The earth is constantly rotating, we experience the cycle of day and night every day, and roughly form the life law of sunrise and sunset. Many creatures on Earth also follow this routine, and although there are still many creatures that have developed the habit of day and night, they still have to experience the alternation of day and night.
However, it is said that there is an Arctic tern in the world, but it can live in the day for a long time, and is also known as the day bird. Let's get to know it today!
The Arctic Tern is a species of seabird. Although it is named "Arctic", its main range of activities includes the North Pole and the South Pole. Among them, the Arctic region is the breeding area of arctic terns, where the baby terns are born, while the Antarctic region is where they stay when they spend the winter.
Arctic terns
When it is summer in the Northern Hemisphere, Arctic terns breed in the Arctic Circle, catching small fish and shrimp in the sea for food; when winter comes, the water along the coast freezes, and arctic terns set off to start long-distance migration.
They fly south, across the equator, around the globe for half a week, to the icy Antarctica, where they enjoy the southern hemisphere summer. It wasn't until winter in the southern hemisphere came that they flew north again and back to the North Pole.
Schematic diagram of the migration of Arctic terns
Arctic terns travel back and forth between the two poles once a year, traveling more than 40,000 kilometers. Arguably, of all the migratory animals on Earth, arctic terns travel the most distant routes. The North and South Poles are so far apart that it is not easy to travel back and forth between the two poles once. The reason why the Arctic tern can fly such a long distance is because its tail is forked, its wings are narrow and long, and the pair of wings can obtain much greater buoyancy than other birds when flying in the air, so that the terns fly with less effort.
As a migratory bird, Arctic terns love to move in flocks, often gathering tens of thousands of them, mainly for collective defense and enhancing deterrence against the enemy. Like mink and foxes, they are cunning and agile, and they like to steal the eggs and young birds of Arctic terns. But in the face of such a large flock of birds, they also have to think twice. In fact, even powerful polar bears will give up three points in front of the huge flock of Arctic tern birds.
Both the Arctic and the South Pole experience polar day and polar night, either in daylight for a long time, or in the dark for a long time. Arctic terns migrate tens of thousands of kilometers a year, and when night comes, they fly to the other side of the globe in search of light. So, to us, arctic terns always seem to be chasing the light. That's why we call it the "Day bird."