Black And White Colobus Monkey

Black and White Colobus Monkey

Black and white colobus monkeys are excellent jumpers – they routinely jump 45 to 50 feet between trees. When under threat, however, they can jump in excess of 60 feet. The name “colobus” is derived from the Greek word for “mutilated,” a reference to the monkey’s lack of a thumb. African legend calls the black and white colobus monkey “the messenger of the gods” because they often sit facing the sun at sunrise, and appear as though they are in prayer.

Physical Traits
Black and white colobus monkeys have slender bodies with a long tail. Extended nasal skin nearly reaches the mouth, making the nose look like a bulb. Most of the body is black, except for a fringe of white fur running in a lateral line from the neck to the tail. The tail is covered in long white hair. Males are usually larger than the females, but otherwise the two sexes are very similar in appearance.

While many primates have a fifth digit – a “thumb” – the black and white colobus monkey only has four digits on each hand. The thumb is either absent or represented by a small phalangeal tubercle which sometimes bears a nail.

The colobus is arboreal and only rarely descends to the ground. It uses branches as trampolines to leap up to 50 feet across. Their mantle hair and tails are believed to act as a parachute during these long leaps.
Colobus monkeys live in troops of about five to 10 animals—a dominant male, several females and young. Each troop has its own territory which is well defined and defended from other troops. Adult troop members, especially males, make croaking roars that can be heard resonating throughout the forest.
Fighting over mates rarely occurs. There is no distinct breeding season although most mating probably occurs during rainy season. Because a female suckles her infant for over a year, an average of 20 months passes before she gives birth again. Other troop members often handle very young infants. In the first month when the infant still has a pink face, it may be handled three to five times an hour in resting groups. Infant mortality is high even though the young are carefully tended.

The newborn colobus monkey is covered with white fur, and at about 1 month gradually begins to change color, finally gaining the black and white adult coloration at about 3 months. The infant monkey is carried on the mother's abdomen, where it clings to her fur. As it matures it spends a lot of time playing with its mother and certain other adults and at about 7 months begins playing with other juveniles. The games they play exercise their bodies, and as they get older, these develop into wrestling matches and mock displays.

Adaptations
Black and white colobus monkeys have developed a two-compartment stomach that functions similar to the stomachs of ruminant animals such as cows. Since the monkeys consume so much plant fiber, the two-compartment stomachs give the plant material more time to be broken down by the digestive system.

Reproduction and Growth
Full sexual maturity is reached at about 6 years for males and 4 years for females. There is little to no reproductive seasonality for the black and white colobus monkey and the mating system is polygamous. Pairs mate for 12 to 24 hours, away from the rest of the group.

Sexual activity is usually initiated by the female, through a behavior known as tongue smacking. Gestation lasts for about 6 months, and babies are completely white when they are born.

At birth, the eyes are open and the babies cling to the mother or father’s stomach while the group moves about in the trees. Female black and white colobus monkeys remain with the troop they were born to, meaning that mothers have life-long relationships with their daughters.

Diet
Black and white colobus monkeys eat a variety of leaves, and just three tree species comprise almost 70% of their diet. Most commonly, colobus monkeys prefer to eat leaves from trees that are deciduous and found at the edge of the forest. Fruits and flowers are also eaten, though much less commonly than leaves.

Social Organization
The size of a troop of black and white colobus monkeys ranges anywhere from 3 to 15 individuals. Most often, a troop is made up of a single adult male, three or four adult females, sub-adults, juveniles, and infants.

Groups with multiple adult males as well as groups made up of bachelor males have been observed, but it is believed that these groups are only temporary.

Colobus monkey troops are highly social, and members of a troop will often share the responsibility of caring for infants.

Conservation Connection
Numbers of black and white colobus monkeys have declined drastically in the last 100 years due to a variety of factors. The 19th century saw an explosion in the fur trade, and colobus pelts were popular on the fur market. In more recent years, rapid human population growth and the increase in the bushmeat trade have caused population declines for this species