Fish migration triggered with enviro water

The Australian grayling has been known to migrate from the upper reaches of rivers more than 100km to the ocean as part of its life cycle.

As part of their migration Australian grayling swim through the Gippsland Lakes and into the ocean every year, before swimming back up one of the many rivers that flow into the Lakes from the Alpine regions.

This journey is helped along by environmental water or ‘freshes’. Environmental water is water that is specially allocated to be used for environmental purposes – refreshing pool and riffles, intermittently wetting bankside vegetation, encouraging fish migrations and connecting habitats to help achieve healthier rivers.

Freshwater flows from the Tambo, Nicholson, Mitchell, Avon, Macalister, Thomson and Latrobe rivers contribute to improving water quality, fringing vegetation, improving breeding opportunities for a range of fish and providing much needed habitat for native animals.

This year, the first Macalister River winter fresh will be released at the end of June from Lake Glenmaggie providing migration and spawning triggers for native migratory fish species (such as tupong and Australian bass), refreshing waterholes, and improving conditions for in-stream and fringing vegetation.

According to WGCMA Environmental Water Officer, Minna Tom, this winter fresh in the Macalister was based on the environmental flows study completed in 2015.

“This study found that winter freshes into the system had the capacity to boost the benefits of environmental water,” explained Minna.

“This complements other environmental watering this year, including the spring fresh released in the Thomson River last year for juvenile fish recruitment, the autumn freshes released in the Latrobe, Thomson and Macalister rivers earlier this year as well as the watering of the Heart Morass, one of the wetlands off the lower Latrobe River.”

For more information about environmental water, please visit www.wgcma.vic.gov.au