Predictions of less snow may be bad news for ringed seals

Using  environmental conditions projected for ringed seals (Pusa hispida) in the Arctic, researchers found there may be less snow, which can spell bad news for the species.

The seals rely on snow drifts to create lairs as protection against cold and predators.  Anecdotal evidence suggests a lack of snow can be devastating for them.

“There have been pretty fascinating accounts of widespread pup mortality,” said Jody Reimer, a PhD candidate at the University of Alberta and lead author of the study published in Ecological Applications. Even without climate change necessarily playing a role, she said, in past years with low snowpack or rains that washed away the snow, “nearly all of the pups got snatched up by predators right away.”

In the study, Reimer and her colleagues created a model combining survival and reproduction rates for ring seal populations in Amundsen Gulf and Prince Albert Sound in Canada with ice and snow forecasts.

“Especially with climate change, there are emerging factors we think will be a problem down the road but it’s too early to get a good data set,” Reimer said. “We took all the existing literature and synthesized it into the best existing hypothesis.”

The team found decreasing snow is likely going to impact pup survival more than early ice breakup. A couple years of low snow wouldn’t affect pup survival much, Reimer said, but by the end of the century, ringed seals, which need 20 to 30 centimeters of snow to create their snow lairs for pupping, could decline from 50 to 99 percent because of decreasing snow.

This can have effects on the larger ecosystem, she said. “Ringed seals are the primary prey for polar bears,” she said, which are also expected to be impacted by breaking ice. “If you know about numbers for one, you can guess the other.”

Reimer said she hopes to continue building the model with more data.

“Some people say if you don’t have information, you shouldn’t be building a model,” she said. “But this type of model is a good tool when you don’t have a ton of data.”