Behaviour and social organization of the African Jacana Actophilornis africanus.

Abstract

The behaviour, nesting, food resources and mating system of the African Jacana Actophilornis africanus were studied at Muzi Swamp, northern KwaZulu-Natal and at Darvill Sewerage Works, KwaZulu-Natal. African Jacanas show highly polyandrous behaviour associated with a marked reversed sexual size dimorphism. A high clutch loss was recorded because of predation and weather conditions. Contact behaviour was recorded, which is unusual in Charadriiformes. Vocalization and visual displays were distinctive and closely related to territorial and sexual behaviour. Unlike the Wattled Jacana Jacana jacana, the African Jacana practises male guarding behaviour. Rich food concentration in the African Jacana habitat was shown by field tests and this may be a reason for this species evolving in a floating environment. The presence of simultaneous polyandry in the African Jacana was analyzed mathematically and by computer modelling in order to determine possible advantages of polyandry.