fish diet. The snakes were offered
an excess (weighed) of food items chopped into small
pieces. The snakes were weighed before and after
eating to determine (approx.) how much food was eaten.
At the end of the study (5 weeks) the diets of the
worm group and the fish group were reversed.

I found that all snakes in the worm group ate at every
feeding, and consumed a higher avg. weight of food
than snakes in the fish diet.

Of the 12 snakes in the fish group, 10 snakes ate
regularly, while 2 refused food after the initially
feeding.

Of the 12 snakes in the worm/fish diet, all consumed
worms at the initial feeding. However, when offered
fish, 4 snakes would not eat. This trend continued.
In sequential offerings of fish, between 6 and 9 of
the snakes would not eat. Interestingly, the snakes
seemed to have developed a modified feeding pattern to
compensate. On days when they were given worms, the
snakes in the worm/fish group consumed significantly
more worms than the snakes in the worm group. The
snakes in the worm/fish group that did consume fish
ate significantly less than snakes in the fish group.

This result supports previous studies that have shown that exposure to certain prey items (in this case worms) can inhibit the response to other prey (minnows).


However, I am unsure if this
accounts entirely for the observed results. (2 snakes refused fish after initally consuming it) Studies have
shown that garter snakes may be conditioned to avoid
prey that induces illness. I am curious if
thiaminase could play a role in the conditioning of
the snakes to avoid minnows.

-Zach Cava