NFB - Arctic Mission

by Isabelle Deslandes, Ship's doctor

There is a fascinating seabird that we have been lucky enough to observe frequently during our journey through the Arctic. It is the thick-billed murre, also known as the arctic or northern turr by Newfoundlanders. This seabird belongs to the Alcidae, or auk, family and is cousin to the guillemots and puffins. Murres resemble small penguins and seem to fill the same ecological positions in the northern oceans that penguins occupy in the southern hemisphere. They are found north of the 60th parallel in the Arctic regions of Canada, Alaska and Greenland.

The thick-billed murres, as their name suggests, have a stout, thick bill that is also sharp. In the summer their feathers are black on the back, neck and upper breast and shiny white underneath. Their wings are smaller than those of any other flying bird of their size, which explains why they are not very good fliers. As we have observed many times from SEDNA, they have to flap very fast on the top of water to take off, often bouncing off the tops of waves before getting airborne. Their maximum speed in the air is around 60 km/hr.

What is interesting about these birds is that they spend most of their lives at sea, sometimes 8 to 9 months at a time without touching land. They are very well adapted to this fluid medium and are long-distance swimmers. They travel about 6000 km a year, and a single journey can extend up to 1000 km. They seem to “fly” underwater by flapping away with their half-open wings. They dive straight down to depths averaging 100 m where they prey on pelagic fish, squids, krill, crustaceans and marine worms. The ocean becomes an underwater scene of playful aquatic ballets or for disputes and territorial battles. They are often observed chasing each other under water near their colonies.

Thick-billed murres come ashore only to breed and to raise their young. They look a little bit awkward on land because their feet are placed far back on their bodies, thus pushing their centre of gravity forward, which makes them shuffle along and flap their wings to keep balance. Most murres breed in huge colonies found mainly on steep cliffs, narrow ledges and offshore stacks where foxes and other predators cannot reach them.

They first breed at 5 years old. The female lays a single egg directly on a rocky ledge, with no nest. The incubation lasts about one month and is equally shared by both parents. After three weeks, the male leaves the colony with the chick to protect it from the predatory gulls that roam. As a close-knit pair, they will start a long migration to their wintering grounds (often in Newfoundland), initially swimming hundreds of kilometres as the chick does not learn to fly until it is two months old.

Murres can live a very long time, up to 25 or 30 years. Of course, oil spills spell catastrophe for the murres since they spend so much time on the water. Smeared in such a toxic substance, they lose their natural waterproofing and insulation and die. Some birds also see their lifespan shorten by getting caught in fish nets, while other become prey to traditional hunters off the East Coast of Canada.