Adult male hooded seals average 9 feet and weigh up to 900 pounds. Females are somewhat smaller, reaching lengths of 7.5 feet and often weighing more than 600 pounds. Adult hooded seals have a distinctive bluish-gray coat spattered with dark, irregular spots. The face is black, with a broad, flattened muzzle, and their large eyes are positioned near the top of the head. Males have a hood-like structure on top of the muzzle which can be inflated to form a crest nearly twice the size of a football during courting and territorial displays.
Males can also inflate their nasal septum and blow it out through the nose like a red balloon.
Hooded seals are powerful swimmers but they are unable to walk on land. Instead, they use a wriggling motion to move on their bellies when on shore. Like all true seals, they have a thick layer of blubber beneath their skin which provides insulation, reserve energy and buoyancy. Hooded seals feed on redfish, Greenland halibut, squid, herring, octopus, capelin, arctic cod, shrimp and mussels, among other things. Hooded seals are common to eastern Canadian arctic and subarctic waters, but wandering individuals have been spotted as far south as Puerto Rico.