Allen’s swamp monkeys “go fishing” by laying leaves or grass on top of the water, and grabbing fish that come to hide underneath. As their name implies, swamp monkeys live near water and are good swimmers. They have been known to dive into the water to escape predators. Allen's swamp monkey has a sturdy build and gray/green skin. The face is reddish with long hair bundles at the cheeks.
This monkey likes company! The average group size is around 40 individuals. These large groups are divided into sub-groups of two to six monkeys who work together foraging for food. The groups' sleeping sites are usually located near water, and become regular spots and repeatedly used. Individuals will groom each other to remove dead skin and parasites. This kind of behaviorIn biology, an organism's activity in response to its environment. The study of animal behavior is called ethology. reinforces bonds between two individuals.
Allen's swamp monkeys make a grunting sound that is used to maintain contact between members of the group.