Drill/Mandrillus leucophaeus:

Credit to College's Bioko Primate Protecdtion Program (http://bioko.beaver.edu/primates/leucophaeus.html)

Height:The male has a head and body of about 61.0 to 76.4 cm in length, with a tail length of about 5.2 to 7.6cm.

Weight: The average body mass for an adult male drill is about 25kg while the average body mass for an adult female drill is about 11.5kg.

Distribution: The drill is found in the countries of Equatorial Guinea, Cameroon and Nigeria and in the moist evergreen forests of Bioko and between the Cross and Sanaga rivers. They live in the Cameroon mountains up to 1,000 m and also in areas with both forest and savannah components. This species lives in mature primary forests which are either riverine or rainforest

Appearance: The drill looks like a stocky, olive-brown baboon with a large head, an off-white underside, and a white ruff surrounding a hairless black face. Dense fur around the neck of the adult male greatly enlargens the look of its head and chest. The bright red chin of fully adult males stands out from many of the other primates, making it easy to spot. The impressive pink, blue, and mauve buttocks top a bright red scrotum. The anterior region of the scrotum of the male is colored pink and the posterior region is a lilac color while the region around the anus is colored red. The glans penis of the male is colored pink. This is a sexually dimorphic species and there are swells on either side of the nasal area, pronounced maxillary ridges. A stubby tail appears above the buttocks. The hands and feet are broad and strong, well adapted to live in the harsh conditions of the dense rainforests.

Behavior: Drills usually live in groups of up to 25, sometimes multiple groups form bands of up to 200 animals. The groups consist of a single dominant adult male and multiple females and their offspring. Groups travel on the ground as far as 12 miles for food, but feed and sleep in the trees.

While foraging, drills utter a sharp alarm bark and grunt. Other sounds include the marked crowing call for contact between groups and the croaking call of distressed juveniles. The dominant male will shake branches and bob his head as a threat display.

Tension yawning is done by an adult male drill when a rival group or a predator is approaching. This is done when the mouth is opened fully to reveal the canines. A threat jerk is also done by drills as a threat display. The head is jerked forward, while the eyelids are retracted, the medial crest is raised, and the lips are compressed forward. This is done sitting or standing.

Credit to College's Bioko Primate Protecdtion Program (http://bioko..edu/primates/leucophaeus.html)

Diet: Drills are omnivores who eat fruits, much herbaceous growth, roots, mushrooms, invertebrates (especially worms, termites, ants, and spiders) and small vertebrates. Drills have also been reported to eat giant land snails, coconuts, sea turtle eggs, and infrequently injured duikers. This species mainly forages on the forest floor. Drills are a diurnal species and mostly a terrestrial species.

Credit to College's Bioko Primate Protecdtion Program (http://bioko..edu/primates/leucophaeus.html)

Reproduction: The drill gives birth to a single offspring. During estrus the perineum of the female swells up. Also during pregnancy the perineum turns red

Lifespan:One captive specimen lived for 34 years

Why is it endangered? The drill is now listed as Africa's most endangered primate. On the mainland, their range has been devastated by clear-felling and human settlement. They are hunted everywhere as bushmeat and it is not uncommon for an entire group to be shot as it takes refuge in the trees. The population on the southern tip of Bioko is one of only three known remaining populations.

Conservation: There are currently forty-six drills in zoos world wide, although most are in non-reproducing groups. In fact, only the small group of drills at the Hanover, Germany zoo reproduce regularly, with several females raising their young together.