Difference Between Seals, Sea Lions, and Walruses

Seals, sea lions, and walruses are all carnivorous marine mammals that belong to the superfamily Pinnipedia. Because they share many physical traits and behaviors, people often confuse them. However, each belongs to a different family:

• Otariidae (Sea lions and fur seals)

• Phocidae (True seals)

• Odobenidae (Walruses)

Although they look similar at first glance, these animals have clear differences in size, anatomy, and lifestyle. Let’s break down the key distinctions and explore the characteristics of each.

Key Differences at a Glance

1. Size – Walruses are the largest, seals are the smallest, and sea lions fall in between.

2. Social Behavior – Sea lions are the most social and live in large, noisy colonies.

3. Tusks – Walruses are the only pinnipeds with long, prominent tusks.

4. Fur – Sea lions have more visible fur, seals have short or sparse fur, and walrus skin changes color depending on water temperature.

5. Habitat – Sea lions can spend long periods on land, seals come ashore less frequently, while walruses rely almost entirely on ice and water.

6. Ears – Sea lions have external ear flaps, while seals and walruses only have small ear openings.

Characteristics of Seals

• Belong to the Phocidae family (“true seals”).

• No external ears – only small ear holes.

• Hind flippers face backward, making them excellent swimmers but clumsy on land.

• Streamlined bodies with short forelimbs used as paddles.

• Diet: Mainly fish, squid, shellfish, and octopus.

• Keen eyesight helps them spot prey underwater.

• Predators: Orcas and sharks, though humans pose the biggest threat.

• Distribution: Found worldwide, mostly in colder waters. Cold-water seals eat more to maintain thick blubber layers, which can make up nearly 25% of their body weight.

Characteristics of Sea Lions

• Belong to the Otariidae family.

• External ears are a defining feature.

• More flexible hind limbs allow them to “walk” on land.

• Thick blubber for insulation and energy storage.

• Swimming speed: Up to 40 km/h (25 mph); clumsy but agile on land.

• Diving ability: Can reach 200 meters (656 ft) and stay underwater for 40 minutes.

• Diet: Squid, fish, penguins, seabirds, and sometimes seal pups.

• Predators: Mainly orcas and large sharks.

• Reproduction: Females give birth after an 11-month pregnancy.

• Social life: Extremely social, forming large colonies with strong territorial behavior.

• Distribution: Widespread along coastlines—from cold waters (New Zealand, Canada, Japan) to warmer regions (Mexico, California, Galápagos Islands).

Characteristics of Walruses

• Belong to the Odobenidae family.

• Large tusks: Longer in males, used for defense, dominance fights, and hauling their heavy bodies onto ice.

• Skin color changes: Brownish in normal conditions, but turns pink in warm water and pale in cold water. Older walruses often become lighter.

• Heavy blubber for insulation.

• Whiskers (vibrissae): Up to 700 around the muzzle, highly sensitive for detecting prey.

• Diet: Carnivorous, feeding on clams, crustaceans, mollusks, sea cucumbers, shrimp, and occasionally seal carcasses.

• Good vision and touch sense aid in hunting.

• Predators: Polar bears and orcas, though human hunting and climate change are major threats.

• Reproduction: Mate in the water; gestation lasts 15–16 months.

• Size: Second largest pinniped after elephant seals.

Summary

• Seals – Streamlined, no ear flaps, thick blubber, superb swimmers but awkward on land.

• Sea Lions – Have ear flaps, social and noisy, strong on both land and water, fast swimmers.

• Walruses – Largest of the three, instantly recognizable by their tusks and whiskers, highly dependent on sea ice.

All three play crucial roles in marine ecosystems as top predators and indicators of ocean health. Unfortunately, they face growing threats from climate change, habitat loss, and human exploitation. Protecting them is essential for the balance of polar and marine environments.

animal tags： seals sea lions walruses