Patch characteristics and domestic dogs differentially affect carnivore space use in fragmented landscapes in southern Chile

Abstract

Aim: In an increasingly anthropogenic world, species face multiple interacting threats. Habitat fragmentation and domestic dogs are two perturbations threatening terrestrial mammals globally. Our aim was to determine whether (a) the spatial use of domestic dogs increases with habitat destruction, and (b) domestic dogs and habitat destruction drive the spatial use of native carnivores in a heavily degraded agricultural landscape. Location: Central valley/Andean foothills transition of Los Lagos, Chile. Methods: We implemented a camera trap survey in a fragmented landscape comprised of native forest patches amidst a matrix of pastureland. We used single-species occupancy models to assess the impact of domestic dogs and habitat destruction on three mesocarnivores—the foxes, culpeo (Lycalopex culpaeus) and chilla (Lycalopex griseus) and the wild cat güiña (Leopardus guigna). Additionally, we compared temporal activity of all study species including domestic dogs. Results: Detection rates for both the foxes increased with domestic dog occupancy, while factors driving occupancy differed for each of the native species. We found that a 12% projected increase in domestic dog occupancy negatively impacted the spatial use of the culpeo. Habitat loss and fragmentation were positive drivers for chilla and domestic dog occupancy. The güiña did not respond to fragmentation and other habitat covariates or domestic dog occupancy. All native carnivore species were primarily nocturnal, while the domestic dog was almost entirely diurnal. Main Conclusions: We highlight that domestic dog occupancy was positively correlated with habitat loss. Native species showed varied tolerance to domestic dog occupancy and no negative response to habitat destruction. Future conditions of increased fragmentation and habitat loss will likely increase the potential contact between domestic dogs and native carnivores.