Overlap and Segregation among Multiple 3D Home Ranges: A Non-Pairwise Metric with Demonstrative Application to the Lesser Kestrel Falco naumanni

• Published in: Biology (Basel, Switzerland) Switzerland), 2023-01, Vol.12 (1), p.77
• Main Authors: Ferrarini, Alessandro, Giglio, Giuseppe, Pellegrino, Stefania Caterina, Gustin, Marco
• Format: Article
• Language: English
• Subjects: 3D home range; 3D overlap/segregation estimator; animal space overlap; animal space use; Animals; Biodiversity; biotelemetry; Birds; Competition; Falco naumanni; Habitat selection; height above ground level; Home range; Predator-prey interactions; Prey; Topography
• ISSN: 2079-7737; 2079-7737
• DOI: 10.3390/biology12010077

In this study we solved the issue of measuring the degree of overlap/segregation among an arbitrarily large number ( ≥ 2) of 3D volumetric home ranges (i.e., , , and ; where is height above ground level) for the first time. For this purpose, we introduced the novel non-pairwise index (Multiple Volumetric Overlap Index) and its complement to 100 (Multiple Volumetric Segregation Index). Regardless of the number of 3D volumetric home ranges, the and generate a single score of overlap/segregation between 0 and 100, making ecological interpretation much easier and more meaningful when compared to × pairwise overlap indices. As a case study, we applied the and to 12,081 GPS points of five lesser kestrels ( ) during the nesting period at Santeramo in Colle (Apulia region; Italy) in an area with the most elevated density of lesser kestrels in urban colonies worldwide. The 3D volumetric home ranges ranged between 1.79 km and 8.19 km . We found that the tracked birds had different vertical profiles, possibly to limit intraspecific competition, resulting in a 3D home range overlap that was only 61.1% of the 2D overlap and 52.8% of the probabilistic one.