The bird misdirected itself when the magnetic field was disturbed

Migratory birds and the pensioners have gone south again for the winter. Life is sunny when you can float in eternal summer.

But how do birds always know how to return to the same place from thousands of kilometers away?

This was a mystery for a long time, like migratory birds in general. Aristotle among other things, he showed that birds that disappear from view in winter either hibernate or change into completely different species. Alder birds would become red-breasted in winter and so on.

Today it is known that birds sense the Earth’s magnetic field and know how to navigate using it. They also make use of the sun and stars. But from the magnetic field, the bird knows exactly which way is north and which is south.

In addition to an internal compass, the bird also has a map, namely the magnetic field tells it where in the world it is right now. The researchers demonstrate this in a newly published study in the article.

Rytikerttunen (Acrocephalus scirpaceus) is a small brown sparrow bird. It is not related to the former president, but Ryti means lake reed, which the bird lives in reed beds.

The researchers caught 21 gerbils on their way to Africa in Austria and conducted a clever experiment on them.

The birds were put in a large cage, or aviary, where an artificial magnetic field was created.

The researchers tweaked the magnetic field parameters so that the field was similar to the one in Neftekamsk, Russia, 2,700 kilometers to the northeast. It is well out of the way of the birds.

When we then looked at which direction the birds tried to go, they wanted to go southwest, i.e. back to their route. The birds really thought they were far to the east based on the magnetic field.

If the birds’ navigators were not disturbed, they wanted to go south, where they were going in the first place.

Birds magnetic sense is likely based on proteins in their eyes that react quantum chemically to magnetic fields. Maybe they “see” magnetic fields in some way.

The test did not mess up the birds’ internal compass for good. At least one of the birds flew into the hands of researchers again on its migration the following year.