Musophagiformes (Turacos and Plantain Eaters)

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Musophagiformes

Turacos and plantain eaters

(Musophagidae)

Class Aves

Order Musophagiformes

Suborder Musophagae

Family Musophagidae

Number of families 1


Thumbnail description
Medium-sized to large birds with short, rounded wings, rather long tail and a conspicuous erectile crest

Size
16–30 in (40–76 cm)

Number of genera, species
8 genera; 23 species

Habitat
Forest, woodlands, and savannas

Conservation status
Endangered: 1 species; Vulnerable: 1 species; Near Threatened: 1 species

Distribution
Sub-Saharan Africa

Evolution and systematics

Turacos are an old family of birds whose ancestry and evolution are undeniably linked to the retraction and subsequent expansion of Africa's forests and savannas. The limited fossil record prevents the simplest reconstruction of turaco evolutionary history. Material from the Oligocene of Bavaria and Egypt, and from the Miocene of France and Kenya, indicates that turacos occurred on both sides of the Sea of Tethys some 25–30 million years ago, prior to the collision of African and European land masses.

The phylogeneric relationships between turacos and other birds have attracted considerable debate over the past 50 years or more, with most authors of modern bird classification giving turacos sister family status with cuckoos. This almost traditional association of the two groups was long based on their shared zygodactyl arrangement of toes, wherein two toes project forward and two toes project backward. However, in turacos the fourth, or outer toe, is normally held at right angles to the main axis of the foot when perched or moving, while in cuckoos, the fourth toe is permanently reversed. Recent DNA analyses suggest that turacos have no close living relatives.

Currently 23 species of turacos are recognized, grouped within eight genera and three subfamilies. Corythaeolinae contains the giant monospecific Corythaeola, long considered an isolated genus without any close relatives. The Musophaginae contains 17 forest species within four genera, while the remaining five savanna species of the Criniferinae are grouped in three genera.

Physical characteristics

Turacos must surely rank among the most colorful and striking of all African birds. Of the 23 species, the 17 forest and woodland species have lustrous, iridescent green, blue or violet plumage with brilliant red primaries conspicuous in flight. The five savanna species are predominantly gray or brown in color, while the giant of the family the great blue turaco (Corythaeola cristata) is largely greenish blue and yellow, with chestnut posterior underparts, but lacks any red in the wings. With the exception of the great blue, all turacos are medium-sized birds (16–20 in; 40–50 cm), with a fairly long tail and rather short, rounded wings. Most have a prominent erectile crest, the shape, size and color of which is extremely variable. The sexes are alike in all species, though in the white-bellied go-away-bird (Criniferoides leucogaster) the bill color in males is dark, while that of the female varies from pea-green to pale yellow. Most species have a rather short, strong bill with a curved culmen (ridge of upper mandible), that is ridged in a few species. In the two Musophaga species, the culmen extends back to form a brightly colored frontal shield. All species within the genus Tauraco have bright red orbital skin, some with well-developed eye wattles. In nearly all species feathers of the head and breast lack barbules, and are hairy in texture. The two plantain-eaters are somewhat unique in having the elongated feathers that produce the crest present only on the back of the head and on the nape, and that are somewhat bristly and stiff to the touch.

The presence of two copper pigments, red turacin and green turacoverdin is unknown elsewhere in the animal kingdom. Normally such bright colors in birds are produced by melanins and lipochromes, or by diffraction of light from the surface of feathers, but not so in the Musophagidae. Turacoverdin is present in several species that lack turacin, but turacin does not occur in the absence of turacoverdin. The amount of turacoverdin is directly related to the luxuriance of the habitat in which they occur, being most developed in the tropical forest species, and least developed or absent in the savanna species. An earlier belief that these pigments were water soluble and washed out in rainstorms is untrue.

Distribution

Turacos are currently confined to sub-Saharan Africa, being absent only from the dry waterless regions of the central Kalahari, the western Cape, and the Horn of Africa. Being poor fliers, turacos are unable to reach offshore islands, but are present on both Bioko (formerly Fernando Po) and Zanzibar, which were joined to the African mainland in recent geological times.

Habitat

Turacos occupy all arboreal habitats south of the Sahara Desert from sea-level to over 9,800 ft (3,000 m). All types of forest, woodlands, as well as bushed and wooded grasslands, and the semi-arid acacia scrub are home to turacos, go-awaybirds, and plantain-eaters. Recently many species have adapted to well-wooded suburban parks and gardens.

Black-billed (Tauraco schuettii), Knysna (T. corythaix), Livingstone's (T. livingstonii), and the great blue turaco are the most ecologically versatile species, occurring in both lowland and montane forests. With the montane forests now recognized as important centers of endemism in Africa, five allopatric turacos: Hartlaub's (T. hartlaubi), white-cheeked (T. leucotis), Prince Ruspoli's (Tauraco ruspolii), Bannerman's (T. bannermani), and Ruwenzori turaco (Ruwenzorornis johnstoni) are restricted to quite small and in some cases highly threatened habitats. Elsewhere the green (T. persa), yellow-billed (T. macrorhynchus), and Fischer's turaco (T. fischeri) are typically lowland forest and forest edge species. Schalow's (T. schalowi), purple-crested (Gallirex porphyreolophus), red-crested (T. erythrolophus), white-crested (T. leucolophus), violet (Musophaga violacea), and Ross's turaco (M. rossae) occupy gallery and riverine forests with seasonal periods spent in adjacent and more open woodlands. Outside of these forests and woodlands, the northern savannas of sub-Saharan Africa are occupied by the two plantain-eaters, and the eastern and southern savannas by the three go-away-birds.

Behavior

Most turacos are shy, strongly territorial, and gregarious, often remaining in family groups for long periods. While the forest species are generally highly sedentary, some gallery and riparian turacos are frequently recorded at fruiting trees in areas they are normally absent from for several months. Similarly the plantain-eaters and go-away-birds of the savannas and acacia woodlands regularly undertake local movements in response to fluctuating food and water supplies.

All forest species spend much of their time within a designated core territory, which is itself surrounded by a closely guarded peripheral feeding area. However, they regularly visit forest patches beyond their territory borders for food, often traveling long distances to reach a particularly favored fruiting tree. They invariably approach and leave it in single file and in total silence. Territory size varies considerably, ranging from around 0.7 mi2 (2 km2) for the great blue and Ross's turacos in western Kenya, to an average of 10 acres (4 ha) per pair for Schalow's on the Nyika Plateau in Malawi, and 37 acres (15 ha) per pair for the yellow-billed turaco in Gabon.

All turacos are highly vocal, and the raucous calling of each of the 15 species of green turacos (Tauraco spp.) combined with the loud, resonant "kok-kok-kok-kok" calls of the great blue are among some of the most characteristic sounds of the African forests, just as the plaintive, nasal calls of the go-awaybirds are so typical of the African savannas. A day in the life of a turaco begins around dawn when an individual calls and others nearby respond immediately. Individuals and family groups soon begin feeding in fruiting trees, but as the day warms up, they spend long periods preening and basking in the morning sun. Where two or more species occur together, the calls of one will frequently initiate aggressive responses from others. Such "counter-singing" is commonly encountered between yellow-billed and green turacos in Gabon, Knysna, and purple-crested turacos in South Africa, Schalow's and purple-crested in Malawi, and black-billed and Ruwenzori turacos in Rwanda. As evening approaches most turacos move towards their favored roosting trees, and again periods of prolonged calling may be a feature of such journeys to the roosting site.

The harsh, barking calls of each of the 15 species of green turacos are extremely similar, differing only slightly in tempo and pitch. For most it is a loud, raucous barking, often preceded by a higher-pitched hoot, the function of which is simply territorial advertisement, only in the Ruwenzori turaco is there any major variation. The two Musophaga species (Ross's and violet turacos) engage in long choruses of deep, rolling, gargling "cou-cou-cou-cou-cou-cou" notes which tend to run together producing a continuous, pulsating, almost monkey-like chorus, and which is even more pronounced when two or more individuals call in unison. The three go-away-birds utter a series of plaintive, nasal call notes, some of which are described by many as if saying "g'way, g'way." The two plantain-eaters call in a series of high-pitched laughing or cackling "cow-cow-cow" or "how-how-how" notes.

Feeding ecology and diet

Turacos consume large quantities of both wild and cultivated fruits and are important agents in the dispersal of seeds of indigenous trees throughout sub-Saharan Africa. Several species also eat flowers and leaves, caterpillars, moths, beetles, snails, slugs, and termites, particularly during the breeding season. Although the English name of plantain-eater is used for two species, and was formerly given to the family as a whole, neither plantains nor cultivated bananas form any part of the diet of any turaco in the wild.

Throughout the equatorial forests of West and Central Africa, fruits of the parasol (Musanga) and waterberry (Syzygium) trees are particularly favored, and in areas where Polyalthia, Cissus, and Ficus species have regular heavy fruitings, these also provide the staple foods of most forest turacos. Leaves and flowers seem to be particularly important to the great blue, constituting on average more than 25% of their overall diet. Elsewhere, in the acacia savannas of Africa, the go-away-birds and plantain-eaters have a far more varied diet consisting not only of fruit, but also large quantities of leaves, flowers, seed pods, and emerging termite alates. Water is a major requirement, and in southern Africa groups of 20–30 gray go-away-birds (Corythaixoides concolor) have been recorded at favored water sources. A gray go-away-bird has been observed carrying water to a nearby fledged young. Gray go-away-birds have also eaten clay, the only recorded example of geophagy among turacos.

Reproductive biology

The onset of the rainy season stimulates courtship activity among all turacos, resulting in much calling and the chasing of one another from tree to tree, mutual feeding, opening and closing of the bill, raising and lowering of crests, bowing and flirting of the tail, and in the green forest species, much wing-spreading to display the bright crimson primaries. All breed solitarily, and while most species are probably monogamous, some go-away-birds have assistants to help feed the young and defend the territory. Such "helpers" are likely offspring from a previous brood.

All species build a flat and often flimsy nest of sticks, very similar to those of pigeons and doves (Columbidae). Nests of the forest turacos are placed in thick foliage of trees or shrubs 16–66 ft (5–20 m) above ground, while those of go-away-birds and plantain-eaters are often in acacias, at times unconcealed. Clutch size of savanna species is two or three eggs; all other turacos normally lay two eggs. The rounded eggs vary in color from white or grayish-white to cream, glossy bluish-white, or pale ivory-green. Incubation is by both sexes, and varies from

22–23 days in the smaller green turacos, to 27–28 days in the plantain-eaters and go-away-birds, and 29–31 days in the great blue. The hatchlings are at a relatively advanced stage of development with a thick coat of black, brownish, or gray down, and in some species a well-developed wing claw. All nestlings are fed by regurgitation, and in most species the parents swallow the chick's feces as soon as discharged. Young become extremely active between two and three weeks, and commonly leave the nest to climb about in nearby branches long before they can fly. Most make their first attempts at flight at 28–35 days, but remain dependent upon their parents for some time longer, with young great blue turacos being fed for up to three months after leaving the nest.

Conservation status

As of 2000, only three species of turacos are listed by the IUCN as facing some degree of threat. However, with the rate of habitat loss in Africa accelerating all too quickly, species with restricted ranges have become the most highly vulnerable and require constant monitoring. The indiscriminate trapping and export of thousands of turacos annually has had its effect on several species. While a number of turacos have been listed under CITES (Convention on International Trade in Endangered Species), it is debatable whether existing legislation has had any beneficial effects on the birds. Under IUCN criteria (in 2001) for assigning threatened status, Bannerman's turaco is listed as Endangered, Prince Ruspoli's is Vulnerable, and Fischer's is Near Threatened.

The last turaco species to be described, Bannerman's turaco, is restricted to small, fragmented forest patches in the Bamenda highlands of western Cameroon, and is one of the most threatened birds in Africa. Between 1965 and 1985 indiscriminate forest clearance reduced its habitat by half, and today its survival is only possible if the existing forests on Mts. Oku and Ijim are guaranteed lasting protection. While it is estimated that fewer than 2,000 individuals remain in the Bamenda highlands, prospects for its long-term survival are bleak. The people living in and around its forested habitats walk through these forest patches daily to eke out a subsistence that will ultimately result in more forest being cleared. The population, numbered at 250,000 in the 1990s, will grow to half a million or more by 2025, and the numbers of Bannerman's turaco will be further reduced. In southern Ethiopia, Prince Ruspoli's turaco has an equally restricted range in the mixed broad-leaf and acacia woodlands that in some areas are becoming seriously degraded by continuing human encroachment and demands for wood fuel. Equally alarming is the impact of human encroachment on the remaining coastal forests in East Africa. Fischer's turaco has an extremely restricted and diminishing range in southern Somalia, coastal Kenya, and northeastern Tanzania. On the island of Zanzibar an endemic subspecies is facing habitat loss of unprecedented proportions.

Significance to humans

Turacos have long been exploited by humans for food and their feathers. For centuries turaco feathers have adorned ceremonial headdresses of African royalty and elders. In Kenya, feathers from Schalow's, Ross's, and Hartlaub's turacos have been regularly seen in ceremonial headdresses of the Masai tribe, while in Cameroon a red flight feather from Bannerman's turaco in an elder's black hat indicates his position as a "chindoh" or traditional council member. Elsewhere, particularly in parts of southern Africa, the gray go-away-bird is considered something of a pest, being highly destructive to the soft-skinned fruits and vegetables grown on large commercial plantations.

The demand from the cage-bird trade around the world has resulted in large scale trapping and export of turacos, most notably from Guinea, Sierra Leone, Liberia, Ghana, Togo, and Tanzania. Loopholes in legislation are ruthlessly exploited, so that for every 10 turacos that survive the journey from Africa to a captive environment, 50, maybe hundreds, may perish in the process, due largely to the often cruel and appalling methods of capture and the resulting stress of confinement. In an effort to halt such exports, several responsible zoos and aviaries around the world are establishing captive breeding programs involving several species of turacos. Turaco husbandry has made great advances in recent years, and it is hoped that in the near future, legislation will be in place to ensure that only birds bred in captivity will be available to other zoos, aviaries, and turaco breeders.

Species accounts

List of Species

Great blue turaco
Ross's turaco
Ruwenzori turaco
Purple-crested turaco
Hartlaub's turaco
Gray go-away-bird
White-bellied go-away-bird
Western gray plantain-eater

Great blue turaco

Corythaeola cristata

subfamily

Corythaeolinae

taxonomy

Musophaga cristata, Vieillot, 1816, Sierra Leone. Monotypic.

other common names

English: Blue plantain-eater; French: Touraco geant; German: Riesenturako; Spanish: Turaco Gigante.

physical characteristics

28–30 in (70–76 cm); male 1.9–2.1 lb (857–949 g), female 1.8–2.7 lb (822–1,231 g). The giant of the family, readily identified by its overall greenish blue and yellow plumage, blue-black crest, bright yellow bill, tipped red, long wide tail, and chestnut posterior underparts. Juveniles similar but duller and with much smaller crest.

distribution

Equatorial Africa from Guinea Bissau, Liberia and Ivory Coast east through Nigeria, Cameroon, Gabon, and Congo to Uganda, Rwanda, Burundi, northwest Tanzania, and western Kenya.

habitat

Lowland and montane forest from sea-level to over 7,000 ft (2,400 m).

behavior

Generally found in pairs or family groups, feeding in tall forest trees. Highly territorial and vocal, with their loud guttural "cow-cow-cow-cow-cow" calls and deep, resonant purring notes a feature of the African rainforests.

feeding ecology and diet

Primarily a fruit eater, but also consumes large quantities of leaves and flowers when certain fruits become scarce. Recorded eating algae.

reproductive biology

A solitary breeder, generally laying two pale blue-green eggs in a nest that is nothing more than a platform of sticks with a shallow rim, but well hidden in a tall, leafy forest tree. Both sexes incubate for approximately one month, and nestlings climb outside of the nest a month later. The young fledge at around five to six weeks, but remain dependent on the adults for up to three months.

conservation status

The most widespread of all turacos. Although not globally threatened, continuing forest destruction, hunting, and trapping for export will result in a decline in numbers in many parts of West Africa, most notably in Guinea, Liberia, Sierra Leone, Ivory Coast, Nigeria, and Togo.

significance to humans

Widely considered a delicacy over much of West Africa, as well as being a highly sought after species in the traditional fetish markets of Nigeria.


Ross's turaco

Musophaga rossae

subfamily

Musophaginae

taxonomy

Musophaga rossae, Gould, 1851, West Coast of Africa (precise locality unknown). Monotypic.

other common names

English: Lady Ross's violet plantain-eater; French: Touraco de Lady Ross; German: Rossturako; Spanish: Turaco de Ross.

physical characteristics

20–21 in (50–53 cm); male 13.8–15.7 oz (390–444 g), female 13.9–14.0 oz (395–398 g). A striking large, glossy violet-blue turaco, with conspicuous crimson crest, yellow bill and frontal shield, while in flight, the brilliant red primaries contrast sharply with the dark violet-blue body and tail. Juveniles lack frontal shield; crown of head is black with small red patch in the center.

distribution

Widely distributed in central and eastern Africa from the Dem. Rep. Congo, Uganda and western Kenya south to eastern Angola and northern Zambia. Extralimital populations occur in the northern Central African Republic, Cameroon, northeastern

Gabon, and at scattered localities along the Caprivi Strip and in the Okavango Delta region of northwestern Botswana.

habitat

Typically a bird of the gallery forests and riverine woods from around sea level to over 5,000 ft (1,750 m), but reaching 8,200 ft (2,500 m) in montane forests along the southern Sudan/northeastern Uganda border.

behavior

Generally found in pairs or family groups, with much calling between individuals and nearby groups. Some seasonal movement into deciduous thickets and Brachystegia woodlands at onset of the rains in Zambia and Botswana, presumably related to the emergence of fruiting trees. Highly territorial and aggressive towards other turacos when breeding.

feeding ecology and diet

Largely frugivorous, but diet frequently supplemented with flowers, shoots, and flying termites. Will also feed on cultivated fruits such as guavas and loquats where available.

reproductive biology

One or two almost cylindrical creamy white eggs are laid in a rather flimsy, pigeon-like platform of twigs, generally well hidden in dense tree foliage, mistletoe, or creepers. Incubation shared by both sexes for 24–26 days. On hatching the young are covered in dark brown down. Nestlings begin to climb out of the nest into nearby branches after 24 days, and generally leave the nest tree after a month, but remain with the adults for several weeks.

conservation status

Although not considered a threatened species, as all African forests and woodlands continue to shrink and give way to subsistence agriculture, it is the gallery and riverine forests that are being destroyed most rapidly. Formerly traded in some numbers from East and Central Africa, but trade appears to have declined in recent years. Habitat loss is the most serious threat facing this species.

significance to humans

Feathers, particularly from the red primaries, are used to decorate ceremonial Masai headdresses in southwestern Kenya.


Ruwenzori turaco

Ruwenzorornis johnstoni

subfamily

Musophaginae

taxonomy

Gallirex johnstoni Sharpe, 1901, Ruwenzori Mountains, Uganda. Two subspecies.

other common names

English: Johnston's mountain turaco; French: Touraco du Ruwenzori; German: Kammschnabelturako; Spanish: Turaco del Ruwenzori.

physical characteristics

17–18 in (43–46 cm); 8.2–8.7 oz (232–247 g). A brilliant green and violet blue turaco with red primaries conspicuous in flight. Short glossy green or purplish blue crest on hindcrown; nape dull crimson, chin and throat blue black. Distinctive peachyred patch on an otherwise green breast; wings and tail deep violet blue. Shape of bill highly distinctive with a rounded culmen rising to a narrow bony ridge between the eyes. Eyelids scarlet surrounded by highly variable loral areas; these being emerald green and fully feathered in kivuensis, but simply bare yellowish skin with some pinkish red below and behind the eyes in nominate birds.

distribution

R. j. johnstoni: Ruwenzori mountains and at Mount Kabobo (Dem. Rep. Congo), where originally described as T. j. bredoi. R. j. kivuensis: Montane forests of the Itombwe and Kivu Highlands (Dem. Rep. Congo), Virunga volcanoes, Nyungwe Forest (Rwanda/Burundi), and southwest Uganda.

habitat

Endemic to high mountain forest between 6,500 and 11,000 ft (2,000–3,400 m) on either side of the Albertine Rift.

behavior

Occurs in pairs or small family groups, with many individuals remaining paired and aggressively defending territories throughout the year. Particularly favors the bamboo zones and areas dominated with epiphytes and lianas.

feeding ecology and diet

Eats primarily fruits and berries, but large quantities of leaves and flowers are also consumed. Where sympatric with the great blue and black-billed turacos, all three species can frequently be found feeding alongside each other in the same fruiting tree.

reproductive biology

One or two dull grayish-white eggs are laid in a nest that is little more than a small platform of sticks, generally 10–15 ft (3–5 m) above ground in a bamboo thicket. Incubation and fledging periods for this species remain unknown.

conservation status

Not globally threatened, but with continuing habitat degradation as a result of prolonged civil unrest throughout its restricted range, it remains a species in need of constant monitoring.

significance to humans

Although no trade reported in this species, it has long been hunted for food in the Democratic Republic of Congo.


Purple-crested turaco

Gallirex porphyreolophus

subfamily

Musophaginae

taxonomy

Corythaix porphyreolophus Vigors, 1831, Durban, South Africa. Two subspecies.

other common names

English: Purple-crested lourie; French: Touraco a huppe splendide; German: Glanzhaubenturako; Spanish: Turaco Crestimorado.

physical characteristics

16–18 in (40–46 cm); 7.7–11.6 oz (218–328 g). A striking iridescent green-and-violet turaco with a dark violet purple crest and conspicuous red flight feathers. Upper back and breast green washed with rose pink in nominate birds, but lacking any wash in chlorochlamys. Lower back and wings grayish blue, tail glossy violet blue. Posterior underparts pale bluish slate in nominate birds, but dull greenish gray in chlorochlamys. Juveniles similar to adults but red primaries duller and less extensive.

distribution

G. p. porphreolophus: South Africa from Natal and eastern Transvaal north to Mozambique and Zimbabwe, intergrading with chlorochlamys in the Zambezi Valley. G. p. chlorochlamys: Zambia east to Malawi and northern Mozambique, and north to Tanzania, southeastern and central Kenya, Burundi, and Rwanda.

habitat

Typically in moist woodlands, but locally in miombo and well-timbered suburban parks and gardens. Generally below 5,000 ft (1,500 m), but reaches 6,000 ft (1,800 m) in central Kenya.

behavior

Generally in pairs or small family groups, but flocks of up to 20 birds have been observed at favored fruiting trees or watering points. At onset of the rains in Zimbabwe, there is a marked dispersal away from riverine woods into the surrounding miombo woodlands.

feeding ecology and diet

Mainly fruits and berries, while in many parts of southern Africa will readily feed at suburban bird feeders.

reproductive biology

Two or three rounded, glossy white eggs are laid in a flimsy, unlined platform of sticks 10–30 ft (3–10 m) above ground, well concealed among matted tree creepers or dense parasitic growth. Both sexes incubate for 22–23 days; hatchlings are covered with a thick grayish brown down. The young become active at about three weeks, when they begin to move out of the nest and into the surrounding branches, and make their first flight at around 38 days.

conservation status

Locally common in many parts of southern Africa, but in eastern Africa the population is declining due to continuing loss of habitat and in some areas indiscriminate trapping.

significance to humans

During the early part of the twentieth century this species was hunted by Zulu warriors in southern Africa for their red flight feathers, which were used as adornments when going into battle. Today the same red primary feathers can be seen in the headdresses of African royalty and elders in Swaziland.


Hartlaub's turaco

Tauraco hartlaubi

subfamily

Musophaginae

taxonomy

Corythaix hartlaubi Fischer and Reichenow, 1884, Mt. Meru, northern Tanzania. Monotypic.

other common names

English: Blue-crested plantain-eater, black-crested turaco; French: Touraco de Hartlaub; German: Seidenturako; Spanish: Turaco de Hartlaub.

physical characteristics

16–17 in (40–44 cm); 6.9–9.7 oz (195–275 g). A dark iridescent green turaco with brilliant red primaries conspicuous in flight. Rounded bushy crest and nape glossy blue-black; chin, cheeks, neck, mantle, throat, and breast dark green; lower back, folded wings, and tail deep violet blue; thighs and belly dull blackish washed with green. Prominent white patch in front of the eye separated from a white line extending from gape to ear coverts by a black loral patch and narrow black line immediately below the eye. Orbital ring and bare skin behind the eye red. Juveniles similar to adults but duller and with less red in primaries.

distribution

An East African endemic centered around the Kenyan Highlands, extending into north Tanzania at Loliondo, Longido, mounts Meru and Kilimanjaro, the Pares and West Usambara mountains. It reaches east Uganda at mounts Elgon, Moroto, and Morongole.

habitat

Evergreen montane forests between 4,550 and 10,500 ft (1,400–3,250 m), as well as in well-timbered suburban parks and gardens around Nairobi and other central Kenyan towns.

behavior

Typically in pairs or family groups, congregating in groups of up to 20 individuals at favored fruiting trees. In many areas pairs defend a core territory year round, and each day work a well-defined feeding route within territorial boundaries. Flight appears weak and labored with much flapping and gliding, and generally for only short distances. Courtship displays by the male are noisy and involve much fanning and jerking of the tail, raising and lowering of the crest, and half opening of the wings to display crimson flight feathers. Once the pair bond is established, the pair engages in frequent bill rubbing, and the male offers food to the female at frequent intervals.

feeding ecology and diet

Primarily eats fruits and berries, but will also consume flowers, caterpillars, moths, and beetles. Appears particularly attracted to black or dark red fruits, and captive birds readily devour black grapes.

reproductive biology

Two rounded dull white eggs are laid in a shallow platform of loosely interlaced twigs, some 7–25 ft (2.5–8 m) above ground, and generally among thick tree foliage. Incubation is by both sexes for 22–23 days. Newly hatched chicks are covered in black down, and for the first few days are fed on regurgitated caterpillars and fruit pulp. At 17–18 days the nestlings are able to climb all over the nest tree, rarely being in the nest itself, and are able to make their first flight at around 28 days.

conservation status

Although fairly common in Kenya, the northern Tanzanian population has been seriously impacted by years of indiscriminate trapping and export, resulting in high mortality and diminishing populations in several areas. Tanzania has been the sole exporter of wild-caught birds, and despite annual quotas of 200 birds, this has been disregarded for many years.

significance to humans

A popular cage bird with large numbers in zoos and aviaries in the United Kingdom, Europe, North America, Mexico, and the Far East, with considerable breeding success, thus reducing the need for the continued importation of wild birds from Tanzania.


Gray go-away-bird

Corythaixoides concolor

subfamily

Criniferinae

taxonomy

Corythaix concolor Smith, 1833, inland of Port Natal (Durban), South Africa. Four subspecies.

other common names

English: Gray lourie; French: Touraco concolore; German: Graularmvogel; Spanish: Turaco Unicolor.

physical characteristics

18–20 in (46–51 cm); 7.1–12.0 oz (202–340 g). Adult has entire head and body warm smoky gray, being palest around the eyes, and darkest on the chin, throat, tail, and primary coverts. In most forms there is a suffusion of olive green on the breast, though this is hardly noticeable in the field. Crown feathers are long and partly decomposed, forming a slightly shaggy crest that varies in length, and which can be raised or depressed at will, but when flattened, projects well beyond the back of the head. Juveniles similar to adults but with shorter crest and a buffy tinge to the overall appearance.

distribution

Locally common throughout the northern parts of South Africa from Zululand and the eastern Transvaal north to Mozambique, Zimbabwe, Zambia, Malawi, and southeastern Tanzania, and west to Botswana, Namibia, Angola, and southern Dem. Rep. Congo. Up to four races have been recognized, though racial variation is difficult to interpret. The presence of darker birds in the east and paler ones in dry western areas may to be attributed to a cline with differing characteristics among birds due to changes in the environment.

habitat

Typically a bird of the drier, open woodlands and savannas of southern Africa, with a marked preference for those areas dominated by acacias. While principally a species adapted to dry woodlands, it is very much dependent on water, a factor that accounts for its absence from otherwise suitable habitat such as the dry central and southwest Kalahari. In recent decades has readily adapted to suburban parks and gardens around Johannesburg.

behavior

Generally found in pairs, small family groups, or parties of three to 20 birds, hopping, climbing, and bounding about in trees and bushes with much dexterity. Alert and inquisitive, it will often perch on the topmost branches of trees with a marked upright posture, raising and depressing its crest, and jerking its tail as it calls. Flight is strong and direct with alternating gliding and flapping. Movements of up to 40–60 individuals or more have been observed on several occasions, possibly in response to fluctuating food or water supplies. At all times will react aggressively toward other turacos, chasing them away from fruiting trees, bird feeders, and water, yet readily sharing such resources with other birds such as pigeons, parrots, barbets, orioles, and starlings.

feeding ecology and diet

Feeds primarily on fruits, but will also consume large quantities of flowers, foliage, and termites. In many areas considered a pest by gardeners and commercial horticulturalists due to its destructive consumption of cabbages, lettuce, legumes, and soft-skinned fruits.

reproductive biology

One to four, but usually three white or pale grayish-blue eggs are laid in a flimsy, pigeon-like platform of sticks some 15–20 ft (3–6 m) above ground, generally in an acacia tree. Both sexes incubate for 26–28 days. Newly hatched young are covered in dense brown or grayish brown down. They become active at 14–18 days, clambering around the branches of the nest tree, taking their first short flights at about 23 days, and finally becoming fully fledged at around four weeks. On several occasions three to six birds have been recorded attending to and feeding young in the nest. Such "helpers" are probably young birds from an earlier brood.

conservation status

A wide-ranging and generally common species throughout its range. Currently no known threats to either its habitat or overall population.

significance to humans

Long considered a bird of ill repute among the Kalahari bushmen, who complain bitterly that it deliberately warns wild animals of their approach.


White-bellied go-away-bird

Criniferoides leucogaster

subfamily

Criniferinae

taxonomy

Chizaerhis leucogaster Ruppell, 1842, southern Ethiopia. Mono-typic.

other common names

English: White-bellied plantain-eater; French: Touraco a ventre blanc; German: Weissbauch-Larmvogel; Spanish: Turaco Ventriblanco.

physical characteristics

19–21 in (48–53 cm); 6.0–8.8 oz (170–250 g). A large gray-and-white turaco with a stiff and pointed brownish gray crest rising from the forehead. Upperparts, sides of head, chin, and entire neck and breast gray, rest of underparts white. Black

flight feathers with white bases form a conspicuous white speculum in flight; tail black with a broad white median band. Bill blackish in male, pea green in the female (sometimes yellowish when breeding). Juveniles similar to adult but browner.

distribution

Widely distributed in the arid and semi-arid savannas of eastern and northeastern Africa from Somalia, Ethiopia, and southern Sudan south through northern Uganda, northern and eastern Kenya to central Tanzania.

habitat

Typically in hot, low acacia savannas from sea level to 4,550 ft (1,400 m), but reaching 6,500 ft (2,000 m) on the Laikipia Plateau in central Kenya.

behavior

A common and often conspicuous bird, occurring singly, in pairs, or family groups. Flies somewhat slowly with rather rapid wingbeats and much gliding. Like all turacos becomes extremely agile once landed. A noisy bird with a variety of sheep-like bleating calls.

feeding ecology and diet

Flowers, leaf shoots, and young acacia seed pods form an important aspect of their diet, as do the fleshy ripe fruits of Balanites trees and bushes. Will also readily eat exotic fruits as Carica (papaya) and Psidium (guava) if offered at bird feeders. Flowers and foliage of many dry country plants are consumed in vast quantities, as are their fruits whenever available.

reproductive biology

Two or three glossy pale bluish green eggs are laid in a rather small, flat structure of twigs some 10–40 ft (3–12 m) above ground, generally in an acacia or Balanites tree. Incubation is by both sexes for 27–28 days. On hatching the young are covered in dark grayish brown down with a patch of bare skin around the eyes. They are fed a regurgitated pulp by both parents, and on a few occasions other birds have been observed "helping" at the nest. Fledging period remains unrecorded.

conservation status

Not globally threatened, and with no major threats to either its habitat or populations. With some trapping and export reported from Tanzania, it is recommended that it be listed in Appendix 3 of the CITES legislation.

significance to humans

None known.


Western gray plantain-eater

Crinifer piscator

subfamily

Criniferinae

taxonomy

Falco piscator Boddaert, 1783, Senegal. Monotypic.

other common names

English: Gray plantain-eater; French: Touraco gris; German: Schwarzschwanz-Larmvogel; Spanish: Turaco Gris Occidental.

physical characteristics

19–20 in (48–51 cm); 11.6–12.3 oz (330–350 g). A predominantly gray-and-white turaco with a large lemon-yellow bill. Adults have forehead, crown, lores, cheeks, chin, and throat dark brown. A shaggy dark brown nape crest with whitish edges is unique among turacos. Upperparts silvery gray with dark brown spots; the lower breast, belly, flanks, thighs, and under tail coverts are white with heavy brown streaking, particularly on the thighs. Primary feathers black with a central third of the

inner webs white, forming a conspicuous white wing patch in flight; tail largely blackish brown. Juveniles less silvery gray on upperparts and lack any crest on an otherwise all dark head.

distribution

Widespread throughout the sub-Saharan acacia steppe, wooded savannas, and cultivation from southern Mauritania, Senegambia, Guinea, and Sierra Leone east to Nigeria, Cameroon, Lake Chad, and the Central African Republic. Also disjunctly along the Congo River south of Stanley Pool.

habitat

Typically from sea level to 4,225 ft (1,300 m) in open wooded savannas and thorn scrub with scattered tall trees, while in the more semi-arid areas it keeps mainly to the thicker stands of vegetation and riparian woods. In many areas has adapted to cultivation and the neighborhood of villages, particularly where favored fruiting trees are available. Has readily adapted to parks and gardens in many countries.

behavior

A gregarious species, occurring generally in pairs or small groups. Always a noisy bird, with one seldom perching or joining its mate without a great deal of commotion. Pair bonding is exceptionally strong, with much calling, bowing, tail fanning, and food exchanges taking place during all greeting displays. Courtship display flights are always noisy and impressive. Less agile in running along branches than other turacos, as a result tends to fly more, albeit for short distances with much gliding alternating with rapid wingbeats. Frequently comes to ground to drink.

feeding ecology and diet

A wide variety of wild and cultivated fruits are eaten, together with flowers, seed pods, and invertebrates, while the name plantain-eater is erroneous. Flowers constitute a major part of the diet, possibly as high as 50% in some individuals. Favored fruits include figs, mangos, and guavas, also the wild date (Phoenix reclinata), oil palm fruits (Elaeis guineensis), and the widely introduced neem (Azadirachta indica).

reproductive biology

Generally two grayish white or pale bluish white eggs, oval and slightly glossy, are laid in a fairly substantial platform of dry sticks some 12–50 ft (4–15 m) above ground in a leafy tree. Incubation is by both sexes for 27–28 days, and on hatching the young are covered in grayish-brown down. Fledging period for this species unrecorded.

conservation status

Not globally threatened, being widespread and locally abundant over much of the West African savannas, reaching a density of one bird per 2.5 acres (per hectare) in some areas of Acacia scorpioides woodland in Senegal. Commonly hunted and trapped for export in several countries, most notably Guinea.

significance to humans

A highly sought after species in the traditional fetish markets of Nigeria.


Resources

Books

del Hoyo, J., A. Elliott, and J. Sargatal, eds. Handbook of the Birds of the World. Vol.4, Sandgrouse to Cuckoos. Barcelona: Lynx Edicions, 1997.

Fry, C.H., S. Keith, and E.K. Urban. The Birds of Africa. Vol. 3. New York: Academic Press, 1988.

Periodicals

Moreau, R.E. "Some Aspects of the Musophagidae." Ibis 100 (1958): 67–112; 238–270.

Veron, G., and B.J. Winney. "Phylogenetic Relationships Within the Turacos (Musophagidae)." Ibis 142 (2000): 446–456.

Organizations

International Touraco Society. Brackenhurst, Grange Wood, Netherseal, Nr Swadlincote, Derbyshire DE12 8BE United Kingdom. Phone: +44 (0) 1283 760541. E-mail: [email protected]

Donald Arthur Turner

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