A famous Australian seabird is making its annual return to the country, but beachgoers have noticed something strange this year.
Thousands of short-tailed shearwaters, also known as sheepbirds, are found dead on Australia’s east coast.
Lauren Roman, a researcher at the Institute of Marine and Antarctic Studies, said the mass deaths were first reported in New South Wales last week and in Tasmania a few days ago.
Dr Roman said dead birds had been spotted on some beaches in central and southern New South Wales and south-east Tasmania.
“This mortality event is moving south, in my opinion, with the southward migration of late arrivals,” she told ABC Radio Hobart.
Dr Roman said studies showed sheepbirds tended to arrive from the northern hemisphere between late September and mid-November, with most birds arriving in October.
Known as “seabird wrecks”, Dr Roman said these mass die-offs had been occurring on rare occasions for a long time – always at this time of year.
“We have records going back to the 1800s,” she said.
“One of the most alarming things for researchers is that over the past few decades, these large mortality events have been occurring more and more often.”
Dr. Roman said it was “too early to know” what caused the wreck.
“We know they are adults, have recently completed their migration and are hungry,” she said.
The birds only have one chick per year, Dr. Roman said, so it may take some time for the population to recover from the wreckage.
Dr Roman said people should not touch birds if they were sick, saying it was a question of “when and not if” bird flu came to Australia.
“There is a chance, a small but real probability, that these birds have been in contact with this disease,” she said.
Bird deaths appear to be ‘food-related’, says ecologist
Seabird ecologist Jennifer Lavers said she had received reports of sheepbird deaths from the Gold Coast in Queensland to Bruny Island in southern Tasmania.
“It’s quite prevalent at the moment,” she told ABC Radio Hobart.
“At the moment it is 99% one main species: the Tasmanian short-tailed shearwater, or muttonbird. But it is possible that this will change over time.”
Dr Lavers disputed the theory of some other experts that the mass die-offs were associated with the recent migration of birds.
“One would expect some mortality associated with this, but their migration ended over six weeks ago,” she said.
From the information she had gathered, she said it appeared the deaths were due to food shortages due to warming oceans near Australia.
“Almost all of the stranded birds were very emaciated,” she said.
“It takes several weeks, not a few days, and that really reassures us that this is a food-related marine conditions issue.”
Dr Lavers said almost 1,000 short-tailed shearwaters had been tested for bird flu and all were negative.
But she said people should not touch birds without personal protective equipment – or let their dogs near them – because disease could not be ruled out.
“There is no sign at this stage that bird flu has reached Australia, but we just want to be careful,” she said.
Public urged to report dead seabirds
Dr Lavers said the public could help trace short-tailed shearwater mortality by sending messages reports of dead birds at Adrift Laba research group that she coordinates.
She said useful information included photos of the bird to confirm the species, where it was found, the date and the number of dead birds seen in a particular area.
Dr Roman said sick, injured or dead wildlife could be reported to Wildlife health in Australia.