Water for the environment to preserve native fish population
A release of water for the environment into a drying reach of the upper Mt William Creek between Lake Fyans and Lake Lonsdale is helping keep a valuable native fish population going until the sky delivers its next burst of natural flows.
The release started this week and will run for seven days after Wimmera CMA requested that the Storage Manager GWMWater release 135 megalitres of the Victorian Environmental Water Holder’s environmental water allocation. The release is from Lake Fyans.
Wimmera CMA has been prioritising water for the environment in a section of the creek at Mokepilly since 2015 after scientific surveys identified it provided breeding and refuge habitat for native fish including southern pygmy perch, Australian Smelt, common galaxias and flatheaded gudgeon.
The Mokepilly pool is also free of carp which gives the native fish population a good chance of survival and dispersing into other parts of the creek when it’s flowing naturally.
Wimmera CMA chief executive David Brennan said there were very few refuge pools in the upper Mt William Creek, which made the Mokepilly refuge pool important for the long-term survival of the creek’s native fish population.
“We didn’t need water for the environment last year due to the wet spring and summer naturally maintaining suitable levels. But with limited rainfall so far this year the levels have dropped and the pool needs a top up to maintain habitat,” he said.
“This a small release which won’t noticeably affect water levels in Lake Fyans. It will, however, result in a significant positive impact for the refuge pool with longer-term benefits for the whole creek.”
The Mokepilly pool is part of an ongoing fish monitoring project that measures the effectiveness of managed releases. Previous monitoring results have shown releases of water for the environment have triggered breeding of native fish such as southern pygmy perch.
Lake Lonsdale Action Group member and Stawell Angling Club president Ray Howard said water for the environment was ‘vitally’ important for fishing.
“There’s a good population of fish in that Mokepilly area and when it doesn’t get enough natural inflows we need water for the environment to hold breeding stock and enhance this fishery into the future.”
Project Platypus manager Allistair Stephens said the local community had worked hard to highlight the importance of Mt William Creek, one of the biggest tributaries of the Wimmera River, for its role in the overall health of the broader catchment.
He said flows created by releasing water for the environment were one of several management actions that created benefits further downstream.
“Environmental flows are one of a range of important activities to maintain the health of waterways. We are also doing extensive work along the creek in partnership with landholders including controlling invasive species, maintaining and creating habitat through revegetation and slowing erosion and stopping deeper pools from filling up with silt.”
Project Platypus announced this month that it will target degraded private land next to Mt William Creek by planting more than 6000 native plants during this winter’s annual Plantout events.
“The reason we’re targeting this area is because there is an opportunity to recreate habitat for local species and to improve general ecology outcomes,” Mr Stephens said.
“It’s important all these activities come together as part of a holistic approach to waterway health, and refreshing the water in the important refuge pools for native fish using water for the environment is part of this.”