Less Sea Ice Means Better Eating, Breeding for Antarctic Penguins

Adélie penguins in Lützow-Holm Bay, Antarctica, enjoy easy access to food and increase body weight and breeding success in ice-free summer. (Yuuki Watanabe / National Institute of Polar Research, Japan)

(CN) — Ever the resourceful animal, Adélie penguins in eastern Antarctica made the best of a bad situation about three years ago during a warmer breeding season when there was less ice in their environment: they ate more food.

The penguins also had much more success in finding breeding partners according to a study published Wednesday in the journal Science Advances.

Climate change has drastically altered the Antarctic sea ice and the problem will only be exacerbated over the next century. Still, this species could be the rare winner in a steadily warming planet, according to the study authors.

The species of penguin were able to travel farther because they were no longer land locked and were able to get to larger foraging area according to the research team lead by Yuuki Watanabe with Japan’s National Institute of Polar Research (JNIPR).

With shorter trips, more food and lower energy spent on their travel, the population of penguins saw greater body mass, chick growth rates and more breeding, according to the researchers.

Previous studies showed Adélie penguins did poorly in years with greater sea-ice growth and better in warmer breeding seasons.

The JNIPR team tagged 175 penguins with GPS devices and other equipment that tracked their movement and how much food they were able to catch.

Since the penguins did not need to find cracks in the ice to catch their breath, they didn’t have to dive as much and more krill was captured each time, which could also be connected with phytoplankton blooms in the sunlit ice-free water between the study window, the researchers said.

“Variable breeding success within the three ice-covered seasons also stresses that the presence or absence of sea ice is not the only factor determining penguin foraging conditions or breeding success,” they wrote.

The higher number of nests recorded during the breeding season were recorded in the ice-covered season rather than an ice-free season, so the results somewhat varied.

“It turns out that these penguins are happier with less sea-ice,” said Watanabe in a statement. “This may seem counterintuitive, but the underlying mechanism is actually quite simple.”

This added benefit only applies to penguins living on continental Antarctica, as those that live on the peninsula favor the colder breeding season.

“The general image may be that animals in polar regions suffer from ongoing climate warming. But our study shows that the completely opposite case can happen and highlights the complexity of climate change effects on wildlife,” Watanabe said in an email.

The study authors have their theories on why one population values a warmer season while the other doesn’t and this will be the focus of future studies.

%d bloggers like this: