Bushbabies: Galagidae

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BUSHBABIES: Galagidae

SENEGAL BUSHBABY (Galago senegalensis): SPECIES ACCOUNTS
NORTHERN GREATER BUSHBABY (Otolemur garnettii): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

The largest bushbaby is the brown greater bushbaby. An adult male weighs 3.1 pounds (1.4 kilograms). Body length is 12.5 inches (31.5 centimeters) with a 16.5-inch (41-centimeter) tail. The smallest bushbaby is the mouse-size Demidoff's bushbaby. An adult male weighs 2.5 ounces (65 grams). Its body is 5 inches (13 centimeters) long, with a 7-inch (18-centimeter) tail. Females are somewhat smaller than males.

Bushbabies are usually gray, reddish, or brown with lighter underparts, having gray or dark eye patches. Their fur is thick and soft, and larger bushbabies have quite long bushy tails that help them balance. All bushbabies have rounded heads, short pointed faces with forward-facing eyes, and a pointed snout, or nose area. They can rotate their head in a full circle. Their ears individually bend backward or wrinkle forward, enabling them to better locate sounds. Bushbabies have a special reflective, or mirror-like layer at the back of their retina, or light-receiving, part of the eye. This lets them see in extremely dim light. It also makes their eyes shine in the dark, like a cat's eye.

Bushbabies have larger hindlegs, or back legs, than forelimbs, or front legs. Very strong hindlegs and very long anklebones enable most species to move extremely quickly and accurately. A bushbaby's hands and feet have five long slim fingers, or digits, on each forelimb and five long, slim toes on each hindlimb. Their fingertips have round flat pads of thickened skin that help them grip firmly onto branches. All digits have nails, except the second digit of the hind foot, which has a long curved claw for grooming or cleaning. For grooming, bushbabies also use their lower incisors, or front teeth, and pointed canine teeth as a toothcomb. Underneath the tongue is a false-tongue, which is used to clean the toothcomb.

GEOGRAPHIC RANGE

Bushbabies are found in many parts of Africa, from sea level to 6,000 feet (1,800 meters).

HABITAT

Bushbabies live in many areas, from dry, thorny scrub to evergreen tropical rainforests.

DIET

Depending on the species, bushbabies usually eat fruit, gum or plant fluids, and insects. They can find insects by sound alone and snatch them from the air as they fly past.

BEHAVIOR AND REPRODUCTION

Bushbabies are nocturnal, searching for food at night. They usually remain in trees, but occasionally travel on the ground. Most leap from branch to branch. Some can leap long distances from one branch to another. Others hop on their strong hind legs between branch supports. Some can hang onto vertical supports, such as tree trunks. While most move quickly, the thick-tailed bushbaby sometimes moves very slowly and quietly.

Bushbabies usually sleep in social groups of eight to twenty members. During the day, they rest in hollow trees, tree forks, or old bird nests. Some make sleeping nests from leaves. In a few species, a mated pair and their young may sleep together. In other groups, the adult male does not sleep in the group-sleeping nest. He keeps in contact with females when they are outside the sleeping nest.

SOUNDING OFF

The common name bushbaby comes from their loud wailing territorial sound, which sounds somewhat like a human baby crying. Bushbabies make a variety of different sounds, as well. The Senegal bushbaby makes a high-pitched scream when upset, has an alarm call which includes grunting, clucking, whistling, wailing, and sneezing, as well as grunts when it is ready to fight. Infants call to their mothers with a "tsic" sound, and mothers reply with a cooing or soft hooting sound.

Bushbabies forage, or search for food, by themselves. Males have larger territories, or feeding areas, than females. These often overlap those of several female groups. Scent, sounds, and facial expressions all play a role in bushbaby communication.

An adult male bushbaby may mate with several females. Twice a year, one to three infants are born. The young are fully furred with their eyes open at birth. Bushbaby young spend a week or longer in a hidden tree nest. The mother may leave them there while searching for food, or she may travel, carrying her young in her mouth. When she eats, these babies are placed to cling onto branches. Later, bushbaby young may ride on their mother's back as she searches for food. A baby is weaned, or stops feeding on breastmilk, at about two months of age. It becomes independent at about four months of age. Females may remain in their birth area or travel to new areas.

BUSHBABIES AND PEOPLE

Bushbabies are often captured by local people as pets. The larger species may be used as food or killed for their fur. Bushbabies may also be taken for zoo exhibits. Bushbabies can be carriers for the yellow fever virus. Mosquitoes feeding on them can transmit the disease to humans.

CONSERVATION STATUS

Most species are common in Africa. However one species is Endangered, facing a very high risk of extinction, and six are Near Threatened, not threatened, but could become so, due to habitat, or living area, destruction.

SENEGAL BUSHBABY (Galago senegalensis): SPECIES ACCOUNTS

Physical characteristics: The Senegal bushbaby is also known as a lesser galago or lesser bushbaby. It is gray with yellowish highlights. It has soft, thick fur. Its large eyes are surrounded by thick dark eye-rings. It has very large, moveable ears. A bushbaby can rotate its head in a circle, like an owl. The Senegal bushbaby is 6.5 inches long (16.5 centimeters) with a 10.5-inch (26-centimeter) tail. Adult males weigh 11 ounces (315 grams), with adult females being slightly smaller.


Geographic range: Senegal bushbabies are found in sub-Saharan Africa, from Senegal to Kenya.


Habitat: Senegal bushbabies live in dry forests, thorny scrublands, and grasslands with some trees.

Diet: Senegal bushbabies usually feed on the gum, or liquid, from acacia (uh-KAY-shah) trees and insects.


Behavior and reproduction: Senegal bushbabies are nocturnal, moving about at night. They usually stay in trees, hanging vertically, or up and down, on tree trunks. They move by making long leaps from branch to branch, up to 10 to 13 feet (about 4 meters). They also can kangaroo-hop on the ground.

A Senegal bushbaby adult male may mate with several females. Females give birth twice a year and are pregnant for about four months. The pregnant mother prepares a leafy birthing nest. Babies weigh about 0.42 ounces (12 grams) at birth. Mothers nurse babies for about three months. For the first few weeks, the infants cling to the mother's fur as she travels. Young males leave their parents at about ten months of age, but females may stay longer. They are ready to have a litter by twelve months of age.


Senegal bushbabies and people: Senegal bushbabies play a small part in the lives of local people.


Conservation status: Senegal bushbabies are not currently endangered, but may become threatened by habitat loss due to land clearing for farming purposes. ∎

NORTHERN GREATER BUSHBABY (Otolemur garnettii): SPECIES ACCOUNTS

Physical characteristics: The northern greater bushbaby, also known as Garnett's bushbaby, Garnett's galago, small-eared galago, or greater bushbaby, has reddish to grayish brown fur. It lacks facial markings and has very large, light-sensitive eyes. At night, the pupil opens into a complete circle to allow for better vision in the dark. Adult males weigh 1.75 pounds (795 grams) with females slightly smaller. Body length, including the head, is 10.5 inches (26.5 centimeters), and they have a 14.5-inch (36.5-centimeter) long bushy tail.


Geographic range: Northern greater bushbabies are found in northeastern Africa.

Habitat: Northern greater bushbabies live in coastal and highland forests.


Diet: The northern greater bushbaby usually feeds on fruits and insects.


Behavior and reproduction: The northern greater bushbaby adult male may mate with several females. Adult females give birth to one or two infants at a time. They are pregnant for eighteen weeks. Until two weeks of age, the babies stay in a leafy nest. They then cling to the mother's fur as she travels searching for food.

The northern greater bushbaby runs and walks on all four limbs along tree branches, following regular pathways. Occasionally it searches for food on the ground, where it may hop like a kangaroo, or jump-run, hopping first on hind legs, then on forelegs. It hides during the day to avoid predators, such as large snakes.

Northern greater bushbaby males and females often share feeding territories as well as nests. However they usually feed alone at night. Adult males will tolerate younger or lesser males within their feeding range. During the day, these bushbabies return to tree hollows or vine tangles to sleep as a group.


Northern greater bushbabies and people: Northern greater bushbabies have no known interaction with people.


Conservation status: These bushbabies are rather common and not immediately threatened. ∎

FOR MORE INFORMATION

Books:

Alden, Peter C. National Audubon Society Field Guide to African Wildlife. New York: Alfred A. Knopf, 1995.

Coppard, Kit. Africa's Animal Kingdom. London: PRC Publishing Ltd, 2001.

Kennaway, Adrienne. Bushbaby. Manningtree, U.K.: Happy Cat Books, 2002.

Maynard, Thane. Primates: Apes, Monkeys, and Prosimians. Danbury, CT: Franklin Watts, 1999.

Ricciuti, Edward R., and Bruce S. Glassman. What on Earth is a Galago? Woodbridge, CT: Blackbirch Press, 1995.

Sleeper, Barbara. Primates. San Francisco, CA: Chronicle Books, 1997.

Stevenson, William. Bushbabies. Boston: Houghton Mifflin Co., 1980.

Periodicals:

Bearder, Simon K. "Calls of the Wild." Natural History (August 1995): 48–58.

Churchman, Deborah. "Meet the Primates!" Ranger Rick 31, no. 10 (October 1997).

"Monkeyshines on the Primates." Monkeyshines Publications (1994): 39.

Stewart, Doug. "Prosimians Find a Home Far From Home." National Wildlife (Feb/Mar 1998): 33–35.

"Wildlife of Tropical Rain Forests." National Geographic World (January 2000): 22–25.

Web sites:

Animal Diversity Web. "Galagonidae." http://www.primates.com/primate/galagonidae.html (accessed on June 23, 2004).

The Chaffee Zoo. "Lesser Bush Baby." http://www.chaffeezoo.org/animals/bushbaby.html (accessed on June 23, 2004).

Singapore Zoo Docent. "Galagos or Bushbabies." http://www.szgdocent.org/pp/p-galago.htm (accessed on June 23, 2004).