A new methodology for computing birds’ 3D home ranges

Abstract

Abstract Background So far, studies of avian space use are mostly realized in 2D, with the vertical dimension ignored. We propose here a new, relatively simple and computationally reasonable method for the estimation of volumetric (i.e. 3D) avian home ranges. Methods Through accurate GPS data-loggers, we collected 25,405 GPS points on Lesser Kestrels’ (Falco naumanni) space use during the nestling period in one main colony in Italy. We applied our 3D home range estimator to the whole GPS dataset, and also separately to diurnal and nocturnal GPS points. Results The 3D colony home range resulted equal to 28.12 km3. By considering daytime and night-time separately, the volumetric home ranges resulted considerably different. Conclusions Our 3D home range estimator, because of its intuitive and straightforward properties, can easily capitalize on the datasets offered by modern biotelemetry (data-loggers, light detection and LIDAR sensors) and enhance conservation strategies for mitigating anthropogenic impacts on bird species. Its applications embrace, but are not limited to, more accurate estimates of collision risk with power lines, aircrafts and wind farms, and increased knowledge of birds’ space requirements in order to persist in their distribution areas.

Keywords

• Avian space use
• Biotelemetry
• GPS data-loggers
• Vertical dimension
• Volumetric home range