Interactions between carnivore species: limited spatiotemporal partitioning between apex predator and smaller carnivores in a Mediterranean protected area

Abstract

Background There is need of information on ecological interactions that keystone species such as apex predators establish in ecosystems recently recolonised. Interactions among carnivore species have the potential to influence community-level processes, with consequences for ecosystem dynamics. Although avoidance of apex predators by smaller carnivores has been reported, there is increasing evidence that the potential for competitive-to-facilitative interactions is context-dependent. In a protected area recently recolonised by the wolf Canis lupus and hosting abundant wild prey (3 ungulate species, 20–30 individuals/km2, together), we used 5-year food habit analyses and 3-year camera trapping to (i) investigate the role of mesocarnivores (4 species) in the wolf diet; (ii) test for temporal, spatial, and fine-scale spatiotemporal association between mesocarnivores and the wolf. Results Wolf diet was dominated by large herbivores (86% occurrences, N = 2201 scats), with mesocarnivores occurring in 2% scats. We collected 12,808 carnivore detections over > 19,000 camera trapping days. We found substantial (i.e., generally ≥ 0.75, 0–1 scale) temporal overlap between mesocarnivores—in particular red fox—and the wolf, with no support for negative temporal or spatial associations between mesocarnivore and wolf detection rates. All the species were nocturnal/crepuscular and results suggested a minor role of human activity in modifying interspecific spatiotemporal partitioning. Conclusions Results suggest that the local great availability of large prey to wolves limited negative interactions towards smaller carnivores, thus reducing the potential for spatiotemporal avoidance. Our study emphasises that avoidance patterns leading to substantial spatiotemporal partitioning are not ubiquitous in carnivore guilds.

Spatio-temporal interactions between the red fox and the wolf in two contrasting European landscapes

“…1 S). Our results for Maremma RP confirm previous observations that foxes show a remarkable temporal overlap with the wolf 17 , 32 , with a greater synchronisation at sites more used by wolves than at sites less used by this apex predator 25 . Our Białowieża PF findings agree with results obtained by Haswell et al 12 in another European area hosting the same carnivore community (Plitivice Lakes National Park, Croatia).…”

“…Our Białowieża PF findings agree with results obtained by Haswell et al 12 in another European area hosting the same carnivore community (Plitivice Lakes National Park, Croatia). Furthermore, at neither of our study areas did we find a negative spatial association between fox and wolf activity (see also 32 ), at either the coarser or finer temporal scale. In contrast, we found a positive spatial association of the activity of the two carnivores, especially at the fine (daily) time scale.…”

“…a century of absence 17 . During our study 2–3 wolf packs were reported 32 Around 20–30 wild ungulates/km 2 were estimated in summer (i.e., wild boar Sus scrofa : 10.5–15.1 individuals/km 2 ; fallow deer Dama dama : 8.3–9.1 individuals/km 2 ; roe deer Capreolus capreolus : 3.1–6.9 individuals/km 2 ), on the last decade 30 , 33 , 34 .The Park Agency manages populations of fallow deer and wild boar through culling (both species) and trapping (wild boar), to limit the negative impacts of these ungulates on habitats/species with conservation relevance, and on agriculture. Livestock ( c. 20 heads/km 2 ) is also present, including free-ranging cattle and horses, as well as two sheep herds in sectors more marginal to the boundary to the Park 30 .…”

“…Moreover, compared to many boreal ecosystems, Maremma RP and Białowieża PF, host relatively high ungulate densities (respectively 20–30 ungulates/km 2 and 14 ungulates/km 2 ), which could explain the rather subtle differences we found in wolf-fox interactions between both areas. In our study areas, wolf food habits have been shown to be dominated by large, wild prey (Białowieża PF: 68 ; Maremma RP: 17 , 30 , 32 , while foxes are significant scavengers of wolf kills (Białowieża PF: 23 ; Maremma RP: 17 . A concurrent study in Maremma reported a three-to-fourfold increase in the occurrence of ungulates in the fox diet with respect to times when the wolf did not present in the area 17 ; (see also 69 , for fox-Eurasian lynx interactions): this may be evidence for trophic facilitation mediated-by an increase of foraging opportunities provided through leftovers.…”

“…A concurrent study in Maremma reported a three-to-fourfold increase in the occurrence of ungulates in the fox diet with respect to times when the wolf did not present in the area 17 ; (see also 69 , for fox-Eurasian lynx interactions): this may be evidence for trophic facilitation mediated-by an increase of foraging opportunities provided through leftovers. Furthermore, a study based of 3 whole-year data found no support for spatio-temporal avoidance 32 . Our results suggest that wolf movements might influence those of red foxes, possibly indicating a predominance of the attractive component, at least at the scales we analysed.…”