Coliiformes (Mousebirds)

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Coliiformes

Mousebirds

(Coliidae)

Class Aves

Order Coliiformes

Suborder Coliidae

Family Collidae

Number of families 1


Thumbnail description
Small, long-tailed birds with elongated crest-feathers on the head

Size
10.2–15.7 in (26–39.8 cm); 1–2.9 oz (28–82 g)

Number of genera, species
2 genera; 6 species

Habitat
Forest edge, woodland, and savanna

Conservation status
Not threatened

Distribution
Sub-Saharan Africa

Evolution and systematics

Mousebirds are not closely related to any other recent birds, but fossil remains of members of the closely related family Sandcoleidae have been discovered in Europe and northern America dating back to the Lower and Middle Eocene.

Physical characteristics

Soft, ragged plumage with fur-like gray and brown feathers give mousebirds a mouse-like appearance. They also have prominent crest feathers, long, stiff tails, short heavy bills, and heavy feet with first and fourth toes, called pamprodactylous, which can be turned forward and backward. The tail comprises about two-thirds of the bird's total body length. Between the lower jaw and the base of the skull is a supplementary joint that enables the birds to swallow large bits of food. Male and female mousebirds are alike.

Distribution

Mousebirds are now restricted to Africa south of the Sahara.

Habitat

Mousebirds inhabit forest edge, vegetation along rivers, woodland, and savanna with trees and brushwood.

Behavior

Mousebirds are very social birds most often seen in pairs or small family parties of five to seven, but occasionally in larger flights of 30 and more specimens, mostly during the dry seasons. Preening is very common behavior between pairs and members of a group. They cluster together during the day when they are resting and also during the night, holding on, much like bats, except with their heads up and their tails straight down. This clustering conserves body warmth and enables the birds to withstand low temperatures during the night. The body temperature may be lowered significantly as the birds fall into an energy-saving torpor, which is observed in only a few other bird groups such as hummingbirds. In torpor, the body temperature may be as low as 66.2–68°F (19–20°C).

Feeding ecology and diet

Almost exclusively vegetarians, mousebirds eat all sorts of fruit, buds, juicy leaves, and blossoms. They have been known to eat insects occasionally and captive specimens have used fresh pupae of ants to feed their young. They are rarely observed to eat meat, but are quite often seen to swallow earth, probably because of mineral contents.

Reproductive biology

Mousebirds frequently nest close together in loose colonies, although nests may also be widely dispersed. Individual pairs maintain a strong bond that can last for years. During courtship, males hop on the same spot on a twig, but occasionally also on the ground. Courtship may last for several minutes and does not always attract females. Courting males do not sing but utter low, throaty, clicking sounds to attract females. The simple, bowl-shaped nests are built in dense brush or in thorny bushes or trees usually not more than 6 ft (2 m) above the ground. Nesting materials such as small sticks, grass, fibers, roots, and moss are mostly brought by the males and arranged by the females. Even during incubation, green leaves may be added to the nests. In some areas, mousebirds have been known to build their nests near those of a dangerous wasp species, Belonogaster rufipennis. Thus, the mousebirds have protection from nest robbers, particularly tree snakes, and the wasps do not molest the birds. Eggs are relatively small (0.75–0.87 in [19–22 mm] long and 0.6–0.7 in [15–18 mm] wide) and have a strangely rough, coarse-grained white shell. Clutches usually consist of two to five eggs. Both sexes share in incubation of the eggs, which lasts only 11–12 days, and they relieve each other several times during those days. Newly hatched young weigh only 0.07 oz (2 g) or less, and their eyes are closed. They are almost naked or covered with only a sparse down coat, which grows quickly. Their eyes open and their first quills appear as early as the end of the first week. Towards the end of the second week, they are extensively feathered and, if threatened, they are able to leave the nest by climbing. Young mousebirds attempt their first flights when they are two and a half weeks old when they are still much smaller than their parents and have only a short tail. The young remain in close contact with their parents after leaving the nest and are still fed up to the age of four to six weeks. Birds from earlier broods may assist the parents in feeding the young and also assist in defending the nest and young.

Conservation status

Mousebirds are generally not threatened, but there are changes in distribution caused by human influence on vegetation.

Significance to humans

Some species, especially the bar-breasted mousebird (Colius striatus), have adapted to live near humans and may even be found in gardens and parks in villages and cities. However, as they sometimes cause damage to crops and fruit, they are often not well liked by humans. Mousebirds were first brought live to Europe in the 1870s, but were quite fragile initially. Mousebirds are not well suited to being kept in small cages, although life in aviaries in family groups agrees with them. While in natural surroundings they only reach an age of slightly more than 10 years, in captivity they may live for 12 years and more. Bar-breasted mousebirds were successfully bred in England as early as 1912, but have been regularly bred in more recent times. Young mousebirds removed from the nest and reared by hand can become very tame.

Species accounts

List of Species

Bar-breasted mousebird
Chestnut-backed mousebird
White-headed mousebird
White-backed mousebird
Blue-naped mousebird
Red-faced mousebird

Bar-breasted mousebird

Colius striatus

taxonomy

Colius striatus Gmelin, 1789, Cape of Good Hope, South Africa. Nineteen subspecies.

other common names

English: Speckled mousebird; French: Coliou strié, coliou rayé; German: Gestreifter Mausvogel, Braunflügel-Mausvogel; Spanish: Pájaro-ratón Común.

physical characteristics

10.2–14.2 in (26–36 cm); 1.3–2.8 oz (36–80 g). Feathers are mostly gray-brown, but the transverse bands are not distinct in all subspecies. The more southerly subspecies have bills with an entirely black upper mandible and a silver-gray lower mandible; in the northerly subspecies, there is a white spot on top of the upper mandible. Eastern African subspecies are also characterized by white feathers at the sides of the head, which give them the name, white-eared mousebirds. Color of iris varies from white to brown and greenish; the color may also differ above or below the pupil.

distribution

Nigeria to Eritrea, Somalia, across the Congo to northern Angola, and from eastern Africa to the western Cape.

habitat

Forest edge, riverine forest, open woodland, and dense brush, as well as cultivated land, secondary growth, gardens, and parks.

behavior

Live mostly in family groups, highly sedentary.

feeding ecology and diet

Fruits, buds, and leaves, and crops in cultivation and in human settlements.

reproductive biology

Breeding throughout the year if conditions are good, and in areas with dry seasons when food is available.

conservation status

Not threatened, even spreading in cultivated areas as observed in southern and eastern Africa.

significance to humans

Not liked by humans because they cause damage to orchards and gardens.


Chestnut-backed mousebird

Colius castanotus

taxonomy

Colius castanotus Verreaux & Verreaux, 1855, Gabon, error = Angola. Monotypic.

other common names

English: Red-backed mousebird; French: Coliou à dos marron; German: Rotrücken-Mausvogel; Spanish: Pájaro-ratón Dorsirrojo.

physical characteristics

11.4–15.0 in (29–38 cm); 1.4–2.9 oz (39–82 g). Upperparts are brown; underparts are grayish brown, buffy on belly. Has characteristic brown-red spot on the lower back rump. Face and forehead are black with whitish gray feather tips; sides of head and throat are grayish. Bill has black upper mandible with gray spot on culmen and whitish lower mandible. Feet are coral-red to scarlet. No barring on the feathers of the mantle, throat, or breast.

distribution

Western Angola from Congo mouth south to Namibia.

habitat

Forest edge, riverine growth, and cultivated land.

behavior

Live in pairs and family groups, sedentary.

feeding ecology and diet

Fruits, buds, leaves, and crops in cultivation and in human settlements.

reproductive biology

Breeding throughout the year when food supply is adequate.

conservation status

Not threatened, though uncommon in parts of distribution area.

significance to humans

Not liked by humans because they cause damage to orchards and gardens.


White-headed mousebird

Colius leucocephalus

taxonomy

Colius leucocephalus Reichenow, 1879, Kinakomba, lower Tana River, Kenya. Two subspecies.

other common names

French: Coliou à tête blanche; German: Weißkopf-Mausvogel; Spanish: Pájaro-ratón Cabeciblanco.

physical characteristics

11.4–13.0 in (29–33 cm); 1.0–1.5 oz (28–42 g). Grayish upperparts with black-and-white barring on upper back; buff under-parts with light barring on throat and breast. Creamy white crown, crest, and cheeks; blackish gray orbital skin. Bill has pale gray upper mandible with dark tip and paler lower mandible with yellowish tip. Feet are pinkish red to coral-red.

distribution

Southern Somalia through eastern Kenya to northern Tanzania.

habitat

Thorny woodland and savanna, but not far away from water supply.

behavior

Live in pairs or family groups, more or less sedentary.

feeding ecology and diet

Fruits, leaves, and blossoms, especially observed to feed on Salvadora berries.

reproductive biology

Mostly limited to breeding in seasons with best food supply, but will breed when enough food is available.

conservation status

Not threatened, but change in distribution possible following change in vegetation; no longer found in some areas where noted in the past.

significance to humans

They do not interfere with humans.


White-backed mousebird

Colius colius

taxonomy

Loxia colius Linnaeus, 1766, Cape of Good Hope, South Africa. Two subspecies.

other common names

French: Coliou à dos blanc; German: Weißrücken-Mausvogel; Spanish: Pájaro-ratón Dorsiblanco.

physical characteristics

11.4–13.0 in (29–33 cm); weight 1.3–2.3 oz (38–64 g). Has characteristic white back and dark red spot at the base of the tail; otherwise solid gray upperparts; buff underparts. Bill is bluish white with black tip. Legs and feet are coral-red.

distribution

Namibia, southern Botswana, and southern Africa eastwards to Central Transvaal and eastern Cape.

habitat

Woodland areas, riverine growth, and cultivated areas.

behavior

Live in family groups, sedentary.

feeding ecology and diet

Mostly fruits, some green matter, and nectar.

reproductive biology

Breed throughout the year when conditions are favorable.

conservation status

Not threatened, even spreading into cultivated areas.

significance to humans

Mostly none, but sometimes considered a pest.


Blue-naped mousebird

Urocolius macrourus

taxonomy

Lanius macrourus Linnaeus, 1766, Senegal. Seven subspecies.

other common names

French: Coliou huppé; German: Blaunacken-Mausvogel; Spanish: Pájaro-ratón Nuquiazul.

physical characteristics

12.6–15.7 in (32–39.8 cm); 1.2–2.2 oz (34–62 g). Ash-gray plumage; upperparts darker than underparts; turquoise-blue patch on nape and hindneck. Long crest and very long, slender tail. Female's tail is shorter than male's.

distribution

Western Africa from south Mauritania to Somalia and Tanzania.

habitat

Open woodland and savanna, often spreading in wetter seasons to breed, but moving to water-courses during the dry season.

behavior

Pairs separated for breeding are afterwards observed in family parties, and sometimes in large concentrations near rivers in the dry season.

feeding ecology and diet

Fruits and other green matter, especially dependent on Salvadora berries; more recently observed feeding in human cultivations.

reproductive biology

Fragile nests, eggs white with red-brown dots, streaks, and patches, clutches two to three eggs. Newly hatched young are naked with characteristic bulbous swellings at base of lower mandible. Grow quickly, flying after 16–18 days.

conservation status

Not threatened and obviously expanding into western Africa, following the introduction of cultivated plants.

significance to humans

Not yet regarded as pests.


Red-faced mousebird

Urocolius indicus

taxonomy

Colius indicus Latham, 1790, India, error = Gamtoos River, Cape Province, South Africa. Five subspecies.

other common names

French: Coliou quiriva; German: Rotzügel-Mausvogel, Brillen-Mausvogel; Spanish: Pájaro-ratón Carrirojo.

physical characteristics

11.4–14.3 in (29–37 cm); 1.6–2.3 oz (45.1–65.9 g); in captivity to 2.5 oz (72 g). Upperparts gray with metallic greenish sheen; underparts buff. Tail is very long and slender. Bare skin around eyes and on lores is carmine-red. Most of upper mandible is red and the rest of the bill is black. Feet are purplish red. subspecies differ primarily in intensity of plumage color.

distribution

Southern Africa from the Congo mouth, Angola, and southernmost Tanzania to the Cape.

habitat

Open woodland and savanna, moving widely for food supply; in recent times, more common in gardens and orchards in human settlements.

behavior

Live in pairs or family parties, sometimes observed in larger groups.

feeding ecology and diet

Fruits and other green matter.

reproductive biology

Eggs white with red-brown spots. Newly hatched young are naked with characteristic bulbous swellings at base of lower mandible. Grow quickly, flying after 16–18 days.

conservation status

Not threatened, but changing numbers noted in some areas following changes in vegetation.

significance to humans

Mostly none, but sometimes considered pests in gardens and other human cultivations.


Resources

Books

Schifter, H. Die Mausvögel (Coliidae). Wittenberg Lutherstadt: Die Neue Brehm Bücherei, A. Ziemsen Verlag, 1972. (Revised edition planned).

Periodicals

Brown, C. R., and G. G. Foster. "The Thermal and Energetic Significance of Clustering in the Speckled Mousebird, Colius striatus." Journal of Comparative Physiology B 162 (1992): 658–664.

Dean, W. R. J., J. B. Williams, and S. J. Milton. "Breeding of the White-backed Mousebird Colius colius in Relation to the Phenology of Fruiting Plants in the Southern Karoo, South Africa." J Afr Zool 107 (1993).

Decoux, J. P. "Les particularites demographiques et socioecologiques du Coliou strie dans le Nord-Est du Gabon." Rev Ecol (Terre et Vie) 36–37 (1982–1983): 37–78, 219–240.

Finke, C., A. Misovic, and R. Prinzinger. "Growth, the Development of Endothermy, and Torpidity in Blue-naped Mousebirds Urocolius macrourus." Ostrich 66 (1995): 1–9.

Prinzinger, R., R. Göppel, and A. Lorenz. "Der Torpor beim Rotrückenmausvogel Colius castanotus." J Orn 122 (1981).

Prinzinger, R., E. Schleucher, and A. Preßmar. "Langzeittelemetrie der Körpertemperatur mit synchroner Bestimmung de Energiestoffwechsels beim Blaunackenmausvogel (Urocolius macrourus) unter Normal- und Lethargiebedingungen." J Orn 133 (1992): 446–450.

Rowan, M.K. "A Study of the Colies of Southern Africa." Ostrich 38 (1967): 63–115.

Schifter, H. "Systematics and Distribution of Mousebirds (Coliidae)." Proc Intern Symp African Vertebr, Bonn (1985): 325–347.

Schifter, H. "Dispersal and Nomadism in Mousebirds (Coliidae)." Ostrich 65 (1994): 74–78.

Herbert K. Schifter, PhD