Seals of the sub-Antarctic

A party of pinnipeds

Over the past month the pinniped action on Macquarie Island has been simply incredible. Pinniped refers to anything fin-footed and this includes any marine mammals with front and rear flippers. On Macca we have five species that have been seen recently. The radio call “Sea lion on the isthmus” once provoked a rush for cameras from one end of the station to other, ensuring you had your long camera lens to watch the creatures from a distance; expeditioners not wanting to be included on the menu as the sea lions went about their day hunting penguins. However, these days we are all getting a bit blasé about seeing one of the world’s rarest sea lions. We have also been lucky enough to see some leopard seals and multiple species of fur seals hauling out around the coast.

The most common sighting this month has been the New Zealand sea lions. Also known as Hooker's due to their scientific name Phocarctos hookeri, they can be quite intimidating, with adult males growing to 3.5m long and weighing up to 450kgs! As their name suggests, they breed only in New Zealand and have a population estimated at around 3000 individuals. The first time you see one is always simply incredible. The pure strength and magnificence of these creatures leaves you awestruck. They are fast and strong and with a nickname like ‘the beast’ you can imagine the terrifying feeling these creatures invoke. Their diet is diverse including fish, squid and penguins, and a few specialise in hunting fur seals. While sightings of male sea lions are increasing here, and we’ve been lucky to witness up to three of them ‘playing’ on the beach, their population is in decline and they are listed as a threatened species at a local and global level. Another reminder that we are privileged to live here with wildlife on our doorstep, and it is always worth grabbing your camera.

Leopard seals are a phocid or true seal, unlike our sea lion friends, and are more streamlined and lack external ears. According to the history books, they were once commonly found on the coastline of Macca. These days they are considered a vagrant visitor only occasionally seen here, so any sighting does induce a rush for the cameras. For some of us it's the first time we have seen this caterpillar like creature. Leopard seals are mottled, with white fur sporting pretty patterns of brown and black spots. They appear sleepy and docile resting on the beach, until an elephant seal comes close and you see them open their teeth filled mouth to 180 degrees! Their teeth are designed to strain krill, however they also eat anything from penguins to platypus! Different to all other seals that are sexually dimorphic (different sizes for males and females) leopard seal females are slightly bigger than males, weighing 320kgs and 370kgs respectively. They breed on the sea ice around Antarctica in summer and little is known about these elusive creatures.

And last, but not least, we also have fur seals, my favourite. We have three species that reside here, Antarctic fur seals, sub-Antarctic fur seals and long-nosed fur seals (previously called New Zealand fur seals). All three species are in the Arctophoca genus, translating to ‘bear seal’. Antarctic fur seals are the most prevalent and breed here along with sub-Antarctic fur seals, however confirmed hybridisation (breeding between species) has occurred in the past. The number of fur seals was decimated during the sealing era for pelts, with numbers estimated to be in the hundreds of thousands. In the 1800s, over an 18 month period, 120,000 fur seals were taken and within 10 years they were almost gone. Today, fur seal numbers are in the hundreds, and they are slowly increasing and expanding their breeding territory. Another great reason for Macquarie Island to continue as a nature reserve. What a privilege to live and work here amongst these incredible creatures.

Oh and there are elephant seals too… more on those in spring.

Kim Kliska, Wildlife Ranger,Tasmanian Parks and Wildlife Service - and your friendly neighbourhood Macca crew.