Redfin in new waters

Redfin perch
NSW DPI Fisheries technician Stuart Watters holding a redfin at Blowering Dam in 2006.

Fish researchers are investigating whether populations of redfin perch in the Wollondilly catchment are carrying a virus that can devastate popular angling fish such as Murray cod, native perch species and trout.

NSW Department of Primary Industries’ freshwater fish scientific officer, Jamie Knight said Department and University of Sydney scientists were testing for Epizootic Haematopoietic Necrosis (EHN) Virus.

"The biology and spread of redfin is also being investigated," he said.

Currently 22 sites including Wollondilly are being surveyed and tested.

This follows discovery of the fish at new sites in the upper Lachlan, Abercrombie and Wollondilly river catchments in the central ranges.

These new populations of the feral fish could also cause havoc for native threatened species of Macquarie perch and southern pygmy perch.

"Redfin are aggressive, voracious predators, eating small fish and the juveniles of large native fish," manager of DPI’s aquatic biosecurity team, Jane Frances, said.

"They can also degrade recreational fisheries, building up large numbers and crowding habitats.

"This leads to stunted fish which are poor eating."

Redfin were introduced from Europe in the late 19th century for angling.

They are also known as European perch, redfin perch, English perch and Eurasian perch.

NSW DPI has received $83,000 funding from the Hawkesbury-Nepean Catchment Management Authority to explore options for excluding redfin perch from habitats supporting threatened Macquarie perch above Warragamba Dam.

DPI has distributed posters on the feral fish to licence agents around NSW to help raise awareness among anglers.

Some simple and effective ways to protect waterways and stop the spread of the redfin:

  • Don’t transfer fish between waterways or into farm dams
  • Don’t use live fin fish as bait in freshwater
  • Obtain a permit to stock fish
  • Don’t return pest fish to the water - kill it humanely and dispose appropriately.