Fish as Predators
If you need to control an over population of snails in your pond, adding certain species of fish can help minimize the problem. Redear Sunfish will readily eat pond snails, according to the Ohio State University Extension. Common carp, koi and large goldfish will also feed on pond snails, especially newly hatched snails with soft shells. Yellow perch, channel catfish, yellow bullhead and Eastern mosquito fish also prey on pond snails.
Occasional pond visitors can cause the snail population in your backyard pond to dwindle. Watch for raccoons, bald eagles and muskrats, all of which eat snails. Other animals that prey upon snails include ducks, mallards, American eels, cormorants, cranes and water-dwelling bird species.
Reptiles and Snails
Some reptiles will include snails in their diets. Eastern painted turtles, American alligators, Chinese alligators, Yacare caimans and Morelet's crocodiles that live in ponds also hunt for snails to add variety to their protein-rich diets.
Amphibians and Insects
Small snails and the jelly-like sacks of snail eggs attached to foliage in and around the water's edge provide nutrition for frogs, salamanders, Eastern newts, tadpoles and leeches. Even small creatures such as dragonflies, beetles and other pond insects dine on snail eggs attached to floating pond moss, lily pads and driftwood.