From September to December, a research team from Australian Antarctic Programs will be deployed on the sub-Antarctic island at 53 degrees south to assess the health of animal populations.
Australia is bracing itself for the arrival of the highly pathogenic HPAI-H5 virus, which rarely affects humans, but often farms and wildlife. This time, the threat arrives via the Southern Ocean and the sub-Antarctic islands. After being detected in the South Atlantic, on South Georgia, it entered the Antarctic Treaty area in February 2024, causing waves of mortality in penguins, other bird species and seals. Last November, it was found in the southern Indian Ocean, on Crozet and Kerguelen, turning in the direction of the prevailing winds. 450 kilometers to the south of these archipelagos, no information is available on the first Australian islands of Heard and McDonald.
As the island is uninhabited, the Australian Antarctic Program will deploy a research team to Heard Island for a three-month period starting in September, to establish the health status of the penguins, albatrosses, cormorants and seals that inhabit the island. The research icebreaker Nuyina will make its first round trip in September, staying for around ten days. The logistics team will set up an initial camp, from which a circuit of the island will be established, complete with food and water caches.
“These caches will allow four people to live independently for three or four nights,” explains Senior Remote Area Operations Coordinator Marty Passingham in the release. “They will include sleeping tents, sleeping equipment, toilet tents, cooking equipment, food, some emergency supplies, power in the form of a 12-volt source, as well as a generator and means of communication.”
All equipment will be inspected and cleaned in advance to limit the risk of introducing exotic species to the island. Even the ship will undergo similar treatment. The three-month mission has been timed to coincide with the return of nesting birds and the reproduction of marine mammals such as elephant seals. On Kerguelen, the virus is believed to have arrived during this period, probably via healthy carrier birds. Seals then likely spread it.
As reported by Jérémy Tornos, a scientist at the Center for Functional and Evolutionary Ecology in Montpellier, it is still impossible to accurately estimate the impact of the virus on the island. The next summer campaign, which will be conducted in parallel with the one on Heard Island, will reveal the proportion of animals returning to the beaches during the breeding season.
On Heard, the first objective is therefore to find signs of the virus. “We will first use helicopters to get an overview of the island and assess the mortality of the largest species, such as elephant seals,” explains Dr. McInnes. Based on this initial aerial assessment, a second assessment will be carried out using drones to gather more detailed information. Next, hikers or sailors will travel to the island to collect biological samples from the animals. They will have to wear protective equipment to avoid becoming infected or spreading the disease.
The expedition is also one of the few times that Australia devotes to monitoring the island. It will therefore also be an opportunity to assess the state of the 12 main glaciers and to continue the inventory and count of animal colonies. “Heard Island is a stronghold for certain species; for example, it is estimated that there are over a million macaroni penguins,” explains ecologist Dr. McInnes. Weather conditions are likely to be rainy and windy, with temperatures close to 0°C, as is often the case at 53 degrees south.