Learn About Weddell Seals And Grey Seal

One of the more commonly sighted seals, Weddells often are found in groups. Some of these groups contain several hundred seals, although this typically occurs during their breeding season (September to November). During this time, males engage in numerous territorial battles. Unlike other species, these seals prefer to lie on snow and ice even when open land or rock is available. This trait, along with their desire to avoid Orcas, is one of the primary reasons Weddells are found on inland fast ice around the continent. During the winter months, Weddells must maintain diving/breathing holes in the ice in order to feed. Feeding primarily on fish, Weddells can dive in excess of 1,000 feet (300 meters) in search of food. To make these long dives possible, they carry five time the amount of oxygen in their blood as human do. To get the most from this, Weddells slow their heart rate and limit blood circulation to vital organs such as the brain, kidneys, and liver.

These large seals inhabit remote islands and shoals on both sides of the northern Atlantic. In North America most live along the Canadian Maritime provinces, although smaller numbers are found along the shores of New England. Their distinctive long nose has earned them the name of "horsehead." Their scientific name means "hook-nosed pig of the sea." Grey seals have color patterns that are similar to, but bolder than those of harbor seals.

Grey seals are sexually dimorphic in size. Males grow to 8 feet and weigh about 800 pounds, while females are smaller, growing to 7 feet and weighing about 400 pounds. Female grey seals are estimated to live to at least their mid 30's. Males are estimated to reach only their mid 20's, which may be a result of the fierce competition between males for mating rights with the females. The mating system for grey seals is polygynous (poly = many; gyny = female), in which males mate with many different females. Mating occurs on land and at sea. The nearest grey seal pupping area is in Nantucket Sound, on Muskeget Island, west of Nantucket Island.

Breeding takes place on rocky or sandy islands or land fast ice after pups are weaned. Newborn pups averaging 3 feet and weighing about 35 pounds are born in January and February. Pups are born with a creamy white coat called lanugo ( a reminder of their ancestral association with ice), which is shed shortly before the mother leaves them at about 3 weeks of age. Unlike the harbor seal, grey seal pups are rather helpless, staying on land in the birth area while the mother attends to them. The mother will leave the pup to feed, and upon return will recognize her offspring by its unique smell. Mothers are fiercely protective of their young.