Avian Island is our study site for Adélie penguins in Marguerite Bay, but this time of year the seals outnumber the penguins.
Seals are important predators in the Antarctic, and where the hunting is good, or where they have easy access to the water (called a seal chute), they can be abundant.
The Antarctic has six species of seals. Four are thought of as "pack ice seals," because they can be found far from shore on the seasonal sea ice that forms every Antarctic winter. More on them later.
For now, we'll introduce the seals on Avian Island — the southern fur and the southern elephant seal. They are hugely different in size, habits, and personality.
Fur seals were hunted almost to extinction in the early 1900s. In fact, they were believed extinct until a small group was seen in the northern peninsular area a few years after the hunting was stopped. Since then, their numbers have increased to well more than a million.
Fur seals are the personality champs of the Antarctic seals. They are nearly always in small groups, and one or more will sometimes charge when you walk by them. Intimidating? At four to six feet in length, yes. Most of the time they stop after a few feet, but sometimes you need to shout or bang two rocks together to halt the charge. Waving a penguin net also helps.
Fur seals have visible ears and can move their rear flippers around to stand on them, so they are pretty fast on land. Their growl sounds like a dog: a low, throaty rumble.
Like all seals, they are quite graceful in the water. They feed on krill and the occasional fish.
Elephant seals are enormous and don't move around much. A mature male can weigh more than two tons.
During breeding season they can be quite active, with a large male maintaining a harem. We are in the "offseason," which is a time for rest and replenishment of body stores.
Sleepy as they seem, it's a bad idea to get too close — they move faster than you think.
Elephant seals are "true seals," which means their rear flippers can't be brought under the body to stand on, so they have to wriggle like a huge worm.
Clumsy and huge as they may seem, the elephants are champion divers among all seals. They feed almost entirely on squid and adult males can dive more than a mile.
Their large eyes are equipment for dealing with the darkness of the ocean's depths. Nature never ceases to amaze.
From Marguerite Bay, we'll be stopping briefly at the British Antarctic base just north of the bay, in Rothera, and then it's on to our next site at Renaud Island.