Seals, sometimes called sea dogs, are marine mammals related to dogs, bears and walruses.

ix species of seals are found along Canada's Atlantic coast. All have been hunted, but only two, harp and hood seals, have supported commercial harvests.

The principal commercial seal is the harp, so named because of a harp-shaped band of dark fur on the back and flanks of adults. Hood seals get their name from an inflatable protective sack, or hood, attached to the male's nose.

These seals migrate from the Arctic Ocean during the fall and winter, and gather in March and April on the ice floes off Newfoundland and in the Gulf of St. Lawrence to give birth and mate. The newborn pups, whitecoats, are fed on very rich milk and rapidly develop a thick fatty layer that can be rendered into oil.