Ross SealOmmatophoca rossiiWhere and when to see them

The Ross seal is one of Antarctica's least frequently observed seals, associated especially with remote, consolidated pack ice. Its small head, large eyes and thick neck create a distinctive appearance when it rests on an ice floe. Unlike seals commonly encountered near Antarctic visitor routes, it is sparsely distributed and difficult to study. Much of its life history remains less thoroughly documented than that of other Antarctic seals.

Size

1.7–2.4 m long

Weight

130–220 kg

Lifespan

Not reliably established

Status

Least Concern

Usually solitary on the ice, Ross seals spend much of their time at sea and can travel beyond the pack into open Southern Ocean waters. They haul out for breeding and moulting, with females nursing a single pup during a short spring period. Adults produce elaborate calls used in acoustic studies. When disturbed on ice, an animal may raise its head and inflate its conspicuous throat region. They are known for their unique, trilling vocalizations that can carry long distances underwater and through the ice. When startled, a Ross seal may also hiss or growl while inflating its throat. Their solitary nature makes group sightings exceptionally uncommon.

• Its genus name refers to its conspicuous eyes.
• It is the smallest of the four seals closely associated with Antarctic pack ice.
• Its repertoire includes distinctive, sweeping vocalizations.
• Tracking has shown that some individuals spend extended periods far from the ice.

The Antarctic visitor season, roughly November through March, provides the practical deck-observation window. Ross seals remain exceptionally unpredictable even then because their preferred pack ice is often inaccessible. This travel window does not imply that ordinary peninsula itineraries reach breeding habitat. Encounters are extremely rare even during the austral summer months due to their preference for dense pack ice. Expedition cruise itineraries focusing on the deep Weddell Sea or East Antarctica might offer a slightly higher chance of a distant sighting. Even then, successful sightings are more a matter of luck and persistence.

Ross seals inhabit the Southern Ocean around Antarctica, using dense pack ice as resting and breeding habitat. They also range through deep offshore water beyond the ice edge. Their preference for remote ice conditions places much suitable habitat outside ordinary coastal visitor access. They are thought to prefer very heavy, consolidated pack ice for hauling out. This makes them one of the least frequently encountered pinniped species in the Southern Ocean. Their distribution is circumpolar, primarily in the East Antarctic and Weddell Sea sectors.

Squid and fish form the main documented diet, with some crustaceans also recorded. Large eyes are consistent with finding prey in dim conditions. Knowledge comes from limited samples and tracking work, so prey proportions should not be generalized across the entire Antarctic range. Despite their large eyes, their diving capabilities and feeding depths are not well understood due to their remote habitat. The high proportion of squid in their diet suggests they are effective nocturnal or deep-water hunters. Stomach content analysis has also revealed krill, suggesting opportunistic feeding.

Common name

Ross Seal

Scientific name

Ommatophoca rossii

Animal group

Mammals

Size

1.7–2.4 m long

Weight

130–220 kg

Lifespan

Not reliably established

Status

Least Concern

Identification

Compared with crabeater and Weddell seals, the Ross seal has a smaller head, unusually large eyes, a thick neck and prominent pale streaking along the throat. The Ross seal's head often appears disproportionately small compared to its very thick neck and body. Distinctive pale stripes on the throat can be a key identifying feature, running from the chin to the chest. Its small, peg-like teeth are also unique among Antarctic seals, though not visible from a distance.