Description & Characteristics:
Ross seals are the least common of the four Antarctic seals. Until the 1970’s, fewer than 100 people had actually observed one. Virtually inaccessible among the heavy pack ice surrounding the Antarctic continent, Ross seals have been protected from large-scale commercial hunting, which had decimated other seal populations in the 18th and 19th centuries. Much remains to be learned about this solitary species, which is becoming better studied as powerful icebreakers more frequently penetrate the densest interior regions of the pack ice.
In appearance, Ross seals have dark grey to chestnut coats with buff undersides. Adults molt in January or February. They have relatively short heads and snouts, with very large eyes. Distinctive light and dark chestnut or chocolate stripes can be observed from the chin to the chest. These throat markings are clearly visible when the animal is disturbed. When approached it throws its head back, inflates its throat, and opens its small mouth revealing sharp, recurved incisors and canines. Ross seals also have the shortest hair of any seal. Females are typically larger than the males and most adults have small pale scars around the neck and shoulders.
Specializing primarily on cephalopods, particularly squid, Ross seals’ limited populations may be due to a lack of significant feeding resources. Fish and krill are preyed upon as well, but in lesser amounts. The Ross seal is believed to be able to feed at depths of several hundred feet, where its large eyes aid underwater vision.
Ross seals reach sexual maturity between three and five years. Pups are born on pack ice in November, and are approximately 4 feet long and weigh about 60 pounds. Though rarely observed, the pups are born with dark brown fur which is lighter on the underside. The female nurses her pup alone for about 25 days after which the pup is weaned.
Ross seals have distinctive vocalizations which they use to attract a mate or warn off intruders. These include: a trilling, siren-like call and a warbling-type sound known as ‘chugging.’
Ross seals are preyed upon by Killer whales and Leopard seals.