Environment f low to keep fish alive

An environmental flow has started in the upper Mt William Creek between Lake Fyans and Lake Lonsdale to maintain an indigenous fish population in the waterway.

Wimmera Catchment Management Authority is releasing water for the environment into a section of the drying reach of the creek.

It is only the third time the authority has targeted this section of the creek, with previous releases in May 2015 and March 2016.

Wimmera CMA prioritised this section of the creek for environmental flows after scientific surveys identified it provided breeding and refuge habitat for native fish including southern pygmy perch, Australian Smelt, common galaxias and flatheaded gudgeon.

Wimmera CMA chief executive David Brennan said monitoring showed 2015 and 2016 environmental watering provided important boosts for native fish, including triggering breeding of southern pygmy perch.

He said with a wet 2016 the stream flow gauge at Mokepilly measured 35,022 megalitres of natural flows. In 2017 the gauge measured 3614 megalitres.

“But last year the creek only had 264 megalitres of natural flows and the most recent survey results indicate that it is under stress,” he said.

“Water levels have dropped significantly, salinity levels are increasing and this has impacted on native vegetation and native fish numbers.”

Lake Lonsdale Action Group member and Stawell Angling Club president Ray Howard said environmental watering was ‘vitally’ important.

“There’s a good population of fish in that Mokepilly area, but because it’s not getting any inflows and is on the verge of going dry, we need the environmental water to hold breeding stock and enhance this fishery into the future,” he said.

Mr Howard said it was important to keep rivers in good condition during dry times.

“It’s important to keep our rivers healthy so they can keep producing good fish,” he said.

“It’s good stretch of water which is very popular with land-based anglers because it has good access.”

Environmental researcher Dion Iervasi from Austral Research and Consulting said it was not unusual for the upper section of the Mt William Creek to become a series of isolated deep pools at this time of year, but circumstances were especially dry.

Researchers will return to the site for follow-up surveys to determine the benefits of the watering.