Northern Elephant Seal

Northern Elephant Seal, courtsey NOAA

SPECIES FACTS

Scientific Name
Mirounga angustirostris
Life Expectancy
13-19 years

BIRTH FACTS

Weight
75 pounds (35 kg)
Length
4 feet (1.25 m)

ADULT FEMALE FACTS

Weight
1,300-2,000 (590kg- 907kg)
Length
7-12 feet (2.1-3.6 m)

ADULT MALE FACTS

Weight
4,400 pounds (1996 kg)
Length
12-16 feet (3.6-3.9 m)

Northern elephant seals are the largest of the “true”, or “earless”, seals in all of the Northern Hemisphere. The have a large range in the Pacific Ocean and can be seen from Alaska to Mexico. Northern elephant seals spend most of the year, about 9 months, in the ocean and can only be seen on land during pupping season. In Washington, it is rare to see them ashore. The population estimate for the California stock of Northern elephant seals is around 180,000. With over a 13,000 mile roundtrip migrations, they have one of the longest migrations of any animals.

HOW TO SPOT

On the Whale Trail, Northern elephant seals can be seen at sea while they are at the surface between their long dives. They have been known to look like deadheads, or logs, in the ocean sort of bouncing up and down a couple times and then disappearing. Mature males are easily identified by their large proboscis.

WHEN AND WHERE TO SEE

Elephant seals come ashore in the winter to mate and give birth. Look for elephant seal rookeries on the central California coast at Pigeon Point Lighthouse near San Simeon and Ano Nuevo State Beach, north of Santa Cruz. Mature males are easily spotted by their large noses that resemble elephant trunks.

April through August, elephant seals return to beaches to shed their skin, or molt. Look for groups of molting males at northern California sites like McKerrecher State Park.

In Washington, adult females can be in their feeding areas of Washington and Oregon, during their time between spring/summer molting and winter breeding season. September-November is a good time to see them from shore.

RANGE

Northern elephant seals range from Alaska, down the west coast to Mexico. The largest colonies are found off southern California and the Channel Islands. Males feed in the Aleutian Islands and Gulf of Alaska, while females travel further to offshore waters of Washington and Oregon. Adult females will return to California or Mexico, and go ashore between March and August to molt. Males return slightly after females.

Male Northern Elephant Seal, courtsey Chris Yates NOAA

BIOLOGY

Adult Northern elephant seals are light brown to black in color. They lack external ear flaps and have smaller fore flippers than other pinnipeds. A key physical characters is the male’s elongated snout, called a proboscis. Once males reach puberty at 7 years old they grow a large nose, as well as thick and robust necks that are lighter in color compared to their darker bodies. Female’s snouts grow just beyond the mouth and have smoother necks. Both sexes have black whiskers and V-shaped hind flippers. Northern elephant seals will molt their fur and shed the short dense fur and patches of old skin. Molting takes 4-5 weeks. When they haul out for molting season they will stay there for a few weeks. During this time, they look to be in bad shape, however it is normal. Please do not attempt to approach what looks like an animal in distress.

BIRTH FACTS

Mating occurs from December to March and pups are born in early winter, from December to January. The gestation period is around 11 months. Breeding primarily occurs on offshore islands of California and Mexico, such as the Channel Islands, and at rookeries on the central California coast. Females will come ashore only a few days before giving birth to her pup. Pups are born black and will molt into a silver coat after 4-6 weeks, once they are weened. The female will breed again before her pup leaves and she returns to the ocean. During mating season, Northern elephant seals fast and can lose up to 36% of their body weight. Most elephant seals will return to natal rookeries when they reach sexual maturity.

SOCIAL STRUCTURE AND BEHAVIOR

Northern elephant seals are polygamous breeders, meaning during the mating season males establish a dominance over a large group of females. They have a social hierarchy based on the male’s harems, which is the grouping of females. Males start to form harems around 9-10 years old and battle for status among the adult males. They use their large nose to makes sounds and vocally threatening other males.

Northern elephant seals feed mainly on squid and fishes, however, their diet also consists of rays and sharks. They can dive to depth ranging from 1,000-2,500 feet (305-762m) for lengths of 20-30 minutes. Northern elephant seals only take short breaks at the surface which is when they are likely to be seen from shore.

STATUS

Northern elephant seals are protected under the Marine Mammal Protection Act and are not considered endangered or threatened. They were once thought to be extinct after commercial sealing which occurs in the 1800s. The U.S and Mexico stock of Northern elephant seals has survived and derived by the few hundred individuals not targeted during commercial sealing. The population began to increase in the 1900s.