Mystery surrounds why hundreds of dead birds have washed up on Sydney's beaches - as experts say something is going 'drastically wrong' and declare a crisis

Corpses of short-tailed shearwaters have been spotted at several shorelines 

The birds are migrating back to southern Australia to breed but dying on way 

Krill and other fish they feed on have dwindled due to sea temperatures rising

By CHARLIE MOORE FOR DAILY MAIL AUSTRALIA

PUBLISHED: 04:09, 18 November 2019 | UPDATED: 12:08, 18 November 2019

Hundreds of dead birds are washing up on Sydney's iconic beaches.

The corpses of short-tailed shearwaters have been spotted at several shorelines including Bondi, Manly and Cronulla.

The birds are migrating back to southern Australia to breed after spending the summer in Alaska.

Hundreds of dead birds are washing up on Sydney's iconic beaches. Pictured: The corpses of short-tailed shearwaters on an Australian beach in October

But, according to experts, a higher number than usual are dying on the way due to a lack of food.

The birds need to be at full strength to make the 14,000km trip over the Pacific but the krill and other fish they feed on have apparently dwindled due to sea temperatures rising. 

Each year around 30,000 birds land at Griffiths Island at Port Fairy in Victoria but this time only half that number have made it, according to Peter Barrand, the president of BirdLife Warrnambool. 

Explaining why, he told Yahoo News: 'Water temperatures are rising, the fish shearwaters feed on are not coming into the shallows.

'There's certainly something that's going drastically wrong'.

The Short-tailed Shearwater is Australia's most numerous seabird. 

During breeding season, millions converge on many small islands from NSW to Western Australia, with their stronghold in Bass Strait. 

After their chicks are large enough to fend for themselves, the adults leave the breeding islands and migrate north-east, flying on a broad front through the central Pacific Ocean, where immense numbers were seen by Captain Cook. 

They spend the southern winter at sea in the northern Pacific, off Japan, Siberia and Alaska.

Source: BirdLife Australia 

BirdLife Australia has rendered the problem a 'crisis'.

In a statement on its website, the group says: 'For the fifth consecutive year, the sea surface temperatures off Alaska have been unusually warm, which has led to a dire shortage of the shearwaters' marine prey, resulting in thousands of dead shearwaters being washed ashore along Alaska's beaches. 

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