When many think of the seal, they think of the funny flipper waving, ball balancing clowns of the circus and aquarium show. However, the real lives of seals are much more interesting.
A seal's daily life is filled with eating, sleeping, and evading predators. While resting in the water, they hang downward, with only their flippers in the air (to regulate heat). It is thought that this posture helps them be on the outlook for predators.
Harbor seal: The harbor seal eats fish, shrimp, squid, and octopus. Their main predators are orca, sharks, and Stellar sea lions. Pups have the additional threat of coyote and eagles. Harbor seals in marinas sometimes have a reddish coat, instead of their natural dark brownish-black coats, probably due to the minerals ingested from pollutants. Very wary of people, they have been known to abandon their pups if frightened.
Northern elephant seal:
Weighing the equivalent of two large trucks, and as long as two cars, these seals certainly live up to their name! The bulls develop a "trunk" when they reach breeding age (3-5 years) which is used to sound their challenges to other bulls. This large nose becomes fully developed by the time they are 9 years old. Though some may envy their free-love lifestyle (a male can mate with 50 or more females during a breeding season), they endure quite a bit of hardship. During the mating period, they sometimes go without food for 3 months. Their migration is 6000 miles. Bulls fight each other in bloody battles (they have 15cm long teeth which are used to rake each other). Once hunted to near-extinction, the elephant seal has bounced back to numbers over 100,000. They Eat squid, octopus, deep-water fish, small sharks and skates. Their predators are large sharks and orca.
Hawaiian monk seal:
Their Hawaiian name, 'ilio-holo-i-ka-uaua, means "the dog that runs in the rough" (seas). Very energetic in the water, they tend to look dead or sick while on land, but are just catching up on their sleep. Endangered, with numbers of only 500-1500. They eat eel, fish, octopus, and lobster. Their only predator is the shark. Because they never learned to fear man they don't run when approached. The Hawaiian government has developed protected areas prohibiting human interaction with the seals.
Guadalupe fur seal: (their Latin name means "bear headed") Also Endangered, with only 3,200 left in the wild. Guadalupe Island used to host this seal in such numbers that the shoreline's lava rock beaches had been worn smooth from the constant belly rubs from the seals. In 1894 sealers located a group of 15 fur seals at Guadalupe Island -- all that were known to exist -- and killed every single one. Scientists eventually found some live specimens, but the future of this seal is very shaky. No recovery plan for this species has been prepared, nor has a recovery team been established. The fact that I got to see one while on Kauai remains a moment I'll never forget.
Northern fur seal: Their biggest claim to fame, their fur, was also their biggest enemy. With a coat of 300,000 hairs per square inch, their pelts were extremely waterproof and beautiful. Remember those pictures of fur coats worn by males to football games in the 30's and 40's? Those were Northern fur seal coats. As open ocean seals, they can't get up onto rocks to rest, so they have developed a behavior called "jug handling", in which they pull their front and back flippers out of the water while bobbing on the surface. Record numbers of fur seals die during El Nino years due to changes in their environment. Their numbers are declining due to overfishing by commercial boats and entanglement in fishing nets.
Galapagos fur seal: The smallest pinnipeds, the females weigh about 28kg. They also have the lowest reproductive rate, making them slower to recover when their numbers decline. They eat fish and squid. Their numbers also declined during El Nino. A "no fishing" zone was established around the island in 1998 to help protect them.
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