Algemeen

Auf Einladung des Bund für Umwelt und Naturschutz Deutschland (BUND) referierte der Insektenforscher Thomas Hörren vom Entomologischen Verein Krefeld (EVK) im Möllner Quellenhof vor 90 Besuchern über deren bahnbrechende Studie zum Thema “Rückgang der Insekten-Biodiversität”. An zahlreichen Standorten ausschließlich in Schutzgebieten hatte der EVK 27 Jahre lang die Insektenfauna untersucht. Aufgrund des enormer Datenbestand und der wissenschaftlichen Methodik waren die Entomologen in der Lage, nicht nur den schleichenden Verlust an Arten, sondern auch an Insekten-Biomasse zu dokumentieren.

A sharp decline in migratory bird populations has flummoxed ecologists trying to pinpoint the risks faced by these birds. New Cornell research points to a possible explanation for declines: the connection between aquatic insect prey and bird reproductive performance.

Between our paved backyards and potted plants, our drained wetlands and vast areas of monoculture – there is silence. Nearly six decades since Rachel Carson’s book Silent Spring exposed the devastating effects of DDT on humans and wildlife, bird populations around the world are plummeting. Birds of all kinds are vanishing as a result of human impact on the environment:

Since European settlement, over 100 species have been lost here. These include plants and animals that are extinct and extirpated, and species that are considered historic (no one has seen them in Canada for a long time). The number of lost species varies between different regions of the country. In the Great Lakes region of southern Ontario, there are extinct species (passenger pigeon), extirpated species (paddlefish) and historic species (Eskimo curlew). There are also species that have vanished from this landscape but still exist elsewhere in Canada.

Nineteenth-century poet John Clare wove together “descriptions of the environment and accounts of human life,” making no distinction between human and natural history. The anthropologists Richard D.G. Irvine and Mina Gorji argue that this makes him in some ways a poet of our current age, the Anthropocene. He drew connections between the reduction of insect life and the corresponding diminishment of the birds and mammals further up the food chain, essentially foretelling the dire environmental state we see today. Clare recognized an inherent value in land unconnected to human use.

Seven birds that were once considered common and widespread are now plummeting towards extinction. Some of the species on this list will shock you. The European Turtle-dove Streptopelia turtur is so familiar in Europe that it even features in the second verse of the wildly popular Christmas carol “The 12 Days of Christmas”. Imagine if we had to change the words of the song to reflect the loss of this much-loved species…

A while back we took note of a study that showed populations of airborne insects have declined by 76 percent in protected areas in Germany over the past 27 years. Part of the picture was that the disappearance of bugs is likely to pose problems for other animals in the food chain. Now a recent study by French scientists revealed that bird populations in France’s farming areas have declined by more than one-third in the past 17 years. Both resident and migrant species have decreased sharply.

One in eight bird species is threatened with global extinction, and once widespread creatures such as the puffin, snowy owl and turtle dove are plummeting towards oblivion, according to the definitive study of global bird populations. The State of the World’s Birds, a five-year compendium of population data from the best-studied group of animals on the planet, reveals a biodiversity crisis driven by the expansion and intensification of agriculture. In all, 74% of 1,469 globally threatened birds are affected primarily by farming.