Mammals
Southern Elephant Seal
Mirounga leonina · also called elephant seal
Weighing more than four tonnes at its largest, a southern elephant seal dwarfs every other seal species on Earth, diving over a kilometre deep and staying submerged for more than an hour in relentless pursuit of squid across the Southern Ocean.
Overview
The southern elephant seal, Mirounga leonina, is the largest seal species on Earth, native to ocean, coastal, and polar habitat across the Southern Ocean and sub-Antarctic islands. Its record-breaking size, extraordinary diving ability, and fierce male competition for mates make it one of the most physically extreme marine mammals found anywhere in the world’s oceans.
A giant built for the deep
Far from a coastal loafer, the southern elephant seal spends much of its life at extraordinary depth, its massive size supporting dives that rival or exceed those of many dedicated deep-diving whale species in search of the squid it depends on for survival.
Status
Least Concern, having recovered substantially since historical sealing pressures ended and remaining widespread across suitable Southern Ocean habitat.
Southern Elephant Seal: common questions
How big can a southern elephant seal get?
This species is the largest of all seal species, with the biggest bulls capable of exceeding four tonnes in weight, dwarfing every other pinniped species known, including its closest relatives.
Why is it called the elephant seal?
Adult males develop a large, inflatable, trunk-like nose used to amplify roaring calls during the breeding season, a feature resembling an elephant's trunk that gave the species its common name.
How deep can a southern elephant seal dive?
This species can dive to depths exceeding a kilometre and remain submerged for well over an hour, ranking among the deepest and longest divers of any marine mammal in search of squid and fish.
Why is there such a big size difference between male and female southern elephant seals?
This species shows an extreme size difference between the sexes largely because dominant bulls fight fiercely for control of large groups of females during the breeding season, favouring greater size and aggression in males over many generations.