March 20th, 2023
Often seen lounging around on rocky islands in coastal BC, Steller sea lions have earned a reputation for being lazy. Sure, they relish relaxation and sunshine — but they are also incredibly adept at swimming and hunting. Steller sea lions are the world’s largest species of sea lions and one of the ocean’s top predators, pursued only by killer whales and sharks.
SOCIAL LIfe OF STELLER SEA LIONS
Similar to other species of sea lions, Stellers are highly social mammals. It’s common to see them congregating in large clusters on beaches and rocky islands close to shore. These sites are called haulouts, commonly serving as communal resting grounds outside of peak breeding season. It’s common to see Stellers sprawled on top of one another, heads nested here and there, as they soak up the sunshine together.
What do you call a group of Steller sea lions? Well, it depends on the context! When on land, they are a colony; in water, they are a raft. During breeding season, mature males (bulls) establish groups of adult females (cows) to form a group known as a harem.
AMONG THE PACIFIC OCEAN’S TOP PREDATORS
While they spend most of their time on land, Steller sea lions frequently venture out to sea for food. Mature males need about 30-35 kilograms of food per day, which is enough to keep them busy! Steller sea lions sometimes hunt alone, but oftentimes they work in large groups to control the movement of schooling fish. Night time is best for feeding, as sleeping fish make for an easier target. Stellers feed on more than 100 species of fish, usually opting for whatever’s abundant in the region at the time. The large whiskers on the tip of their nose help them navigate and sense prey underwater. Stellers can dive about 300 meters deep and last for up to 8 minutes before resurfacing for air.
Perhaps unsuspecting, their flipper game is strong. Steller sea lions belong to a group of mammals known as pinnipeds, meaning “feather footed”. Their front flippers are longer and wider, serving as the engine power while swimming. The back flippers are actually capable of turning forward, which allows them to effectively walk and climb on land. It’s no easy feat, given mature male Stellers can weigh up to 2500 pounds!
BREEDING STELLERS MEAN BUSINESS
“Are sea lions dangerous?” remains one of the most frequently asked questions about these hefty mammals. Stellers aren’t inherently dangerous to humans when we give them space, but they commonly display aggressive behaviour toward other wildlife during breeding season. From spring to late summer every year, Steller sea lions gather in massive, dense colonies in order to seek safety and protection from land predators. These terrestrial sites, known as rookeries, are primarily used for mating, giving birth and resting, though can be visited year round.
Rookeries are controlled by dominant males working around the clock to establish and defend the land in hopes of attracting females. While males are sexually mature between 3-8 years of age, it’s often not until they reach 10 when they have the size and strength to successfully hold a territory. Dedication runs deep during this time of year, so much so that males will often fast for more than a month to stand their ground. Though these efforts may seem drastic, strong males typically attract a harem of 3 to 20 females. Mothers usually birth one pup at a time and can easily pick it out from the crowd through scent, touch and vocalization.
WHERE TO SEE STELLER SEA LIONS IN BC
British Columbia is the only place in Canada where you’ll find Steller sea lions. It’s home to some of the largest congregations of Stellers in the world. Some noteworthy regions to explore: northeastern tip of Vancouver Island, southern tip of Haida Gwaii, and off the northern mainland coast. Our coastal BC sea kayaking tours offer excellent viewing opportunities, as Steller sea lions often gather on isolated rocks away from the shoreline.
Salish Sea Wild: Steller Sea Lions, the Grizzlies of the Sea. SeaDoc society explores the life of the dominant Steller sea lion in coastal British Columbia.
Steller Sea Lions Create a Giant Raft. Captured during a National Geographic Quest in Alaska, a group of Stellers join together to create a raft.