California Sea Lions, the Barking Comeback Kids of the Coast
California sea lions were once hunted for oil and hides. Now there are about 300,000 of them barking from buoys and docks. How they live, what eats them and why some years they starve.
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Barking from buoys, flopping all over docks and driving boat owners crazy, California sea lions (Zalophus californianus) are about as Californian as it gets. They’re smart, curious and a lot like big wet dogs. And despite some bad years, the population has made a remarkable recovery over the last few decades, and now they’re one of the most common marine mammals on the coast. Go into almost any California harbor and you’ll see one poking its head up to take a loud breath.
Sea lions belong to the Otariidae, the eared seals. They’re built for the water, with sleek bodies, strong flippers and blubber to keep warm. Males can weigh up to about 800 pounds (363 kg) and grow around 8 feet (2.4 meters) long, while females are much smaller, around 250 pounds (113 kg) and 6 feet (1.8 meters). People call them seals all the time, but they’re not, and it’s easy to tell the difference. Sea lions have little ear flaps and long front flippers they can use to “walk” on land. True seals have no ear flaps and wriggle along on their bellies.
NOAA
They range from the Gulf of California to British Columbia and gather in big, noisy colonies on beaches and rocky islands, especially the Channel Islands. In breeding season, males stake out territories and fight and bark to keep rivals away. Females have one pup a year and nurse it for months.
They’ll eat whatever’s around, mostly anchovies, herring, salmon and squid. They have great underwater vision and can dive more than 900 feet (275 meters) to find food, and an adult male can eat 5 to 8 percent of his body weight in a day.
Sea lions on a buoy in Orange County. (Erik Olsen)
Their big enemy is the white shark (Carcharodon carcharias), which goes after sea lions, especially young, inexperienced ones. And there are more white sharks off California now. With more seals and sea lions to eat on the West Coast and legal protection, white sharks have made a big comeback. One study found as many as 40 juvenile white sharks hanging out just 50 feet from shore at some popular Southern California beaches. That sounds scary, but records show that only 15 people have been killed by sharks in California since the 1950s.
Sea lions weren’t always so common. In the 1800s and early 1900s, they were killed in huge numbers for oil, hides and even their whiskers, which were sold as pipe cleaners, and later for pet food, and their numbers dropped sharply.
The turning point was the Marine Mammal Protection Act of 1972, which made it illegal to hunt or harass them. Marine protected areas and efforts to cut pollution and fishing conflicts helped too. Today there are roughly 300,000 of them.
Sea lions in Newport Beach. Credit Erik Olsen
They still have bad years. When the ocean warms, especially during El Niño, the fish they eat move or disappear, and sea lions starve. In some years, hundreds of skinny, starving pups have washed up on California beaches.
With the ocean warming, those die-offs may get more common, which is why scientists keep a close eye on their numbers.
Still, it’s pretty great to live alongside them. They’re like puppies of the sea: curious, playful and very social. They’ve come back from the brink once, and as long as we give them room, they’ll keep barking from our buoys for a long time. Just don’t let one climb onto your boat.
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