After another 2 years they are 4 to 5 inches long and begin to breed. They have been known to live 15 years in captivity. Bullfrogs have a host of enemies. Little tadpoles are preyed upon by water beetles, water bugs and fish. Larger tadpoles and adults are eaten by larger fish, water snakes, herons and other water birds, snapping turtles, raccoons, mink, skunks and owls, but man is their worst enemy.
Schools use a half-million bullfrogs annually in biology courses.
As a result, most states have closed seasons and other restrictions on bullfrog hunting. Try sitting quietly for at least a half-hour near a pond or marsh. It's good medicine, and there's no telling what you may see and hear. Argonne National Laboratory, Division of Educational Programs, Harold Myron, Ph.D., Division Director.