Katrina BRANDON
ON National Fish Day last November (November 21), the West Gippsland Catchment Management Authority (CMA) released 10,000 Australian Bass, also known as Gippsland Perch, into Traralgon Creek to help revive the Latrobe River.
The river flows 260 kilometres, goes through the Latrobe Valley and meets Lake Wellington in East Sale. Latrobe River has had many names over the years, including its Gunaikurnai name, Durt’Yowan, nicknamed the Lurking River, due to damage throughout the years.
There are many reasons for the damage, according to Environmental Water Advisory crew member, Robert Caune, and Environmental Officer, Dr Adrian Clements. These include to carp and industry effects from mining, farming, and community use. Over the years, according to Dr Clements, there has been a 25 per cent reduction in water due to mining and other industries.
“Carp breed prolifically and strip everything out of the river – all of the food and vegetation. When all of that is gone, it starts regurgitating the mud, looking for bloodworms, undercutting banks, and creating murkiness in the water,” Mr Caune said.
The release is part of a state-wide native fish stocking program that aims to revive Victoria’s rivers. According to West Gippsland CMA’s documentary, released on November 14, more than 400,000 Australian Bass have been released into Gippsland waterways. The state government has invested in this program to improve waterway and catchment health across Victoria, including flagship waterway sites, investing $248 million into the revival.
“Our rivers are in such a bad state. They require a bit of stocking here and there, but it’s not the answer,” Dr Clements said.
“We can’t just go up to a river and stock it with whatever fish you like and expect them to survive. You need to provide them with the right conditions. You need to care for the vegetation, shelter, and plenty of food. Bass, in particular, eat a lot and pretty much anything.”
The West Gippsland CMA’s documentary explains the importance of keeping Latrobe River healthy, and its history dating back 200 years of how the river has been affected. The video also explains that keeping the river healthy gives better produce, more tourism, and better mental health.
Bringing in Australian Bass is one of the many ways CMA can help revive Gippsland waterways. Other ways are fencing up to 20 metres along the river to stop livestock; and taking out willows, replacing them with native species to help stabilise the banks. Having native plants on the banks will also provide a place for native fish to hide.
According to Dr Clements, Australian Bass also rely on springtime flooding for breeding as floods wash bugs and other foods into the water for the bass to feed off. The last big breeding event happened after the 2021 floods and was the first major one since 1985.
CMA has been working on getting waterways ready for the re-introduction of Australian Bass for more than 25 years, working on water quality and vegetation management. CMA also runs programs to help landholders know how to protect nearby streams. In the last 25 years, they have also pushed for understanding how to breed Australian Bass so that they could have healthy waterways again.
“CMA’s main role is typically in your rural environment, so we get farmers to manage nutrient runoff. The best thing you can do is visit the river more often, to know it, and do all the reading you can,” Dr Clements said.
According to Mr Caune, they use hydrographs to measure the river’s flow.
“It seems to have a pattern of having multiple little floods in springtime, and that is because of the very vital thing. These Bass need freshwater zooplankton and breed in salt water. So you have a flood coming against the salt wedge, and in this washing machine, hatched eggs are mixing in with these little things called zooplanktons, and at a density where they almost have to open their mouths, and it pops in,” he said.
Now, CMA wants people to get involved in rehabilitating the waterways in Gippsland and report things to authorities, such as local councils, if something isn’t right.
The Latrobe River is on the cusp of a significant change with the planned Latrobe Valley mine rehabilitation. The restoration threatens the water availability to the river, challenging the flow and disturbing the natural habitat. With the lack of floods and more water being used in mine rehabilitation, breeding the Australian Bass is a bit challenging.
“We are stocking the Bass because they need help. The river is missing some key flows that they need to breed but need a spring flood,” Dr Clements said.
According to Dr Clements, introducing Australian Bass to reduce carp is one of the most viable ways to control the carp population.
He said, “Australian Bass represents one of the most viable ways we can help control carp without using a virus. We get the bonus of returning a native fish, providing the local community with economy and utility. We also get to control the carp, which has ruined the river for many other uses.”
The fish have come from Narooma Aquaculture. Narooma Aquaculture breeds bass, dusky flathead, and estuary perch. On November 20, the crew drove up to Narooma and picked them up at 5am, journeying back to another waterway.
For more information on CMA, go to wgcma.vic.gov.au/ or youtube.com/watch?v=2JfhkTI264E for the documentary on the Latrobe River.
For more information on Narooma Aquaculture, go to narooma-aquaculture.com.au/Home.htm
