Environmental Studies Program



Adam Carlson

Date of this Version



Environmental Studies Undergraduate Student Thesis, University of Nebraska-Lincoln, 2023


Copyright 2023, Adam Carlson


Wildlife species that share a landscape may vary their use of time, space, and resources, thereby enabling sympatry between species. Interspecific relationships among sympatric canids are often inferred through temporal and spatial activity patterns. Body size is an important influence on interspecific relationships, as it affects competition, access to prey, resources, and vulnerability to predation. Coyotes and red foxes are canids that differ in body size and occur sympatrically in Wilderness Park, which suggests that they interact and could imply competition. In and around Lincoln, the number of coyote sightings has increased in recent years, Although the ecology of both species has been studied individually, more information is needed about how intraguild competition and interactions with coyotes (Canis latrans) affect the distribution and temporal activity of red foxes (Vulpes vulpes). To assess these interactions, I investigated the temporal and spatial activity patterns of coyotes and red foxes in Wilderness Park in Lincoln, Nebraska, using eight trail cameras deployed from 1 March to 11 April 2023. I detected co-occurrence of coyotes and red foxes at 3 of 8 camera locations. At 2 of the 3 sites where the species co-occurred, red foxes were detected at a rate greater than or equal to that of coyotes. However, the presence of coyotes appeared to have some impact on the detection rate of red foxes, as 4 of the 5 camera sites where coyotes were detected, red foxes were detected at a rate less than or equal to the rate of detections of coyotes. Throughout the park, both species were detected at nocturnal and crepuscular hours. Coyotes and red foxes had modest temporal overlap at the camera with the most detections of both species (∆1=0.51), and moderate temporal overlap across all camera sites combined in Wilderness Park (∆1=0.52). Avoidance-attraction ratios implied temporal avoidance of coyotes by red foxes at the camera with the most spatial overlap. The temporal distribution of red foxes was not uniform across the 24-hour cycle (RST .01 0.1). These results overall suggest that red foxes may be avoiding coyotes through both fine-scale temporal and spatial avoidance. However, low statistical power from a short study period and low number of detections limited the inferences possible with these data. Nonetheless, the study contributed to a better understanding of how red foxes and coyotes interact in Wilderness Park, and can help guide future research. Future researchers focused on spatiotemporal activity patterns of these species should obtain larger datasets across larger spatial extents where the species co-occur to build on these results and provide a greater understanding of the interactions between red foxes and coyotes.