Sea Otters
The Aquarium exhibits two species of sea otter, the Northern and the Southern. Sea otters, extinct on the Oregon coast since the early 1900s, have now returned to the state through the Oregon Coast Aquarium. Visitors can learn about sea otters natural behaviors both from animal husbandry demonstrations and from Aquarium interpreters stationed at the exhibit.
Sea otters were once found along the Pacific coast from California to Alaska. An imperiled population still exists in California, a more vigorous population can be found in Alaska and stable populations live in Washington and British Columbia. Sea otters range from 50 to 100 pounds and have a luxuriant pelt averaging one million hairs per square inch—more in one inch than exists on an entire human head. Voracious eaters, sea otters consume food totaling up to 25 percent of their body weight each day. They are the only marine mammals that do not have a layer of blubber to keep them warm. A sea otter will spend an average of three hours per day performing grooming behaviors and relies on an extremely dense fur coat, which traps air next to its skin to insulate it against cold water. Rolling, combing and blowing air into its fur are all included in a sea otter's grooming methods. Its coat must be extensively groomed in order for it to remain waterproof, otherwise cold sea water can reach the skin and the animal will suffer from hypothermia.
- Northern Sea Otter: Currently there is one northern sea otter living at the Oregon Coast Aquarium. Aialik (pronounced eye-Al-ik) is a male, who weighs over 70 pounds and is still growing. He nuzzles, nibbles and plays with his enrichment toys throughout the day, and usually swims during his regular feedings.
Their diet consists of shrimp, squid, crab, butter clams and surf clams, along with supplementary vitamins. When they reach adulthood male otters may weigh between 70 and 100 pounds. Aialik is a lucky sea otter, according to the U.S. Fish and Wildlife Service, once a baby sea otter is taken from the wild it cannot be returned. Their policy dictates that orphaned animals that cannot find homes in zoos or aquariums must be euthanized.
- Southern Sea Otter: Two southern sea otters are living at the Oregon Coast Aquarium. Hunter, a male southern sea otter that was rehabilitated at the Monterey Bay Aquarium in California. Although healthy, his release to the wild was not a success; he was begging for food at local piers and jumping into kayaks. A home has been found for him here along with our other male otters. Hunter’s adventure in Monterey was featured on Discovery.com.
Judge is a male sea otter that was found abandoned as a tiny pup on the central coast of California. He was also rehabilitated at the Monterey Bay Aquarium. They released and monitored him using a radio tracking implant. He was recaptured five times in 2 1/2 years and deemed non-releasable due to the inability to feed himself.
- Collaborative rehabilitation: Our otters, along with other stranded and injured marine animals, are playing an important role in rehabilitation. Through direct communication with zoos and aquariums across the country, and around the world, sick or injured animals, which previously had little hope of surviving, are being saved and in some cases re-introduced into the wild.
Working collaboratively with the Seattle Aquarium and the Monterey Bay Aquarium, the Oregon Coast Aquarium received the latest information about caring for infant sea otters. This practical information was extremely useful to the Aquarium’s husbandry staff and is one reason that our otters have responded so well. These cooperative relationships with zoos and aquariums are crucial for the successful rehabilitation of marine mammals, seabirds, sea turtles and other marine animals.
- The Exhibit: The main sea otter pool holds 65,000 gallons of seawater. Exhibit water is filtered at a rate of 1,800 gallons per minute, or 2.6 million gallons daily. The rocky pool is 12 feet deep at its deepest. Surrounding it are haul-out beaches, where a sea otter can leave the water for areas both visible and not visible to the viewing public. Swim-through tunnel, nooks, crannies and logs provide the otters with exploration opportunities. Five vantage points offer the public both above-water and below-water views.
An additional holding pool in a non-public area behind the exhibit holds 7,000 gallons. This pool is used when the large pool is being cleaned or maintained, and for wellness care, medical attention and special feedings.
- Diet: A sea otter's diet at the Aquarium consists exclusively of fresh-frozen food fit for human consumption, including shrimp, crab, and clams. Annual cost per animal: $11,000.
- Water quality: Every 40 minutes, all the exhibit's water runs through high-rate sand filters and an ozone filtration system. Water quality is monitored daily, and weekly bacteria counts are taken to ensure that bacteria levels are within stringent government guidelines.
- Medical and wellness care: Each animal is routinely weighed to make sure they are maintaining ideal body weight, an important element in their overall health.
- Marine mammal enrichment program: This innovative program combines environmental enrichment devices (toys) and human interaction, to keep a curious sea otter mentally as well as physically fit. Keeping an otter engaged and healthy is an important aspect of animal care. To help provide a stimulating environment, diverse enrichment devices are introduced into the exhibit. Boat bumpers, buoys, a whirly hose, a children’s play gym and even beer kegs are added to the exhibit to make them more interactive. Frequently toys placed behind the scenes are retrieved by an otter and then pushed around the pool. In an aquarium environment, an otter's surroundings must be as dynamic as possible to maintain good physical and mental health. The Aquarium’s animal staff randomly rotates the toys in and out of the exhibit to prevent boredom. It is important to make sure the toys are always fun and exciting.
- Playtime: Other toys include PVC pipe fittings and pieces of kelp (to manipulate); ice blocks containing clams and other food bits (to chew and manipulate); extra-sturdy plastic balls, plastic milk crates and trash can lids (for manipulation); a stream of water from a hose (to play with and swim through); and periodic feeding from the pool bottom rather than hand feeding (allows foraging and collecting behaviors).
