Around 9 a.m., ex-Navy SEAL Josh Jespersen summited the jagged, exposed 14,130-foot Capitol Peak. Having set out on a splitboard six hours earlier, Jespersen was tired, hungry, and ready to ride down.

But shrinking snow cover could threaten the seals' ability to make these icy lairs, researchers warn. The seals need at least 8 inches (20 centimeters) of snow cover to make their shelters.

Arctic-dwelling ringed seals build snow caves on top of sea ice so they can shield their pups from freezing temperatures and predators. But shrinking snow cover could threaten the seals' ability ...

Arctic-dwelling ringed seals build snow caves on top of sea ice so they can shield their pups from freezing temperatures and predators. But shrinking snow cover could threaten the seals' ability ...

Arctic-dwelling ringed seals build snow caves on top of sea ice so they can shield their pups from freezing temperatures and predators. But shrinking snow cover could threaten the seals' ability ...