SEEN - SE European Bird Migration Network
Moonwatching: Nocturnal bird migration across the Eastern Alps, Austria

Martin Rössler, Christoph Schauer

Nocturnal Migration Network Eastern Alps, SEEN Member Station Hohenau – Ringelsdorf, Austria

Little is known about the nocturnal passage of migrating birds across Austria. To provide some basic information about this phenomenon, simultaneous observations of bird movements in front of the moon were organized in spring and autumn 2005. The Nocturnal Migration Network Eastern Alps comprised 95 observers at 60 sites. Observations were made over six full moon periods (in March, April, May, August, September and October) and yielded provisional patterns of flight directions. The results indicate a major flow of birds across the Eastern Alpine mountainous area which seems to take no account of topographical features. To the north of the Alps, a significant portion of the flight directions observed correspond to the east–west orientation of the topography. Under certain circumstances, such as atmospheric inversion, flight levels were found to be well above the mountain ridges. In August, south-easterly movements were detected, although a significant proportion of these were restricted to the easternmost observation sites. Although these preliminary results are thought-provoking, the limitations of the method – distance estimation, altitude specification, significance of the moon elevation etc. – need careful consideration.

Created by Pronetix 2006