Scientists on 'high alert' as bird flu threat looms over Antarctica

By Jano Gibson, for ABC News

At Berkley Island in East Antarctica, hordes of Adélie penguins are nesting on a rocky outcrop surrounded by broken sea ice.

As they waddle and squabble among themselves, Weddell seals slumber nearby, while a lone skua soars in the sky above.

It's a classic Antarctic scene, replicated across the continent's coastline.

But scientists are concerned about a threat looming on the horizon - the deadly H5 strain of bird flu.

"We know that this is a really contagious virus that can spread, but it can be absolutely dramatic and wipe out populations," bird ecologist Louise Emmerson said.

Over recent years, avian influenza has made its way across many parts of the world, causing mass mortality among mammals and birds, including Adélie penguins.

After ripping through South America, the virus reached the Antarctic Peninsula, on the western side of the icy continent, two years ago.

And two months ago, it was detected on the Australian external territory of Heard Island in the Southern Ocean, where hundreds of dead elephant seals were found.

But so far, there has been no trace of bird flu in the Australian Antarctic Territory, a vast region on the eastern side of the continent.

"We haven't found it in this area at this stage," said Dr Emmerson, who leads the Australian Antarctic Division's (AAD) seabird research team.

"But we're obviously very concerned about its arrival."

Scientists on 'high alert' for virus

Dr Emmerson's team has been on "high alert" for the past two years, knowing the virus could breach the Australian Antarctic Territory any day.

Before the scientists get too close to a colony, they launch a drone to inspect the penguins from the air to ensure there are no signs of bird flu, such as high rates of mortality.

Once they have the all-clear, they collect samples from bird droppings, which will be tested in a laboratory back in Australia.

They then set about gathering crucial population data, so they can understand the severity of the virus, if and when it reaches these shores.

"To detect an impact of any kind, you need baseline data," AAD wildlife ecologist Colin Southwell said.

"You need data on what was happening before, so you can compare what's happening after."

While Dr Southwell and Dr Emmerson have been monitoring colonies near Casey Station, other team members have been checking sites near Davis Station and Mawson Station.

"The area we work over is 4,000 kilometres in extent of coastline - that's the equivalent of eastern Australia to WA," Dr Southwell said.

"So it's a massive task to try and get to all of those islands and monitor every population."

Penguins face multiple threats

While the drones are useful for population checks, the team also has a network of about 50 nest-monitoring cameras located across eastern Antarctica.

The cameras take 10 photos per day during the summer breeding season, and one photo per week over winter, giving the scientists an accurate bird count for each site.

But bird flu is not the only threat for the penguins.

Climate change and industrial krill fishing also pose risks.

So, the scientists have been attaching tracking devices to some of the penguins to find out whether their feeding grounds are in the same area as krill-fishing vessels.

"With the population surveys, with the nest camera, observations with the tracking [devices], we're trying to get a baseline of what is normal in Adélie penguins," Dr Southwell said.

"So we can see whether there's been an impact from avian influenza or fisheries or climate change and all kinds of human impacts."

The ABC travelled to Antarctica with the support of the Australian Antarctic Program.

- ABC News