An adventurer running around the world
The Arctic tern is a great traveler, and spends most of the year commuting, with long stretches over the ocean. Their breeding areas cover both the arctic and the southern polar regions. In Europe, during the summer months, it can be found from Brittany in the south, to Iceland, Greenland, and Svalbard in the north.
Come autumn, the terns head south toward Antarctica as they stay through the northern winter. However, they do not fly directly from north to south, and a single bird is known to have covered nearly 100,000 kilometers, or twice the circumference of the planet.
A great adventure
“When terns reach Antarctica, they stay close to the edge of the ice, and gradually move eastward,” says Gumundur A. Guðmundsson, an animal ecologist at the Natural History Institute of Iceland. Swedish and Dutch birds walk all the way towards Australia, but Icelandic and Greenland birds return earlier to the Weddell Sea in the Antarctic Arctic. From there they set off north in March and after a month and a half, they reached their destination in our country. ”
In the case of Iceland, terns declare spring in the latter part of April, when they reach the nest. When the chicks are ready to go in August, they fly south, but not in a straight line, but rather in an S-shaped pathway. One of the well-known stops is Cape Town in South Africa in November.
On their way to their nesting areas of Iceland and Greenland, they have been known to make stops in Brazil and crossed the Andes mountain range. “It’s a big adventure,” says Mr Guðmundsson.
A front row seat in a planetary crises
However, he is concerned about the decline in Iceland’s tern population – which currently stands at around 250,000 nesting couples – over the past few decades, with climate change being the likely culprit.
Due to the warming of the ocean, the algae bloom earlier in the year, and it is too early for young sand eels to feed. This means that the stock of sand eel, an important food source for migratory seabirds, has collapsed in the seas around Iceland.
Although the tern is not in danger of extinction in the short term, enough concerns have been raised to add it to the IUCN Red List of Threatened Species.
Inger Andersen, Executive Director of the United Nations Environment Program (United Nations Environment ProgramMigratory birds have a “first-row seat in the triple planetary crisis of climate change, loss of biodiversity and pollution,” he says.
“Climate change is altering and disrupting bird migration patterns,” adds Ms. Anderson. “The destruction of the natural world threatens these pollinators, which are essential to food security and well-being. Pollution, whether in bodies of water, land or air, has proven to be toxic to migratory birds.”