Bulbuls (Pycnonotidae)

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Bulbuls

(Pycnonotidae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Pycnonotidae


Thumbnail description
Medium sized, short-necked songbirds with short round, wings; fluffy plumage, many with crested heads

Size
3.6–11.5 in (9.3–29 cm); 0.5–2 oz (15–59 g)

Number of genera, species
15 genera; 123 species

Habitat
Forest, forest edge, open woodland, scrub, cultivated lands

Conservation status
Endangered: 2 species; Vulnerable: 5 species

Distribution
Africa, Indian subcontinent, Asia, Indonesia, northwestern Australia, Malagasy region, introduced populations in United States

Evolution and systematics

In the introduction to his 1945 revision of the family Pycnonotidae, Jean Delacour states that "The bulbuls constitute one of the most clearly defined groups of perching birds (Passeres). This means that the different genera and subgenera which belongs to the group are obviously related to one another, and rather far removed from any others." Recognition of the bulbuls as a "natural" group has not stood the test of time, however, and the placement of the Pycnonotidae within Passeriformes remains unresolved, as do the relationships of these songbirds to each other.

Depending on the characters examined, the Pycnonotidae have been allied with a number of families. Early authors placed them next to cuckoo-shrikes (Campephagidae) based on shared anatomical and plumage characters, such as abundant rump feathers. Egg-white protein analysis in the early 1970s suggested a relationship to drongos (Dicruridae) or starlings and orioles (Sturnidae, Oriolidae). Current DNA evidence suggests that bulbuls belong in the superfamily Sylvioidea, between kinglets (genus Regulus, sometimes treated as a family, Regulidae) and the African warblers (genus Cisticola, sometimes treated as a family, Cisticolidae). More controversial than the family placement however, are the relationships of various bulbuls to each other. Several species will probably eventually be shuffled to different genera and even other families as research continues. DNA analyses in 2001 suggest that the African and Asiatic genus Criniger, united chiefly by the conspicuously colored throat, is not a natural group. This study recommends that the Asian Criniger take the genus name Alophoixus, and the African species remain as Criniger. Other research examining the relationships of 13 birds endemic to Madagascar, including some of the African greenbuls (Phyllastrephus spp.) found that the Malagasy genera, normally distributed across three families, were actually all most closely related to each other. Some ancient relative of these birds probably arrived at the island at least nine million years ago, then evolved and diversified there rather than different birds of different lineages colonizing the island several times, as previously thought. This study recommends that the Malagasy bulbuls be removed from the genus.

Also controversial is the placement of two of the endemic African genera Neolestes and Nicator. The striking plumage of the black-collared bulbul (Neolestes torquatus) allies it with the shrikes (Malaconotidae, Laniidae, or Prionopidae), DNA data ally it with other bulbuls. Similarly, Nicator has also been allied with the shrikes, but feather protein and DNA evidence suggest the birds are bulbuls. Because the three Nicator species and Neolestes lack a thin sheet of nostril-covering bone that is present in the rest of the bulbuls, they are sometimes placed elsewhere.

Whatever their relationships, it is clear that birds considered bulbuls evolved in the last 10 million years and much of the family may have radiated more recently, probably during the Plio-Pleistocene, about 2.8 million years ago. During the Tertiary, northern Africa experienced general drying, and the eastern lowland forests became isolated as mountains swelled and rifted in the region. Andropadus probably colonized these "new" mountain habitats, which became centers of speciation for the group.

Physical characteristics

Most of the bulbuls are dressed in somber browns, olive tones, or grays, and are often heard before they are seen. However, several species have distinctive face markings with a bright splash of red, yellow, orange, or white plumage. The plumage of Pycnonotus tends to be more variable than other genera, and these birds usually have are a red, yellow, orange, or white "vent" which contrasts with the rest of their underparts. Many species, especially among the Pycnonotus, Criniger, and some Hypsipetes, have long crown feathers that form a prominent head crest; the crest is absent in Andropadus. Almost all have at least a few bristles on the nape of their short necks and a small area without feathers, such that a bulbul with its neck stretched out shows a small bare patch between the nape and upper back. The tail can be fairly long, usually with a round tip, although it is slightly forked in some species.

Small to medium-sized birds, bulbuls range in size from 3.6 to 11.5 in (9.3–29 cm); and between 0.5 and 2 oz (15–59g). Except for the finchbills (Spizixos spp.), the pycnonotids have medium-sized, slender, notched bills. Among the Criniger, the bill is usually strongly hooked at the tip. Bulbuls tend to have short, weak legs and short, rounded wings. Males and females usually look alike, though the female is often slightly smaller; this size difference is greatest in Phyllastrephus. Likewise, the juveniles look like the adults, but their plumage is duller and often more brown.

Distribution

Bulbuls occur mainly in forest and wooded areas across Africa and Madagascar, north to the Middle East and Japan, and east to the Philippines and Indonesia. Except for recently introduced species, there are no bulbuls in the New World. Of the roughly 120 species, there are 27 species in China. About 52 species (in 11 genera) are African, and bulbuls are widely distributed across that continent, being absent only from desert regions. Nine genera are found exclusively in Africa, and two of the larger genera (Pycnonotus and Criniger) are found in both Africa and Asia. The most ubiquitous of the Pycnonotus species is the common bulbul (P. barbatus). This bold and noisy bird is well adapted to man-made habitats and is one of the most widespread and abundant birds in Africa.

Many bulbuls are endemics and have quite restricted distributions, especially those on oceanic islands. The yellow-eared bulbul (Pycnonotus pencillatus) is found exclusively in the montane areas of Sri Lanka; the Nicobar bulbul (Hypsipetes nicobariensis) occurs only on the southern Nicobar Islands south of Burma. Others are widespread and common, the yellow-vented bulbul (Pycnonotus goaivier), occurring from southern Vietnam to the Malay Peninsula and the Philippines, is probably the most commonly seen bulbul of the region. An opportunistic bird, it is often seen around gardens, feeding on food scraps and using potted plants to nest in.

In 1960 a population of red-whiskered bulbuls (Pycnonotus jocosus) became established in Florida when a few birds escaped while being transported from one aviary to another. This population had increased to 500 birds by 1973, at which time it was still expanding in a southerly direction. Redwhiskered bulbuls also became established in Los Angeles County, California, in 1968. Both the red-whiskered and red-vented

bulbuls (P. cafer), were introduced to the Hawaiian island of O'ahu in the late 1960s. Populations of both birds have dramatically increased. Red-vented bulbuls are now found across the island, while the red-whiskered bulbul is found throughout southeastern areas. These birds are considered serious pests and threats to native bird populations.

Habitat

Forest, open woodland, gardens, and cultivated areas all constitute bulbul habitat. Essentially arboreal birds, the majority of pycnonotids live in or next to forested areas, but many are well adapted to human-made habitats. Many bulbuls show a preference for a particular level of the forest canopy. So as long as there is enough fruit and insects, a relatively small area of forest may support a large number of birds.

The majority of Andropadus species keep to the forest interior, as do many others, such as Finsch's bulbul (Criniger finschii) of Indonesia, and the African gray-headed greenbul (Phyllastrephus poliocephalus). Other species prefer more open areas and are found frequently in edge habitat. The gray-headed bristlebill (Bleda canicapilla) and the white-throated greenbul (Phyllastrephus albigularis), both found exclusively in western north-central Africa, are typically found at forest clearings and edges where there is tangled vegetation in which they can forage for insects. Pycnonotus species are well adapted to drier habitats, and are frequently found in areas that have been cultivated by humans. A few are confined to the forest, but they generally inhabit open country with scattered trees and shrubs. The yellow-throated leaf-love (Chlorocichla flavicollis) actually avoids large forest blocks, occurring mainly in brushy, more open areas. This bird also adapts extremely well to man-made habitats; and can be found in plantations, abandoned cultivated sites, orchards, parks, and gardens.

Several bulbuls show a preference for water and are found alongside rivers and forest streams. The gray-olive bulbul (Phyllastrephus cerviniventris) is one such bird. Infrequently entering the forest, this smallish bulbul frequently inhabits streamside thickets. Primarily an insect eater in Zambia, it is especially fond of feeding on logs that have fallen across streams or ravines. The swamp greenbul (Thescelocichla leucopleura) and the leaf-love (Pyrrhurus scandens) are also partial to water, both prefer swampy areas with luxuriant vegetation and palm trees, especially Raphia and the oil palm Elaeis.

Although most bulbuls prefer areas with lots of green vegetation, a small number are found in drier scrub habitats, especially Pycnonotus. The African red-eyed bulbul (Pycnonotus nigricans) occupies drier areas, including savanna, semiarid scrub, and bushy hillsides. The northern brownbul (Phyllastrephus strepitans) also prefers scrub, and is often the only bulbul present in the driest parts of its range.

Behavior

Many bulbuls are quite social; some readily join mixed-species groups, others flock with members of their own species. Perhaps the most gregarious bulbul is the spotted greenbul (Ixonotus guttatus). A distinctively colored bird, gray-olive with white spots on its wings and rump, the spotted greenbul is very social, traveling in monospecific groups of five to 50 birds. The groups work their way quickly through trees, never staying long, even if there is plenty of fruit. While briefly at rest they sit very close together on a branch, preening and flicking the wings and tail. The striated bulbul (Pycnonotus striatus), so named because of the yellow-streaking on its underparts and white-streaked upper body, lives in active noisy flocks of six to 15 birds, as does the yellow-browed bulbul (Hypsipetes indicus). The yellow-streaked greenbul (Phyllastrephus flavostriatus), Cabanis's greenbul (P. cabanisi), and Sjöstedt's honeyguide green-bul (Baeopogon clamans) often join mixed-species flocks, traveling right behind or mixed in with other bird species.

Bulbuls can be quite aggressive towards members of their own species, and other species as well. Some, such as the puff-throated bulbul (Criniger pallidus) and the mountain bulbul (Hypsipetes mcclellandii) will aggressively mob birds of prey. If the face-off is against a bulbul of the same species, the threat display may be different than against other birds. Among Pycnonotus, there are roughly three to seven threat displays. These include tail-flicking, tail-spreading, crest-raising, undertail-covert spreading, wing-flicking-and-spreading, and crouch display (the latter may also be an appeasement display). The red-vented bulbul has been observed attacking birds by poking with its bill. The red-tailed greenbul (Criniger calurus) and other Criniger bulbuls will puff out their fluffy beard-like throat feathers, both as a preening gesture and as an aggressive display.

Most bulbuls have distinctive voices, and often the best way of distinguishing similar species is by their song. All over the map, their calls may be jolly phrases of three to six notes (Pycnonotus flavescens), cacophonous explosions of loud discordant babbles (Pycnonotus luteolus), or mewing cat-like calls (Hypsipetes mcclellandii and H. leucocaphalus). Typically, their voices have a gravelly quality, many are chattery and noisy, some with whistles. Very few are actually musical. Most sing in the morning or evening, and many of the more social species will chatter as they forage. The somber greenbul (Pycnonotus importunus) constantly advertises its presence with its distinctive song, a series of clear strong notes "ti-ti-wer cheeocheeo cheeo-wer chi-wee chi-wer chi-wee." A most persistent vocalist, this bird sings all day, even at midday, and all year. The name importunus is from "importunate," named because it sings persistently to the point of annoyance.

Sadly, the species with the most celebrated song, the straw-headed bulbul (Pycnonotus zeylanicus) is now threatened as a result of being highly prized and traded for its voice. Described as "a prolonged series of magnificently warbled notes, richer and more powerful by far than the songs of such celebrated performers as the Nightingale and the blackbird," the song of the straw-headed bulbul is by no means typical of the Pycnonotidae.

The majority of the Pycnonotidae are nonmigratory, either sedentary or only locally nomadic. Banding and recapture records from Asia indicate that some bulbuls remain in the same few hundred yard area for several years. A handful of the cooler-climate, temperate-zone species, such as the black bulbul (Hypsipetes madagascariensis), are partly migratory. Flocks of several hundred of these birds move to southern China in winter.

Feeding ecology and diet

The bulbul diet spans the range of fruits and berries to insects and other arthropods, as well as small vertebrates such as frogs, snakes, and lizards. A few eat nectar and pollen. The jaw apparatus of Pycnonotids is rather generalized compared to other Passeriform birds, and while some Pycnonotids eat mainly fruit or insects, most can and do have a mixed diet. This flexibility may be critical during the dry season: since most bulbuls are non-migratory, they must take advantage of the food sources available within in their range, which can mean shifting to feeding on more plant matter when insects are not as abundant.

Among Phyllastrephus and Criniger, diets tend more toward insects such as caterpillars, dragonflies, wood lice, and ants. The diets of Chlorocichla and Hypsipetes include more fruit, and many of these bulbuls are important for dispersing the seeds of forest plants and as pollinators. Fruit-eating species typically forage in trees, shrubs, and bushes, gathering fruits and berries while perched on twigs and stems. They will often consume smaller fruits whole, and will repeatedly peck fruits with hard, thick walls until they have torn a hole in the outer coat to get at the pulp. Figs (Ficus spp.), are present in the diet of most fruit-eating bulbuls, as well as Schefflera, Musanga, and Lantana berries. These birds can do serious damage to orchards and other cultivated fruit crops. Indiscriminate in their preference for native or exotic berries, fruit-eating bulbuls often disperse noxious, weedy plant seeds.

Most insect-eating bulbuls forage on and among vegetation, but will also sally for insects in the air and hunt along the ground on fallen logs and branches. Many favor caterpillars and dragonflies, and several species have been found attending swarms of army ants. The yellow-bellied greenbul (Chlorocichla flaviventris) frequently forages on antelopes, landing on the animal and grooming its head, ears, and even eyes, presumably searching for small insects in the antelope's coat.

Although most bulbuls are omnivorous, a few specialize in certain foods. Sjöstedt's honeyguide greenbul is closely associated with the small, black wasps Polybioides melaina that build large paper nests in riverbank trees. The bird will tear apart the nests, despite the vicious retaliation of the wasps, and the young birds are fed exclusively on the wax, larvae, and pupae of the insect.

Reproductive biology

Most bulbuls are found in pairs, or in small groups that tend to be family parties and often include juveniles. Mostly monogamous and territorial, except for the yellow-whiskered greenbul (Pycnonotus latirostris), a lekking species, some bulbuls will form groups that defend a large home range together. Both the leaf-love and the swamp greenbul will gather and chorus to defend communal territory. In the case of the swamp greenbul, the loud vocalizations are accompanied by displays of spread wings and tail.

The timing of bulbul reproduction varies greatly, depending on the climate and region. In some areas breeding appears to be tied to rainfall, and many species have two broods per year, usually before and after the monsoon season. Breeding is common year-round in other species, and some African species may breed throughout the rainy season, or after the rains. Most bulbuls are monogamous and territorial, often the pair-bond is maintained year after year. One species, the yellow-whiskered greenbul, has a quite flexible social system, and in high density areas uses leks, but is monogamous and territorial in lower-density areas. There is evidence of cooperative breeding in a handful of species including, the spotted greenbul, the yellow-throated leaf-love, and Ixonotus. Groups of four to six birds will feed the young, usually both in the nest and after leaving it.

Pre-copulatory displays have been observed in some bulbuls, in which the birds chase each other while softly calling. Little is known about the selection of the nest. It is usually built by both parents, although in some cases just the female. Nests tend to be an untidy cup nestled in the fork of a tree. The construction materials vary, but usually include a variety of twigs, rootlets, plant stems, grasses, cobwebs, and hairs. Some species "decorate" the outside of the nest with fern fronds or bark strips. There are usually two eggs per clutch, although there may be as many as five, and there is great variation in the egg color and markings, even within a single species. Some eggs are elongated ovals, others truncated ovate, they may be glossy white, pinkish, lilac, gray, brown, and mauve with scratchy markings, blotches, or spots, sometimes concentrated at one end so the egg appears to be "capped." In some species both parents incubate the eggs, in others the female only, usually for 10–14 days. Young are born naked and are usually cared for by both parents. They are often just given insects at first, even among the species that primarily eat fruit. They generally fledge at 14 days, but as early as seven days in some species.

Conservation status

The primary threat to the Endangered (two species) and Vulnerable (five species) bulbuls is habitat loss, though hybridization and trapping for the caged bird trade are also problematic. The effect of destruction of habitat is especially pronounced because so many of these birds have quite restricted ranges. The Endangered streak-breasted bulbul (Hypsipetes siquijorensis) is endemic to four islands of the Philippines, and while it lives in open areas, forest in some condition appears to be essential to its survival. Forest destruction has severely affected population numbers, and although on the island of Siquijor the remaining four forest patches are now reserves, suitable protection of the rest of its habitat may be critical to its survival. Habitat loss is also a problem for the Nicobar bulbul (Hypsipetes nicobarensis), found exclusively on the Nicobar islands of India. This bird also suffers from competition with the recently introduced Andaman red-whiskered bulbul (Pycnonotus jocosus), which has flourished throughout the islands. Expansion of the Great Nicobar Biosphere Reserve would provide adequate protection for this bird, and controlling the populations of introduced species might also help. The Vulnerable Styan's bulbul (Pycnonotus taivanus), endemic to the lowlands of Taiwan, is also threatened by habitat loss. Also problematic is hybridization with the Chinese bulbul (Pycnonotus sinensis), whose range has expanded to overlap with Pycnonotus taivanus. The only genetically distinct Taiwan bulbuls left live in the coastal mountains. A protected species since 1995, captive-breeding programs and protected areas from which Chinese bulbuls are excluded have been proposed. Habitat loss is also a concern for the hook-billed bulbul (Setornis criniger), confined to the islands of Borneo, Sumatra, and Bangka in the greater Sundas, and the yellow-throated bulbul (Pycnonotus xantholaemus), found exclusively on the southern peninsula of India. Although both birds have some generic protection, preservation of suitable habitat is recommended for both.

The straw-headed bulbul (Pycnonotus zeylanicus) is now threatened as a result of being highly prized for its voice and hence traded as a caged bird. Listed on Appendix II of CITES, some measures have been taken to protect this bird, but it is still widely traded, and captive-breeding programs are subject to theft. Habitat protection might also help as long as areas are guarded.

In addition to habitat protection, the ecology and behavior of these birds must be studied further to better understand survival rates and ecological needs. Efforts to protect these birds by local governments and international groups will do little without the involvement of local people.

Significance to humans

It is not surprising that these vocal birds, many well adapted to human-made habitats, often figure in the folk-tales and songs of the regions in which they live. In each region where bulbuls are common, local lore is often associated with the more conspicuous birds. In Ghana, the noisy swamp greenbul is known as the "talky-talky bird," and children purportedly refuse to eat the flesh of these birds, for fear if they do they will never stop talking. The redwhiskered bulbul is mentioned in many local songs of the Lanna people in Thailand, and is considered a symbol of the old Lanna kingdom. Sadly, like the highly prized straw-headed bulbul, the red-whiskered bulbul is seen less and less in Thailand, as more and more are captured for the southern Thailand bird market. Known as "Nok Krong Hua Juk" (the caged bird with a crest), the red-whiskered bulbul was frequently entered in fighting contests in the early 1960s. Owners would put two of these fiercely territorial birds in a cage until one almost killed the other. In the early 1970s these contests were replaced with the less bloody singing contests, in which two caged birds are placed next to each other and both sing effusively, as though defending their territory. Although the Thai government began requiring permits for owning these birds in 1992, they are still widely traded. As recently as June 2001, 500 captured bulbuls were discovered in transport to the south of Thailand. Seen as a symbol of wealth and prestige, owning these birds has been described as a way of broadcasting the owner's status to the neighborhood, and unless attitudes surrounding their ownership change, they will continue to be captured for the caged bird trade.

Species accounts

List of Species

Common bulbul
Red-vented bulbul
Red-whiskered bulbul
Yellow-vented bulbul
Straw-headed bulbul
Shelley's greenbul
Yellow-whiskered greenbul
Joyful greenbul
Leaf-love
Icterine greenbul
Eastern bearded greenbul
Red-tailed greenbul
White-throated bulbul
Black bulbul
Ashy bulbul
Crested finchbill
Black-collared bulbul
Yellow-throated nicator

Common bulbul

Pycnonotus barbatus

taxonomy

Turdus barbatus Desfontaine, 1789, "Côtes de Barbarie" (= near Algiers).

other common names

English: Yellow-vented bulbul, dark-capped bulbul, black-eyed bulbul, white-eared bulbul, garden bulbul; French: Bulbul commun, Bulbul des jardins; German: Graubülbül; Spanish: Bulbul Naranjero.

physical characteristics

3.6–4.2 in (93–107 mm), 0.8–2.1 oz (23–60 g). Thrush-sized with dark, slightly crested head, dark eye-ring and black bill. Grayish brown upperparts and breast, white belly and white or yellow undertail. Sexes alike, female slightly smaller. Juvenile duller than adult with rusty tones.

distribution

Widespread and common, almost everywhere in Africa south of 20°N, except in dry southwest and the Cape.

habitat

Any wooded or bushy habitat, especially near water.

behavior

Usually in pairs, congregates in fruiting trees with other birds. Not territorial outside breeding season. Song abrupt "quick, chop, toquick"; one of earliest birds to sing in the morning,

starting before dawn and continuing for up to two hours. Communal singing noted following feeding. Fond of bathing and scolding, but not overly aggressive.

feeding ecology and diet

Eats wide variety of wild and cultivated fruits, also flowers, termites, and other insects, sometimes small lizards.

reproductive biology

Monogamous, said to mate for life. Pairs bond with preening ceremony and duet singing. Lays two to five eggs in shallow, thin cuplike nest in bush or shrub, lays twice per season. Incubation 12–14 days, usually by female only. Naked young cared for by both parents, fledging 10–17 days.

conservation status

Not threatened; widespread and common.

significance to humans

None known.


Red-vented bulbul

Pycnonotus cafer

taxonomy

Pycnonotus cafer Linnaeus, 1766. Nine subspecies recognized, extensive hybridization between races. Forms superspecies with six other bulbuls: common P. barbatus, black-fronted P. nigricans, Cape P. capensis, white-speckled P. xanthopygos, white-eared P. leucotis, and Himalayan and sooty-headed P. aurigaster.

other common names

French: Bulbul à ventre rouge; German: Russbülbül; Spanish: Bulbul Ventrirrojo.

physical characteristics

7.8–9 in (20–23 cm), 1.0–2.0 oz (31–59 g). Glossy black chin and throat, slightly tufted head. Back and breast feathers

brownish black edged with gray, appearing scalelike. Rump white, tail brownish black with white tip, undertail ("vent") crimson. Sexes alike. Juvenile resembles adult, but paler; undertail pinkish.

distribution

Native range covers the Indian subcontinent to southwestern China and Polynesia. Established populations in O'ahu, Hawaii.

habitat

Deciduous forest, gardens, and light scrub.

behavior

Keeps in pairs or loose flocks. Bold and tame, can be quarrelsome. Aggressive behavior includes "crest-raising," whereby crest feathers arch over bill and body feathers fluff out. Call a "be-care-ful" or "be-quick-quick," alarm a sharp "peep." Non-migratory.

feeding ecology and diet

Mainly eats fruits and berries, including figs (Ficus spp.), night-shade (Solanum spp.), and Lantana. Also eats insects, often caught on the wing.

reproductive biology

Appears to be monogamous. Male courtship display involves showing erect crimson undertail. Two broods per season, male and female build nest, and both may incubate eggs 10–14 days. Fledge 12 days.

conservation status

Not threatened. Widespread and common throughout range, well adapted to human environments. In Pakistan, building of canals and plantations has increased range.

significance to humans

Fruit-eating a threat to nurseries and agricultural orchards; management taken in Hawaii to prevent spread. Also disperses noxious weed seeds.


Red-whiskered bulbul

Pycnonotus jocosus

taxonomy

Pycnonotus jocosus Linnaeus, 1758. Nine subspecies recognized.

other common names

English: Crested bulbul, red-eared bulbul; French: Bulbul orphée; German: Rotohrbülbül; Spanish: Bulbul de Bigotes Rojos.

physical characteristics

6.6–9 in (17–23 cm), 0.8–1.0 oz (24–31 g). Sooty black crown and erect pointed crest. White chick patch encircled with black line. Brown upperparts, white underparts. Glossy crimson feathers behind eye ("whiskers"). Sexes alike. Juvenile lacks whiskers and crest; head is brown.

distribution

Native range Saudi Arabia to Indian subcontinent to southern China. Introduced in Australia, Singapore. Established populations in southeastern Florida, O'ahu, Hawaii, sighted in southern California.

habitat

Open forest, scrub jungle, cultivated gardens, and orchards.

behavior

Active and noisy, especially in morning and evening. May flock outside breeding season. Somewhat territorial, adult pairs frequently observed with third adult foraging nearby. Call a "petti-grew-kick-pettigrew." Nonmigratory.

feeding ecology and diet

Fruit, also insects, spiders, nectar, and flower buds. Will forage on ground, along buildings, and on tree trunks.

reproductive biology

Probably monogamous. During courtship male lowers head in a bow, while emitting small croaks. Nests well hidden in low vegetation and often left unattended until full clutch (two to five eggs) is laid. Both parents feed young, insects at first, then fruits and berries.

conservation status

Not threatened. Common and widespread throughout range. Florida populations grew from 40 to 50 birds in 1964, to 500 in 1973. Handful of birds escaped in southern California in late 1960s; 15 counted there in Christmas bird count of 1995.

significance to humans

Fruit-eating a threat to nurseries and agricultural orchards, 75% of some orchid plantations destroyed in Hawaii because of bud and flower damage. Blamed for drastic reduction in populations of native Hawaiian white-eyes (Zosterops spp.) on Mauritius I. Management taken in Hawaii to prevent spread. When southern California populations increased so dramatically that they became a threat to citrus crops, the California Department of Agriculture initiated an eradication program that has been partially successful. Also problematic out of range as it disperses noxious weed seeds.


Yellow-vented bulbul

Pycnonotus goiaver

taxonomy

Pycnonotus goiaver Scopoli, 1786. Forms superspecies with P. barbatus, P. nigricans, P. capensis, P. leucotis, P. leucogenys and possibly P. cafer, P. aurigaster.

other common names

French: Bulbul d'Arabie; German: Gelbsteißbülbül; Spanish: Bulbul Capirotado;.

physical characteristics

7.4 in (19 cm), 1.2–1.6 oz (35–46 g). Black head with white eye-ring. Brownish underparts, white in center of belly. Conspicuous yellow undertail (vent). Sexes alike. Juvenile resembles adult, but head brown.

distribution

Turkey, Lebanon, Israel, western Syria, Jordan, Sinai and Arabian peninsulas.

habitat

Open forest, cultivated gardens, orchards, plantations—anywhere with trees, bushes or scrub; will nest quite close to humans.

behavior

Thought to spend time in "duo" with a sibling of same or different sex. Gregarious where food is abundant, hundreds may

flock together outside of breeding season. Active and noisy, squabbling common. Calls various chirping, bubbling, whistling, scolding, occasional mimic of other birds. Nonmigratory.

feeding ecology and diet

Mainly feeds on fleshy fruits, also insects; flying ants, bees, wasps, mole-crickets, worms, and snails.

reproductive biology

Monogamous, pairs remain together all year, often for several years. Two to three broods, nests in bushes or low palms. Two to four subelliptical light violet to pink eggs, with violet or red-brown and gray speckles. Incubation 14 days, fledge 13–15 days.

conservation status

Not threatened. Fairly common throughout range, largest numbers in Israel where range is expanding (few hundred thousand pairs).

significance to humans

None known.


Straw-headed bulbul

Pycnonotus zeylanicus

taxonomy

Pycnonotus zeylanicus Gmelin, 1789.

other common names

English: Straw-crowned bulbul; French: Bulbul á tête jaune; German: Gelbscheitelbülbül; Spanish: Bulbul Bigotudo.

physical characteristics

11.5 in (29 cm). Large bulbul with orange-yellow crown and cheek, white throat lined with black on top, and large bill. Whitish belly and orange rump, olive-green back and wings. Sexes alike. Juvenile duller with brownish head.

distribution

Sundaic range; Myanmar and Thailand through Malaysia, Singapore, Sumatra, Java, Borneo.

habitat

Secondary forest and edge, near water, disturbed areas.

behavior

Found in pairs or family groups up to six birds. Have large territories designated by singing duets (male and female alternating). Very vocal, especially at dawn and dusk. Song a strong, clear, melodious warble.

feeding ecology and diet

Mixed diet of insects, snails, fruits, and berries.

reproductive biology

Little known, may breed year round. Nests of plant material often on boughs overhanging water. Both adults incubate eggs and care for young. Fledge 16 days.

conservation status

Vulnerable. Listed on Appendix II of CITES. Highly prized caged birds; poaching and trapping has led to dramatic population declines and local extinction, habitat loss also a problem. Habitat preservation offers some protection, but capture and trade still permitted in some areas.

significance to humans

Prized songbird worldwide. Known as maki boyah or "alligator bird" from its supposed habit of annoying "alligators," and extending as far up the river crocodiles do.


Shelley's greenbul

Pycnonotus masukuensis

taxonomy

Pycnonotus masukuensis Shelley, 1897, Masuku Range, east-central Africa. Species level taxonomy unclear. Two groups of sub-species recognized: gray-headed western group and green-headed nominate group.

other common names

English: Shelley's bulbul; French: Bulbul des Monts Masukus; German: Shelleybülbül; Spanish: Bulbul de Shelley.

physical characteristics

6.3 in (16 cm); 0.9–1.1 oz (27–31 g). Bright green upperparts, underparts dull olive. Head and neck variable; gray, olive-gray, or olive. Pale eye-ring. Sexes alike. Juvenile resembles adult, but olive parts deeper colored, upperparts duller.

distribution

Endemic resident of middle elevation highlands in east-central Africa. Eastern Zaire to Uganda, Rwanda, western Kenya, eastern Tanzania into Malawi.

habitat

Montane rainforest, riverside scrub.

behavior

Typically found singly or in pairs, may forage in larger groups. Unusually silent for a bulbul, has soft song of "chip, wa-da-tee, chee-tu, ti-wew." Nonmigratory.

feeding ecology and diet

Eats berries and insects. Often uses "treecreeper" foraging method, whereby it starts at the base of a tree looking for insects, works its way up the tree in short hops for 18–30 ft (6–10 m), then flies to base of next tree and starts again.

reproductive biology

Not well known. Nest a strong, shallow cup; lays one or two pinkish, spotted eggs.

conservation status

Not threatened. Fairly common to locally abundant.

significance to humans

None known.


Yellow-whiskered greenbul

Pycnonotus latirostris

taxonomy

Pycnonotus latirostris Strickland, 1844, Fernando Po (now Bioko, Equatorial Guinea). Four races recognized on basis of plumage variation.

other common names

English: Yellow-whiskered bulbul; French: Bulbul à moustaches jaunes; German: Gelbbartbülbül; Spanish: Bulbul de Bigotes Amarillos.

physical characteristics

6.3–7.5 in (16–19 cm); 0.6–1.1 oz (19–32 g). Upperparts and head sooty olive, rump with rufous tinge, back and wings brownish, tail dark reddish brown. Bright yellow moustache stripes on sides of throat. Sexes alike. Juvenile resembles adult, but more dingy brown, no moustache.

distribution

Endemic; central and West Africa.

habitat

Primary and secondary forest, interior and edge.

behavior

Solitary and generally unsociable, usually travels singly. Bathes frequently. Sings continuously, dry jumbled notes; "chop, chip, chirrop, chup, prip, prip" repeated, volume increases throughout song, ends with loud "kick kick." Nonmigratory.

feeding ecology and diet

Omnivorous, eats fruits, berries, many invertebrates including mollusks, woodlice, spiders, frogs, and geckos. Shy when feeding, will fly from undergrowth, gorge on fruits, then return to cover. Often hovers while plucking fruit or gleaning insects from vegetation. Will dig in loose soil for insects.

reproductive biology

Quite variable. In high-density areas uses leks; polygamous and non-territorial with some evidence of cooperative breeding. Before breeding season, males gather and sing at lek sites. Females gather at leks and choose male, female then takes care of young. At lower densities, monogamous and territorial. One to four eggs, incubation by female only 12–14 days. Outside of leks, both care for young.

conservation status

Not threatened. Common and abundant, often most abundant bird in species in range.

significance to humans

None known.


Joyful greenbul

Chlorocichla laetissima

taxonomy

Andropadus laetissimus Sharpe, 1899, Kenya. Two races recognized based on plumage.

other common names

English: Joyful bulbul; French: Bulbul joyeux; German: Dotterbülbül; Spanish: Bulbul Feliz.

physical characteristics

7.8 in (20 cm); 1.5–1.9 oz (43–55 g). One of the most brightly colored bulbuls, yellow-green upperparts, bright yellow chin and throat, golden-green underparts. Olive tail edged with yellow. Sexes alike. Juvenile washed-out brown, greenish under-parts.

distribution

Endemic; Sudan, eastern Zaire, western Uganda, northern Zambia.

habitat

Open parts of primary and secondary forest, forest edges at altitudes of 3,150–7,000 ft (1,050–2,300 m).

behavior

Sociable, forages in small flocks of four to eight birds, with noisy, bubbling, chatter. Song described as pleasant and energetic, call a sharp "chik" or "chak."

feeding ecology and diet

Eats berries and seeds, often forages in groups. Prefers low and intermediate levels, less often in canopy and undergrowth.

reproductive biology

Unknown in wild. In captivity builds typical cuplike nest of rootlets, grasses, and Spanish moss. Young cared for by both parents, fed live insects and fruit.

conservation status

Not threatened. Common locally but patchy distribution.

significance to humans

None known.


Leaf-love

Phyllastrephus scandens

taxonomy

Phyllastrephus scandens Swainson, 1837, West Africa. Closest allies Thescelocichla and Chlorocichla flavicollis, based on bill shape. Two races recognized based on plumage and wing length.

other common names

English: Leaflove; French: Bulbul à queue rousse; German: Uferbülbül; Spanish: Amante de Hojas.

physical characteristics

5.9 in (15 cm); 1.1–1.9 oz (33–53 g). Gray head, back gray-olive, bright, rusty tail, feathers of tail and rump fluffy. Some black bristles on nape of neck and near bill. Belly creamy whitish yellow. Sexes alike. Juvenile mostly olive-gray with rusty wash, chin and underparts white, undertail pale rust.

distribution

Endemic to east central Africa; Sudan, western Gambia, Senegal, Guinea, Sierra Leone, Liberia, Mali, Ivory Coast, Ghana,

Togo, Nigeria, Cameroon, Gabon, southern Congo, Central African Republic, and Zaire.

habitat

Forest and thickets near water.

behavior

Moves in pairs or small flocks; will defend communal territory with chorus. Drops from high perch into streams to bathe, flies back to perch to shake and preen, then drops again. Groups produce loud, raucous chorus.

feeding ecology and diet

Forages in canopy, on ground, and in vegetation for insects and their larvae, also eats small snails, seeds, and berries.

reproductive biology

Territorial during breeding season. Cup-shaped nest suspended in twigs by cobwebs, appears too small for the bird. Incubation by female only.

conservation status

Not threatened. Locally common, though fragmented distribution.

significance to humans

None known.


Icterine greenbul

Phyllastrephus icterinus

taxonomy

Trichophorus icterinus Bonaparte, 1850, Guinea.

other common names

English: Lesser icterine bulbul; French: Bulbul ictérin; German: Zeisigbülbül; Spanish: Bulbul Icterino.

physical characteristics

5.9 in (15 cm); 0.5–0.8 oz (15–25 g). Top of head and upper-parts olive green, uppertail rusty, rump feathers long and fluffy. Chin and throat sulfur yellow, breast and belly yellow washed with green. Reddish tail. Sexes alike. Juvenile resembles adult but upperparts greener and washed brownish breast and throat.

distribution

Endemic east central Africa; Sierra Leone, Liberia, Ivory Coast, Ghana, Nigeria, Cameroon, Equatorial Guinea, Gabon, Congo, Central African Republic, and Zaire.

habitat

Forest, including patchy and swampy areas, plantations.

behavior

Moves in family parties of three to five, up to 12. Group stays together by using nasal call. Group will defend territory and fight with other groups if confrontation occurs. Call a repeated "gur-guk," or nasal "gur-gur-gaaa." Will mob potential predators such as owls.

feeding ecology and diet

Mainly eats insects; often forages in mixed species flocks. Follows small mammals such as squirrels and antelopes, catching insects flushed out by mammals.

reproductive biology

Territorial and monogamous, pairs staying together for several years. Nest a small cup of dry leaves held together by the fungus Marasmius, slung like a hammock in fork of branch. Usually two eggs, incubation 14 days, by female only. When surprised on nest, female will fall to ground and run to distract predator. Both parents feed young.

conservation status

Not threatened.

significance to humans

None known.


Eastern bearded greenbul

Criniger chloronotus

taxonomy

Trichophorus chloronotus Cassin, 1860, Gabon. Forms super-species with C. barbatus.

other common names

French: Bulbul crinon oriental; German:Haarbülbül; Spanish: Bulbul de Lomo Verde.

physical characteristics

7.5–8.3 in (19–21 cm); 1.3–1.5 oz (38–45 g). Large bulbul; breast and head gray, few black bristles on hindneck and mantle. Mantle, rump, and wings yellow-green olive. Tail bright rust-maroon. Chin and throat white, appears puffy and beard-like, creamy belly. Sexes alike. Juvenile resembles adult.

distribution

Endemic central Africa; Cameroon, Gabon, southern Congo, western Zaire, Angola, Central African Republic, western Uganda.

habitat

Lowland rainforest, lower montane forest to 5,900 ft (1,800 m).

behavior

Often occurs in groups; three to five birds, seem to unite by song of leader. Group territory defended by chorus and displays in which "beard" is puffed out. Mournful song of two quavering notes.

feeding ecology and diet

Mainly eats insects and their eggs, some fruit.

reproductive biology

Territorial, possibly a cooperative breeder. Solid cuplike nest decorated with tropical epiphytic fern Microgramma owariensis, which stays green through fledging. Usually two eggs, incubation 14 days by female only.

conservation status

Not threatened. Fairly common in range.

significance to humans

None known.


Red-tailed greenbul

Criniger calurus

taxonomy

Trichophorus calurus Cassin, 1857, Gabon. Two races recognized based on plumage variation.

other common names

English: Red-tailed bulbul; French: Bulbul à barbe blanche; German: Swainsonbülbül; Spanish: Bulbul de Cola Roja.

physical characteristics

7.1 in (18 cm); 0.7–1.2 oz (22–35 g). Head and hindneck olive brown, long black bristles on hindneck. Bright yellow under-parts contrast with olive flanks. White conspicuous "beard," often puffed out. Sexes alike. Juvenile resembles adult but is dull cinnamon on wings.

distribution

Endemic central Africa; Senegal, Guinea, Mali, Sierra Leone, Liberia, Ivory coast, Ghana, Nigeria, Cameroon, Zaire, Gabon, Congo, Angola, Central African Republic, Sudan, and Uganda.

habitat

Forest, forest-grassland mosaic.

behavior

Territorial groups of three through 12. Common in mixed bird flocks, often the leader. Call a weak "chit, chiro-chiro" or whistle "peeyu." Frequently flicks wings and fans tail.

feeding ecology and diet

Mainly insects and insect larvae, also fruits and seeds.

reproductive biology

Territorial breeder, usually two eggs. Incubation by female only; young fed by both parents, fledge 14 days.

conservation status

Not threatened.

significance to humans

None known.


White-throated bulbul

Criniger flaveolus

taxonomy

Criniger flaveolus Gould, 1836. Two races recognized.

other common names

English: Ashy-fronted bearded bulbul; French: Bulbul flavéole; German: Weisskehlbülbül; Spanish: Bulbul Barbudo de Frente Ahumado.

physical characteristics

8.6 in (22 cm). Brownish crest, back olive-brown, lemon-yellow breast and belly, white fluffy throat. Wings and tail have rusty tinge. Sexes alike. Juvenile resembles adult but crest not as prominent and browner belly.

distribution

Himalayas to northeastern Myanmar.

habitat

Bushes and undergrowth in dense forest.

behavior

Noisy, heard more than seen. Often in groups of up to 15 birds which are aggressive in mobbing birds of prey. Prefers lower story of forest. Song a nasal "cheer" or loud clear "teek, da-te-ek, da-te-ek." Frequently puffs out throat and fans tail. Resident, may move altitudinally.

feeding ecology and diet

Mainly berries, also insects.

reproductive biology

Breeds April through July. Builds low nest in undergrowth, usually within 3 ft (1 m) of ground.

conservation status

Not threatened. Locally common.

significance to humans

None known.


Black bulbul

Hypsipetes madagascariensis

taxonomy

Hypsipetes madagascariensis Gmelin, 1789. Four races recognized based on plumage variation.

other common names

English: Madagascar bulbul, Madagascar black bulbul, Comoro bulbul, Comoro black bulbul; French: Bulbul malgache, Bulbul des Comores; German: Madagaskarfluchtvogel, Rotschnabel-Fluchtvogel; Spanish: Bulbul Negro.

physical characteristics

7.8 in (20 cm). Black, with slight crest and forked tail. Bright red legs and feet. Some races have white head, western races have grayer plumage. Sexes alike. Juvenile has less prominent crest, whitish throat and grayish brown plumage.

distribution

Pakistan, India, Bangladesh, Sri Lanka, India, southern China, Taiwan, Hainan, Myanmar, and Indochina.

habitat

Tall forest, shade trees in plantations.

behavior

Gregarious, very noisy, will gather in flocks of several hundred birds. Has a variety of loud screeching, mewing notes, also repeated "pa-chit-chit" or "pip-per-tree." Flight is strong and swift. One of the few migrating bulbuls, resident in some areas, also moves altitudinally.

feeding ecology and diet

Mainly eats insects, also berries. Forages mainly in treetops, moving restlessly from tree to tree.

reproductive biology

Breeds March through September, nest built high in forest trees.

conservation status

Not threatened. Locally common.

significance to humans

None known.


Ashy bulbul

Hypsipetes flavala

taxonomy

Hypsipetes flavala Blyth, 1845. Some authors consider races of chestnut bulbul (Hemixos castanonotus) as races of the ashy bulbul.

other common names

English: Ashy bulbul, brown-eared bulbul, chestnut bulbul; French: Bulbul à ailes vertes; German: Braunohrbülbül; Spanish: Bulbul Ahumado.

physical characteristics

7.8 in (20 cm). Distinctive bird, black crest and mask, brown cheeks and white throat. Back, chest, and tail gray, white belly,

olive-yellow patch on wings. Sexes alike. Juvenile similar, but browner upperparts.

distribution

Himalayas, southwestern China, Southeast Asia, and Greater Sundas.

habitat

Broadleaved forest and edge plantations.

behavior

Found in noisy parties, pairs during breeding season. Puffs out throat feathers like Alophoixos bulbuls. Voice a loud ringing call of four to five notes, also harsh "trrk." Resident, may move altitudinally.

feeding ecology and diet

Forages among trees for berries, nectar, and insects; the latter it catches on the wing.

reproductive biology

Breeds in May and June. Deep, cuplike nest.

conservation status

Not threatened. Locally common.

significance to humans

None known.


Crested finchbill

Spizixos canifrons

taxonomy

Spizixos canifrons Blyth, 1845. Two races recognized.

other common names

English: Finch-billed bulbul; French: Bulbul á gros bec; German: Fimkenbülbül; Spanish: Pico de Pinzón Copetón.

physical characteristics

8.6 in (22 cm). Large, olive-green bulbul with prominent blackish crest and stout, pale-yellow, finchlike bill. Gray fore-head, blackish throat, broad blackish green tail. Sexes alike. Juvenile resembles adult, but browner head and throat.

distribution

Myanmar, Bangladesh, Assam, and south-central China.

habitat

Forest and semicultivated areas up to 9,800 ft (3,000 m).

behavior

Flocks outside the breeding season, often perched on telephone wires. Chattering, bubbling voice; "purr-purr-prruitprruit-prruit." Resident, nonmigratory.

feeding ecology and diet

Forages at all levels for insects, fruit, and seeds.

reproductive biology

Breeds April through July. Distinctive cuplike nest of vine tendrils, usually low in a shrub.

conservation status

Not threatened.

significance to humans

None known.


Black-collared bulbul

Neolestes torquatus

taxonomy

Neolestes torquatus Cabanis, 1875, Chinchoxo, Loango Coast. Taxonomy controversial, some morphological characters ally Neolestes with bulbuls, some ally it with shrikes (Malaconotidae, Laniidae, or Prionopidae). DNA and behavioral data suggest a closer relationship to bulbuls.

other common names

French: Bulbul à collier noir; German: Rüttelbülbül; Spanish: Bulbul de Collar Negro.

physical characteristics

6.3 in (16 cm), 0.7–1 oz (19–27 g). Distinctive, forehead to hindneck gray, black mask continues down neck to form a broad black band across the white breast. Back and tail olive-greenish brown, wings with yellow stripe. Sexes alike. Juvenile resembles adult but duller, crown and neck greenish.

distribution

South central Africa, Gabon, Congo, Angola, Zambia, and Zaire.

habitat

Wooded savanna, grassland.

behavior

Territorial. Found singly, in pairs, or in small groups of three to four birds, will perch on fence posts. Fluid song of "tji-li-li" and "dee-de-de-de-de." Resident.

feeding ecology and diet

Mainly eats insects and fruit, often foraging in tall grasses.

reproductive biology

Solitary nester with some distance between territories (out of range of song). Two eggs laid in untidy nest; young fed by

both parents, mainly fruit. Feigns injury to distract predators from nest.

conservation status

Not threatened. Locally common, though distribution spotty.

significance to humans

None known.


Yellow-throated nicator

Nicator vireo

taxonomy

Nicator vireo Cabanis, 1876, Chinchoxo, Portuguese Congo. Taxonomy unresolved. The genus has been placed in the bush-shrikes (Malaconotidae), other authors place it in the Pycnonotidae.

other common names

French: Bulbul à gorge jaune; German: Gelbkehlnicator; Spanish: Bulbul de Garganta Amarilla.

physical characteristics

5.5 in (14 cm); 0.88 oz (25 g). Upperparts dark green, head tinged gray. Short yellow stripe above the eye, bordered on top with a black line, cheeks grayish. Yellow throat, undertail greenish yellow, yellow tip on tail. Conspicuous yellow wing spots. Sexes alike. Juvenile resembles adult, but greener fore-head and less yellow on throat.

distribution

Central Africa; Cameroon, Gabon, Congo, Angola, and Zaire.

habitat

Lowland forest, especially vegetation near clearings.

behavior

Territorial, lives in pairs, sedentary. Very shy, sings from dense cover. Song of up-and-down whistles with soft in-between notes "po-tyoo-ho-ho-ho-whee, tyoo-ho-ho-ho." Nonmigratory.

feeding ecology and diet

Mainly insects, especially large dragonflies, also caterpillars, beetles, and mantids. Forages in dense clumps of vegetation near clearings.

reproductive biology

Apparently monogamous; holds same breeding territory for several years. Nest often exposed, two grayish eggs spotted with yellow, red, and gray; spots form "cap" on end. Incubation by female, while male stays nearby and sings. Young fed by both parents.

conservation status

Not threatened. Locally common.

significance to humans

None known.


Resources

Books

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

Grimmett, Richard, et al. Birds of the Indian Subcontinent. London: Christopher Helm Ltd., 1998.

Hagemeijer, Ward J.M., and Michael J. Blair, eds. The EBCC Atlas of European Breeding Birds. London: T.& A.D. Poyser, 1997.

Islam, K., and R.N. Williams. "Red-Vented Bulbul (Pycnonotus cafer), Red-Whiskered Bulbul (Pycnonotus jocosus)." In The Birds of North America. 520 (2000).

Jeyarajasingam, A., and A. Pearson. A Field Guide to the Birds of West Malaysia and Singapore. New York: Oxford University Press, 1999.

Keith, S., E. Urban, and C.H. Fry, eds. The Birds of Africa. Vol. IV. San Diego: Academic Press, 2000.

MacKinnon, J., and K. Phillips. A Field Guide to the Birds of China. New York: Oxford University Press, 2000.

Periodicals

Brosset, A. "The Social Life of the African Forest Yellow-Whiskered Greenbull Andropadus latirostris." Z. Tierpsychol. 60 (1981): 239–255.

Cibois, A., B. Slikas, T.S. Schulenberg, and E. Pasquet. "An Endemic Radiation of Malagasy Songbirds is Revealed by Mitochondrial Sequence Data." Evolution 55, no. 6 (2001).

Dowsett, R.J., S.L. Olson, M.S. Roy, and F. Dowsett-Lemaire. "Systematic Status of the Black-Collared Bulbul Neolestes torquatus." Ibis 141 (1999): 22–28.

Narang, M.L., R.S. Rana, and P. Mukesh. "Avian Species Involved in Pollination and Seed Dispersal of Some Forestry Species in Himachal Pradesh." Journal of the Bombay Natural History Society 97, no. 2 (2000): 215–222.

Pasquet, E., L. Han, O. Khobkhet, and A. Cibois. "Towards a Molecular Systematics of the Genus Criniger, and a Preliminary Phylogeny of the Bulbuls (Aves, Passeriformes, Pycnonotidae)." Zoosystema 23, no. 4 (2001): 857–863.

Roy, M.S. "Recent Diversification in African Greenbuls (Pycnonotidae: Andropadus) Supports a Montane Speciation Model." Proceedings of the Royal Society of London B, 264 (1997): 1337–1344.

Organizations

The Bird Conservation Society of Thailand. 69/12 Rarm Intra 24, Jarakhebua Lat Phrao, Bangkok 10230 Thailand. Phone: 943-5965 or 519-3385. E-mail: [email protected] Web site: <http://www.geocities.com/TheTropics/Harbor/7503/ruang_nok/princess_bird.html>

Other

"Zoonomen Nomenclatural Data." January 19, 2002. 18 March 18, 2002. <http://www.zoonomen.net/avtax/frame.html>

Rachel Ehrenberg, MS