When temperatures drop, around 200 European bird species head south. Around 50 billion migratory birds can be seen in the sky in the autumn, and thousands of kilometers can often be found on the way to their winter quarters. The following spring, the commuters begin their exhausting return journey to the north. Staying in the always warm south does not seem to be an option for the animals despite the life-threatening journey.
No wonder, because in the summer months local birds find the best conditions in Germany, as bird expert Eric Neuling from the German Nature Conservation Union (Nabu) explains: “The north offers the birds a lot of food in the summer months and optimal conditions for raising the young. ” In winter, the conditions are not so good. Because when there is snow and the ground is frozen, the food supply is limited. The south has more to offer then.
Announces in the south, however, a few months later, the summer, the tide turns again: The living conditions for cranes, storks and Co. are no longer optimal in southern Europe and Africa. It gets hot and dry, the food supply shrinks. The struggle for survival is intensifying. The bird guests must increasingly compete with the native bird species for food and habitat. So the animal guests finally return to the north.
Train behavior changes
However, new studies show that climate change changes the behavior of trains. So-called short-range voyages, such as crane, lapwing or song thrush shorten their train paths due to the increasing mild winter. Many migratory birds return from their winter quarters about three weeks earlier than they did 40 years ago. Some species change their departure times in autumn, which partially extends the length of stay in the home. Even the brood starts earlier and earlier. The Nabu expert explained: First, the early homecoming is due to the rising temperatures in Africa and the breeding area, on the other hand, the waning rain at the important rest areas on the Mediterranean coast. Many birds would just rest briefly and then continue north fast.
Meanwhile, there are also bird species that do not move south due to the mild winter. “Birds are not as fun as we are, some species even avoid the long journey,” says bird expert novice. “The star, for example, is such a part-puller, who adapts his train behavior to the circumstances,” says newcomer. Some star populations do not fly south in the winter, but instead move to our cities: there is enough food and enough shelter.