What do garter snakes eat?
The garden snakes feed on frogs and bugs that feed on the leaves of your plants in the garden. Younger garden snakes feed on worms that eats the stems and leaves of small plants. When they become larger they eat frogs, bugs, mice, and spiders in the garden. Humans are not included in their diet so your friends need not to worry about your garden snakes.
the real question is " what speicies of thamnophis is it " because their diet veries throught their range.
garters eat pinkie worms and slugs and the odd gold fish now and then at first then fuzzys and then mice
mice ,,rats, fruits,, grapes ,meat,