Petrogale penicillata (Brush-tailed Rock-wallaby) IUC Status: Vulnerable The range of this species is seemingly quite large, following the Great Dividing Range from about 100km north west of Brisbane down to the Gampians in northern Victoria. Yet, even with a range that large, the species is not considered secure, largely because of habitat fragmentation.
When populations become isolated from each other it has a twofold impact:
First, populations that suffer declines cannot be boosted from individuals from outside. Should the local population die out, there’s no way that habitat can be repopulated.
Second, genetic diversity of small populations shrinks, especially when disasters like fire, drought or disease take out large numbers of individuals at a time. This shirking diversity leaves the population less able to adapt to pressures from disease or the environment.
Population diversity and fluidity is critical for overall sustainability. Our system of carving up the country and building fences and roads is un-natural, creating islands of habitat surrounded by ecological deserts.
This problem is
accelerating the demise of koalas in South East Queensland, in spite of the huge resources being thrown at the problem. Nothing short of restoring habitat and bridges between them can fix it....