WATERFOWL USAGE OF WETLANDS IN THE SOUTH-EAST ARID INTERIOR OF WESTERN-AUSTRALIA 1992-93

This paper reports the use by 35 waterfowl species of 23 wetlands in t he south-east interior of Western Australia following the wettest year on record for much of the region. The majority of the wetlands are sa line with individual wetlands varying from brackish to hyper-saline ov er relatively short periods that markedly affected use by waterfowl. S ome freshwater wetlands supported more species (but not individuals) t han saline ones, although the salt lakes were significant functioning wetlands supporting greater numbers of certain species. Onset of breed ing for early breeding species is two months after the rainfall event. Probably a short period of maximum biological productivity follows in itial filling which also triggers breeding enhanced by the fact that t hese wetlands were all dry previous to this rainfall event. Breeding d id not appear to extend into a second season despite adequate water le vels and was not inhibited by low winter temperatures.