Ecological Impacts of Metallic Starling Colonies in Tropical Queensland, Australia

Abstract

Animal aggregations – whereby large numbers of animals come together at one place at one time – can have dramatic impacts on individuals, populations and ecosystems. In many cases, they are also unique forms of animal interaction, and include some of the world’s most recognised wildlife spectacles. But despite these traits, the causes and consequences of animal aggregations are often poorly understood. One such case involves large colonies of metallic starlings (Aplonis metallica) that nest together in emergent rainforest trees in northern Queensland, Australia. Starling colonies attract a diverse assemblage of wildlife, which utilise resources dropped by the starlings. Remarkably, these animal aggregations have never been described, and thus broader questions about their influence on ecosystems in tropical Australia remain unanswered. My thesis aims to describe this system, begin to answer some of these questions, and elucidate broad patterns common to other aggregations of animals worldwide. It focuses on the starlings themselves and the reasons for their choice of colonial nest sites. It also explores the lives of the animals using the starling colonies, with specific chapters on native birds and feral pigs, invasive cane toads, and the ways these species mediate the influence of starling colonies on the surrounding ecosystem.