Collie River fish deaths update
Released 06 Feb 2015
The departments of Water, Fisheries and Health and the Shire of Collie are working together in response to recent fish deaths in the east branch of the Collie River about 7kms east-north east of Collie town site. Estimates are approximately 3000 freshwater cobbler, night fish, marron and redfin perch species died over a four day period from 30 January to 3 February 2015 in the eastern branch of the Collie River off Boys Home Road.
"We responded quickly to this report over the weekend where we gathered vital data for analysis, and follow up visits to the site this week have shown that fish have stopped dying," Department of Water South West region manager Adam Maskew said.
"Preliminary analysis suggests that dissolved oxygen was low at the site where the majority of dead fish and marron were found, and also in the upstream and downstream area.
"Low dissolved oxygen is a known stressor for fish.
"Results of algae sampling indicate no high concentrations of algae or potentially harmful algal species at levels that are likely to have contributed to the fish and marron deaths.
"However until other test data is available, including results of pathology tests being undertaken by the Department of Fisheries, we are unable to say what relationship the low dissolved oxygen had to the fish and marron deaths.
Pathology tests are currently being conducted by the Department of Fisheries Fish Health Unit.
The Department of Water is also analysing rainfall and streamflow data from the catchments of the Collie River east branch during this period.
Mr Maskew said the event was localised to a 3-4km stretch of the Collie River, and that signs warning the public not to fish or recreate in the affected area of the river had been put up by the Collie Shire. "Fish kill events can occur in response to a range of natural and other factors, and all possible causes are being considered due to the mixed use nature of the catchment," he said.
A statement will be released once all lines of investigation are complete.
Contact with dead fish found in the wild should be avoided and the Department of Health advises against eating or handling of fish found in these circumstances, or fishing or recreating in waterways during a fish kill or algal bloom event.
People are asked to report any fish deaths to the Department of Fisheries FishWatch on 1800 815 507.
Algal blooms should be reported to ALGALWATCH 08 6250 8064 (office hours).
Contact: Peter Collins
Phone: (08) 6364 6848 / 0434 603 441