Agriculture is the main cause of bird deaths in Europe
The population of many birds has been dwindling for years, not only in Germany. A study is now showing the causes of the decline and which species are particularly affected. But some were able to gain – and play off others.
Dhe number of birds in Europe fell by around a quarter from 1980 to 2016. The main reason for this is one current study According to the journal “PNAS”, intensive agriculture. Accordingly, increasing urbanization and rising temperatures also play an important role. birds in fields were particularly affected. Nevertheless, according to the researchers around Stanislas Rigal and Vincent Devictor from the Institut des Sciences de l’Evolution de Montpellier, there are also species among the feathered animals that benefit from the changed conditions.
“Declining European bird populations have been reported for decades,” the study authors write. “However, the direct effects of large man-made pressures on this decline have not yet been quantified.” For their study, they used observation data on 170 common bird species at more than 20,000 locations in 28 European countries. Second, they used statistics like those from the Statistical Office of the European Union and the Food and Agriculture Organization of the United Nations.
The decline in bird populations is therefore not evenly distributed. Species that prefer farmland for habitat, including partridge, skylark and lapwing, declined by almost 57 percent on average. This was particularly evident in the Western European industrialized countries, where intensive agriculture dominates. In Eastern Europe, where in many places farming has been done on a smaller scale and less intensively, the decline has not been so clear.
Of the birds that depend on cooler areas, 40 percent disappeared; of those in the cities, it was just under 28 percent. The populations that inhabit warmer habitats and forests shrank less sharply, by a good 17 percent.
The authors write that intensive farming, with its heavy use of pesticides and fertilizers, is the main cause of bird deaths. In particular, the pesticides killed insects, which in turn serve as food for many species. The researchers conclude that the figures show that if the type of agriculture does not change, the “fate of European bird populations” is at stake.
For Christian Hof, research group leader at the Chair of Terrestrial Ecology at the Technical University of Munich, these findings are not surprising. However, they used extensive data to make the connection between the loss of birds and the intensity of agriculture and other factors particularly clear. In the fields, however, not only pesticides and fertilizers are responsible for dying.
Structures in the landscape such as hedges and trees are also crucial. For the animals and the groundwater, it would be “of course gratifying” if there were more organic farming, says Hof. But it is not “automatically better” because it needs more space for the same yield. “However, less intensive agriculture is indicated for many reasons.”
According to Hof, not only the cold-loving species are suffering from climate change, but also the migratory birds. He explains: “Birds that winter in southern Africa don’t realize when spring conditions in Europe are already good enough to breed.” The animals that wintered in Europe noted: “The leaves in the forest are budding , the caterpillars are there, I can breed”. Species such as the pied flycatcher, the collared flycatcher or the cuckoo would then return too late from their winter quarters. All nesting sites are then already occupied, the caterpillars have already eaten as food for rearing their young.
Despite the setbacks in most species, some have made gains in recent years. bee-eaters, short-toed treecreepers, collared pigeons and other thermophilic species benefited from rising temperatures. According to Hof, if these migrated to certain areas, they could reproduce there better than those that preferred cold.
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