Freshwater habitats occupy less than 1% of the Earth’s surface, yet they contribute disproportionately to global biodiversity. They support approximately 10% of all known species, and one third of all vertebrates. Unfortunately, they are also under the hammer with many freshwater habitats being degraded by a range of processes including exotic invasions, eutrophication, over extraction (of water) and flow regulation.
River catchments in South-east Queensland (SEQ) hold a special value when it comes to freshwater biodiversity in Australia.
They contain the highest level of richness and/or endemism of freshwater lungfish, gobies, catfish, rainbowfish, eels, bass, snails, damselflies, limpets, dragonflies, water striders, water beetles and backswimmers in Australia. The loss of 75% of the native vegetation in SEQ has caused significant changes in catchment hydrology and sediment delivery, resulting in declining water quality and loss of aquatic biodiversity.
SEQ is also Australia’s fastest growing metropolitan region. From 2006 to 2031 its population is expected to grow from 2.8 to
4.4 million people requiring an additional 754,000 additional dwellings. Predicted population increases in the region are likely to further impact on the ecological health of its waterways. Projected changes in climate will therefore act on freshwater ecosystems that are already under considerable stress and have reduced adaptive capacity. For these reasons, SEQ provides an excellent case study for understanding the consequences of global change on freshwater biodiversity and how we might conserve it.