The bullfrog is one of the most widely distributed frogs across the North American continent. The bullfrog is a medium-sized frog that is best known for it's loud cow-like calls, hence it's name. Bullfrogs are found in a wide range of permanent freshwater habitats including ponds, swamps and lakes where the bullfrog tends to prefer to be closer to the banks rather than out in the open water. Bullfrogs also prefer to be in warmer climates rather than the cooler ones .