Wildlife

Animals Are Shrinking and Freezing to Death in a Changing Arctic

Unusual weather brought by climate change is making it tough for muskoxen to get food—and sometimes even entombs them in ice.

Muskoxen, the plant-chomping, long-haired mammals that huddle on the Arctic tundra, are being born smaller in parts of the far north, as pregnant mothers struggle to find food.

One reason, according to new research published Thursday in Scientific Reports: Muskoxen eat most of the year by pawing through snow with their hooves. But rising temperatures mean precipitation increasingly falls as rain, only to then freeze on the surface, encasing plant life in inaccessible ice.

Meanwhile, in a type of freak weather event likely to become more common, more than 50 muskoxen died swamped in ice, as gusts of howling winds drove ice and freezing waters from a tidal surge so far inland that fish were found a half-mile from shore. Rising seas are making such surges bigger and more common.

During one February flight in 2011, one of Berger's co-authors was in a plane, photographing 55 muskoxen standing in a lagoon. A couple of weeks later, 52 of them were dead, most almost completely buried in ice. One animal had chunks of ice in its throat. The only animal not completely encased was standing and appeared to have been trying to walk.

By piecing together weather anomalies, Berger and crew figured out the most likely scenario: the animals had fallen victim to an odd type of localized tsunami. High winds pushed average tides near the site 16 times higher than normal, propelling thick ice and waves inland. Five-meter-long plates of ice up to 50 centimeters thick were found piled near the muskoxen.