It was long thought that they found their way through the Earth’s magnetic field.They can observe them. However, no concrete evidence could be found.
There were anecdotes about pigeons that kept wandering around after their habitat disappeared (for example, by new buildings on their original habitat), but still not really concrete dates.Dr. Anna Gagliano of the University of Pisa has done a lot of research here, and in 2001 she (A.O.) found out that pigeons could use landmarks such as buildings in the final stage of their trip, but they also used their nose. [1
Here she took a look at a number of follow-up studies.In one of these, she excluded the magnetic field theory by turning off the part of the brain that perceives this field in one test group of pigeons. In Another group she switched off the sense of smell, and in addition there was a control group. She followed these pigeons with GPS-zendertjes. The pigeons that could no longer observe the magnetic field, all found their way back, one after the other. The pigeons that had lost their sense of smell became stray. [2 [ 3 [4
Apparently they make a ‘ card ‘ of smells in their surroundings, and they are looking at this specific fragrance print when they fly home.In addition, Gagliano also found that pigeons could learn to navigate through the stand of the Sun to win a candy, so they can also use this solar compass in their navigation. [5 their sense of smell seems to be the most important factor, because they do not touch them all the way, which is not the case with their other abilities.
However, these studies are mainly conducted over shorter distances than 1000 kilometers, and the pigeon racing are usually somewhere between 100 and 1000 kilometers, so who knows they use other techniques at the beginning of their journey than at the end.Anyway, they are remarkable animals.