The largest seal in the world tips the scales at more than 8,800 pounds (4,000 kg) and up to 20 feet (6 m) long, making the Southern Elephant Seal the world’s largest seal. This species edges out its closest relative, the Northern Elephant Seal, which is the largest seal in the Northern Hemisphere, weighing up to 4,400 pounds (2,000 kg) and 13 feet (4 m).
Southern elephant seals are named after the large proboscis (nose) of the adult males, which is used to make loud roaring sounds, especially during the mating season.
They are big and cumbersome on land, but are superb swimmers and divers. Biologists have recorded them diving up to two kilometers deep and holding their breath under water for up to two hours.