Author: Jiansan (Hebei Huailai)
So far, there are still 15 swans roosting in my hometown, which is strange to say, and at this time of year, they have already flown north to reach their breeding place, but this year they are stunned!
The swan is a typical migratory bird, winter migratory bird to be precise. They fly north each spring, where they breed. In autumn and winter, when the young birds grow up, the weather gets colder in the north, and the swans migrate to the warmer south for the winter. We're just a short respite from the swans' migration.
Swans migrate not because they are afraid of the cold, but in search of food. The swan is an extremely hardy animal with a thick layer of fat on its body and a very fine and dense feather covering its surface that is very warm and waterproof.
In March last year, a strange incident occurred during the migration of swans wintering in Rongcheng, Shandong Province, when they left Rongcheng and flew north across the Bohai Bay to Dalian, Liaoning Province. Normally, the swans will stay there for a few days before continuing their migration north to reach their breeding grounds.
However, according to the tracker on the swan, experts found that one swan had stopped in Dalian for less than a day before turning south and flying back to Rongcheng again. At the same time, other swans returned to their starting point. Over the course of three days, the swans flew 600 kilometers and returned to their original point.
Experts say that the phenomenon of swans migrating north and returning soon is the first time it has been detected since the monitoring, and it has never been detected before. So why don't these swans continue their migration north, but turn back again?
In early March last year, the temperature in Liaoning was not high, and it even snowed in some places. Swans are sensitive to temperature changes, so instead of moving north, they choose to fly back to their original wintering habitats.
In addition, previous studies have shown that it is possible for birds to navigate with the help of the Earth's magnetic field. When scientists attach an artificial magnet to carrier pigeons, they lose their ability to discern direction and fly in the right direction.
The north and south poles of the Earth's magnetic field have flipped many times in the distant past. If the swans find a difference in the magnetic field, this may also cause them to turn back. But for now, the reason for the swans' migration and return is more likely to be a climate problem.
So why don't the 15 swans that stay with us fly north? The answer is: there are abundant water snails and aquatic plants here, and it is not worth it to give up such a good thing in front of you and fly more than 3,000 kilometers!
This is exactly what it is:
The world is changing fast, and the migration of swans is strange.
Rest the habitat on the way, and it's not bad to breed here!
It is our responsibility to protect these white swans, which are not only part of the natural ecology, but also part of our happy life.
2024.04.28
Editor: Li Xunxiu/Niu Yixin/Song Zhanlin Editorial Department of "Qingyanwei Literature".