Body Parts of a Sea Lion – Flippers, Ear Flaps and Crest

All 12 parts on the diagram

Show the list

The whole sea lion 6

Front flipper The front flippers push a sea lion through the water. On land they hold up its chest.
Hind flipper A sea lion turns its hind flippers forward to walk. A true seal cannot.
Tail The tail is small. The body tapers to it.
Neck An adult male has a thick neck. It bends far back to reach the hind flippers.
Coat The coat is short, sleek hair. A pup sheds its dark first coat for a paler one.
Claws The hind flippers carry claws. A sea lion grooms its coat with them.

The head up close 6

Eye Sea lions see in air and in water.
Whiskers Whiskers feel vibrations in the water. They can find a fish in the dark.
Snout A California sea lion has a long, narrow snout. It is also called the muzzle.
Nostrils The nostrils stay closed at rest. A sea lion opens them to breathe.
Ear flap Sea lions have small ear flaps. True seals have ear openings with no flaps.
Crest Adult males grow a crest on the forehead. Its hair often turns paler with age.

How this list was compiled: Every name checked on 2026-10-01 against (1) NOAA Fisheries, California Sea Lion, https://www.fisheries.noaa.gov/species/california-sea-lion (broad front flippers, long narrow snouts, forehead crests of subadult and adult males crowned with paler hair, visible ear flaps, claws on the hind flippers, coats); (2) Smithsonian's National Zoo and Conservation Biology Institute, California sea lion, https://nationalzoo.si.edu/animals/california-sea-lion (ear flaps, fore flippers and back flippers, claws on the back flippers used for grooming, a single hair coat, the crest of males from about 5 years old, muzzle, neck, body tapering to the tail, whiskers called vibrissae, nostrils closed at rest, ears that close underwater); (3) Wikipedia, text only: California sea lion, https://en.wikipedia.org/wiki/California_sea_lion, and Pinniped, https://en.wikipedia.org/wiki/Pinniped (ear flaps, foreflippers, hindflippers turned forward to walk on all fours, sagittal crest and thicker neck of males, long narrow muzzle, whiskers or vibrissae, nostrils closed underwater, small tail, fur coat); (4) NOAA National Ocean Service, What's the difference between seals and sea lions?, https://oceanservice.noaa.gov/facts/seal-sealion.html (sea lions have visible ear flaps and walk by rotating their hind flippers forward; true seals lack ear flaps and their hind flippers angle backward); (5) The Marine Mammal Center, California Sea Lion, https://www.marinemammalcenter.org/animal-care/learn-about-marine-mammals/pinnipeds/california-sea-lion (external ear flaps, large flippers used to walk on land, the sagittal crest of males from 4 years old). Licence: own work

The drawing: Drawn for this site on 2026-10-01 from plain geometry; nothing traced. Licence: own work

How it works

The top drawing is an adult male California sea lion sitting up on a rock. The bottom drawing is its head up close.

Read the full guide

From the flippers to the crest

Numbers 1 to 6 are on the whole sea lion: a front flipper, a hind flipper turned forward under the body, the tail, the neck, the coat and the claws. Numbers 7 to 12 are on the head: the eye, the whiskers, the snout, the nostrils, an ear flap and the crest.

Sea lion or seal? Look for ear flaps, and for hind flippers that turn forward to walk.
The crest marks an adult male. It gives him a high, domed forehead.

Questions and answers

What is the difference between a seal and a sea lion?

Look at the ears and the hind flippers. A sea lion has small ear flaps and turns its hind flippers forward to walk. A true seal has no ear flaps, and its hind flippers point backward, so on land it moves on its belly.

What is the bump on a sea lion's head?

A crest. Male California sea lions grow it along the top of the skull from about four or five years old, and it gives them a high, domed forehead. The hair on it often turns paler with age.

Do sea lions have ears?

Yes. A sea lion has a small ear flap on each side of its head, which is why sea lions and fur seals are called eared seals. The ears close underwater.

What are a sea lion's whiskers for?

Touch. The whiskers, also called vibrissae, pick up vibrations in the water, such as the movement of a fish swimming nearby, so a sea lion can find food in the dark.