Breeding biology of the Australian Spur-winged Plover

Abstract

The increase of the Australian Spur-winged Plover during the present century in Tasmania has coincided with the increased acreage of improved pasture. Nests are in short vegetation and mostly on farm land but farming operations, apart from trampling by stock, do not cause serious losses. Eggs, clutch-size, incubation and fledging periods, and breeding success are described. Interesting results are that Tasmanian eggs are significantly larger than those from Lake Bathurst, NSW. The median and mode of clutch-size of the species are 4 (mean 3.53) and do not vary from year to year; eggs from a clutch and complete clutches are often lost, mostly by trampling by stock. Incubation is about 28 days; the eggs normally assume a fixed position in the nest; hatching may be at the same time or spread over several days. The young can fly when 6–7 weeks old although this varies even within a brood. Brood capture was observed. The development of the young is given. Breeding success is analysed in .a way applicable to all species with nidifugous young, and total breeding success was between four and nine young per 100 eggs laid. The onset of laying has been correlated with both mean temperature and rainfall. Photoperiodism may not be the ultimate factor controlling the breeding cycle but it may be an important proximate factor in Tasmania.