Each spring about 20m shearwaters fly 15,000km to Australia from the northern hemisphere. This year, beachgoers have been finding many emaciated carcasses

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Thousands of short-tailed shearwaters are washing up dead on Australian east coast beaches and researchers are uncertain of the cause and scale of these seabird “wrecks”.

Each spring about 20m shearwaters, also called yula or muttonbirds, fly 15,000km back to southern Australia from the northern hemisphere. Since late October, dead shearwaters have been turning up on beaches in south-east Queensland, followed by similar reports in New South Wales and Victoria in recent weeks.

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