Mystery as 'thousands' of dead fish wash up along Aussie coast

A sad sight along the southeast coast of Australia stunned locals over the weekend with one admitting she'd "never seen anything like it" after noticing "thousands" of dead fish piled up and stretched along the beach.

The local woman was visiting Point Addis near Bells Beach in Victoria on Sunday when she came across the "dead or dying" fish lying lifelessly on the sand along the rock pools, while others said they too saw the same thing at other beaches along the coast.

"There's millions of them off the coast today. The water was thick with them diving this morning, and a massive school of them stretching the whole beach at Jan Juc Beach," another commented on the woman's social media post. Jan Juc is located south of Torquay, roughly 13 kilometres away from Bells.

'Stress' and 'low tide' likely to blame, locals suggest

The baffled woman asked if "anyone knows why" so many fish suddenly washed ashore with many suggesting a "combo of low tide, swells and warm water" is likely to blame. At first, the fish were thought to be garfish or sardines, but a handful said they're likely to be anchovies which are often targeted by bigger fish.

"I think it’s just a natural phenomenon. Tides, currents, low tides, warm temps just a bad combo for these lil fish," one explained. "Southern anchovies, I’d say they died from stress. These guys are tuna lollies and there is plenty of big schools of tuna in close at the moment," a second suggested.

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"This fish usually escapes from their predators and they mostly aim to go near sea shores on a high tide but since it was low tide they unfortunately didn't make their way back to the ocean, and the water dried out that's why they're dead," a third explained.

Experts chime in on ocean 'phenomenon'

According to Shane Roberts, general manager of aquaculture at the Department of Primary Industries and Regions (PIRSA), low tide and hot conditions have the potential to kill thousands. Anchovies, which often come into the shallows, can become caught in some of the gutters on very low tide, and on a hot day, the oxygen depletes quickly, he previously explained the the ABC.

Ian Tibbetts, Associate Professor at the University of Queensland, told Yahoo News Australia "this happens to bait fish all over the world".

"They look healthy apart from being dead," he said of the anchovies found washed up on Bells Beach on Sunday. "They move into the very shallow water to avoid predators – some get too close. If it was a low oxygen event, I’d expect to see a mix of species."

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