Researchers are sounding the alarm over a possible mass marine mortality event.

Some sea dragon species could face the threat of becoming endangered due to a toxic algal bloom off Australia’s south coast that has been festering since March.

Marine ecologists David Booth and Gigi Beretta have been receiving hundreds of dead sea dragons in the mail, sent from concerned citizen scientists who collect the corpses washing up on the beach. 

The algal bloom has engulfed hundreds of kilometres of the coastline, turning pristine waters into a marine graveyard.

The silent killer has claimed the lives of around 34,000 sea creatures, including sharks, dolphins and stingrays. Thousands of sea dragons have died.

Experts are particularly worried about the delicate leafy sea dragon, which has leaf-style camouflage to help it hide in seaweed, and is only found in Australian waters. 

The South Australian government believes an ocean heatwave is the probable underlying cause of the algal bloom.

But while government funds have been allocated to tackle the effects of the crisis – no-one really knows how to stop it. 

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