The introduction and spread of noxious aquatic fauna and flora can be particularly damaging to the health of our waterways. Once introduced, these invasive species often can't be eradicated, even controlling their spread and proliferation can be expensive and extremely challenging.

The damage that alien (exotic) species can do to our delicate ecosystems varies depending on the species of concern and on the ecosystems into which they are introduced. Some can colonise in low numbers and coexist with minimal impact. Others can out-compete native species for habitat, food and resources, permanently altering the ecosystem for the worse.

In this Episode we talk to Dr Bonnie Holmes, Senior Biosecurity Officer with the Queensland Department of Agriculture and Fisheries. Bonnie is a pest fish expert and explains the level to which alien species currently impact on Wet Tropics Waterways. We also talk about what managers and the public can do to reduce the spread of alien species - and a handful of pest fish that DAF are working to prevent gaining a foothold in our waterways.