The dry season diurnal behaviour of the Madagascar Teal Anas bernieri at Lake Bemamba

Abstract

The behaviour of the globally threatened and little known Madagascar Teal was studied at Lake Bemamba, western Madagascar in July 1992. At least seven pairs and two single birds were observed. The pairs were tightly bonded and aggressively defended feeding space from conspecifics. Paired birds were dominant over and more aggressive than single birds. Paired males and females appeared to show similar levels of aggression. Copulation was observed but no other courtship behaviour, and there was no evidence of nesting activity. During daylight hours (0645 h to 1810 h), 80% of time was spent feeding. The amount of time spent resting increased notably between 1000 and 1300 h, but over 55% of time was spent feeding at all times. Madagascar Teal are active dabblers in shallow water, moving almost constantly. Of time spent feeding, 68% was conducted on foot and 32% swimming. Detailed descriptions of feeding and agonistic behaviour are made. The species has markedly different behaviour, habitat use and life cycle to the other six species of Anatidae present in the lake. There also appear to be important differences in behaviour in comparison with the other, closely related, Austral teal. However, it is likely that Madagascar Teal have the long term pair bonds typical of Austral teal.