4.1 Influence of environmental variables on grey wolf and golden jackal potential distribution
Ensemble habitat suitability for both species revealed that large parts of the landscape were predicted as potentially suitable habitats for both species. Also, considerable proportions of key core habitats were concentrated in southern parts of the landscape. However, the connectivity modeling results revealed that these extended networks of core habitat areas were well connected by robust and strong movement corridors.
Distance to agricultural lands and topographic roughness were the most important explanatory variables out of those tested in predicting the occurrence of both canid species. Both species showed similar responses to these variables. The probability of golden jackal and grey wolf occurrence increased with increasing distance from agricultural lands and decreased with growing roughness. Our findings were similar to those of Shahnaseri et al. (2019) who showed that distance from agricultural lands was one of the most important variables affecting the presence of grey wolves and golden jackal in central Iran (Isfahan province). Heterogeneous agricultural lands which are structurally highly diverse provide a suitable habitat for many small wild preys (Alain, Gilles, & Yannick, 2006), i.e., an important potential prey for the golden jackal (Hayward et al., 2017; Lanszki, Kurys, Heltai, Csányi, & Ács, 2015; Shahnaseri et al., 2019; Torretta et al., 2020). Our results, however, show a negative association with agricultural lands suggesting that both grey wolf and jackal avoid agriculture lands or are persecuted by humans.
Golden jackal is highly adapted to live in human-dominated landscapes where they take advantage of various anthropogenic resources (Ćirović, Penezić, & Krofel, 2016; Lanszki, Schally, Heltai, & Ranc, 2018; Torretta et al., 2020). Our result showed that the occurrence of this species would reduce by increasing distance from dumpsites. Our results show that the southeastern parts of the region contain more suitable habitats for jackals and most road mortalities were recorded in the south parts of the study area. This could be due to the greater traffic volume on the south highways and to the high concentration of villages and rural areas in the south parts resulting in increased food resource availability such as dumpsites (Mohammadi et al., 2018; Tourani, Moqanaki, & Kiabi, 2012). The jackal is known as an elusive species that is timid around humans thus the species is primarily nocturnal and under high risk of vehicle collisions at night (Tóth, Krecsák, Szͩcs, Heltai, & Huszár, 2009). In order to mitigate the risk of jackal-vehicle collisions that are likely to increase during the summer tourist season, fencing and wildlife underpasses are proposed to be incorporated into road network plans and upgrades in areas with known jackal presence (Foster & Humphrey, 1995; Litvaitis & Tash, 2008).
In contrast to golden jackal, the distribution of the grey wolf was predominantly influenced by non-human related factors (e.g., elevation and roughness), a finding reported for other carnivore species in Iran (Ahmadi et al., 2017; Khosravi et al., 2018). The results of our model suggested that with growing distance to road wolf presence increased (Houle, Fortin, Dussault, Courtois, & Ouellet, 2010; Kabir et al., 2017; Kojola et al., 2016; Whittington, St. Clair, & Mercer, 2005). This finding suggested that wolves may seek to minimize the probability of encountering humans by selecting higher elevation and rougher topography farther from roads (Kabir et al., 2017). Our results in this regard are similar to Ahmadi et al. (2017) who showed that wolf den areas were characterized by the low density of settlements and primary roads. Furthermore, their result showed that wolves primarily establish dens in the sides of elevated steep-slope hills. Our results also revealed that elevation and roughness were important predictors of wolf presence.