White-backed Duck
White-backed Goose ( Thalassornis leuconotus )
The white-backed Pfeifgans ( Thalassornis leuconotus ), also called White-backed Duck, one belonging to the subfamily of Whistling Ducks Art is systematically it is placed therefore to the birds ducks ( Anatidae ). Although it is closely related to the actual Pfeifgänsen ( Dendrocygnini ), it differs from them by its enormously specialized adaptation to diving. Therefore, it was placed in the past, often to the rudder ducks ( Oxyurini ); but it is a case of convergent evolution. Sometimes there are two subspecies, the African white-backed Pfeifgans ( Thalassornis leuconotus leuconotus ) and the Madagascar Weißrückenpfeifgans ( Thalassornis leuconotus insularis ).
Appearance
White-backed Whistling Ducks appear short and stocky. The birds have a mottled brown plumage, a black speckled with yellow beak and green-gray legs. Males and females look alike. Both are about 45 inches long and weigh about 625-800 grams. They are anatomically well adapted to diving and can stay under water and there travel up to 65 meters for about half a minute. When swimming, the tail lies flat on the water.
Nutrition
Mainly, the white-backed Pfeifgans of plant parts, especially seeds and leaves, the young animals fed but also of caterpillars and insect larvae. The roots of water lilies are also popular. They are brought on by diving in shallow waters to the surface.
Habitat
Range of the white-backed Pfeifgans is southern Africa from Ethiopia to the Cape of Good Hope and West Africa from Chad to Senegal. Specimens of the subspecies insularis live exclusively on Madagascar. White-backed Whistling Ducks prefer to live in calm waters with lush vegetation, such as reed lakes, swamps and river marshes that protect them from predators.
Reproduction
Mated for life build both partners together to breeding season, which may be time very differently depending on water levels in the breeding area, the nest, which is applied mostly on small islands or in the reeds and is rarely lined with feathers. Often several pairs nest close together. The female then lays about four to ten light brown colored eggs. The approximately one-month brooding and the subsequent rearing is carried out by males and females again jointly. After about two to four months, the young are fledged.
System
The closer relationships within the Whistling Ducks are as follows:
Tüpfelpfeifgans (D. guttata)
Kubapfeifgans (D. arborea )
Gelbbrustpfeifgans (D. bicolor)
Sichelpfeifgans (D. eytoni )
Wanderpfeifgans (D. arcuata )
Zwergpfeifgans (D. javanica )
Witwenpfeifgans (D. viduata )
Bellied (D. autumnalis )
White-backed Pfeifgans ( Thalassornis leuconotus )
Endangering
The subspecies Thalassornis leuconotus insularis is threatened by hunting, habitat loss and invasive species entrained. The West African populations of Thalassornis leuconotus leuconotus go back to the number of individuals, but are not considered to be threatened.