Monday, December 21, 2009

Harbor Seals and Sea Lions

Harbor Seals
Harbor seals are the most commonly seen seals along Oregon’s coast. Their population is increasing because of federal law protection along the U.S. coast.

Size: Average five feet in length; adult males weigh around 200 pounds and females 170 pounds.

Description: Most are bluish-gray with black spots and irregular white rings and loops.
Habitat: Temperate, ice-free coastal waters of the North Pacific and North Atlantic oceans; found from Alaska south to Baja, California in eastern Pacific.

Behavior: Spend equal amounts of time on land and sea, are graceful swimmers, but movement on land is clumsy. Seldom venture far from water; often seen resting on bay and estuary sandbars at low tide. Move in wriggling manner on land, pulling their bodies along with their short fore limbs. Haul-out areas on protected tidal rocks and reefs along outer coast are hubs of daily activity and annual cycles, providing for resting, reproductive activities, births, caring for the young, and the annual molt. Can dive to 600 feet and remain underwater for 12-15 minutes. Make little noise. Considered non-migratory.

Diet: Herring, smelt, flatfishes, lampreys, sculpins, squid and octopus.
Lifespan: Up to 20 years.

California Sea Lions
The California sea lion has thick fur plus a dense layer of under-hairs that stay dry when the animal is underwater and a thick layer of blubber to help maintain its body temperature.

Size: Males weigh an average of 800 pounds and are seven to eight feet long. Females weigh much less, around 200 pounds and measure an average of five feet in length.

Discription: Mature males have dark red or chocolate brown fur that may appear black when wet. Females retain a light brown fur coloring. Males develop sagital crests, bony bumps on the top of their skulls that turn lighter as they age. A long snout gives the California sea lion an almost dog-like face.

Habitat: Bays, estuaries and waters near shore, from southern Mexico to southwestern Canada. Most of population migrates to southern California and Baja peninsula during breeding season. Females are joined by males during the breeding season, May-August.

Behavior: Males migrate to winter feeding areas off Oregon, Washington and Canada, sometimes taking over docks, piers and marinas. Seldom travel more than 10 miles offshore. Usually haul out on beaches or rocky shorelines in closely packed groups. Walk on land with rear flippers tucked under them. Sometimes seen floating together on the ocean surface, with flippers in air, in an action called “rafting”. Very vocal, make barking sounds.

Diet: Squid, Octopus, schooling fish, rockfish, salmon.
Lifespan: 17-18 years, predators are orcas and great white sharks.