Broadbills

(Eurylaimidae)

Class Aves

Order Passeriformes

Suborder Tyranni (Suboscines)

Family Eurylaimidae

Thumbnail description
Small to medium-sized birds, some very colorful, most with a broad head, broad bill wide gape, and large eyes

Size
4.5–10.8 in (11.5–27.5 cm); 0.35–6.0 oz (10–171 g)

Number of genera, species
8 genera; 15 species

Habitat
Mostly humid tropical lowland or montane forest

Conservation status
Vulnerable: 3 species; Near Threatened: 3 species

Distribution
Sub-Saharan Africa and Southeast Asia including Hainan Island, Borneo, Sumatra, and Java

Evolution and systematics

The broadbills are a small family with only 15 species and eight genera. Their taxonomic position was somewhat of a mystery for most of the twentieth century, but recent phylogenetic studies using morphological and molecular (DNA sequencing) data have shown that the broadbills form a monophyletic group with the pittas (Pittidae) and asities (Philepittidae). Together, these three families comprise the Old World suboscines, a group that shares a tracheobronchial syrinx, or vocal apparatus. Richard Prum suggests that the asities are the sister group of the African green broadbill (Pseudocalyptomena graueri). His Eurylaimidae thus consists of five subfamilies: Smithornithinae, Calyptomenanae, Eurylaiminae, Pseudocalyptomenanae, and the Philepittinae.

The eight genera in this family are quite distinct and do not appear to be closely related. They may be the last survivors of a once much more diverse group that was slowly replaced by a radiation of oscine songbirds. The origin of the broadbills is still a matter of speculation. Suboscines probably evolved on Gondwana, so it seems reasonable to hypothesize an African origin (giving rise to the ancestors of Smithornis) following the break up with South America. Broadbills then diversified by spreading into Asia (Calyptomena, Eurylaimus, Corydon, Serilophus) and then back to Africa (Pseudocalyptomena and asities).

Physical characteristics

Broadbills are small to medium-sized birds ranging from 4.5 to 10.8 in (11.5–27.5 cm) in length and weighing 0.35–6.0 oz (10–171 g). Broadbills share a host of characters in their syrinx and hindlimb musculature. Except for Calyptomena they are unique among the passerines in having 11 primaries. Most species have an exceptionally wide bill and gape. The dusky broadbill (Corydon sumatranus) beats all records among the passerines with a pink, hooked bill that is as wide as it is long. It even surpasses the skull in width. The more frugivorous Calyptomena and Pseudocalyptomena have a much narrower bill, but have retained a wide gape.

In terms of plumage coloration, the broadbills are a diverse group. Apart from a few dull-colored species, most broadbills are quite colorful, spanning the range from blue to red. Some species also have an area of bare skin around the eyes that is blue in the two Philippine Eurylaimus and pink in the dusky broadbill. Whereas the two sexes look alike in some species, more or less subtle difference can be found in others. Sexual dimorphism is most obvious in Calyptomena. Here the males are more intensely colored and the loral feathers form a forward facing tuft that covers the base of the bill, resembling a small crest.

Distribution

The highly fragmented distribution of broadbills is limited to tropical and subtropical sub-Saharan Africa, Himalayan India, Thailand, Cambodia, Vietnam, extreme southern China (also Hainan Island), Borneo, Sumatra, Java, peninsular Malaysia, and the Philippines. Smithornis and Pseudocalyptomena are the only genera occur in Africa. Hose's broadbill (Calyptomena hosii) and Whitehead's broadbill (C. whiteheadi) are restricted to Borneo and the Mindanao and Visayan wattled broadbill (Eurylaimus steerii and E. samarensis) are restricted to a few islands in the Philippine archipelago.

Habitat

Broadbills are inhabitants of humid forests. Only the African broadbill uses somewhat drier areas. Interestingly, most broad-bills inhabit mountainous terrain. Those species that primarily occur in the tropical lowlands move seasonally into montane forests as a response to changing resource levels. Many species are tolerant of some human caused disturbance, but most require primary forest for long-term persistence.

Behavior

Little is known about broadbill mating systems and general behavior. Most species appear to be monogamous. However, the frugivores (Calyptomena, Pseudocalyptomena) may be polygynous as they appear to form leks. Territoriality is another area that requires more research. Most broadbills join single or mixed species flocks, but it is still unclear if they remain in, or always return to, the same territory. There is evidence, however, that Calyptomena ranges over wide areas in search of fruit.

Broadbills perform a variety of displays that may be related to territory maintenance or courtship. The best-described species are the Smithornis broadbills, which make characteristic elliptical flights, and the green broadbill, which has a series of complex displays. The songs are rather uncomplicated, consisting of whistles, trills, dove-like cooing, and variable series of notes described with different qualities, from bubbly to screaming.

Feeding ecology and diet

Most broadbills are insectivorous. Some species also eat small vertebrates, such as lizards and small fish. The three Calyptomena species are frugivorous, depending to a large degree on figs. Fruit also makes up a large component of the African green broadbill's diet. Most of the food is either gleaned from leaves or branches, or caught in flight. Some broadbills (Smithornis, Cymbirhynchus) also drop to the ground to catch prey.

Reproductive biology

The reproductive season depends mostly on the local rainfall regimes. Some species tend to nest during the dry season and others during the rainy season. All broadbills make pendant nests. Common nest materials include fibers, strips of leaves from monocotyledonous plants, such as grasses, bamboo, and palms, and other leaves. Smithornis also interweave black fungal strands. Spider webs and cocoons,

moss, and other materials camouflage the nests. Except in Smithornis and Calyptomena, nests are suspended from the tips of branches, and are hard for predators to reach. Locating the nests above water further deters predators. Cymbirhynchus suspends its nests 5–26 ft (1.5–8 m) above rivers or other water bodies. While protected from predators, nests in the lower range are often destroyed by rising water levels.

Two to six eggs are laid. With the possible exception of Calyptomena, both sexes build the nest. Male parental care appears to be common in most species. The dusky and long-tailed broadbills may even be cooperative breeders as more than two individuals of the species have been observed around nests. As an interesting side note, female green broadbills' heads protrude from the nest entrance. Why? Nobody knows. Much needs to be learned about broadbill reproductive behavior.

Conservation status

Six out of 15 species are on the IUCN Red List. Three species are considered Vulnerable and three Near Threatened. With no more than 10,000 individuals each, the vulnerable species all have tiny ranges that are threatened by deforestation, mining activities, and/or guerilla warfare (on Mindanao, Philippines). Deforestation of lowland forest threatens Hose's, White-head's and black-and-yellow (Eurylaimus ochromalus) broadbills.

Significance to humans

Most broadbills are colorful birds. However, little information is available on their significance in the pet trade. The silver-breasted broadbill (Serilophus lunatusis) is sold at local markets in Thailand. The African broadbill has the distinction of being the first suboscine whose entire mitochondrial genome has been sequenced.

Species accounts

List of Species

African broadbill

Smithornis capensis

subfamily

Eurylaiminae (Smithornithinae)

taxonomy

Platyrhynchus capensis A. Smith, 1840, Natal (coastal forests of northern Zululand). Nine subspecies are recognized.

other common names

French: Eurylaime du cap; German: Kapbreitrachen; Spanish: Pico Ancho Africano.

physical characteristics

4.7–5.5 in (12–14 cm); 0.7–1.1 oz (20–31 g). Brownish head and upperparts. Underparts buffy streaked with blackish.

distribution

S. c. capensis: South Africa in coastal Natal and southern Zululand. S. c. camerunensis: Cameroon, Gabon, Central Africa. S. c. delacouri: Sierra Leone, Liberia, Ivory Coast, and Ghana. S. c. albigularis: Central Africa, in northern Malawi, northern Zambia, Democratic Republic of Congo, Tanzania, and isolated in Angola. S. c. meinertzhageni: highlands of northeastern Democatic Republic of Congo and adjacent Rwanda and Uganda, western Kenya. S. c. medianus: highlands of central Kenya and northeastern Tanzania. S. c. suahelicus: from southeastern Kenya south to Mozambique, as far inland in Tanzania as the Uluguru and Nguru Mountains. S. c. conjunctus: from southern Angola through northeastern Namibia to northwestern Mozambique. S. c. cryptoleucus: from southwestern Tanzania

and southern Malawi south to South Africa (Zululand). Although more common below 2,300 ft (c. 700 m) elevation, it can be found as high as 8,000 ft (2,440 m) in the Usumbara Mountains, Tanzania.

habitat

Variable; generally inhabits the understory of primary and secondary forests, riparian forests, a variety of woodlands, dense thickets and brush, disturbed areas, montane forests, and open agricultural lands.

behavior

Territorial. Both sexes commonly perform elliptical display flights. During courtship both birds face each other on a horizontal branch and flick their wings, changing between a perching and a hanging position.

feeding ecology and diet

Insectivorous. Forage by sallying and occasionally tumbling to the ground.

reproductive biology

Breeding season very variable depending on locality. Lays two to three eggs.

conservation status

Not threatened. Locally common, but scarce in some areas. This species has suffered from habitat destruction in some places.

significance to humans

None known.

Hose's broadbill

Calyptomena hosii

subfamily

Calyptomeninae

taxonomy

Calyptomena hosii Sharpe, 1892, Mt. Dulit, Borneo.

other common names

English: Blue-bellied broadbill, magnificent green broadbill; French: Eurylaime de Hose; German: Azurbreitrachen; Spanish: Pico Ancho Magnífico.

physical characteristics

7.5–8.3 in (19–21 cm); female, 3.3 oz (92 g); male, 3.6–4.1 oz (102–115 g). Green head and upperparts with black spots about head and neck, and on wings. Deep blue underparts.

distribution

Endemic to Borneo. Most commonly found between 2,000 and 4,000 ft (610–1,220 m), but also as low as 1,000 ft (300 m) in Sabah and as high as 5,512 ft (1,680 m) in the Kelabit Uplands.

habitat

Understory and midstory of submontane forest; locally in lowland rainforest.

behavior

Little known. Occurs in pairs or small groups.

feeding ecology and diet

Feeds mostly on fig fruits, but also some insects and leaf buds. Small groups can be seen aggregating in fruiting fig trees.

reproductive biology

Breeding probably begins in March to April.

conservation status

Rare to locally common in very restricted distribution. Considered Near Threatened.

significance to humans

None known.

Black-and-red broadbill

Cymbirhynchus macrorhynchos

subfamily

Eurylaiminae

taxonomy

Todus macrorhynchus Gmelin, 1788, no locality. Four subspecies recognized.

other common names

French: Eurylaime rouge et noir; German: Kellenschnabel; Spanish: Pico Ancho Negro y Rojo.

physical characteristics

8.3–9.4 in (21–24 cm); 1.8–2.7 oz (50–76.5 g). Black head, back, and tail feathers. Red underparts and on rump and throat. Black wings with white stripe. Bill is light blue above and yellow underneath.

distribution

C. m. macrorhynchus: Borneo. C. m. affinis: western Myanmar. C. m. malaccensis: Myanmar, southern Thailand, southern Laos,

south Vietnam, and peninsular Malaysia. C. m. lemniscatus: Sumatra.

habitat

Evergreen forest always near water, also in degraded areas.

behavior

Not well known. Usually found in pairs or small groups. Male may incubate eggs.

feeding ecology and diet

Mostly insectivorous. Occasionally takes mollusks, crabs, and small fish.

reproductive biology

Reproduces mostly in dry season. Lays two to three eggs.

conservation status

Not threatened; fairly common, but range contracting.

significance to humans

None known.

Long-tailed broadbill

Psarisomus dalhousiae

subfamily

Eurylaiminae

taxonomy

Eurylaimus dalhousiae Jameson, 1835, northern India. Four sub-species recognized.

other common names

French: Eurylaime psittacin; German: Papageibreitrachen; Spanish: Pico Ancho de Cola Larga.

physical characteristics

9.1–10.2 in (23–26 cm); 1.9–2.4 oz (53–67 g). Yellow face, black head with blue and yellow spots. Light green underparts,

darker green upperparts and wings. Primaries black and blue. Long blue tail.

distribution

P. d. dalhousiae: Himalayas to northeast India and southeastern Bangladesh, south to northern Thailand, Laos, and north Vietnam. P. d. psittacinus: peninsular Malaysia and Sumatra. P. d. borneensis: northwestern Borneo. P. d. cyanicauda: southern Indochine peninsula.

habitat

Tropical and subtropical evergreen or semi-evergreen forest up to 6,560 ft (2,000 m) elevation in Himalayas.

behavior

Travel in flocks during nonbreeding season, but pairs tend to be secretive during the breeding season. Often sits motionless in lower canopy.

feeding ecology and diet

Insectivorous, taking prey by gleaning or sallying.

reproductive biology

Start of breeding season depends on locality, but generally between March and June. Lays five to six eggs.

conservation status

Not threatened; common throughout its range.

significance to humans

None known.

Silver-breasted broadbill

Serilophus lunatus

subfamily

Eurylaiminae

taxonomy

Eurylaimus lunatus Gould, 1833 (1834), near Rangoon. Eight subspecies recognized.

other common names

English: Gould's broadbill, collared broadbill, Hodgson's broadbill; French: Eurylaime du Gould; German: Würgerbreitrachen; Spanish: Pico Ancho de Pecho Plateado.

physical characteristics

6.3–6.7 in (16–17 cm); 0.9–1.2 oz (25–35 g). Grayish head with black behind eyes. Whitish breast and wingtips. Wings alternate black and blue with some rusty color. Back is light gray, turning to dark rust colored at rump and black on the tail.

distribution

S. l. lunatus: Myanmar and northwestern Thailand. S. l. rubropygius: Nepal east to northeastern India, Myanmar. S. l. elisabethae: northeastern Myanmar, eastern Thailand, southern China, Vietnam, and north central Laos. S. l. impavidus: Bolovens Plateau, southern Laos. S. l. rothschildi: penisular Malaysia and southern peninsular Thailand. S. l. intesus: Sumatra. S. l. polionotus: mountains of Hainan. S. l. stolidus: southern Myanmar and northern peninsular Thailand. Elevational range variable, depending on location from lowlands to 7,320 ft (2,230 m) in Thailand.

habitat

Evergreen and semi-evergreen tropical and subtropical forests. Often associated with bamboo.

behavior

In pairs or mixed and single species flocks. Both parents, and possibly helpers, care for brood. Some altitudinal and short distance movements.

feeding ecology and diet

Mostly insectivorous; also eats snails and small lizards. Feeds by gleaning from foliage and branches, ocassionally sallying.

reproductive biology

Breeding begins in March to July depending on locality. In the north coincides with abundant rain and in the south with dry conditions. Lays four to seven eggs.

conservation status

Not threatened; rare to locally common. Sold in the local pet trade in Thailand.

significance to humans

Used as cage bird.

Black-and-yellow broadbill

Eurylaimus ochromalus

subfamily

Eyrylaiminae

taxonomy

Eurylaimus ochromalus Raffles, 1822, Singapore Island. Three subspecies recognized.

other common names

French: Eurylaime à capuchon; German: Halsband-Breitra-chen; Spanish: Pico Ancho Negro y Amarillo.

physical characteristics

5.3–5.9 in (13.5–15 cm); 1.1–1.4 oz (31–39 g). Blue bill, black head, white band at throat. Whitish to rosy breast to yellow behind abdomen. Wings and tail black with yellow bands on wings, white spots on tail.

distribution

E. o. ochromalus: peninsular Thailand and Malaysia, Sumatra, Borneo, Riau and Lingga Archipelagoes, Belitung, Bangka, Batu, and North Natuna Islands. E. o. mecistus: Tuangku Island to the northwest of Sumatra. E. o. kalamantan: Sarawak.

habitat

Evergreen forests, lower montane rainforests, peat swamp and tidal swamp forests, and mixed dipterocarp forests. Also in

logged forests, secondary vegetation, and overgrown plantations.

behavior

During courtship display the male stretches its wings and wags its tail, whereas the female shivers her half-spread wings, exposing a white rump.

feeding ecology and diet

Insectivorous, eats little fruit. Catches insects by sallying.

reproductive biology

Breeding between February and October depending on locality. Lays two to three eggs.

conservation status

Not threatened.

significance to humans

None known.

Visayan wattled broadbill

Eurylaimus samarensis

subfamily

Eurylaiminae

taxonomy

Sarcophanops samarensis Steere, 1890, Catbalogan, Samar.

other common names

English: Samar broadbill, Visayan broadbill; French: Eurylaime de Steere; German: Philippinenbreitrachen; Spanish: Pico Ancho Caranculado.

physical characteristics

5.7–5.9 in (14.5–15.0 cm); 1.2–1.5 oz (33.5–41.5 g). Dark reddish head, upperparts, and tail. Black on wings and under bill. White band around throat and on wings. Upper breast is rosy, turning to white below.

distribution

Leyte, Samar, and Bohol in the Visayan Islands, Philippines.

habitat

Understory of primary forest between 330 and 1,975 ft (100–600 m).

behavior

Little known. Usually found in pairs, small groups, or mixed-species flocks.

feeding ecology and diet

Insectivorous, may eat some fruit.

reproductive biology

Probably breeds February to June.

conservation status

Vulnerable. Threatened by deforestation. This species has a very small occupied range and a small population.

significance to humans

None known.

Dusky broadbill

Corydon sumatranus

subfamily

Eurylaiminae

taxonomy

Coracius sumatranus Raffles, 1822, interior of Sumatra. Three subspecies recognized.

other common names

French: Eurylaime corydon; German: Reisenbreitrachen; Spanish: Pico Ancho Sombrío.

physical characteristics

9.4–10.8 in (24–27.5 cm); about 4.9 oz (140 g); has exceptionally broad bill and wide gape. Black body, white at throat and white banding on tail.

distribution

C. s. sumatranus: Sumatra, peninsular Malaysia and Thailand, and Penang Island. C. s. laoensis: Patchily in Myanmar, northern Thailand, Laos, Cambodia, and Vietnam. C. s. brunnescens: Borneo and North Natuna Islands. Possibly up to 6,600 ft (2,000 m).

habitat

Canopy of rainforests and primary and logged evergreen and deciduous forests.

behavior

Probably a cooperative breeder. Usually found in groups.

feeding ecology and diet

Feeds on large insects (up to 3.1–3.9 in [8–10 cm] in length) and lizards. Usually gleans after a short flight.

reproductive biology

In northern part of the range breeding starts at the end of the dry season, in the southern part during the rainy season. Lays four to six eggs.

conservation status

Not threatened, though habitat loss due to logging and deforestation may have led to a range contraction.

significance to humans

None known.

African green broadbill

Pseudocalyptomena graueri

subfamily

Eurylaiminae (Pseudocalyptomeninae)

taxonomy

Pseudocalyptomena graueri Rothschild, 1909.

other common names

English: Grauer's broadbill; French: Eurylaime de Grauer; German: Blaukehl-Breitrachen; Spanish: Pico Ancho Verde Africano.

physical characteristics

5.35–6.14 in (13.6–15.6 cm); 1.0–1.2 oz (29.0–32.5 g). Grayish head, whitish below bill onto breast. Upper-and underparts green. Dark tail.

distribution

Known only from a few localities in extreme eastern Democratic Republic of Congo and western Uganda.

habitat

Primary montane forest with dense bamboo, forest edge, and cultivated areas between 5,770 and 8,140 ft (1,760–2,480 m).

behavior

Little known; it can be found singly, in small groups, or mixed-species flocks. May perform display flights.

feeding ecology and diet

Omnivorous, including fruit, seeds, flowers, insects, and small snails in its diet. Probably feeds by flycatching.

reproductive biology

Breeding reported between April and July.

conservation status

Vulnerable. Threatened in its tiny range by deforestation, commercial logging, and mining.

significance to humans

None known.

Resources

Books

BirdLife International. Threatened Birds of Asia: The BirdLife International Red Data Book. Cambridge, UK: BirdLife International, 2001.

Lambert, Frank, and Martin Woodcock. Pittas, Broadbills and Asities. Sussex, UK: Pica Press, 1996.

Periodicals

Irstedt, Martin, Ulf S. Johansson, Thomas J. Parsons, and Per G. P. Ericson. "Phylogeny of Major Lineages of Suboscines (Passeriformes) Analysed by Nuclear DNA Sequence Data." Journal of Avian Biology 32 (2001): 15–25.

Prum, Richard O. "Phylogeny, Biogeography, and Evolution of the Broadbills (Eurylaimidae) and Asities (Philepittidae) Based on Morphology." Auk 110 (1993): 304–324.

Organizations

BirdLife International Indonesia Programme. P. O. Box 310/Boo, Bogor, Indonesia. Phone: +62 251 357222. Fax: +62 251 357961. E-mail: [email protected] Web site: <http://www.birdlife-indonesia.org>

Other

World Conservation Monitoring Center. "Threatened Animals of the World. UNEP-WCMC Animal Database." <http://www.unep-wcmc.org/>

Markus Patricio Tellkamp, MS