Over 2000 islands lie off the Kimberley coast of Western Australia. These islands retain populations of flora and fauna that have been isolated from the mainland for between 8-10 thousand years.
The fragmented flora and fauna populations on these islands are potentially at risk due to increased pressure from tourism, introduced species and commercial exploitation of natural resources such as iron ore and natural gas.
The Western Australian Museum and The University of Western Australia have conducted three intensive short-term surveys on 35 islands located off the Kimberley coast to document the taxonomic status of island populations relative to their mainland counterparts.
Using molecular markers, the Museum and University have examined the degree of genetic and morphological (size and shape) differentiation and assessed the impact of isolation on genetic diversity.
This approach been greatly beneficial to determine both the conservation value of the plants and animals on the islands, and the potential for their management.
The research has also allowed an appraisal of the evolutionary processes on the islands to determine if populations are relics from when the islands were connected to the mainland, or if the populations are derived from adjacent islands.
The endemic Kimberley Rock-rat Zyzomys woodwardi, the Northern Quoll Dasyurus hallucatus and the Northern Striped Skink Ctenotus inornatus have been documented on islands, and analysis has revealed greater genetic similarity to their mainland counterparts compared to those on nearby islands.