African Jacana

African Jacana - Długoszpon Afrykański 

 Botswana, Okavango Delta, 2012

Description

African Jacanas (Actophilornis africanus) are waders in the family Jacanidae. The most conspicuous characteristic of these birds are their huge, grey feet and claws which enable them to walk on floating vegetation, especially lily pads. They are also very good swimmers and divers. They are about 30 cm long, but females are larger than males. They have chestnut upper parts with black wingtips, rear neck, and eye stripe. The under parts are also chestnut in the adults, only in juveniles they are white with a chestnut belly patch. The blue bill extends up as a coot-like head shield, and the legs and long toes are grey. The sexes look alike, but the female is a bit larger than the male.

Habitat

Jacanas are found worldwide within the tropical zone, and this species is found in sub-Saharan Africa. The African jacana is not migratory, but extremely nomadic, often in connection with changing water levels; in wet years, birds may show up on pans, from which the species has been absent for several years.

Voice

Sounds of African Jacana

Diet

African Jacanas feed on insects and other invertebrates picked from the floating vegetation or the surface of the water. The African jacana mainly feeds on insects and worms, but also other arthropods, including spiders and crustaceans, and mollusks. Seeds are sometimes taken. Foraging similar to the Wattled Jacana, though the species may also catch flies and other flying insects.

Reproduction

African Jacanas breed throughout sub-Saharan Africa. It is sedentary apart from seasonal dispersion. It lays four black-marked brown eggs in a floating nest.

The jacana has evolved a highly unusually polyandrous mating system, meaning that one female mates with multiple males and the male alone cares for the chicks. Such a system has evolved due to a combination of two factors: firstly, the lakes that the jacana lives on are so resource-rich that the relative energy expended by the female in producing each egg is effectively negligible. Secondly the jacana, as a bird, lays egg and eggs can be equally well incubated and cared for by a parent bird of either gender. This means that the rate-limiting factor of the jacana's breeding is the rate at which the males can raise and care for the chicks. Such a system of females forming harems of males is in direct contrast to the more usual system of leks seen in animals such as stags and grouse, where the males compete and display in order to gain harems of females.

The parent that forms part of the harem is almost always the one that ends up caring for the offspring; in this case, each male jacana incubates and rears a nest of chicks. The male African Jacana has therefore evolved some remarkable adaptations for parental care, such as the ability to pick up and carry chicks underneath its wings.

Did you know?
African Jacana have a polyandrous mating system, in which females can have multiple male partners. After mating and egg laying, the female leaves the nest site and may look for another mate while the male incubates and raises the young.

Photos by others

Credits

Wikipedia, Birds of Brazil (Wildlife Conservation Society)