Harbour Seal (Phoca vitulina)

After days of driving I was beginning to think I wouldn’t have anything decent to blog about. Between Montreal and Halifax the only wild things I saw were city birds, roadkill, and some deer. I was hoping to see a moose (and since we had to drive for an hour in the dark outside Fredericton, I thought it was pretty likely), but that didn’t happen. I had resigned myself to blogging about deer, which I do like, but they are pretty run-of-the-mill animals. Yesterday, however, while sitting on a Halifax pier, bathing in the afternoon sun and listening to the soothing sound of seabirds and lapping waves, I spotted a seal!

We watched him swim around for a while, popping his little head up in a different spot every five minutes or so. He actually came up quite close to the docks, maybe 50 feet away from us. I’ve seen seals in the Vancouver harbour, but it was such a beautiful day and seeing the seal in Halifax just made it all the more special. Plus, now I have something to write about!

A harbour seal's face. His big eyes have a flattened cornea to allow him to see in dark waters, and his whiskers are extra sensitive to detect acoustic waves made by prey in the water.

A harbour seal’s face. His big eyes have a flattened cornea to allow him to see in dark waters, and his whiskers are extra sensitive to detect acoustic waves made by prey in the water.

Harbour seals are very common seals, and in fact have the largest range of any pinniped (which includes eared seals, true seals and walruses). They pretty much live all around the northern coast of North America, and on the eastern coast of Asia. As their name implies, harbour seals prefer coastal waters, and are often seen by harbours or beaches, rarely venturing into deep open ocean waters.

Seals spend a fair bit of time in the water; and all that swimming gets pretty tiring. To rest, seals have haul out sites, which are beaches or rocky coastal areas where they can get out of the water and sunbathe. Hauling out doesn’t just give the seals a place to sleep – it also gives seals a respite from predators, helps maintain an ideal body temperature, and provides a place for females to give birth. Hauling out increases during moulting season, when the seal’s fur dies off and a new coat is grown.

Though harbour seals look silly and uncomfortable on land, they are graceful and well adapted to life in the water. Their hind limbs are ideal propellers which can move seals through the water at incredible speeds. Their noses are extremely narrow, and they shut these while swimming to prevent water from entering the nostrils. While diving, harbour seals stop breathing and slow down their heart rate, which lowers oxygen consumption and allows the seal to stay underwater up to 40 minutes. These aquatic adaptations allow harbour seals to successfully hunt for their main food, fish.

A baby harbour seal. Unlike many other phocids, harbour seals quickly lose their fluffy baby coat, so they can adapt to sea life faster.

A baby harbour seal. Unlike many other phocids, harbour seals quickly lose their fluffy baby coat, so they can adapt to sea life faster.

Seals mate in the water, which, though exciting, means it’s very difficult for people to observe this behaviour. So we don’t really know much about it. What we do know is that gestation is about 10 months, and females give birth on or very close to land, to avoid predators. There is a specific season in which harbour seals give birth, from late winter to summer. The baby seals quickly bond with their mothers, through yelps and barks, to allow the mamma seal to recognize her pup. The mother’s milk, which contains about 50% fat, helps the young seal grow quickly and put on the essential layer of blubber that helps seals survive in the cold. At four to six weeks, the pups are weaned, and mating for the next year begins. It’s a pretty busy life for a female seal, one I do not envy at all.

Ever since I was a kid at the Vancouver aquarium I’ve been enthralled by seals, their adorable liquid-black eyes making them one of the cutest animals in the aquarium. I was so happy to see that little guy swimming around the harbour yesterday, and I’m happier to post about his species.

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