Easier polar plunge for penguins

Abstract

Ecology In polar regions affected by a warming climate, it is increasingly important to understand what effect yearly variations in sea ice have on animal foraging and reproductive success. Watanabe et al. instrumented 175 Adelie penguins—a sentinel species for Southern Ocean ecosystems—with activity monitors and video cameras during four Antarctic field seasons with variable amounts of ice. During ice-free years, penguins traveled more by swimming rather than walking, lowering their energetic cost per unit distance traveled. Forage area increased in ice-free years, and more krill were captured per unit dive time, increasing foraging efficiency, growth rates, and breeding success. Adelie penguin populations in the continental Antarctic region are thus likely to grow in the coming decades as sea ice declines. Sci. Adv. 10.1126/sciadv.aba4828 (2020).