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Steller Cove Exhibit
Mira the Elephant Seal | Steller's Sea Lions | Sea Otters | Research Station | Tide Pool |
Kelp Forest | Exhibit Art & Poetry | Video
 Mira, a blind female elephant seal, moved into her new home at Oregon Zoo’s Steller Cove exhibit in 2002. The six-month-old was found stranded on the Northern California coast shortly after being weaned from her mother. She was taken to the North Coast Marine Mammal Center in Crescent City, California. where an examination revealed that her retinas were underdeveloped, and it was determined that she could not be returned to the wild. She was facing euthanasia until the Oregon Zoo offered her a home.
According to Chris Pfefferkorn, zoological curator at the Oregon Zoo, finding a home in a zoological facility was her only alternative.
North Coast Marine Mammal Center approached Oregon Zoo about housing the seal.
“ We talked about it, did some research, and after visiting the animal, decided she would make a great addition to the zoo,” said Pfefferkorn.
Caring for a blind animal requires marine life keepers to adjust their regular feeding and training practices. For example, noise-making beads were added to the target-training pole and food is placed in the animal’s mouth rather than tossed toward her.
Mira is named for her species. “The scientific name of the elephant seal is Mirounga angustirostris,” explained JoEllen Marshall, senior marine life keeper. “We got creative and came up with Mira.”
Elephant seals are named for their large noses, which resemble an elephant's trunk. Males begin developing this enlarged nose, or proboscis, at sexual maturity (about three to five years), and it is fully developed by seven to nine years. Adult males may grow to more than 13 feet in length and weigh up to 4,500 pounds. The females are much smaller at 10 feet in length and 1,500 pounds. The northern elephant seal is the second largest seal in the world, after the southern elephant seal.
FACT SHEET:
RANGE/HABITAT: Northern elephant seals are found in the North Pacific, from Baja California, Mexico to the Gulf of Alaska and Aleutian Islands. During the breeding season, they live on beaches on offshore islands and a few remote spots on the mainland. The rest of the year, except for molting periods, the elephant seal lives well off shore (up to 5,000 miles, or 8,000 km), commonly descending to over 5,000 feet (1,524 m) below the ocean's surface.
BEHAVIOR: While living in the open ocean, northern elephant seals spend a lot of time diving, up to two hours at a time. They rarely spend more than four minutes at the surface of the water between dives. It is believed that they eat deep-water, bottom-dwelling marine animals such as ratfish, swell sharks, spiny dogfish, eels, rockfish, and squid. Elephant seals molt each year between April and August, shedding not only their hair but also the upper layer of their. This is known as catastrophic molt.
MATING AND BREEDING: Each winter, elephant seals arrive at their breeding beaches in Mexico and California. Males are the first to arrive and they fight each other to establish dominance. During this time, dominant males will often inflate their noses and produce a noise that sounds like a drum to warn lesser males away. Females soon arrive, and associate with dominant males. Several days after coming onto the beaches, the females give birth to the pups they have been carrying since last year. Pups weigh 75 pounds (35 kg) or more and are about four feet (1.25 m) in length. The pups nurse for about 28 days, generally gaining about 10 lbs (4.5 kg) a day. Around the time of weaning, the mother will mate with one or more of the dominant males. After the nursing period, the mother returns to sea. For the next two months, weaned pups, called weaners, remain on rookery beaches, venturing into the water for short periods of time, and perfecting their swimming and feeding abilities. Eventually, the pups will learn to feed on squid, fish, and occasionally small sharks.
STATUS: The northern elephant seal is a conservation success story. They were hunted to the brink of extinction, primarily for their blubber, which was used for lamp oil. By 1910, it is estimated that there were less than 100 elephant seals, all found on Guadalupe Island off Baja California, Mexico. Today, the northern elephant seal population is over 150,000 and is probably near the size it was before they were over-hunted.
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