You can also feed silversides. Do some research on which ones you are buying tho. Make sure it doesn't contain Thiaminaise. The package won't tell you. Most if not all garter snakes enjoy fish from time to time. Some people even make prepared diets for them. Cool little snakes.
They are also mildly venomous, and while it doesn't pose any general health risks to humans there is an off chance that you can be allergic to it so just be cautious. Don't let them gnaw on you if they bite lol.
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