More than half of the freshwater fishes in the Murray-Darling Basin are small-bodied (growing less than 15cm long). These small-bodied freshwater fishes typically possess traits that make them vulnerable to environmental change, such as being short-lived, having limited dispersal abilites and occupying small home ranges. Not surprisingly, many have declined across the Basin, and some are at risk of extinction. The Lower Murray, a hotspot for 80% of the Basin’s small-bodied freshwater fishes, provides a prime example as already threatened species were impacted by critical water shortages (2007 to 2010) during the millennium drought.
So how do we attempt to ensure the long-term future of these species?
Firstly, acknowledge that, whilst critical to the persistence of some species, previous recovery measures have not matched the scale of the problem. Next, accept that translocations of considerable numbers of fish over extended periods (i.e. more fish, more often) are a necessary prerequisite to create a network of self-sustaining populations to combat fragmentation and localised impacts, which need to be supported with complimentary restoration (flows, habitat and alien species). Lastly, concede its now or never for some threatened small-bodied freshwater fishes (think Yarra Pygmy Perch). Simple right?