Shrub encroachment is transforming arid and semiarid grasslands worldwide. Such transitions should influence predator–prey interactions because vegetation cover often affects risk perception by prey and contributes to their landscape of fear. We examined how the landscape of fear of two desert lagomorphs (black‐tailed jackrabbit, Lepus californicus; desert cottontail, Sylvilagus audubonii) changes across grassland‐to‐shrubland gradients at Jornada Basin Long Term Ecological Research site in the Chihuahuan Desert of southern New Mexico. We test whether shrub encroachment shapes risk differently for these two lagomorphs because of differences in body size and predator escape tactics. We also examine whether an ecosystem engineer of grasslands (banner‐tailed kangaroo rat, Dipodomys spectabilis) mediates risk perception through the creation of escape refuge and whether trade‐offs exist between shrub encroachment and the local reduction of banner‐tailed kangaroo rats caused by shrub expansion. We measured perceived predation risk with flight initiation distances (FIDs) and then used structural equation modeling to tease apart the hypothesized direct and indirect pathways for how shrub encroachment could affect perceived risk. A total negative effect of shrub cover on FID was supported for jackrabbits and cottontails, suggesting both species perceive shrubbier habitat as safer. Increases in fine‐scale concealment also reduced risk for cottontails, but not jackrabbits, likely because cottontails rely on crypsis to avoid predator detection whereas jackrabbits rely on speed and agility to outrun predators. Perceived risk was reduced when individuals were near kangaroo rat mounds only for cottontails because the smaller species can use banner‐tailed kangaroo rat mounds as refuge. Shrub encroachment greatly reduced the availability of mounds. Thus, a trade‐off exists for cottontails in which shrub encroachment directly reduced perceived risk, but indirectly increased perceived risk through the local extirpation of an ecosystem engineer. Our work illustrates how the expansion of shrub encroachment can create a dynamic landscape of fear for populations of prey species involving direct and indirect pathways contingent on prey body size, escape tactics, and activities of an ecosystem engineer.

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Red Foxes (Vulpes vulpes) often carry food items to caching sites and while making provisioning trips to litters. This behaviour provides opportunities to use camera traps to record Red Foxes carrying food that is likely prey. As part of a larger study using camera-trap surveys to monitor carnivore populations at Great Swamp National Wildlife Refuge, New Jersey, our cameras also recorded Red Foxes carrying food items allowing us to gain insight into the feeding ecology of this predator. Camera traps documented Red Foxes carrying food 71 times; items included mammals (78.9%), birds (19.7%), and fish (1.4%). Small mammals (unknown rodent or soricid species [23.9%] and voles [Microtus or Clethrionomys spp.; 5.6%]) were the most common groups of food items and Muskrat (Ondatra zibethicus; 15.5%) was the most common food item identified to species. Our surveys corroborate traditional diet assessments (e.g., scat analysis) of Red Foxes in North America, identifying them as a generalist forager that typically consumes smaller mammals. We also highlight the potential to apply camera trapping as a supplemental technique for gaining additional insight into the feeding ecology of this predator.

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