Evaluating the influence of diet‐related variables on breeding performance and home range behaviour of a top predator

Abstract

A. Literature review of studies published in international scientific journals reporting factors influencing breeding success and home range behaviour in birds of prey MethodologyWe searched for scientific articles using the databases: Zoological Record (thomsonreuters.com/zoologicalrecord); Scopus (www.scopus.com); Google Scholar (scholar.google.com); JSTOR (www.jstor.org); SORA (sora.unm.edu). We used several combinations of the following search terms: breeding; reproduction; reproductive; success; output; performance; home range; movement; radio-tracking; telemetry; raptors; birds of prey; owls; eagle; kite; kestrel; vulture; buzzard; hawk; harrier; falcon. In addition, we inspected the references of each article analysed to gather other relevant studies. Since the number of results in each search was often very large (generally > 1000 results) we limited our database to the first 250 scientific articles we could access (see references below). In each study we verified: (1) the group of parameters (breeding performance; home range behaviour; or both); (2) the effects tested (see Table S1 for the list of the most common effects); (3) the number of effects considered; (4) the diet-related variables used; (5) the home range parameters analysed. ResultsMost articles only studied one species (92 %; n = 231), while the remaining included between 2 and 4 species.We included 79 articles focusing owl species only (32 %), 166 focusing on diurnal raptors only (66 %), and 5 focusing species from both groups (2 %). This review covered 49 species (15 owl species and 34 diurnal raptor species). Each species was included in 1 to 21 studies (mean ± SD = 5.8 ± 5.6).We found disproportionally more articles analysing the effects on breeding performance only (86 %; n = 215) than analysing the effects on home range behaviour only (12 %; n = 30), while just 5 studies (2 %) analysed jointly the effects on breeding performance and home range behaviour. The mean number of radio-1

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