Snakes eat snakes. When you have an excess of one it usually means its feeding on its prey and has plenty to eat..
This article kinda explains why I want no snakes on my property, if I can help it. If I had a bunch of garter snakes, then
I believe I would have a high concentration of poisonous snakes to feed them. I rarely see snakes any more, we tamed some wild ferrel
cats that hang around. They will attack a moving garden hose, lol.
Other familiar snake-eaters include the North American Kingsnakes (genus Lampropeltis), which have evolved resistance to the venom of many species of viper. Eastern Indigo Snakes (Drymarchon couperi) and their Central and South American relatives are also frequent snake eaters, and many other species of North American colubrids sometimes dine on each other, including Racers (Coluber constrictor), Coachwhips (genus Masticophis, now sometimes included in the racer genus Coluber), Garter and Ribbon Snakes (genus Thamnophis), and Coral Snakes (genus Micrurus). Among their prey are many of North America's venomous snakes, including the Copperhead (Agkistrodon contortrix), Cottonmouth (or water mocassin, Agkistrodon piscivorus), and many species of rattlesnake (genera Crotalus and Sistrurus), as well as many non-venomous species of snake. Because all snakes are predatory, the existence of snake-eating snakes implies that some snakes are feeding at a very high trophic level indeed, and indeed they may represent top predators in some ecosystems.
Doug