By Alistair Bates

Copyright abc

The mass deaths of toxic marine life off Western Australia’s Pilbara has prompted warnings from authorities.

In recent weeks, residents have discovered hundreds of dead puffer fish along Onslow Beach, more than 1,300 kilometres north of Perth.

The stretch of coast is popular with dog walkers, swimmers, and fishers from the nearby industrial town of Onslow.

Puffer fish are highly toxic to animals, and can cause severe illness or death if even a small quantity is ingested.

The Shire of Ashburton issued a public health notice on Wednesday, urging people to keep their pets leashed and report any further sightings for clean-up.

Onslow resident Sandi McAullay described the sight as a worry.

“The puffer fish, I’ve never seen before, and I’ve been on this beach … 60-odd years,” she said.

Ms McAullay said the dead fish had been washing up on the beach for much of September, raising concerns among dog owners.

“I would like to know why it’s happening,” she said.

“I really don’t want it to be the algae stuff that’s happened over in South Australia.”

Another resident Serena Maroney said she had counted almost 600 dead fish on the beach, and would not take the family dog for a walk until they were removed.

WA Department of Primary Industries and Regional Development (DPIRD) said it was looking into the puffer fish kill.

“DPIRD is working the Shire of Ashburton to investigate reports of several hundred dead puffer fish between Beadon Creek and Four Mile Creek,” a spokesperson said in a statement.

The department is yet to verify whether puffer fish are the only creatures affected.

The spokesperson noted the death of a single species would “almost certainly” rule out a pollution event or an algal bloom as the cause.

Jellyfish slam coast elsewhere

Puffer fish are not the only poisonous sea creature washing up on Pilbara shores.

Beachgoers near Port Hedland, Cape Lambert, and Dampier have been confronted by a minefield of Crambione mastigophora — or red-bell jellyfish — for weeks.

The bloom has swollen to such a size it has forced one tourism operator to temporarily close, and put the world’s largest port authority on alert.

Last week, Pilbara Ports issued a notice to its marine pilots flagging possible obstacles as they approached Port Hedland.

It said seawater intake by engine cooling systems and fire pumps could be clogged by the invertebrates.

“The engines have an automatic temperature gauge and once the temperature starts rising, it automatically starts slowing down the engine,” Pilbara Ports acting general manager Mike Minogue told ABC Kimberley-Pilbara Mornings.

“What we’ve had is a couple of instances where the vessels’ engines have slowed down.

More than $300 million in trade passes through Port Hedland each day, with even minor operational delays chalking up heavy losses.

Ship crews were also warned to avoid the jellyfish’s tentacles, the sting of which could be painful and lead to serious reactions like anaphylaxis.

Bloom good for turtles, but not business

In Dampier, tour operator Pilbara Dive has cancelled multiple outings because waters were too treacherous to enter.

Owner Natalie Callanan told ABC WA Statewide Drive the numbers were “triple” the amount typical for this time of year.

“There’s no way you’d be able to even walk in the water without them stinging you,” she said.

She credited the spectacle to a marine heatwave that smashed much of WA’s north late last year.

Surface sea temperatures broke records in the Pilbara and notched a new high globally.

The warming event caused coral bleaching along thousands of kilometres of WA reef systems, and the flow-on effects are still emerging.

Ms Callanan said it had created favourable breeding conditions for the jellyfish.

The real beneficiaries though are local sea turtles.

“The turtles love to eat these jellyfish, and with turtle-nesting season coming up, hopefully we’ll have a bumper one,” she said.