Marine Life Gallery

Northern Elephant Seal, Mirounga angustirostris
Elephant seals derive their name from their great size and from the male's large proboscis, which is used in making extraordinarily loud roaring noises, especially during the mating competition. There is a great sexual dimorphism in size, with the males (bulls) reaching five meters in length, much bigger than the females (cows), who average about three meters. The males average 16 ft (5 m) and 5,000 lb (2,300 kg), while the females average 1,400 lb (640 kg). Correspondingly, there is a highly polygynous mating system, with a successful male able to impregnate up to 50 females in one season. Beginning in the 1700s Northern elephant seals were hunted extensively almost to extinction by the end of the 19th century, being prized for oil that could be made from their blubber, and the population may have fallen as low as 100 to 1000. Finding refuge in Mexican waters, by the turn of the century, there was only a sole surviving rookery, on Guadalupe Island, Mexico; and this colony was granted protection by the Mexican government. Since the early 20th century, they have been protected by law in both Mexico and in the United States. Subsequently the U.S. protection was strengthened after passage of the Marine Mammal Protection Act, and numbers have now recovered to over 100,000.