Monitoring bird and seal colonies in Antarctica has taken on a new urgency with the detection of the highly pathogenic Avian Influenza on the continent for the first time. The Council of Managers of National Antarctic Programs (COMNAP) has confirmed that two dead skuas found near the Argentinian Primavera station on the Antarctic Peninsula tested positive to the virus in late February.

There were always fears Avian Influenza would reach Antarctica this season but seabird ecologist Dr Louise Emmerson said it was a shock nonetheless.

“It has had a devastating effect in nearby South America,” she said.

“Tens of millions of birds have died globally and there is evidence that it also had a dramatic impact on southern elephant seals and fur seals.

“Some individuals within populations seem to be coming through it OK but there have been some weird and unexpected outcomes for some species. The northern gannet, for example, usually has blue eyes but when they recover from Avian Influenza, their eyes are black and we are not sure why.”

What’s more, Dr Emmerson said no-one knew what the impact of that adaptation would be.

“Could the black-eyed gannets have a breeding disadvantage? And did their blue eyes help with their foraging? There’s so much we don’t know about how species will respond and we need more research to resolve this.”

Cruise ships adopt new biosecurity measures

Dr Emmerson spent some of the summer monitoring bird colonies for the virus from a cruise ship on the Antarctic Peninsula with a colleague from Oxford University in the UK.

Dr Emmerson and her colleague, Dr Tom Hart, would join the expedition team on a zodiac and head out on a scouting trip to a penguin colony.

They would visually scout for signs of the disease and go ashore first, to conduct drone surveys of the penguin colonies and check the site was clear for passengers.

At the time, there were no signs of the mass deaths or neurological symptoms characteristic of the disease, but biosecurity measures on cruise ships had been ramped up in response to the risk.

“Before passengers came down to get on a small boat to visit a penguin colony they’d take their hiking boots and poles and their backpacks and camera bags – anything they were going to take into the field, and they’d disinfect them.

“The cruise ship provided rubber boots for everyone to walk in, and an outer layer with a hood and walking poles for people to use so we could make sure everything was clean.

“Then when we got back, everyone would scrub their boots and poles and make sure everything that had touched the ground was disinfected.

“This year, we didn’t allow people to sit on the ground or put their packs on the ground. But the passengers were great about it, they took the risk to the wildlife and themselves very seriously.”

“The species we were always most worried about was skuas”

Some colonies along the Peninsula had been closed to visitors while suspect deaths were investigated but none were confirmed as Avian Influenza.

However by then, the virus was confirmed on South Georgia and the Falkland Islands.

“The species we were always most worried about was skuas because they’re scavengers and they undertake considerable winter migrations. For example, the skuas from East Antarctica fly all the way up to Japan, Korea and China so the chance of them being exposed to the disease was always greater.  Penguins that breed in Antarctica don’t go very far north in winter so if they get it, it will be from other wildlife, including the northerly migrating seabirds, or humans.”

Camera network vital for monitoring

As part of the summer monitoring project, Dr Emmerson and Dr Hart also maintained and downloaded data from Dr Hart’s camera network, set up along the Antarctic Peninsula to monitor nesting sites.

The network is based on an idea pioneered in Hobart by Australian Antarctic Division engineers in the early 2000s. 

The AAD’s network has about 44 cameras set up at key locations along the East Antarctic coastline, taking ten photos a day of about 30 to 40 nests per camera.

Species monitored include surface nesters like Adelie penguins, cape petrels, fulmars, southern giant petrels and emperor penguins.

“The cameras are on tripods and they’re very robust,” Dr Emmerson said.

“We can use the images to monitor when the birds arrive and leave, the timing of chick creche and their breeding success.

“The photos are stored on a camera card, so we still need to physically go and retrieve it, but that’s because we went for the simplest model possible. If it was downloading to a satellite there would be a requirement for more battery life and there would be issues and financial costs with bandwidth in transferring the images.

“The cameras only focus on a small part of the population so we still need to get there physically to attach foraging trackers and collect samples.  It doesn’t replace our field work but it does complement it and allows us to expand the spatial coverage of our monitoring.”

Dr Hart’s network includes about 100 cameras placed along the Antarctic Peninsula and unlike the AAD’s, relies on artificial intelligence to process the images.

Networks like these are now critical to track the incursion of Avian Influenza and planning is underway to check some of the more remote parts of the AAD network near Davis research station before the end of the research season.

The AAD will also revisit its bird flu management protocols.

“We need to make sure all our expeditioners know what their responsibilities are and where the disinfectant is and what to do if there are signs of the virus,” Dr Emmerson said.

“We can’t stop it spreading through the natural migratory process, but we can stop ourselves moving it around and that’s what we need to focus on.”

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