Inland Waters

Aquatic Fauna

Freshwater fauna contribute significantly to Victoria’s biodiversity, and are integral components of freshwater ecosystems. Victoria is home to two species of freshwater mammals (the platypus and water rat), over 100 species of waterbirds, 33 species of amphibians, several reptiles, 46 species of freshwater fish and an undetermined number of invertebrate species.

Extraction of water, regulation of flow regimes and alteration of habitat are major pressures on aquatic fauna and a primary cause of decreasing native fish populations. Declining water availability over the past 11 years has also affected the fauna of inland waters.

Many species are now considered threatened, including 21 freshwater and estuarine fish species, 11 frog species and 29 species of waterbirds. Macro-invertebrate communities were found to be in good condition across almost half of the reach length assessed as part of the 2004 Index of Stream Condition. The total index of abundance for waterbirds in eastern Australia has shown a declining trend over past decades, with 2007 having the second-lowest abundance on record. Implications of the decline in the native aquatic fauna of inland waters include the reduced survival and diversity of species, and reduced ecosystem function and ecosystem services.

This section presents the current status of the aquatic fauna of inland waters. Ongoing threats to aquatic fauna are identified, and implications of the current status are discussed. This section also provides an overview of management responses and presents recommendations relating to the management of aquatic fauna in Victoria.

Part 4.3.5 - Aquatic Fauna (PDF - 2.1 MB)