The 6 Seal Species in Antarctica and How to See Them

Weddell seals are, by a wide margin, the most commonly seen seal along the Antarctic Peninsula, and they're also the ones most likely to win visitors over on looks alone: round heads, big dark eyes, and a permanently mild, slightly bemused expression. They spend most of their lives associated with fast ice — ice attached to land or ice shelves rather than the drifting pack — and use their teeth to keep breathing holes open through the winter, a habit that wears their teeth down over a lifetime.

They're also exceptional divers, capable of staying submerged for close to an hour and reaching depths approaching 720 meters while hunting fish such as Antarctic cod. Weddell seals are unusually vocal underwater, producing trills, chirps, and other complex sounds that scientists believe function as territorial calls between males defending breeding areas beneath the ice. Most pups are born from September through November, making early-season trips a good bet for seeing mothers with young.

Despite the name, crabeater seals barely eat crab at all — their diet is almost entirely Antarctic krill, filtered through unusual, multi-pointed teeth that interlock to sieve the water much like a strainer. That misleading name aside, crabeaters have a genuine claim to fame: current population estimates run well into the millions, making them by some measures the most abundant seal species, and possibly the most abundant large wild mammal, on the entire planet.

You'll only ever see a crabeater seal on pack ice, never on land, and never in a proper colony — they tend to be loosely scattered or found in small, mother-pup pairs rather than clustered groups. Their long, pointed snouts and silvery-brown coats make them fairly easy to tell apart from the rounder-faced Weddell seal once you know what to look for. Young crabeaters are a favored prey item of leopard seals, and it's common to see individuals bearing long healed scars from a leopard seal attack they survived as pups.

If one Antarctic seal tops most travelers' wish lists, it's this one. The leopard seal is one of Antarctica's two apex predators, alongside the orca, and it looks the part: a long, powerful, almost reptilian body built for speed in the water, and a wide, gaping jaw capable of taking down prey many times its own size. Unusually among seals, females are the larger sex, occasionally reaching 3.8 meters — bigger than most male leopard seals.

Their diet ranges from krill and fish up to penguins and the pups of other seal species, and the most dramatic wildlife encounters in Antarctica often happen at the edge of a penguin colony, where a leopard seal patrols just offshore waiting for birds entering or leaving the water. Leopard seals are largely solitary, and unlike the ice-colony species on this list, you're as likely to spot one resting alone on a single ice floe as hunting actively in open water.

Of the six species on this list, the Ross seal is the one you're least likely to encounter, and expedition guides treat any sighting as a genuinely rare event worth radioing the whole ship about. They live deep within the heaviest pack ice, far from the more accessible coastal waters that cruise ships and Zodiacs typically travel, and their population is thought to be small relative to the other five species, though exact numbers remain poorly studied precisely because they're so hard to reach.

Physically, Ross seals are distinctive: unusually large eyes suited to hunting squid in the low light of deep water, a short, thick neck that gives them a somewhat compressed profile, and a set of unusual underwater vocalizations that have been described as sounding almost like distant sirens. Most confirmed sightings come from deep pack-ice voyages into the Weddell Sea rather than standard Peninsula itineraries, so seeing one is largely a matter of luck and a specialist route.

Nothing on this list, or in the entire seal family worldwide, comes close to the size of a bull southern elephant seal. Large males can weigh up to four tons and stretch past five meters — a genuinely startling amount of animal to see hauled out on a beach, especially next to the females, which are dramatically smaller. Unlike the four pack-ice species above, elephant seals breed on land, in dense colonies on the beaches of sub-Antarctic islands, with South Georgia hosting some of the largest gatherings anywhere.

During the breeding season, dominant bulls fight loud, physical battles over harems that can include dozens of females, using their inflatable proboscis — the "elephant" in the name — to bellow warnings at rivals. Outside of breeding season, elephant seals return to the same beaches to molt, a process that leaves them looking patchy and somewhat worse for wear as they shed their old coat in large sheets.

The only eared seal on this list, and by far the smallest, the Antarctic fur seal is also the species with the most dramatic conservation story. Hunted to near extinction for its pelt during the sealing era of the early 19th century, the population has rebounded to an estimated several million animals today, with South Georgia serving as its single most important breeding site. Unlike the true seals covered above, fur seals have visible external ears and can rotate their hind flippers forward, letting them move across land and rock with far more agility than any other species here.

Visit South Georgia at the height of the breeding season, typically November, and beaches can be so densely packed with territorial male fur seals that landing safely becomes genuinely difficult for expedition staff — a striking sight for an animal that came so close to disappearing entirely a little over a century ago. Later in the season, the same beaches fill with fast, curious fur seal pups, which are considerably less territorial than the adult males and often the highlight of a South Georgia landing.