Birds are the most accomplished of all flying animals and evolved from reptile-like ancestors. Birds, like mammals, are endothermic (warm blooded) vertebrates, however, unlike most mammals, they lay eggs. Birds also have several adaptations for flight, including wings, feathers, a light skeleton with very light, hollow, but strong bones, well-developed pectoral (chest) muscles, small organs, air sacs and a highly efficient respiratory system. The bird class, Aviformes, has about 180 families and over 9,000 species. All birds must preen their feathers in order to fly – conditioning the feathers for optimum operation in the air and, in many birds, waterproofing.
Johannesburg Zoo has 36 families of birds, comprising about 140 species. The two families most represented in the Zoo are the Anseriformes and Psittaciformes.
The Anseriformes are the waterfowl - ducks, geese and swans. Most waterfowl are known for their webbed feet and waterproof feathers. The most unusual member of this group in the zoo, the South American screamer, has a turkey-like body and partly-webbed feet. It is really unusual and seldom recognised as being part of the waterfowl order.
Beautiful swans from Europe and Australasia include the Mute swans, Whooper swans and Black swans, all with characteristic long necks. The waterfowl collection is extensive, with both indigenous and exotic birds. The most beautiful birds are theMandarin ducks and Shelducks, the indigenous Whistling ducks and Cape teal. Watching the waterfowl can be a restful occupation in the zoo.
The other large family in the Zoo is the Psittaciformes or parrots. These conspicuous, usually brightly coloured birds populate most of the world’s warmer areas. The Zoo has a number of macaws, cockatoos and African parrots in the collection. Many of these can be seen in the large David Lewis Aviaries surrounding the Sasol Walk-through Aviary.
Cranes include important indigenous species that are endangered as a result of habitat loss and poisoning. These beautiful birds, including the national bird – the Blue Crane can be found in a number of areas in the Zoo. The Zoo also houses the Grey Crowned Crane, and the critically endangered Wattled Crane. The Johannesburg Zoo is home to the Wattled Crane Recovery Project, whereby captive populations are being managed in an effort to support the small wild population of less than 300 birds. More information on this project can be requested from firstname.lastname@example.org
Another important conservation project at the Johannesburg Zoo involves the endangered Ground Hornbill. The numbers of these magnificent hunters of the veld are dwindling in the Kruger National Park and efforts are under way to assist through captive breeding.
Other large birds in the Zoo include the storks, such as marabou storks, the brightly marked saddlebill storks and the smaller white storks. Flamingoes are long-legged birds with specialised filtering bills, represented in the Zoo by Greater, Caribbean and Lesser Flamingos.
Flightless Ratites - ostriches, emus and rheas. The only flightless birds currently in the Zoo are the South American Rheas.
The ostrich is the largest of all birds and is from Africa. The male is mainly black and incubates the eggs at night, whereas the female is brown and incubates eggs during the day. Both males and females have white feathers on their wings. Ostriches can weigh up to 150kg and can run up to 60km/h. Emus are from Australia and are very similar to ostriches but are smaller and darker and they lay dark green eggs. Rheas are from South America and are the smallest of these three species.
Raptors or birds of prey are a diverse group. These accomplished predators can be seen in various areas in the Zoo and include Verraux’s eagles and owls.
Many indigenous owls are on display, including the Spotted Eagle owls also Marsh, Grass, Barn, Wood, White-faced and Scops Owls. The vulnerable Grass owl is endemic to South Africa, meaning it occurs naturally only in southern Africa. The very large South African species - the Verraux’s /Giant Eagle owl can be found alongside the smaller species. They are commonly seen in the Kruger Park, nesting on old Hamerkop nests. One exotic owl species is the Eurasian Eagle Owl, arguably the largest owl species.
Owls have very special adaptations. They have well-developed hearing and large eyes. Owls turn their entire heads to see around them because the eyes are so large that they cannot turn in their sockets like those of a human. Owls, like most birds cannot smell, but rely mainly on hearing and sight to capture prey. They have silent flight to help them get close to their prey.
Other carrion-eaters in the Zoo are the Cape vultures and other vultures, also part of a conservation project. They are often the innocent targets of poisoning – they get poisoned accidentally when farmers target predators like caracal. Other threats to many big bird species are power lines, where the birds collide with the cables or get electrocuted when they land on the structure.
Game-birds or ground dwelling birds are also an extensive family represented in the zoo, from the indigenous Guinea fowls and Francolins to the exotic and brightly coloured pheasants and free roaming Peacocks. The David Lewis Aviaries and Sasol aviary have an array of birds to impress most visitors, from those already mentioned to the smaller and unusual species such as the Scarlet Ibis from South America.
The Sasol walk-through aviary is a popular bird enclosure. The start of this aviary was quite modest. An outdoor theatre structure from Joubert Park was brought to the zoo in 1986 and transformed into a walk-through aviary. It soon became clear that the aviary needed to grow, so surrounding satellite aviaries were added around the main structure. This project was supported by David Lewis, who was involved in the City’s Centenary projects in 1986, but who died before he could see the final results of his efforts. The surrounding aviaries were named after David Lewis and house mainly exotic species such as Blue-fronted amazons, Blue-and-Gold macaws, Black swans, Whooper swans, African grey parrots and pheasants.
The central walk-through aviary houses indigenous species such as Crested guinea fowl, Galah Cocatoos ,Bald and Glossy ibis. The educational value of the aviary was seen by Sasol, who sponsored a bird guide booklet, posters in the aviary and a thatch-roofed education area, which was fittingly named The Sasol Wing. This area is used for educational talks and small, secluded functions. This aviary lends itself to many peaceful hours for bird lovers in an extremely tranquil environment. The educational and recreational value of the bird collection is as important as the conservation value.
Lastly, the fish eating Pelicans must be mentioned because of their impressive size and their remarkable throat pouch for scooping up fish. These residents are now moved in our big Sasol wing Aviary because their feathers are able to regrow very fast, and that means they don’t qualify to stay on Zoo’s wetland area anymore because they will fly away.