Researchers have discovered a spike in Wimmera native fish numbers including a rapid spread of the previously declining Southern Pygmy Perch (pictured above) from the Grampians all the way to Horsham.

Wet conditions during the past two years, combined with regular environmental flows, have boosted fish numbers and allowed them to repopulate areas impacted by years of drought.

Researchers also discovered several River Blackfish as well as Flat-headed Gudgeon in the MacKenzie River downstream of the national park, the first recording of the species at this location for several years.

Fish ecologists from DELWP's Arthur Rylah Institute made the discoveries during surveys for the Victorian Environmental Flow Monitoring and Assessment Program (VEFMAP).


Pictured above: Arthur Rylah Institute fish ecologist Joanne Sharley and Scott Raymond during their surveys of MacKenzie River and Burnt Creek. Photo contributed.

Wimmera CMA chief executive David Brennan says the results reinforce the positive outcomes good flows and habitat can achieve.

"People who have lived along these waterways for decades speak fondly of the fish populations and thanks to water for the environment and improved seasonal conditions, we are seeing fish species return. The community will be particularly excited about the Blackfish discovery," Mr Brennan said.

"We are seeing significant environmental gains in both these systems. Over the past couple of years we have seen the Peron's Tree Frog populating the entire Burnt Creek system and now we are starting to see the fish make their way along the Burnt Creek and MacKenzie River.

"Over the years, drought conditions and other demands for water meant these waterways used to only receive a fraction of the water they needed to support vibrant and diverse fish populations. We are very excited about these results and they indicate that waterway health in the region has turned a corner."

Mr Brennan said that having the Arthur Rylah Institute undertake research in the region was vital in gaining a better understanding of the impact of environmental flows.

"It also helps us improve timing and delivery of these flows to achieve the best results," he said.

Fish ecologist Joanne Sharley from the Arthur Rylah Institute says there are a number of exciting findings showing the condition of these waterways is continuing on the right trajectory.

"The most pleasing outcomes are related to Southern Pygmy Perch, a small-bodied species in decline across much of their natural range in Australia," Joanne said.

"This species accounted for most of the fish caught. The monitoring shows they are successfully breeding in both the MacKenzie River and Burnt Creek and extending their range. Their greatest numbers were found to be where aquatic plants were abundant, highlighting the value of habitat for these fish to breed and avoid predators."

  • Environmental water releases in the MacKenzie River and Burnt Creek are prioritised as part of the Victorian Environmental Water Holder's (VEWH) Seasonal Watering Plan 2017-18, which aims to improve river and wetland health across the state.
  • Wimmera CMA has released its planned flows for summer online at www.wcma.vic.gov.au which it adjusts depending on weather conditions.
  • VEFMAP is funded through the Victorian Government's $222 million investment in waterway and catchment health over the next four years.