Penguins adapt to warm climate

Beaufort Island's Adelie penguin colony is thriving. Photo / Mark Mitchell
Beaufort Island's Adelie penguin colony is thriving. Photo / Mark Mitchell

A colony of Antarctic penguins could be excused for feeling like climate change's big winners.

A study has found a group of Adelie penguins on Beaufort Island in the Ross Sea, 3500km south of New Zealand, has boosted its numbers as nearby glaciers have receded.

A team of United States and New Zealand-based scientists has used aerial photographs from as far back as 1958 and modern satellite imagery to measure nesting areas and population.

"Population size varied with available habitat, and both increased rapidly since the mid-1980s," the team found. Numbers in the colony increased by 84 per cent as habitat grew by 71 per cent.

Between 1983-2010, habitat grew by 20 per cent as a snow-ice field near the colony retreated more than 500m. The researchers say their findings are different to what could be expected in other Adelie penguin habitats, where warm temperatures are causing population decline.

The team found average temperatures at the US's nearby McMurdo Station had increased by one degree Celsius between 1958 and 2010, most of it between 1980-2000.

They said temperatures in the October-December snow melt period had increased 3.2 degrees.

"Our results are in line with predictions that major ice shelves and glaciers will retreat rapidly elsewhere in the Antarctic," the researchers said in the journal PLOS ONE.

An increased prevalence of silverfish, which are eaten by the penguins, could also have contributed to the thriving population.

Fishing for Antarctic toothfish has reduced the competition for silverfish, meaning more food for the penguin colony.

- AAP

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