Freshwater Guardian - Freshwater fishing news from the Department of Fisheries, Western Australia
Issue No. 8, August 2016

A terrible twin – the indistinct river shrimp

The tiny, transparent indistinct river shrimp closely resembles the native glass shrimp

If you went dip netting in the freshwater streams of the South West, you would more than likely scoop up a small transparent shrimp. The glass shrimp, Palaemonetes australis, is native to Western Australia and grows no bigger than 5 cm. 

Until 2013, this native shrimp inhabited our freshwater systems and estuaries without any serious competition. Then another, almost identical shrimp species was detected. More.

Hairy marron slow to romance

Juvenile hairy marron are held in breeding ponds

As the critically endangered hairy marron is now found only in three pools in the Margaret River, a captive breeding program was started with the goal of releasing them to boost wild populations.

However, breeding the hairy marron is proving to be a challenge. More.


The real toll of illegal traps

fish traps left in waterways drown wildlife such as the rakali

The illegal use of traps in our river systems, like the opera house trap pictured, poses an onging threat to our native wildlife. Mammals, reptiles and birds entering traps are unable to escape and quickly drown.

A recent community survey reported that the deaths of rakali, the Australian native water rat found in the South West, was mainly caused by drowning in illegal traps. More.

Barcoding for quick identification

Colourful DNA barcodes can confirm species identity.

Until recently, species were identified using features like the shape, size and colour of body parts. But decisions based on looks alone can be a tedious process and requires specialist expertise.

That’s where DNA barcoding (pictured) can be a handy tool, allowing quick identification of pest species. More.

Image credit: Rakali and trap photo by Paul Mutton.