Mousebirds: Coliiformes

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MOUSEBIRDS: Coliiformes

BAR-BREASTED MOUSEBIRD (Colius striatus): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

The mousebird order received its name because the birds look like mice when they creep around on the ground and tree branches. Mousebirds have gray or brown plumage (feathers) and patches of other coloring. These birds, also known as colies (KOHL-eez), range in head-to-tail length from 10.2 to 15.7 inches (26 to 39.8 centimeters). Mousebirds' pointed tails make up more than half of that length.

Mousebirds have crests, clumps of feathers on their head. Birds have short red legs and feet. Mousebirds' small, curved bills are strong enough to break the skin off fruit.

GEOGRAPHIC RANGE

Mousebirds live in sub-Saharan Africa, in countries south of the Sahara Desert. Bar-breasted mousebirds range throughout most of that area. White-headed mousebirds live in Kenya and Tanzania. Chestnut-backed mousebirds live in the region of the Democratic Republic of the Congo and Angola. White-backed mousebirds and red-faced mousebirds live in southern Africa. Blue-naped mousebirds live in western, central, and eastern Africa.

HABITAT

Mousebirds live in forests where deciduous trees lose their leaves during dry or cold seasons. The birds live in grassland areas where there are fewer trees and grass grows. Some birds live in parks and in garden trees.

DIET

Mousebirds eat fruit, flowers, leaves, and buds. They sometimes eat insects.

BEHAVIOR AND REPRODUCTION

Mousebirds are social and noisy. They live in flocks of six to twenty-four birds. The birds are sedentary, not usually migrating from one area to another. During the day, birds eat, drink water, and take dust baths. Mousebirds travel in flocks to feed. Some birds climb to the top of a tree or bush to begin their flights. Birds fly quickly and land by crashing head-first into plants.

At night, a group of twenty or more birds roost (rest) in a tree. When the temperature drops, the birds enter a form of hibernation called torpor.

Mousebirds divide into pairs to breed. The birds are monogamous (muh-NAH-guh-mus), and breed with the same partner. The mousebird is an asynchronous (ay-SIN-kruh-nus) breeder, one that doesn't lay all eggs at the same time. The female lays a clutch of two to five eggs. However, sometimes there are seven eggs in a nest. The additional eggs usually belong to another female sharing the nest.

Mousebirds usually build nests in hidden places like leaf-covered branches or in thick bushes. The birds sometimes locate their nests near the nests of wasps, insects that have painful stings. Wasps provide protection against predators like snakes and larger birds. These predators hunt mousebirds for food.

After mousebirds breed, the male and female incubate the eggs, sitting on eggs to keep them warm. The mousebird's community behavior can extend to breeding. The couple that mated may be helped by "helper" birds. This is called cooperative breeding. Sometimes other males help guard the nest. These helpers are often the older offspring of the parents.

The eggs hatch in eleven to twelve days, and the birds fledge (grow flying feathers) within ten days to two weeks.

MOUSEBIRDS AND PEOPLE

Mousebirds damage trees, and that upsets people. They may poison or shoot the birds. Mousebirds sometimes die when pesticide is sprayed to kill insects. Not all birds are disliked; some people have bar-breasted mousebirds as cage birds.

CONSERVATION STATUS

Mousebirds are not in danger of extinction (dying out).

BAR-BREASTED MOUSEBIRD (Colius striatus): SPECIES ACCOUNT

Physical characteristics: Bar-breasted mousebirds, also called speckled mousebirds, have mostly brownish gray plumage, and their crests are the same color. The length of the long-tailed birds ranges from 10.2 to 14.2 inches (26 to 36 centimeters). Weight ranges from 1.3 to 2.8 ounces (36 to 80 grams).

The white-eared bar-breasted mousebirds of East Africa have white feathers on the sides of their heads. A subspecies in the northern range has a white spot on its upper mandible (jaw). Birds in one subspecies have bills that are black on top and pink on the bottom. Some groups of birds have white or blue marks on their bills.

Another difference is the color of the iris, the round part of the eye surrounding the pupil. Iris colors in subspecies include white, brown, and green. In addition, the iris may be two-toned, with the color above the pupil different from the color below it.

Geographic range: Bar-breasted mousebirds live in countries including Angola, Botswana, Cameroon, the Central African Republic, Eritrea, Ethiopia, Gabon, Mozambique, Nigeria, Somalia, Sudan, South Africa, Tanzania, Uganda, and Zimbabwe.

Habitat: Bar-breasted mousebirds live in grassland, deciduous forests, parks, gardens, and orchards where fruit trees grow.

Diet: Bar-breasted mousebirds eat fruit, berries, and plant buds and leaves. The type of food varies by habitat. Birds eat items native to an area along with fruits such as strawberries and tomatoes. The birds sometimes eat insects.

Behavior and reproduction: Bar-breasted mousebirds live in flocks of from six to thirty birds. The smaller group is usually a family of birds. Larger flocks consist of birds that look for food together and spend nights in the same trees. During the day, mousebirds feed and bathe. They also preen, cleaning their feathers with their beaks. At night, the flock roosts in tree branches.

Bar-breasted mousebirds can breed throughout the year. When birds breed depends on factors such as whether food is available to feed the young. During this season, birds pair off. The female lays one to five eggs. Both parents incubate the eggs.

The breeding pair may be helped by other birds. These cooperative breeders help with incubation and feeding. The helpers consist of one to three young birds of the same sex. Males are older offspring of the parents; females may not be related.

Bar-breasted mousebird eggs hatch in about twelve days, and chicks have yellow tongues. After the birds fledge, the parents may breed again. A female can lay up to eight clutches in a year.

Since mousebirds live in groups, this provides some protection from predators. Automobile drivers are a greater danger to bar-breasted mousebirds because the birds fly in a line one after the other. While flying in this pattern, drivers may accidentally kill the birds.

Bar-breasted mousebirds and people: People have various relationships with bar-breasted mousebirds. They sometimes resent the birds for ruining crops and taking fruit. People also admire the birds. The country of Gabon honored the bird with a 1992 stamp, and people in England bred captive mousebirds in 1912. Since then, people in countries including the United States keep bar-breasted mousebirds as cage, or captive, birds.

Conservation status: Bar-breasted mousebirds are not in danger of extinction. ∎

FOR MORE INFORMATION

Books:

del Hoyo, Josep, et al., eds. Handbook of the Birds of the World. Barcelona: Lynx Edicions, 1992.

Dickinson, Edward C., ed. The Howard and Moore Complete Checklist of the Birds of the World, 3rd ed. Princeton, NJ and Oxford, U.K.: Princeton University Press, 2003.

Forshaw, Joseph, ed. Encyclopedia of Birds, 2nd ed. San Diego, CA: Academic Press, 1998.

Harrison, Colin James Oliver. Birds of the World. London and New York: Dorling Kindersley, 1993.

Stuart, Chris and Tilde. Birds of Africa From Seabirds to Seed Eaters. Cambridge, MA: The MIT Press, 1999.

Periodicals:

McKechnie, Andrew E., and Barry G. Lovegrove. "Thermoregulation and the Energetic Significance of Clustering Behavior in the White-Backed Mousebird (Colius colius)." Physiological and Biochemical Zoology (March 2001): 238.