Red-footed geese are moving to new breeding grounds in the Arctic
Jürgen Peter Keldsen
Some red-footed geese began migrating to the Arctic island of Novaya Zemlya in the summer to breed. The island is nearly 1,000 kilometers away from his usual breeding grounds, Svalbard.
Conditions on Novaya Zemlya, a Russian island in the Arctic Circle, were too cold for geese to breed. But global warming has made spring conditions earlier, making the island suitable, says his Jesper Madsen of Aarhus University in Denmark. Over the course of 15 years, the group established a new travel route to Novaya Zemlya and new stops along the way.
“This is a big surprise,” Madsen says. “It’s really great to see this.”
Several other birds are changing their habitats in response to global warming, but this is the most dramatic change of this species ever observed in migratory birds, he says.
There are two populations of red-footed geese (Anser brachyrhynchus). It winters in England and Ireland and migrates to Iceland and Greenland in the summer to breed.
Others overwinter in the Netherlands and Denmark and migrate to Svalbard to breed. In spring, this population flies most of the length of Norway, resting in places before making the long flight over the sea to Svalbard. Birds return via this route in the fall.
However, in the 1990s, people started finding individuals and small flocks of red-footed geese in southern Sweden in spring and autumn. By the 2000s, larger herds were being discovered more frequently.
In 2018 and 2019, Madsen and his colleagues GPS-tagged 21 geese to find out where they were headed. Half of them flew to the part of Novaya Zemlya that was used until 1990 to test nuclear bombs. Madsen says even Russian biologists aren’t allowed to go there, so without the GPS trackers their presence would never have been discovered.
Rather than flying along Norway, these birds are flying over Sweden and Finland, and GPS data also show that they are nesting there. Many people leave behind descendants and return home.
Researchers estimate that the Novaya Zemlya population has already grown to about 4,000 birds. Some of these geese had previously traveled to Svalbard and switched routes, as some birds along the route from Denmark to Svalbard are regularly tagged with non-GPS tags. I understand.
The team’s hypothesis is that these geese learned new locomotion by copying the tiger moose (answer fabaris). Some taiga mothflies fly to Novaya Zemlya in late spring to molt and exchange flight feathers rather than reproduce.
“That’s the best explanation we have,” says Madsen. If correct, it would be a rare example of the transmission of cultural knowledge between species.
Madsen believes that change is happening not only because of Novaya Zemlya’s warming, but also because traditional migration routes are becoming more difficult. Red-footed geese now have to compete with barnacle geese (steep recopsis), and food availability is also decreasing due to changes in agricultural practices.
“This is truly a remarkable study that combines traditional and time-honored bird observation and counting with tagging, GPS and climate data to reveal remarkable new stories,” said the RSPB Conservation Science Center in the UK. Richard Gregory of was not involved in the research.
“On the one hand, it offers hope that migratory species may be able to adapt to climate change in a relatively short period of time, but it also raises alarm bells about the pace of change,” he says.
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