Prey selection and dietary response by wolves in a high-density multi-species ungulate community

Abstract

Studies on predation by the wolf (Canis lupus) have often reported contradictory results about the role of prey density and vulnerability on wolf prey use. We investigated dietary response and prey selection by wolves in a high-density and multi-species ungulate community, analysing scats collected over a period of 11 years in the Casentinesi Forests, Italy. The second most abundant species, wild boar (Sus scrofa), was found to be the main wolf prey, and we did not observe any dietary response of wolves to variations in the density of either primary or secondary prey species. Selection patterns were uniform throughout the study period. Wolves strongly selected for wild boar piglets, while roe deer (Capreolus capreolus) fawns and adults, red deer (Cervus elaphus) adults and fallow deer (Dama dama) adults were avoided. Wolf preference for wild boar was inversely density dependent. Within each species, juveniles were preferred to adults. Medium-sized, young individuals of both wild boar and roe deer were optimal prey, although with different selection patterns related to the different anti-predator strategies adopted by each prey species. The results of this study suggest that in productive ecosystems with high density and high renewal rates of prey, selection patterns by wolves are determined by prey vulnerability, which is connected to prey age and body size. The different patterns of wild boar versus cervids use by wolf across Europe seems to be related to their relative abundances, while the strong selection of wild boar in Italian Apennines with respect to the more frequent avoidance in central-eastern Europe is better explained by higher piglet productivity and smaller body size of adults boar in Mediterranean temperate forests.

Winter severity or supplementary feeding—which matters more for wild boar?

“…Similarly, in Poland, mortality from causes other than predation prevails in populations of wild boar, whether or not predators are present (Jędrzejewski et al 1992). Wolves may exert a heavier predation impact in warmer, more productive ecosystems (Melis et al 2006;Cutini et al 2013), where wild boar is the main prey species (Mattioli et al 2011), but also, natural predation might not play an important role where predator populations are intensively managed.…”

Wolf diet in an agricultural landscape of north-eastern Turkey

“…Brought to you by | Utah State University Authenticated Download Date | 2/6/18 10:56 PM other studies (Rigg and Gorman 2004, Tumanov 1998, Van Duyne et al 2009, Mattioli et al 2011; Table 1). …”

“…We calculated the biomass using the prey weights reported in Prey abundance is quantified by MPV, FO and biomass share (BM) according to Floyd et al 1978. a Mean weight of wild boar was estimated accounting for the weight classes identified in the scats, following Mattioli et al (2011). Mean weights of prey (PW) followed previous studies: b Rigg and Gorman (2004) The Brillouin diversity index (Hb) mean and 95% confidence intervals (CI) and incremental change curves.…”

Genome-wide signatures of population bottlenecks and diversifying selection in European wolves

“…Smaller body size in grey wolves may have a selective advantage in habitats with smaller prey (MacNulty et al, 2009), and the three European populations occupy distinct habitats that differ in species composition and the relative abundance of ungulate prey. Smaller species like the roe deer (Capreolus capreolus) and the wild boar (Sus scrofa) are common in the wolf diet in the Iberian Peninsula and Italy (for example, Barja, 2009;Mattioli et al, 2011), whereas larger prey such as the red deer (Cervus elaphus) and moose (Alces alces) are more frequent in the wolf diet of northeastern Europe .…”