Tuesday, December 7, 2010

Will I See You In December?

Swimming in the ocean every morning is always a different experience, and whether it's the tides and current, the weather, or the creatures I encounter, no two days are ever the same.  I have never kept track of every beautiful sunrise or calm ocean swim but I have tried to track every day I've had an encounter with a seal and, over the years, this has yielded a fairly consistent pattern.  I say try because, while seals appear to be curious and usually make themselves visible, they are also cautious and can be deliberately shy or coy about their presence.

Harbour Seal
While there are 19 different species of seals within the family Phocidae, also referred to as "true seals" or "earless seals" the one most common to the Vancouver area is the Harbour seal.  Generally staying within a 20 kilometer range, they're an easy going non-territorial bunch, appearing to share haulout spots, foraging for fish and crustaceans in a common area, and even swapping mates amongst themselves from one year to the next.  Pups are born from between June and September, followed by everyone having their annual moulting, and then in late fall it's back to mating season. 

This all ties in quite nicely with my own logbook, which shows the seals are less likely to make contact in the summer, when presumably they are off having their babies and suntanning in more protected locations, and then returning in December to check out the mating action.  Sometimes it even seems I'm being considered as a potential candidate because they come very close by, often swimming right underneath me, while batting their eyelashes and making splashes.  Only trouble is I don't know if they think I'm male or female, and I can't really tell what they are either.

Stellar Sea Lions
The seal superfamily known as Pinnipedia contains 3 distinct groups of sea mammals.  The Phocidae already mentioned, the Odobenidae otherwise known as the walrus, and the Otariidae or "eared seals" which are the sea lions. Of the 16 different species, the California sea lion and the Stellar sea lion are the ones found cruising our local waters.  Besides the fact that one group has ears and the other doesn't, there are some other striking differences that make it easy to tell the difference between seals and sea lions.

The most obvious difference of course is size, with the Harbour seals weighing in at between 120-370 pounds and the Stellar sea lions between 1300-2500 pounds.  On the other hand a male Elephant seal can easily get up to 5,000 pounds (even though the females are only around 1,400 pounds) so seals can be just as big.  But the most distinguishing feature is their flippers.  The two back flippers on a seal form a tail like structure that aids them in being very efficient in water but very awkward on land and their front flippers are quite small.  The sea lion on the other hand has very large, powerful front flippers, that are its primary source of propulsion, and its rear flippers can turn forward so it can move on all fours quite easily on land.





There is another big difference between the Harbour seals and the Stellar or California sea lions and that is the distance they will go to forage for food.  Harbour seals live in the same place year round taking advantage of whatever seasonally abundant prey happens to be in the neighbourhood while sea lions are quite prepared to go on long swim-abouts if the eating is good.  So every winter, when the Pacific Herring make their way to selected spawing locations on the West Coast, the sea lions are waiting for them at haulouts along the way. 

One of these haulouts is just off Hornby Island where, starting in December, the males from California head north and the Stellar males from Alaska head south, (leaving the women and children behind at the home rookeries) to congregate for a big bachelor party and herring feast.  This is a popular spot for scuba divers to interact with these friendly beasts, who act like playful dogs, and want nothing more than a little diversion, while they wait for the herring to arrive.  Occasionally these sea lions take a detour to check out the sights and sounds around the Vancouver area as well and last weekend I found myself playing with one on a dive off Whytecliff Park.   

Sea Lions & Nelson at Hornby Island

And that's another difference between seals and sea lions.  Seals will come up close to check you out whether you are swimming or scuba diving but they won't play or interact on anything close to the level of a sea lion.  It's said that sea lions have the intelligence of a dolphin and it appears they can be quite easily trained to do a variety of tasks that range from performances in public Aquariums to guard duty at Naval stations.

Nonetheless, between the seals showing up for the start of mating season and the sea lions getting ready for their annual bachelor party I always look forward to seeing my aquatic companions in December and every encounter is always special.

2 comments:

  1. Your blog is wonderful and so informative. I think I'll tell my grandchildren about it and they can learn without realising that it's a lesson.
    diana

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  2. This is a great story. I love the little seals in the ocean and never tire seeing them while cruising past in our boat. Super story with so much to learn about them. Well done..

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