Sea Lion: The Flippered Sea-Dwelling Lion

Sea lions are predators, and some of them roar. The adult males of all but one sea lion species also grow thick and long fur from the back of their head down to their shoulders, resembling the mane commonly found adorning the head and neck of their land-locked namesake. Indeed, this is how sea lions got their name.

Whereas lions walk with paws on tippy toes, however, sea lions primarily walk on land using their hind and front flippers. While sea lions can walk, moreover, they are more graceful and agile swimmers.

Read on to learn about the sea lion’s habitat, diet, size, and adaptations.

Sea lions are amphibious marine mammals that live in the Pacific and Atlantic Ocean basins. You can find them in:

• The North Pacific Ocean between Russia and Alaska (Steller sea lions)
• The western and southern coasts of Australia (Australian sea lions)
• The western, eastern and southern coasts of South America (South American sea lions)
• The islands on the southern end of New Zealand (New Zealand sea lions)
• Along British Columbia down to central Mexico (California sea lions)
• In the waters of Ecuador, particularly around the Galapagos Islands and Isla de Plata (Galapagos sea lions)

Sea lions live in saltwater and choose their habitat based on food availability, land access, and temperature. Sea lions need access to a beach or shore to rest, mate, molt, and give birth. They like temperate and subpolar climates and avoid the icy waters of the polar regions.

The scientific classification of sea lions is a clue to sea lion’s major characteristics. From below, you can deduce that sea lions are meat-eating (Carnivora) and placental (Eutheria) mammals (Mammalia) with a backbone (Vertebrata).

• Kingdom: Animalia
• Phylum: Chordata
• Subphylum: Vertebrata
• Class: Mammalia
• Subclass: Theria
• Infraclass: Eutheria
• Order: Carnivora
• Order: Caniformia
• Family: Otariidae
• Subfamily: Pinnipedia
• Genus: Eumetopias, Neophoca, Otaria, Phocarctos, Zalophus
• Species: Eumetopias jubatus, Neophoca cinerea, Otaria flavescens, Phocarctos hookeri, Zalophus californianus, Zalophus wollebaeki

There used to be another Zalophus species: Z. japonicus or the Japanese sea lion. There have been no documented sightings of the Japanese sea lion after 1951.

Sea lions and seals are all pinnipeds (i.e., fin-footed animals under the Pinnipedia superfamily). True seals (i.e., earless seals) are from the Phocidae family. Fur seals are from the Otariidae family, the same family as sea lions.

True seals and sea lions have obvious differences. These include the following:

• Sea lions have outer ear flaps; seals don’t.
• Sea lions have large flippers; seals have small flippers.
• Sea lions “walk” on land; seals crawl on their bellies.
• Sea lions make loud sounds like barks, growls, and grunts and are very communicative; seals mainly grunt.

Fur seals look like sea lions. In fact, fur seals and sea lions are collectively known as eared seals. They, too, have ear flaps and can walk on land using their hind and fore flippers.

However, fur seals have longer whiskers than sea lions. There’s also a difference in fur seal and sea lion sizes; sea lions tend to be bigger. Furthermore, sea lions have a longer nose and eyes that are set further back on their heads.

Sea lions eat fish and cephalopods like squid, cuttlefish, and octopus. They are opportunistic and eat almost any fish and invertebrates, including shellfish and crustaceans. They swallow their prey whole, so sea lion teeth are used for grasping and biting, not chewing.

Hunting methods

Sea lions typically hunt in groups, working together to crowd fish in and feast on stragglers at the peripheries. However, when fishes are scarce, sea lions hunt individually.

Sea lions in freshwater

Sea lions are marine animals, but they may venture into freshwater. Some California sea lions from southern California and Steller sea lions from Alaska come to the Columbia River to prey on migratory fishes like lamprey, steelhead, sturgeon, and salmon.

Animals, including us humans, adapt their bodies through time to improve their chances of survival. Sea lions are no exception. Below are a few of their fascinating adaptations.

Swimming

• Galapagos sea lions have a lower metabolic rate than other sea lions. This lets them dive deeper and longer (almost 600 m for more than 10 minutes) when hunting for food.
• Australian sea lions swallow small stones (gastroliths); it is believed this helps them balance their weight when diving for food.

Behavior

• Galapagos sea lions have learned to adapt to human settlements. They scavenge for fish and food scraps discarded by fishing boats and prey on fish attracted by the lights on these boats.
• Some female Australian sea lions would protect the young of another, even going so far as to foster or adopt an orphaned pup. Some babysit, taking turns to protect a group of pups.

Physiology

• Australian sea lions have a thick layer of fur and blubber to protect them from the cold, subantarctic waters.
• Sea lions have ear flaps that can turn so they open downward, preventing water from getting into their ears when they swim or dive.
• The eyes have lenses that can focus refracted light underwater and pupils that can open wide to let in plenty of light, giving sea lions acute eyesight underwater.
• Sea lions have very sensitive whiskers called vibrissae that let them detect the speed and direction of prey based only on the small waves (i.e., wake) the prey leaves behind. These whiskers can move forward and backward and touch objects to gauge size, shape, and texture.

Observe sea lions in real life at SeaWorld Yas Island, Abu Dhabi.

Watch as they dive, swim, and relax on the rocky shores of Rocky Point. Get up close and personal with them and their close cousins, the seals, when you go on a Sea Lion Encounter.

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