Chapter 5 Feeding Ecology of the Australian Raven on Rottnest Island

1.3 Research Questions
The overall aim for this study is to describe <strong>the</strong> ecology <strong>of</strong> <strong>the</strong> <strong>Australian</strong> <strong>Raven</strong> on Rottnest
Island. In particular, I will assess whe<strong>the</strong>r <strong>the</strong> <strong>Australian</strong> <strong>Raven</strong> is a predator <strong>of</strong> nesting bush
birds on Rottnest Island, and how this impacts on bush bird communities.
Specific questions are:
1) What is <strong>the</strong> distribution <strong>of</strong> bush birds on Rottnest Island?
2) What is <strong>the</strong> abundance and distribution <strong>of</strong> <strong>the</strong> <strong>Australian</strong> <strong>Raven</strong> on Rottnest Island?
3) Does <strong>the</strong> <strong>Australian</strong> <strong>Raven</strong> predate on bush birds on Rottnest Island?
4) What is <strong>the</strong> feeding ecology <strong>of</strong> <strong>the</strong> <strong>Australian</strong> <strong>Raven</strong> on Rottnest Island?
5) How does predation by <strong>the</strong> <strong>Australian</strong> <strong>Raven</strong> impact on bush birds on Rottnest
Island?
I use observational and experimental methods to investigate <strong>the</strong>se questions. The research
is presented here with each question answered in an independent chapter. The findings <strong>of</strong>
each chapter are linked in <strong>the</strong> final Discussion (<strong>Chapter</strong> 6) where I will answer Question 5.
The chapters are described below:
<strong>Chapter</strong> 2 Reviews <strong>the</strong> history <strong>of</strong> Rottnest Island and describes <strong>the</strong> changes to <strong>the</strong>
avifauna through a literature review <strong>of</strong> published surveys <strong>of</strong> Rottnest
avifauna over <strong>the</strong> last 100 years;
Examines <strong>the</strong> current distribution <strong>of</strong> bush birds on Rottnest Island using
observational data collected during this study and external data sources.
<strong>Chapter</strong> 3 Introduces <strong>the</strong> biology and ecology, in particular <strong>the</strong> distribution and
abundance, <strong>of</strong> <strong>the</strong> <strong>Australian</strong> <strong>Raven</strong> in <strong>the</strong> context <strong>of</strong> Rottnest Island using
observational data collected during this project.
<strong>Chapter</strong> 4 Investigates nest predation by <strong>the</strong> <strong>Australian</strong> <strong>Raven</strong> using an artificial nest
experiment.
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