South American Sea Lions are also sometimes known as Patagonian Sea Lions or simply the Southern Sea Lion. Some Spanish-speaking areas refer to them as lobo marino - Sea Wolf.

These sea lions have a large range and can be found on South American coasts from southern Ecuador on the Pacific, all the way around to Southern Brazil on the Atlantic coast. The two places you are most likely to have a close encounter on your Antarctic expedition cruise are in the waters of the Beagle Channel and shore around Ushuaia in Argentina and in the Falkland Islands.

There are thought to be over a quarter of a million South American Sea Lions, but their habits away from their breeding colonies are relatively unknown. The overall population seems stable, but numbers in the Falklands and on the Patagonian coasts are reducing.

Their diet consists mainly of fish, but they will also take squid and octopus. Southern Sea Lions have been seen preying on penguins, and also taking young South American Fur Seal pups. In terms of their own predation, they are only attacked by orcas and by sharks.

Adult male South American Sea Lions can grow to over 2.7m (9ft) long and weigh over 340kg (750lb). They develop the largest mane of all the sea lion species, making them the most “lion-like”. Females are much smaller, growing to around 1.8m (6ft) in length and weighing at most half as much as the males.

Sea Lions gather between December and February to give birth and then to mate. January is the peak time to observe sea lion breeding behavior. Sea lion males will fight for territory on beaches and to keep a harem of females. Unsuccessful males will sometimes group together to try and raid the harem of dominant males causing a huge disturbance on the breeding beaches and sometimes separating pups from mothers. If you are visiting the region in peak sea lion breeding season your naturalist guides may well land you in different areas of the beach from usual, or avoid some active colonies altogether.