AUKS – penguins of the north
The most numerous birds on Svalbard are auks, represented by the little auk, brünnich’s guillemot, black guillemot and the Atlantic puffin. They nest in the hundreds of thousands and can be seen in many of the imposing bird cliffs along the coast of the archipelago, or far out at sea.
Auks are important to the ecology of Svalbard since they carry food, such as fish and crustaceans, from the sea to the colonies on shore. Bird droppings have an important fertilizing effect, providing fresh green vegetation near the bird colonies.
Auks are often considered the Northern Hemisphere’s penguins because of their similar appearance. However, genetically they are more closely related to seagulls and waders.
Because there are still land predators in the Arctic (no land predators exists in the Antarctic), auks have retained the ability to fly. They breed in large colonies, most species choosing steep cliffs safe from foxes and polar bears.
The name penguin originally came from the now extinct great auk of the Northern Hemisphere. Europeans used to call the great auk ‘Penguiyn’. When they travelled to the Southern Hemisphere and met true penguins for the first time they were so reminded of the great auk that the explorers gave them the penguin name.Alkefjellet in Hinlopen, on the east coast of Spitsbergen, is home to as many as 90.000 pairs of brünnich’s guillemot. Copyright: Roy Mangersnes
The brünnich’s guillemot (Thick-billed murre in the US) is a compact and strong bird; it has around 14,000 feathers on it’s body compared to the much large herring gull which has around 6000.
Brünnich’s guillemots breed on the narrow ledges of steep cliffs. They do not make a nest but rather place their single egg directly onto to the rock. The egg is asymmetrically shaped with one end much more pointed than the other. The egg therefore just rolls in circles rather than falling off the ledge.
Guillemots equipped with depth recorders have demonstrated that they can dive as deep as 200 meters. However most dives are between 10–30 meters.
Brünnich’s guillemot chicks leave the colony before they are able to fly. Some colonies are so far from the coast that the chicks are not able to jump or glide all the way to sea. Instead they have to survive a crash into the ground sometimes from as high as 150 metres.
The guillemot chicks remain unable to fly for several weeks. They partly swim, partly drift with the current and are guided by their father towards good feeding areas. Over a couple of weeks they can swim as far as 600 km from their colony.
Eggs from brünnich’s and common guillemots were in earlier times an important food source for Svalbard hunters and fishermen. In the 1950s hunters could collect between 50-60 000 annually. This tradition stopped around 1970.
Brünnich’s guillemot are very social birds, that spend a lot of time on the water. Copyright: Roy Mangersnes
The little auk is the only North Atlantic alcid that almost exclusively feeds on zooplankton. Being relatively nutrient poor the little auks have to eat around 80% of its own body weight each day.
The preferred prey of the little auk is a small crustacean (copepode) – the Calanus glacialis. This species is much more nutrient rich than alternative copepodes, but lives only in cold Arctic water. Rising sea temperatures secondary to climate change means that the little auk will have to rely on less nutrient-rich prey, making the species vulnerable.
During the breeding season a colony of 20 000 little auks will shift around 1000 kilograms of biomass from sea to land. This biomass in the form of guano drains into the soil providing it with valuable nutrients. This highlights the importance of seabirds in the Svalbard ecosystem. It also explains why slopes below bird cliffs in Svalbard are so green!
The little auk is the smallest of the auks, but also the most numerous. Over one million pairs breed in Svalbard in over 200 colonies. Most of the auks are migrating southwest to Iceland, South- western Greenland and Newfoundland in Canada.
Little auks can be seen to take multiple laps over the colony before they actually land. This behavior probably evolved to make ensure the landing site is free from arctic foxes.
The little auk is vulnerable to bad weather. Following periods of heavy storms in their wintering grounds it is not unusual to find little auks hundreds of kilometres inland – a long way from the nearest sea.
The little auk is the most common seabird in the North Atlantic, and arguably in the world (population estimates of its closest contestant – the Antarctic prion of the Southern Ocean are a close call). Because of its breeding behaviour of birds they are extremely difficult to count and so depending on the source there are substantial differences in the estimated number. The Svalbard population alone has probably more than a million birds. The largest known colony is at Thule (Greenland) and has been estimated to consist of 30 million breeding pairs! However – other sources estimate that the total world population is only 15 million breeding pairs.
Little auks sitting on a outcrop overlooking Bjørndalen, just south of Longyearbyen. Copyright: Roy Mangersnes
Atlantic puffins dig burrows into to the ground to make their nests. On the mainland, a puffin colony can comprise a hundred thousands of birds. However in Svalbard the ground is more or less frozen all year round (permafrost) so the birds are unable to dig their own burrow. They are therefore forced to make their nests in already exisiting cracks and crevasses on the mountain. As a result you never find large altlantic puffin colonies in Svalbard.
After being out at sea all winter the atlantic puffin returns to its colony on a certain date each spring. This date varies somewhat from colony to colony depending on where it is situated. In some places on the Norwegian mainland the locals holds a big party to celebrate the puffins on their homecoming date. This reflects that in earlier times the puffin was considered to be an important food source for these remote settlements. Today the puffin is protected both in Norway and Svalbard – but the partying still goes on.
The Atlantic puffin is famous for its colourful bill. However during winter these beautiful colours disappear almost completely and the bill dramatically reduces in size.
Atlantic puffin of the subspecies naumanni is slightly larger than the mainland Europe nominate species. Copyright: Roy Mangersnes
The black guillemot is the only North Atlantic alcid that turns almost white during winter. Copyright: Roy Mangersnes