Caracals on the edge of urban development
Tuesday, 17th August 2021
Hiding in plain sight: risk mitigation by a cryptic carnivore foraging at the urban edge.
Leighton, G. R., Bishop, J. M. Merondun, J., Winterton, D. J., O’Riain, M. J., & Serieys, L. E.
As natural habitat is progressively transformed, effective wildlife conservation relies on understanding the phenotypic traits that allow select species to persist outside of protected areas. Through behavioural flexibility such species may trade off abundant resources with risks, both real and perceived. As highly adaptable mesocarnivores, caracals (Caracal caracal) provide an opportunity to examine development of successful foraging strategies in high-risk developed areas. Here we investigated caracal resource selection of both anthropogenic and environmental factors relative to availability at varying levels of urbanization in and around the city of Cape Town, South Africa, using GPS cluster-located feeding events (n = 326 prey remains, n = 384 scat). We also examined spatial and temporal risk mitigation strategies by assessing behaviours at feeding clusters. We find that, within home ranges, caracals living in the urban-dominated region (n = 14; 548 feeding events) select for the urban edge, while caracals in the wildland-dominated region (n = 3; 162 feeding events) avoid it. Adults selected more strongly for foraging at the urban edge than juveniles and may competitively exclude them from resources. By including back-traced scat feeding event locations, we were able to improve model resolution. We argue that caracals foraging on the edge of a large metropole mitigate risk of detection by remaining cryptic, prolonging handling time, and maintaining high feeding site fidelity where cover was available. Along with the strong functional response to the urban edge, this strategy suggests that carnivores are being drawn into, and stay longer in, areas with potentially increased prey availability despite higher risk. While behavioural plasticity clearly enables carnivore coexistence with humans in urban ecosystems, it can also be maladaptive if it reduces fitness and leads the population into an ecological trap. We provide mitigative recommendations to promote the conservation of this predator in a spatially isolated and rapidly urbanizing landscape.