Media release – Department of Natural Resources and Environment Tasmania, 16 October 2022
Macquarie Island’s annual elephant seal count underway
Tasmania Parks and Wildlife Service rangers and Australian Antarctic Division expeditioners are undertaking the annual seal count, spending up to four hours a day counting southern elephant seals (Mirounga leonina) on Macquarie Island.
Since the beginning of September, thousands of elephant seals have taken up temporary residence on many of Macquarie Island’s beaches, an important breeding habitat.
Located halfway between Australia and Antarctica, Macquarie Island, affectionately known as Macca, is a Nature Reserve and World Heritage Area that attracts around 80,000 elephant seals each year.
Southern elephant seals spend around eight months of the year at sea, returning to Macquarie Island to give birth, breed, and moult. Up to 18,000 breeding females, or cows, gather each year in groups called harems with their pups, and the large dominant males, known as bulls or beachmasters, keep busy by defending their harems from challengers.
Counting can be challenging, with some harems containing over 600 cows, resulting in a lot of commotion and movement.
This year, comparisons will be drawn between traditional counting methods to abundance estimates derived from aerial imagery, with more extensive elephant seal counts along other sections of the island’s 90 kilometres of coastline also undertaken.
Annual monitoring is used to estimate trends in abundance and has shown the island’s population is experiencing a slow decline, likely due in part to the foraging habitat of the population being impacted by changes to Antarctic sea ice extent due to climate change.
Understanding population size and trends is an important step in conservation for this endangered species, the largest of the world’s seals.
