Causes of mortality to the endangered Southern Cassowary Casuarius casuarius johnsonii in Queensland, Australia

Abstract

The Southern Cassowary Casuarius casuarius johnsonii is endemic to north-east Queensland, Australia, where it inhabits tropical rainforest. Of the total former cassowary habitat, only 20-25% remains, with much of this under pressure for development. The species is listed as endangered by both the Australian Commonwealth Government and the Queensland State Government. The Queensland Parks and Wildlife Service (2002) estimated 1 500?2500 adult Southern Cassowaries remain. The primary cause of the species' decline is habitat loss and fragmentation, with motor vehicle strikes and dog attacks considered major threats for local populations. The purpose of this paper, therefore, is to quantify the causes of mortality to Southern Cassowaries, including motor vehicle strikes and dog attacks, which have not previously been quantified. We obtained data for 140 cassowary deaths from the Queensland Parks and Wildlife Service, local government councils and persons having experiences with cassowaries. The leading cause of death for 110 cassowaries from 1986?2004 was motor vehicle strikes (55%), and the second leading cause of death was dog attacks (18%). Together, motor vehicles and dogs caused 74% of the cassowary mortalities for which the causes of death could be determined. Seventy-nine of the recorded cassowary deaths (63%) were in the Mission Beach area, suggesting this loca! population is under tremendous pressure. We expect cassowary numbers to continue to decline, especially in the Mission Beach area. We encourage the Commonwealth, State and relevant local governments to fully implement recovery actions. We believe the goal of conserving the Southern Cassowary and its habitat in perpetuity is attainable, but it will require public commitment and political will.