Australia’s islands have biodiversity values that can be disproportionate to their size. Consider Barrow Island, which lies off north-west Western Australia and is home to 24 species that occur nowhere else on Earth (of which five are mammals).
But the conservation value of islands extends beyond their indigenous species. Consider the case of Bald Island, off the coast from Albany in the south of Western Australia. Noisy scrub-birds had been presumed extinct until they were heard singing near a picnic area in Two Peoples Bay National Park near Albany. The rocky landscape had protected a small number of breeding pairs – perhaps fewer than 50 – from wildfires but the remaining population was under constant threat from fire and foxes. In the mid-1990s a few individuals were translocated to a series of nearby release sites, including Bald Island. Not long after, the mainland populations were devastated by a series of wildfires that killed 92% of the mainland population.
Bald Island has since also become home to the world’s second population of Gilbert’s potoroo, which previously existed as a single population restricted to an area of 5 km2. It too was threatened by wildfire.
Many of our islands, like Barrow Island, support rare and endemic taxa. And many, like Bald Island, offer a last refuge to species that have been wiped out on the mainland or provide...
