Freshwater fish

There 20 species of native freshwater fish found in the Adelaide Hills and Fleurieu region, including lampreys, eels, catfish, and galaxiids. Of these, three are considered threatened at the national level and another seven are considered threatened within this region. Unfortunately, another four species found within the area at the time of European colonisation have become regionally extinct.

Commonly sighted freshwater fish

The common jollytail can be found in many of the rivers and streams, highlighting the importance of looking after even our smallest creeks and streams in the region. Many of our native fish are small bodied, so don’t assume that just because there are none to be seen they’re not there!

Check out this native fish ID chart to see our most common native freshwater fish.

Threats

Some of the major threats to freshwater fish conservation are:

• climate change, drought and severe weather – including the threat of long-term climatic change which may be linked to global warming and other sever climatic/weather events e.g. droughts, temperature extremes, storms and flooding. This may increase the chance of summer water pools drying up, leading to the extinction of fish populations.
• water management and use – the regulation of rivers and diversion of water for urban supplies, industry and agricultural production have significantly altered flow regimes. Species requiring wet or moist conditions, and with narrow habitat requirements, will be most impacted by water management and use. Impacts will likely be more pronounced during dry seasons and extended drought periods where human use tends to exacerbate already low levels. Loss of summer water pools can lead to the extinction of fish populations as these act as a refuge for these species.
• predation and competition by introduced fish
• pollution and poisoning – pollution of waterways have been identified as a threat to water skinks. The general use of farming chemicals is considered to threaten some fish species.
• grazing and disturbance by stock – the increase in nutrients from manure may affect the quality of nearby surface waters.