Birds can read Earth’s ‘magnetic signature’ enough to get back on course

Birdwatchers are thrilled when a ‘rare’ migratory bird comes to land blown off course and flies past its normal range. But these are rare for a reason; most of the birds that made the previous trip are able to correct for large establishments and find their final destination.

Now, new research by an international team is showing for the first time, how birds that are moved in this way can move back to their migratory route and give us a glimpse of how to accomplish this task.

Writing in Conventional biology, the team from Bangor and Keele Universities describe how bamboo fuels can move from a ‘magnetic position’ beyond what they have experienced in their normal migration path, back towards the -this way right.

Different parts of the Earth have a specific ‘geomagnetic signature’ depending on where they are. This is a combination of the strength of the geomagnetic field, the magnetic inclination or dip angle between magnetic field lines and the magnetic field and illumination, or the angle between directions to geographic and magnetic North poles.

Adult birds already familiar with their route of migration, and its common magnetic names, were held captive for a short time before being released into the country, and were exposed to a symbol of the earth’s magnetic sign in a place thousands of miles past the birds. natural migration corridor.

Despite being physically positioned at their capture site and experiencing all other sensory sensations about their place, including starlight and sights, smells and sounds of the place itself , the birds were still encouraged to start the journey as if they were in the place suggested by the magnetic signal they were experiencing.

They directed themselves to fly in a direction that would take them ‘back’ to their migration path from the place suggested to them by the magnetic signals they were experiencing.

This shows that the magnetic field of the earth is the main feature in the direction of reed strings when they are blown off course.

“The real motivation was to respond to the magnetic information they were receiving,” explained Richard Holland from Bangor University’s School of Natural Sciences.

What our current work shows is that birds are able to sense that they are beyond the limits of the magnetic fields they are familiar with from their movements throughout the year, and are able to position them. have put enough out of the signals. This amazing ability enables a bird to move towards their normal migration path. “

Dr Dmitry Kishkinev from Keele University’s School of Life Sciences explained:

“What these birds are accomplishing is’ ‘real navigation’. In other words, they will be able to return to a known goal after being moved to a completely unknown place without being depending on the familiar environment, destination issues, or information gathered during the outing. ”

Florian Packmor from Bangor University said: “We have already shown that bamboo collectors use the same magnetic blocks experienced within their natural range, but this study is show that they can understand their understanding of how the magnetic field changes in a space far beyond any previous one. experience gained. “

But there are still questions as to whether the birds have a correct ‘map’ or whether they are just using the ‘rule of thumb’ measurement to judge the travel path needed to get back on the ground. course.

Eurasian bamboo mist was selected for the research, but the findings could be applied to other migratory songbirds.

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