A good chunk of the cottage season is very important to B.C.’s Steller sea lion. But that’s because between May and August, the big pinnipeds (aquatic, fin-footed mammals) stick close to shore as they gather in rookeries to mate and give birth. The world’s largest rookery is at B.C.’s Triangle Island off the northwestern tip of Vancouver Island.
Stellers are the largest of all sea lions—they weigh just over a ton. It’s the big bulls that father most of the offspring during a given breeding season. The mating system is “polygynous”: males breed with multiple females in the group, and couples don’t pair off.
June is peak pupping time: a.k.a. lots of babies! At birth, Stellers are already three feet long and weigh up to 50 lbs. They can almost immediately crawl and swim, but usually don’t enter the water until week four. Pups nurse for about a year. Then, it’s time to start learning to eat: typically a wide variety of fish (Pacific herring, capelin, sand lance, Atka mackerel, walleye, pollock…). Young Stellers learn to rip apart larger prey and swallow smaller fish whole. A big sea lion has a bit appetite. Adults consume about six per cent of their body weight in food every day.
Sometimes, Steller sea lions can be easy to confuse with harbour seals. They have similar, whisker-covered faces. But sea lions are larger, with longer flippers; have small, external ear flaps; and tend to be more vocal and gregarious than seals. Stellers can also “walk” by supporting their weight on their front flippers and tucking their back flippers under their bodies. Seals, on the other hand, shuffle or drag-and-slide their bodies across land. And Steller sea lions have that shaggy neck of fur—a mane—and instead of barking like a seal, they roar. Like a lion, of course.