Elephant Seal

Elephant seals are the largest pinniped (seal or sea lion) along the Northern California coast. They breed in large numbers every winter at Ano Nuevo State Reserve in San Mateo County.

During the breeding season, massive, four thousand pound bulls fight. The winners of these fights, the most dominant bulls, have primary breeding rights over the females.

These impressive battles usually only last for a brief moment, but in rare cases can last for over an hour. Fights are usually initiated by trumpeting, then followed by chest batting, head butting, or biting. Fights can be bloody, and although rare, bite wounds to the skull can be fatal.

Females arrive pregnant in December or January, giving birth to their pups about 4-5 days after hitting on shore.

After giving birth, females nurse their pups for thirty days. Nursing pups consume milk that is 55% fat. In contrast most people drink skim or low fat milk. Whole milk, which is 4% fat, seems a bit thick for most people’s taste. Elephant seal pups are guzzling milk that is the consistency of mayonnaise. After just 11 days of nursing, pups double in weight.

By the end of March, most of the bulls and females have returned to the open ocean, leaving only the weaners, weaned pups, on shore.

The River Otter Ecology Project is a registered 501 (c)(3) EIN #45-4997526 non-profit organization dedicated to the welfare of river otters and our watershed. We receive no government funding, and depend solely on financial support from our friends. Our organization is not affiliated with any other otter-related research group or community outreach organization.

© 2018 River Otter Ecology Project

Contact
River Otter Ecology Project
PO Box 103
Forest Knolls, CA  94933
General email