Broadbills: Eurylaimidae

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BROADBILLS: Eurylaimidae

AFRICAN BROADBILL (Smithornis capensis): SPECIES ACCOUNTS
BLACK-AND-RED BROADBILL (Cymbirhynchus macrorhynchos): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Broadbills are small- to medium-sized, stockily built birds with large eyes; a broad bill (from which they get the name) that is rounded along its sides, flattened from front to back, hooked at the end, and with a wide gap; rounded wings; a rather short, square tail (except for one species with a fine-pointed tail); short legs; strong, syndactylous (sin-DACK-tuh-lus; with fused digits) feet; and long, hooked claws. There is much difference among the species in the color of their plumage (feathers). Most birds are very colorful although some are rather dull looking, with colors ranging from browns with gray or black (in most African species) to green, red, blue, black, or silvery gray with many areas of bright colors (in most Asian species). Some species have an area of bare skin around the eyes that is sometimes pink or blue. Males and females look alike in some species but look different in others. Adults are 4.5 to 10.8 inches (11.5 to 27.5 centimeters) long and weigh between 0.4 and 6 ounces (10 and 171 grams).


GEOGRAPHIC RANGE

Broadbills are found in sub-Saharan Africa, Himalayan portions of India, Thailand, Cambodia, Vietnam, far southern China (also Hainan Island), Borneo, Sumatra, Java, peninsular Malaysia, and the Philippines.


HABITAT

Broadbills inhabit mostly humid tropical and subtropical lowlands (including evergreen or mostly evergreen broad-leaved lowland forests), while a few species are located in montane (mountain) forests and one species is found in dry climates. They move with the change of seasons to mountain areas when food becomes scarce.


DIET

Most broadbills eat insects, but some of the larger species also eat small vertebrates (animals with a backbone) such as lizards, frogs, small crabs, and small fish, and fruits such as figs. Foods are foraged from leaves or branches, caught while in flight, or captured on the ground.


BEHAVIOR AND REPRODUCTION

The behavior and reproduction habits of broadbills are not known very well. The birds are generally arboreal (live in trees) and are believed to be mostly monogamous (muh-NAH-guh-mus; having one mate), but some species may be polygamous (puh-LIH-guh-mus; having more than one mate). Broadbills join single or mixed species flocks, but avian experts do not know whether the birds remain in one territory, range over several territories, or return to a territory after leaving. When defending a territory or during courtship, broadbills perform various displays of songs and flights. Simple songs usually consist of dove-like cooing, croaks, trills, whistles, and a series of bubbly to screaming notes.

Broadbills have a mating and reproduction period that is tied to rainfall amounts. Some species reproduce during the dry season, while others mate during the rainy season. All of the birds make large domed nests in the shape of a pear that is suspended from the tips of branches. In almost all species, both males and females build nests. Such nests are made from twigs, rootlets, and leaf strips from plants such as grasses, bamboo, and palms. Oftentimes, spider webs, moss, cocoons, and other materials hide the nests. At other times, nests are hung above water to make it difficult for predators, animals that hunt them for food, to enter. Females lay two to six white to pinkish eggs that are sometimes unmarked or speckled reddish or purple. Males help females with the care of the young, and some species also use helpers, related, nonbreeding birds that help care for the young.


BROADBILLS AND PEOPLE

People hunt broadbills for their colorful plumage in order to sell them within the pet industry.

CONSERVATION STATUS

Three broadbill species are listed on the IUCN Red List as Vulnerable, facing a high risk of extinction, due to deforestation, mining, and human warfare in their very small ranges. Three other species are listed as Near Threatened, in danger of becoming threatened with extinction.

AFRICAN BROADBILL (Smithornis capensis): SPECIES ACCOUNTS

Physical characteristics: African broadbills are stocky, short-tailed birds with a distinctive broad, flat bill. They have a brownish head and upperparts, and buffy underparts that are streaked with blackish colors. Males have a black crown (top of head), gray lower nape (back of neck), black upper mandible (top part of the bill) and whitish lower mandible (bottom part), and reddish brown upperparts and tail. The mantle (back, inner-wing, and shoulder area) has broad black streaks. White under-parts are deeply streaked with black except on the central belly and rump, and the legs are olive to yellowish green. Females look like males but are duller overall, with a gray crown that has black streaks. Juve-niles look like females but with less buff on forehead and a brown crown with faint streaks. Adults are 4.7 to 5.5 inches (12 to 14 centimeters) long and weigh between 0.7 and 1.1 ounces (20 and 31 grams).

Geographic range: African broadbills are found in various scattered spots in central and southern Africa including Cameroon, Gabon, Central Africa Republic, Sierra Leone, Liberia, Ivory Coast, Ghana, Malawi, Democratic Republic of the Congo, Tanzania, Kenya, Zambia, Mozambique, Rwanda, Uganda, Angola, Namibia, and South Africa.


Habitat: African broadbills inhabit the understory (lower vegetation of a forest) of primary and secondary forests, dense deciduous thickets, montane forests, riparian forests (along or near banks of rivers), a variety of woodlands and savannas (flat grasslands), and open agricultural lands. They are usually found at elevations below 2,300 feet (700 meters), but can be found as high as 8,000 (2,440 meters).


Diet: Their diet consists of insects such as caterpillars, butterfly eggs, and ants. They often rush forward to snag prey, sometimes even falling to the ground in order to capture food.


Behavior and reproduction: African broadbills are territorial birds. Both males and females perform elliptical display flights. During courtship, both birds face each other on a horizontal branch and flick their wings, changing between perching and hanging positions. Their call is a "twee-uu," probably to keep in contact with other birds and to show alarm or distress. A whistled "huiii" and a mewing-like call are used during courtship. They build a bag-like nest of plant fibers, dead leaves, moss, and twigs with a rough-looking hanging tail. An entrance is made high on the side. The inside of the nest is lined with soft bark, dry stems, leaves, and grasses, and kept together with spider silk. Their breeding season varies depending on where they are located. Females lay one to three eggs.


African broadbills and people: There is no known significance to humans.


Conservation status: African broadbills are not threatened. They are common in many areas, but scarce in others, mostly due to habitat destruction. ∎

BLACK-AND-RED BROADBILL (Cymbirhynchus macrorhynchos): SPECIES ACCOUNTS

Physical characteristics: Black-and-red broadbills are beautiful crimson and black birds. They have a black head, back, and tail feathers; crimson red underparts, rump, and throat; black wings with a white narrow stripe; and a bill that is pale blue on top and yellow below. Adults are 8.3 to 9.4 inches (21 to 24 centimeters) long and weigh between 1.8 and 2.7 ounces (50.0 and 76.5 grams).


Geographic range: They are found in Borneo, Myanmar, southern Thailand, southern Laos, south Vietnam, peninsular Malaysia, and Sumatra.


Habitat: Black-and-red broadbills occupy areas with water within evergreen forests.

Diet: Their food consists of mostly insects, but also mollusks, crabs, and small fish.


Behavior and reproduction: The behavior and reproduction habits of black-and-red broadbills are not well known. They are usually found in pairs or small groups. Nests are often built in dead stumps or along bends in streams. The breeding season usually occurs in the dry season. Females lay two to three eggs. Males may help females incubate (sit on) the eggs.


Black-and-red broadbills and people: There is no known significance between people and black-and-red broadbills.

Conservation status: Black-and-red broadbills are not threatened. They are fairly common throughout their range, but their habitat is being reduced, mostly due to human activities. ∎


FOR MORE INFORMATION

Books:

del Hoyo, Josep, Andrew Elliott, Jordi Sargatal, Jose Cabot, 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.

Perrins, Christopher M., and Alex L. A. Middleton, eds. The Encyclopedia of Birds. New York: Facts on File, 1985.