Mallacoota fish kill a natural occurence

08 August 2018

The minor fish kill currently impacting Mallacoota’s lower lake is likely a natural occurrence caused by environmental conditions in the inlet, which has been closed since November last year.

Victorian Fisheries Authority (VFA) CEO Travis Dowling said sand whiting were most affected although numbers of dead fish were low and varied day to day depending on prevailing weather.

“Long-time locals suggest bream and luderick may also be vulnerable, but there are no signs of those species being affected currently,” Mr Dowling said.

“Marine species like sand whiting are more susceptible to low oxygen levels, elevated salinity and cool water temperatures of a closed inlet, unlike estuarine species that have evolved to better cope with such conditions.”

“Affected fish may show symptoms including red spots or ulcers on their skin and reddening of their gills. Some schools of whiting have been observed behaving unusually in the shallows.

“We are urging recreational anglers not to eat dead or dying fish, or use them as bait.

Mr Dowling said liaison with other natural resource agencies such as the East Gippsland Catchment Management Authority, the Environment Protection Agency and Parks Victoria suggested opening the inlet’s entrance would not help the situation and could make things worse.

“The estuary needs to open naturally following good rain, which will flush the entire system. Opening the estuary at its current low water level risks losing the top layer of more oxygenated water and leaving the cooler water behind.”

Mr Dowling said the VFA had sent dead fish away for testing and would continue to do so if more species became affected.

“We have Fisheries Officers monitoring the situation, talking to people on the ground about what they’re seeing and keeping the broader community informed about the latest happenings.”