Northern Elephant Seal Info
Northern Elephant Seal Info | ||
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(Mirounga angustirostis) | ||
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Order: Pinnepedia Family: Phocidae Body: Northern elephant seals are the largest of all seals found in the northern hemisphere. The males are 14 to 16 feet long and can weigh a staggering 3000 to 5000 pounds, while the females are generally 9 to 12 feet in length and top the scales at a mere 900 to 1800 pounds. They are classified as true, or earless seals, and their hind flippers do not rotate forward. The adult male has a large trunk-like nose, which hangs loosly over his muzzle and is used to resonate when calling. The male also has a calloused chest shield which often bears scars form violent clashes with other males. Their color ranges from dark brown to a blond color depending on the age and sex of the seal. Elephant seals also exibit countershading with their dorsal surface being darker than their belly. Diet: The elephant seal is a predator and feeds on squid, fish, and octopus, which it will swallow whole. They can dive deeper than 5000 feet, with an average dive depth of 1500 feet. During pupping and molting periods, elephant seals will fast. Range: Large colonies of northern elephant seals once lived along the coast of the Pacific ocean from California to Baja, Mexico. Unfortunately, man discovered that the blubber of this seal was almost pure oil, and a single seal could yeild over two hundred gallons. This oil was a superior lubricant for machinery and within a rather short amount of time, the northern elephant seal was brought to the brink of extinction due to this human butchering. This wanton hunting ended in the 1890's, but only a few seals remained. In the 1930's, about 500 elephant seals were remaining, primarily in Mexican waters. Since that time, they have been totally protected by law, and have made a robust recovery, advancing their range northward again. The first stragglers to arrive in Alaska came in the mid 1960's, and now the males routinely venture as far north as the Aleutians in search of food. Life History: Breeding season for the northern elephant seal is from the start of December to the middle of March. In November, the adult males arrive on the beaches of California's mainland and coastal islands to sort out dominance for the right to breed. The males clash on the beaches and in the waters and the dominant or alpha male then collects his harem of females. These clashes can range from stand offs with only a show of snout sizes, to posturing and vocalization, or can be violent clashes leaving bloody gashes in the bodies of the participants. During the 3 months he will spend on shore, the alpha male will breed with as many females as possible. The impregnated females will eventually leave the beach for the summer but will return the next year during mid December. After an 11 month gestation period, the female will give birth to a single pup only days after returning to the haul out beach. Twinning has not been documented and a single pup is the rule. The newborns average 3 feet long and are from 60 to 80 pounds at birth. They have dark black hair and wrinkly skin. Within a month of being born, the pup can triple its weight. The cows milk is the richest of all mammals, with a 55 percent fat content. The mother fasts while nursing and will lose over a third of her body weight. She will nurse the pup for about a month and then will be in estrus and ready for mating a second time. Once she is re-impregnated, she will leave the beach and thus wean her pup. The pup is left to itself on the beach and tends to congregate with other pups. At around three and a half months, they are ready for their fist swim in the ocean. By this time, they generally weigh from 300 to 500 pounds. Elephant seal pups can fall prey to orcas and great white sharks. The yearlings that survive will return to the same beach in the fall for the haul out.
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View the Elephant Seal images. | ||
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