Wiesenbewässerung in den Alpen und ihr Einfluss auf die Vogelwelt

Meadow irrigation in the Alps and its effects on the avifauna.- In many parts, populations of meadow-breeding birds have strongly decreased, also in the Central Alps. Intensification of agricultural practices has often been mentioned as primary cause for the decline. In areas with rather low precipitation in the Central Alps, irrigation can lead to intensification. Thus far, only a few studies have analysed the effect of irrigation on meadow-breeding birds. In this article, two studies are presented which focus on different aspects of this subject: Studies from the Engadin show that recent irrigation has in fact led to an intensified use of meadows, but that its impact on the vegetation has only fully become visible ten to twenty years after implementation of irrigation. Together with the installation of modern sprinklers, drastic changes in the avifauna were recorded between 1987/88 and 2009/10. Meadow-breeding birds displayed strong declines which were presumably in part caused by modern irrigation. Results from the Vinschgau (Tyrol) indicated that the type of irrigation – traditional irrigation with water channels versus modern irrigation with sprinklers – had no direct influence on breeding birds. However, there is a potential risk that a switch to modern irrigation techniques might lead to a general intensification of grassland use