Spatial Patterns of Bird Movements on and around an Airport, a Case Study on Eindhoven Airport - Extra Dimensions from the Panorama-scan

In commission of the Royal Netherlands Air Force and the City of Eindhoven we registered the number of birds aloft on Eindhoven Airport between August 1998 and July 1999 by visual techniques using binoculars. Observations were conducted during four days each month and lasted the full daylight period. Two methods were used: observations in a fixed volume covering a part of the runway and bordering fields (fixed volume count) and observations in a radarlike way covering a much larger volume consisting of the total airport and surrounding landscape (horizon-scan). The focus of this paper is on the second technique. Since the risk of bird strike is highest during take off and landing (i.e. the lower air layers), it is important to know the density and species composition of birds that are flying near and over runways. Questions from the perspective of bird strike risk and bird control are whether the numbers and species composition of birds flying over the runways show a relation with the surrounding landscape of the airport and whether bird flight routes occur in relation to landscape structures. Eindhoven Airport has an open landscape and is located in a forested area in the southeast of The Netherlands. As the panorama-scan covers a much wider area than the single runway of Eindhoven Airport (as in the case of the fixed volume scan) this visual technique gives the opportunity to compare and relate the numbers of birds aloft above as well as around the airport. In this paper we show that with this technique, besides reliable information on densities of birds aloft, at the same time detailed spatial and flight direction information is gathered which makes it