Antarctic petrel, snow petrel and southern petrel. These are the birds that live in the mountain area in the Norwegian area of Dronning Maud Land in Antarctica. The snow petrel stays in burrows and under rocks, while the Antarctic petrel and southern petrel lay eggs directly on the ground in the mountainsides. In March last year, news told the story of the empty bird’s nest at Svarthamaren. Blackhammer has been known to have the largest colony of Antarctic petrels in the world. But last year there was no one there. Only a few snow petrels and almost no southern grebes. Now they are back. But there are fewer than before. – It was completely empty. We walk steeply up through a clock in the hill behind the Norwegian research station Troll. Svarthamaren is around 100 kilometers away. Here at Troll, it is the snow petrels who “reside”. Inside the ura there are dozens of nests. – There is a chicken in here, says Harald Steen. He is a biologist and director of research at the Norwegian Polar Institute. – There is a snow petrel in here, says biologist Harald Steen, who is research director at the Norwegian Polar Institute. Photo: Eivind Molde / news He has heard a faint sound, and looks under the stone. Far inside, through a narrow opening, he sees the tiny bird, perhaps a couple of weeks old. – The situation last year was the same here as at Svarthamaren. It was empty. Completely empty. The Antarctic summer 2021–2022 was very special. Now we have begun to understand more of what happened, says Steen. Snow petrel in its nest inside a clock at the Troll research station. Photo: Eivind Molde / news Extreme weather conditions – We think that the birds came here to the mountain area as usual when the breeding season started. But during December 2021 there were very many strong storms in the area. This probably led to the birds getting tired and giving up, says Steen. Now Steen, Sébastien Descamps, Joanna Sulich and several other bird researchers have published a scientific article about the birds and the extreme weather to which they were exposed. The article is published in the journal “Current Biology”. They describe what happened as very unusual. It is not often that storms wipe out entire colonies. A series of storms, with extreme wind strength combined with heavy snowfall, made it unlivable at the nesting sites. They therefore returned to the Southern Ocean, according to the researchers. – But don’t tolerate the birds over here? – Well, they tolerate a lot. But it may also be that the spring was bad, that they did not build up the circulation industry they needed. They were perhaps a little on edge when they arrived. And when the storms got on top of this, it was too much for them, says Steen. Long journey to find food The petrels feed on krill and fish that they find in the Southern Ocean. From the mountain area in Dronning Maud Land, it is around 20 miles to the ice edge. Then the birds have to go further out over the sea, perhaps another 20 miles, to get to the “food dish”. Then an equally long journey back to the nest awaits. They are gone for a couple of days. They collect the food in a sack. Fish and krill turn into an oil that the baby bird in the nest gets. Snow petrel hovering above Troll. Photo: Stein Tronstad / Norwegian Polar Institute Sharp decline in population Birds come to the mountains in Dronning Maud Land in late autumn to breed. They usually do not leave the nest until February or March when the young are able to fly. Then they set course for the Southern Ocean, where they live the rest of the year. This season, there has been full life again in the bird mountains. But there are fewer birds than before. – There is no acute danger to the population. But there is therefore a decline in the number of Antarctic petrels from over 200,000 to approx. 70,000, says Harald Steen. Climate scientists state that global warming leads to more extreme weather. It occurs more often, and becomes more intense. Steen is excited about how the bird populations in Dronning Maud Land will develop in the future. Antarctic petrel in Jutulsessen. Photo: Stein Tronstad / Norwegian Polar Institute
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