Monkeys of Makokou features mixed-species habitats for drills, mona monkeys (mona guenons) and Wolf’s guenons. Lush foliage and large, man-made trees offer the animals ample opportunities for foraging and climbing.

Drill monkey (Mandrillus leucophaeus)
Zoo Atlanta is one of only a handful of zoos housing these highly endangered, forest-dwelling monkeys. To date, this species has reproduced only at Zoo Atlanta and the Los Angeles Zoo. Zoo Atlanta’s drills have produced seven offspring, all of which have been mother-reared. Like many primates, drills learn vital survival skills and natural behaviors from their parents.

Range and Habitat
Drills occupy a very restricted range and are found primarily in coastal forests in western Cameroon, eastern Nigeria and the West African island of Bioko. Drills are primarily terrestrial but will climb trees to obtain fruit.

Physical Characteristics
Males are much larger than females, weighing 80 to 110 pounds. (Females tip the scales at a considerably smaller 30 to 40 pounds.) Males have canine teeth that rival those of big cats in length (1.5 to 2 inches long). These teeth are used for dominance displays rather than for eating.

Diet
Wild diet includes plant matter, insects and small invertebrates.

Behavior

• Drills live in family troops of 20 or more animals. Troops are led by a dominant male, who retains his status until successfully challenged by another male.

• Unlike great apes, drills do not walk on their knuckles, using the flat surfaces of their feet and hands instead.

• Drills can often be seen grooming one another; this is an important part of social life and reinforces hierarchy within the group while helping to keep the animals parasite-free.

Life Span
30 years. Females are sexually mature at 4 to 5 years; males, 5 to 7 years.