Found throughout the United States, Mexico and Canada, Bull Snakes grow as long as 6 feet on average. Typically, they are yellow with brown, red or black splotching. They eat mammals such as mice, rabbits, squirrels, gophers and they even eat birds. When threatened, they rear up to look as big as possible before they lunge and back away at the same time. Their average lifespan is 18 years.