Harp Seals Dying as Ice Shrinks

Jan 4, 2012

Warmer temperatures in the North Atlantic over the last several decades have resulted in significantly higher mortality rates of baby harp seals. A new study out of Duke looked at satellite data of ice conditions in the Gulf of St Lawrence, a major breeding region and compared them to yearly reports of dead seal pups that washed up on shore. Lead researcher David Johnston is a scientist at the Duke University Marine Lab:

A harp seal pup on unstable ice in the Gulf of St. Lawrence Canada
Credit Stewart Cook/International Fund for Animal Welfare

David Johnston:  These animals have evolved to take advantage of the advan tages of ephemeral surfaces like ice.

And they have a very short lactation period. So they give birth to their pups and then 12 to 14 days later they wean them and leave. So you can imagine having a child... and then leaving them 12 to 14 days after. It's really a dramatic strategy for a mammal.

Johnson says the seal pups are left without protection before they learn to swim or hunt. That makes them particularly dependant on the ice during that period. Without the ice, the seal pups simply drown or fall prey to land-based predators. The seasonal ice cover in the region has been eroding by 6-percent each decade since satellite images became available in 1979.