Beyond ungulate density: Prey switching and selection by the wolf in a recolonised area

The analysis of mechanisms underlying prey use and selection is crucial for understanding the potential for apex predators to shape ecological processes across trophic levels. Significant implications for the conservation and management of ecosystems can ensue, especially in human-modified landscape...

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Bibliographic Details
Published in:Global Ecology and Conservation
Main Authors: Lorenzo Lazzeri, Irene Belardi, Giada Pacini, Niccolò Fattorini, Francesco Ferretti
Format: Article in Journal/Newspaper
Language:English
Published: Elsevier 2024
Subjects:
Online Access:https://doi.org/10.1016/j.gecco.2024.e03069
https://doaj.org/article/3b8aecdc00c143aeba3fb7bad57dc340
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Summary:The analysis of mechanisms underlying prey use and selection is crucial for understanding the potential for apex predators to shape ecological processes across trophic levels. Significant implications for the conservation and management of ecosystems can ensue, especially in human-modified landscapes characterised by the recent recovery of apex predators, such as those of Europe. Generalist predators may show frequency-dependent prey selection, leading to prey switching; however, there is no ubiquitous support for positive relationships between prey abundance and prey selection. In a protected area recently recolonised by the wolf Canis lupus and hosting abundant wild prey (>20 individuals/km2), we assessed prey use and selection (>3000 wolf scats analysed) throughout 7 years since wolf settlement (April 2016-to-March 2023), during which prey density was relatively stable. Wolf diet was dominated by wild boar Sus scrofa and fallow deer Dama dama (>70 % of occurrences and volume); the roe deer Capreolus capreolus and coypu Myocastor coypus represented main secondary prey. The wolf showed a clear prey switching throughout the study. In the first two years, the fallow deer was the main prey and was positively selected. Then, wild boar replaced fallow deer as main prey, and was positively selected, with a progressive decrease in the use of fallow deer throughout the years. Selection indices of wild boar were negatively associated with those of fallow deer. The relationship between selection indices and population density was inconsistent across species, being negative for the wild boar and weakly positive for the fallow deer, although the latter showed no sharp decline in the area. Concurrent studies showed increased diurnal activity of fallow deer and a consequent reduced temporal overlap with the wolf throughout years since the settlement of this predator, suggesting temporal avoidance. By supporting a minor role of prey density in mediating prey switching, our results suggest a major role of other ...