Good news for Swan and Canning fishers and crabbers – no toxic Alexandrium algae detected in latest sampling

In some welcome news for the thousands of Perth fishers and crabbers who love to fish the Swan and Canning rivers, latest State Government water quality monitoring detected a zero presence of toxic Alexandrium algae.

Reports of zero presence of toxic Alexandrium algae in the Swan and Canning rivers is great for blue swimmer crab fanatics.

A recent Department of Biodiversity, Conservation and Attractions (DBCA) Alexandrium stakeholder update said: “Overall, since early December we appear to be experiencing a start-stop situation, which may be being influenced by the strong easterly winds causing mixing and prohibiting Alexandrium getting a strong foothold”.

Blooms of the algae effectively shut down large sections of the estuarine system to fishing for the past two summers and Recfishwest Policy Manager Leyland Campbell welcomed this latest set of water sampling results.

“It’s an ill wind that blows no one any good and even though strong Easterlies might not be the greatest for fishing generally – if it stops Alexandrium spreading through the river this summer – then that’s no bad thing,” he said.

“The Swan-Canning river system is one of the most important recreational fisheries in WA – particularly as one of WA’s primary crab fisheries.

“So, clearly, this is great news for the legions of recfishers out there who like to eat crabs and fish from the river.”

However, caution is still being urged this summer in the event of another bloom of the algae which can cause paralytic shellfish poisoning (PSP) if consumed in the head, guts and gills of crabs and in shellfish like mussels.

Swan-Canning crabbers still urged to clean their crabs

Subsequently fishers urged are still being urged to clean their crabs prior to freezing, cooking and eating their crabs and not eating mussels from the rivers.

Read the Department of Primary Industries and Regional Development’s pamphlet on how to clean your crabs here

As we reported in November, the Departments of Health (DoH), Biodiversity, Conservation and Attractions (DBCA) and Primary Industries and regional Development (DPIRD) changed their approach to managing the risk of people fishing in the Swan and Canning contracting PSP by consuming crabs from the system.

The agencies advised recfishing could now remain open for blue swimmer crabs throughout the crabbing season (1 December to 1 September) and year-round for fish throughout the Swan and Canning, but issued the precautionary advice around cleaning crabs.

A change in approach by State Government

The change of advice came after Paralytic Shellfish Toxins caused by Alexandrium were only found in the guts and gills of crabs and not the meat from extensive samples and testing of Swan-Canning river crabs by DoH.

It was anticipated that sizeable Alexandrium blooms would reoccur again this summer, however, “Alexandrium was not detected at any routine water quality monitoring sites in the Swan and Canning”, in the latest sampling.

“It’s important fishers still continue to follow the advice and exercise caution and remove the mustard and the dead man’s fingers from crabs prior to freezing, cooking or eating them,” Leyland said.

“We will continue to ensure full fishing access to the river system is maintained even if Alexandrium returns in significant levels.”

These signs have been placed around the Swan and Canning rivers to caution fishers.