Gray-bellied Night Monkey

The gray-bellied night monkey (Aotus lemurinus), also called the lemurine owl monkey, is a small New World monkey of the family Aotidae. They are native to tropical and subtropical forests of South and Central America. The gray-bellied night monkey faces a significant threat from hunting. They are used in pharmaceutical research and habitat destruction.

Physical description

Like other members of their genus, this species is nocturnal. It has a small, round head. It is striped with black and is dominated by two large, brown eyes. The monkey’s eyes shine a reddish orange by reflected light. Its white eyebrows are bushy, with a patch of darker fur between them. Its gray fur is described as dense and woolly, with the animal’s belly being yellow to orange in color. Its brownish black to orange tail is not used to grasp and is invariably tipped with black.

The gray-bellied night monkey has slender limbs with long, delicate fingers. Its fingertip pads are wide. Adults may attain a weight of 2.87 lbs (1.3 kilograms).

Habitat and diet

Found in both dry and moist areas, the gray-bellied night monkey occupies all levels of the forest canopy. It is seldom found on the ground. It prefers dense vegetation with tangles of vines where the trees are evenly dispersed.

During the day, the monkey slumbers in the cavities of trees or in dense thickets. By night, it searches the canopy for a variety of food items. It is primarily fruit-eating. This monkey also eats vegetation, insects, nectar, and even other small mammals and birds when fruit is scarce.

Behavior and reproduction

It is most active during twilight hours and periods of bright moonlight. The gray-bellied night monkey troop consists of a mated pair and their offspring, up to five individuals in total. This species is noted for the monogamous pair bond it forms. Its parental duties are shared between the lead pair and the juveniles. It is the male who assumes the bulk of care giving and rearing responsibilities. The female serves only to nurse the infants. Remarkably, even if the male dies the female will refuse to take over from him.

The monkey produces a range of calls. They sound like soft clicks and low-pitched guttural rumblings to owl-like hoots and high-pitched shrieks when threatened. When not feeding, the monkey is typically inactive.

PHOTO CREDIT: The Primate Foundation of Panama