Niche partitioning between sympatric wild canids: the case of the golden jackal (Canis aureus) and the red fox (Vulpes vulpes) in north-eastern Italy

Abstract

Background Two coexisting species with similar ecological requirements avoid or reduce competition by changing the extent of their use of a given resource. Numerous coexistence mechanisms have been proposed, but species interactions can also be aggressive; thus, generally a subordinate species modifies its realized niche to limit the probability of direct encounters with the dominant species. We studied niche partitioning between two sympatric wild canids in north-eastern Italy: the golden jackal and the red fox, which, based on competition theories, have a high potential for competition. We considered four main niche dimensions: space, habitat, time, and diet. Results We investigated three study areas monitoring target species populations from March 2017 to November 2018 using non-invasive monitoring techniques. Red fox presence was ascertained in every study area, while golden jackal presence was not ascertained in one study area, where we collected data regarding wolf presence. Considering the two target species, we observed partial diet partitioning based on prey size, with the golden jackal mainly feeding on wild ungulates and the red fox mainly feeding on small mammals. The two canids had an extensive temporal overlap along the diel cycle, having both predominant crepuscular and nocturnal activity patterns, but marked spatial partitioning and differential use of habitats. The golden jackal proved to be specialist concerning the habitat dimension, while the red fox resulted completely generalist: the former selected less human-modified habitats and avoided intensively cultivated lands, while the latter was present in all habitats, including intensively cultivated lands. Conclusions The observed partitioning might be due partially to some ecological adaptations (e.g. specialist vs. generalist use of resources) and specific behaviours (e.g. cooperative vs. solitary hunting) and partially to the avoidance response of the red fox aimed at reducing the probability of direct encounters with the golden jackal.

Wolf Is Back: A Novel Sensitive Sentinel Rejoins the Trichinella Cycle in the Western Alps

“…One opinion is that, in order to persist endemically, T. britovi (and any other sylvatic Trichinella taxon) requires an ecological chain composed of multiple interrelated carnivore hosts [ 59 ]. Under these circumstances, the enrichment of the carnivore community with an apex predator (e.g., the return of the wolf to the Alps) has the potential to generate new intraguild interactions [ 60 , 61 , 62 , 63 ] and new opportunities of cannibalism and interspecific scavenging and predation [ 64 , 65 ], eventually resulting in higher Trichinella prevalence and larval biomass, as occurred in Finland following colonization by another canid, the not native raccoon dog ( Nyctereutes procyonoides ) [ 35 ]. A second hypothesis is that foxes, the most investigated Trichinella host, would be capable to sustain the circulation of T. britovi independently of the presence of other infected carnivores, mainly through cannibalism, also referred as intraspecific scavenging [ 52 ].…”

From the Balkan towards Western Europe: Range expansion of the golden jackal (Canis aureus)—A climatic niche modeling approach

“…Besides, interspecific competition is considered a key factor shaping the distribution patterns of species (Pacifici et al, 2020 ). Competing species with similar ecological requirements that are sympatrically distributed, may coexist or mutually exclude each other, depending on the availability of resources (Torretta et al, 2021 ). The presence of the gray wolf ( Canis lupus ) is considered to be an important limiting factor for the distribution of the golden jackal, as wolf occurrences can prevent the establishment of the golden jackal (Krofel et al, 2017 ).…”

“…The golden jackal is a medium‐sized opportunistic mesopredator with a broad range of food categories, including small mammals (mainly rodents), birds (and their eggs), amphibians, reptiles, invertebrates, and sporadically plants (especially fruits) (Farkas et al, 2017 ; Gherman & Mihalca, 2017 ; Lange et al, 2021 ; Lanszki et al, 2016 ; Penezić & Ćirović, 2015 ; Torretta et al, 2021 ). This flexible and generalist diet of the golden jackal is supposed to promote the currently observed area expansion (Hatlauf et al, 2021 ).…”

Micro-Epidemiological Investigation of Echinococcus multilocularis in Wild Hosts from an Endemic Area of Southwestern Hungary

“…The presence of interspecific competition between foxes and jackals could also support the formation of the clusters. Among predators, competitive interactions can affect the utilization of resources and modify the populations' success [18,19]. The presence of an apex predator eventuates spatial and/or temporal avoiding behavior in mesopredators.…”