Studies of waterfowl (Anatidae) in north Queensland. 5. Breeding

Abstract

The 12 species of waterfowl that bred either frequently or occasionally in north Queensland during 1959-1969 nested almost entirely during the wet seasons, usually December-April, when suitable habitat was abundant and widespread and vegetation cover for nests and available food for young were at a maximum. Nesting requirements and habits were generally similar for all species except the colony-nesting magpie goose (Anseranas semipalmata (Latham)) and black swan (Cygnus atratus (Latham) ). Results of reproduction nevertheless were broadly similar because colonies were readily destroyed by flooding. Reproductive activity in alt species was curtailed during 1961, when there was relatively We rainfall; clutch and brood sizes were comparatively small and there was little eventnal population increment. Many young birds were added to the population, mainly as a result of greater survival of young in the first broods, after the extensive wetseason flooding of 1968, when there was prolonged reproductive activity.