Allen's swamp monkeys are strong and stocky with gray/green fur and webbed fingers and toes. Their face is reddish, with patches of long hair on their cheeks They live in the swamp forests of Central Africa. Male swamp monkeys are larger than females. While they spend a lot of time in trees, they also forage for food on the ground. Their webbed fingers and toes help make them good swimmers—they may even dive into water to avoid predators. Water may also mean food, as Allen swamp monkeys "go fishing" for food by placing leaves or grass on the surface of the water and then grab the fish that come to hide under it.