The Indians would make long wooded blowguns with darts in them for hunting. Then they killed the frogs to get their poison. They would then put the poison on the end of their arrow to go hunting. Some frogs are cannibals. That means they eat other frogs.
Snakes eat frogs too.
Bullfrogs eat mice and other small frogs. Bullfrogs may lay about 50,000 eggs. Frogs hibernate in the winter when it is too cold. They swim to the bottom of ponds and lakes and hide under mud and leaves at the bottom. Their body almost completely stops so they don't need as much air.