Chapter 5 Feeding Ecology of the Australian Raven on Rottnest Island

<strong>Chapter</strong> 2
Terrestrial Avifauna <strong>of</strong> Rottnest Island
2.1 Introduction and Aims
Since its occupation by European settlers almost 200 years ago, Rottnest Island has been
coveted for its natural beauty and idealised lifestyle. As a result, <strong>the</strong> natural and
anthropogenic histories are well documented. Many residents <strong>of</strong> Perth are sentimental
about <strong>the</strong> Rottnest environment and its recreation opportunities. However, <strong>the</strong> island has
not always been a place for locals and tourists looking to relax. Rottnest was formerly used
as a pastoral lease, penal outpost and later a military base, which along with <strong>the</strong> more
recent development <strong>of</strong> facilities for tourists, has considerably changed <strong>the</strong> composition <strong>of</strong>
<strong>the</strong> flora and fauna species. It no longer resembles what would have been experienced by
<strong>the</strong> first settlers in <strong>the</strong> 1830s.
In this chapter I summarize <strong>the</strong> history <strong>of</strong> Rottnest Island and examine how <strong>the</strong> changes to
vegetation and landscape use have influenced <strong>the</strong> distribution and abundance <strong>of</strong> bush birds.
The changes in <strong>the</strong> status <strong>of</strong> bush birds on Rottnest Island is examined through a review <strong>of</strong>
<strong>the</strong> literature <strong>of</strong> previous bird studies and historical records, and is compared to recent
surveys and observations.
2.1.1 Geography & geology
Rottnest Island is located 17km northwest <strong>of</strong>fshore from Fremantle, Western Australia
(Figure 2.1). The island has a temperate climate, with temperatures slightly lower than
those recorded on <strong>the</strong> adjacent mainland, and an average annual rainfall <strong>of</strong> 563mm (Bureau
<strong>of</strong> Metrology 2011). It is part <strong>of</strong> a chain <strong>of</strong> Quaternary limestone islands and reefs along <strong>the</strong>
continental shelf opposite Perth, which also includes those in Cockburn Sound (Garden,
Carnac and Penguin Islands) (Playford 1988) to <strong>the</strong> south, which were separated from <strong>the</strong>
mainland approximately 7000 years ago (Glenister, Hassell and Kneebone 1959). Rottnest is
<strong>the</strong> largest (1900 ha) <strong>of</strong> <strong>the</strong>se island and measures 10.5km from east to west. It is
predominantly open heath and dunes with 10% <strong>of</strong> <strong>the</strong> area occupied by large salt lakes
separating <strong>the</strong> eastern and western parts <strong>of</strong> <strong>the</strong> island (Playford 1983).
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