Harbor Seals (phoca vitulina) are 4.5 to 5.5 feet long and dive 300 feet deep. Northern Elephant Seals (mirounga angustirostris) are named for their funny shaped snouts and their size. Males are 20 feet long, and females are 11 feet long. Northern Fur Seals (callorhinus ursinus) are 4.5 to 6.5 feet long.