There are two species of elephant seals, the northern and southern. Northern elephant seals can be found in California and Baja California, though they prefer to frequent offshore islands rather than the North American mainland.
Southern elephant seals live in sub-Antarctic and Antarctic waters that feature brutally cold conditions but are rich in the fish, squid, and other marine foods these seals enjoy. Southern elephant seals breed on land but spend their winters in the frigid Antarctic waters near the Antarctic pack ice.
Southern elephants are the largest of all seals. Males can be over 20 feet (6 meters) long and weigh up to 8,800 pounds (4,000 kilograms). But these massive pinnipeds aren't called elephant seals because of their size. They take their name from their trunklike inflatable snouts.
When breeding season arrives, male elephant seals define and defend territories. They collect a harem of 40 to 50 females, which are much smaller than their enormous mates. Males battle each other for mating dominance. Some encounters end with roaring and aggressive posturing, but many others turn into violent and bloody battles.
Sea elephants, as these seals are sometimes called, give birth in late winter to a single pup and nurse it for approximately a month. While suckling their young, females do not eat—both mother and child live off the energy stored in ample reserves of her blubber. Females give birth to a single pup each year after an 11-month pregnancy.
Elephant seals migrate in search of food, spending months at sea and often diving deep to forage. They return to their rookeries in winter to breed and give birth. Though both male and female elephant seals spend time at sea, their migration routes and feeding habits differ: Males follow a more consistent route while females vary their routes in pursuit of moving prey.
Elephant seals were aggressively hunted for their oil, and their numbers were once reduced to the brink of extinction. Fortunately, populations have rebounded under legal protections.