Do Garter Snakes Eat Slugs?

Conventional wisdom (MARAP, Mass Wildlife, latest issue) has it that garter snakes eat slugs. I’ve never been able to confirm this, and I have even noted a garter snake that inadvertently mouthed a slug and appeared to be very distressed about his predicament and tried to wipe the slime off. This little photo sequence suggests that garter snakes prefer worms. This was on my front doorstep where i experiment with snakes, as they like to hide under the junction, with their head sticking out. I first tried to feed a slug to the snake, by coaxing the slug to crawl in front of the snake. I tried this twice, being careful not to disturb the snake. No luck. I next tried a worm. This I had to do twice also because the worm crawled off the step. On the second try the worm was upset and wriggled more, which seemed to interest the snake and precipitate feeding.

The garter snake eyes the slug.

And it eyes the worm…