Researchers at the Max Planck Institute for Behavioral Biology have warned against dying birds in Germany and Europe. On Lake Constance alone, the number of pairs of birds has fallen by a quarter in the past 30 years, according to a study by scientists from the Institute's Ornithological Working Group. 980 lived in the region still about 465,000 breeding pairs, in 2012 only 345 000.
Once frequent bird species such as house sparrow, blackbird or star had fallen significantly, writes one of the authors of the study in the journal Vogelwelt . The development on Lake Constance reflects a Europe-wide downward trend.
Bird-hostile agricultural landscapes
In other regions of Germany, the numbers of many species collapsed, according to the scientists. However not everywhere as dramatically as on Lake Constance: "The western and southern regions are more affected than the eastern and northern," it continues. This is due to the more intensive agriculture in the south and west.
For the researchers today's agricultural landscapes are regarded as hostile territory. Many birds would find hardly any more habitats and breeding grounds on the intensively used areas. For example, the formerly widespread partridge around Lake Constance has become extinct. Even predatory shrikes, meadow pipits and little owls are no longer there today.
For the data collection, the scientists had counted all the birds on an area of around 1,100 square kilometers around Lake Constance. Previously, the ornithologists had recorded the stocks for the first time from 1980 to 1981 and then every ten years.
Species affected to different degrees
Also throughout Europe, the number of insect-living birds such as wagtail, meadow pipit or barn swallow has dropped significantly in the last 25 years. On average, the number of these birds dropped by 13 percent according to a study published in March in the journal Conservation Biology .
Data from the pan-European bird monitoring program PECBMS show that European herds of field and meadow birds in Europe have declined by 57 per cent since the beginning of census from 1980 to 2016; they include skylarks, lapwings or starlings. For the study, data from 28 countries on over 170 species were compiled. Fell far better than the field birds, the forest birds, whose inventory fell in the observed period, only six percent.
Also on Lake Constance species are affected differently depending on habitat, the current study shows. While 71 per cent of the species living in meadows and fields collapsed, 48 per cent of the species living in the forest rose, compared with 35 per cent. An example is the Great Spotted Woodpecker with an increase of 84 percent, which seems to benefit so far from the larger amounts of wood in the forests.