Western grey plantain-eater ©Shutterstock/Natalia Kuzmina

BILL NAYLOR describes some fascinating relatives of the turacos, and adds tips on their management in captivity

ONE of the most common bird sounds of the African forests, is the chorus of calls, often not bird-like, produced by turacos. The green turacos (Tauraco species) vary mainly in the colour of their crests, eye stripes, spots and coloured orbital skin, which are said to aid camouflage in resembling areas of sunlight that penetrate the forest foliage. Although the typical turacos are apple green, there is much variety among the 23 species.

The two species of go-away birds (so-called because of their laughter-like call), and the western grey and eastern grey plantain-eaters lack the colours of the closely related true turacos and inhabit dry open areas, and their calls are not as powerful as those of the forest turacos. All turacos were once referred to as plantain-eaters, yet in fact none feed on plantain, a fruit-bearing plant similar to banana.

A bit different: the plantain-eaters

The western plantain-eater (Crinifer piscator) occupying West Africa, has a distribution four or five times larger than its eastern counterpart. It occurs from Mauritania through Nigeria and then east to the Central African Republic. There is also a small isolated population 200 miles to the south in the Congo. The much smaller range of the eastern plantain-eater (C. zonurus) has become fragmented into three or four areas in the past 50 years, and it now occurs in various eastern countries including Ethiopia, Sudan, Uganda and Kenya. There is a slight overlap in the range of both species in central Africa but, although they are similar in habits and appearance (the eastern species has a shorter crest and a white band across the tail feathers), there is no evidence of hybridisation. (Some species of turacos have hybridised in captivity – obviously, not something to be encouraged.) Grey plantain-eaters are the size of a wood pigeon, with an additional 9in tail. They are impressive birds with a large yellow beak, long legs with large strong feet, and sleek plumage.

Only one species of turaco, the white-bellied go-away bird (Corythaixoides leucogaster) displays sexual differences. DNA feather-sexing is the usual method of establishing gender. Plantain-eaters inhabit savannah, preferably near rivers and waterholes, and are also found in large gardens on the edge of towns. They are usually seen in groups of four or five, either playing “follow my leader” as they run along tree branches, or gliding from tree to tree. The muscles that support the wings are larger than those of the forest turacos and they’re stronger flyers, but like all turacos they are not designed for sustained flight. When plantain-eaters land on a branch, they seem to topple forward and then cock their tail completely up in the air for balance. When taking off, which they prefer to do from a height, they lurch forward hesitantly before launching themselves in the air. Like all turacos, they run head down at speed through trees, particularly when there are long horizontal branches. So adept are they at this that they are often mistaken for squirrels or small monkeys in the tree canopies. The design of their feet (which are similar to those of their relative, the cuckoo) has a feature that gives them considerable agility when running along branches. But unlike cuckoos, which have zygodactyl toe formation (two toes forward and two at the rear), a turaco’s outer toe can be moved to the rear (semi-zygodactyl), giving it added dexterity.

In aviculture

Captive birds require spacious well-foliaged flights, with a long flight path and long horizontal branches. These act as runways where they can sprint or jump from one perch to another. They may use a pond to bathe, but usually rain bathe. Turacos are soft-feathered, long-legged, strong birds and it takes expert handling to restrain them. Ideally, they should be caught in a trap cage rather than netted.

Plantain-eaters are sociable, noisy birds and draw attention with their cackles and other loud raucous calls, especially when one joins the group. Pairs duet and tap beaks together as they call. Eastern plantain-eaters are renowned for their ability to mimic other birds’ calls.

Diet

Food is mainly wild and cultivated fruits. They noisily gather at fruiting trees, often being mistaken for parrots with their large yellow beaks. They feed on figs, mangos, guavas, palm fruits or dates. Flowers, buds and leaves are also eaten. Plantain-eaters, like all fruit-eating (frugivorous) and leaf-eating (foliverous) birds, eat a large volume of food, and in captivity should be fed regularly since they have no crop and food passes rapidly through their digestive system. They are fond of fresh lettuces, provided spiked on branches. Plants grown in the aviary will be sampled and should be identified to avoid those with toxic content. As arboreal birds, they take food most readily from dishes on trays fixed to perches or on stands. Some turaco keepers have found that live food is eaten; others that their birds are not interested. But invertebrates like beetles, snails, termites are eaten in the wild. Turacos are susceptible to iron storage disease, and grapes and oranges, which can upload iron, are either fed sparingly or omitted.

Display and mating

A main cause of turaco mortality in captivity is male aggression towards females during the breeding season. This can happen even with established pairs when females are not receptive. Chasing is a natural part of courtship behaviour but if bullying occurs then intervention is necessary. The eastern grey plantain-eater is rarer in collections than the western species, which has been bred a number of times. The first breeding in the UK was in 1989. Nesting in the wild usually occurs in the dry season in May. In courtship, the male feeds the female and displays by swooping down from a height, while the hen bird extends her tail and wings. The pair’s body language includes raising their crests and puffing out their neck and body feathers. Plantain-eaters are often depicted with fluffed-up feathers, yet the plumage is normally tight and sleek.

The nest can be located from 4.5-15m (15-50ft) high, but is often in the tree canopy, usually near the end of a leafy branch. It’s a substantial, untidy structure built mainly of twigs, resembling a pigeon’s nest. In captivity, trays or baskets are placed in nesting locations as foundation for a nest and are readily used.

Both parents incubate between two and four glossy grey eggs for 27 days. The youngsters have grey down, unlike forest turacos which have black down, and fledge at 21 days old. Dry straw is often provided along with twigs as nest material, but the interior of the nest should not be too slippery or a chick can develop splayed legs. The youngsters are fed on regurgitated plant and fruit material. Pinkies or low-iron softfood can be added to increase protein content.

Fruit and veg fed in captivity rarely possesses the nutrients of that eaten in the wild and fortifying with protein, vitamins and minerals is probably necessary. However, Houston Zoo, which has success with plantain-eaters, stresses that plant material is a vital rearing food. Cotswold Wildlife Park, which successfully bred nine western plantain-eaters, put this down to the parents feeding nestlings regurgitated parts of rosebay willowherb (Chamaenerion angustifolium). The young climb among branches adjacent to the nest before they can fly.

Bill Naylor has enjoyed a 40-year career in ornithology and aviculture.

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