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Human activities catalyse risk avoidance behaviours in wildlife across taxa and systems. However, the broader ecological significance of human‐induced risk perception remains unclear, with a limited understanding of how phenotypic responses scale up to affect population or community dynamics. We present a framework informed by predator–prey ecology to predict the occurrence of non‐consumptive effects (NCE) and trait‐mediated indirect effects (TMIE) of anthropogenic disturbances. We report evidence from a comprehensive review of the different types of human‐induced behavioural and physiological phenotypic changes and their influence on vital rates and population parameters in wildlife. Evidence for human‐induced NCEs and TMIEs is mixed, with half of published studies finding a relationship between human activities, phenotypic change and population outcomes. The net effects of anthropogenic NCEs and TMIEs depend on the mismatch between the phenotypic response and the lethality of human activity. However, strong research biases in taxa, systems, human disturbance types and demographic measures prevent unified inference about the prevalence of population responses to human activities. Coexistence with and conservation of wildlife requires additional research linking human‐induced phenotypic change to population and community outcomes. [ABSTRACT FROM AUTHOR]

Most extinctions worldwide have occurred on islands, primarily due to interactions with exotic species, but rarely due to interactions among endemic species. This potential exists on two of the California Channel Islands, Santa Cruz and Santa Rosa, as endemic island spotted skunks (Spilogale gracilis amphiala) appear to have rapidly declined to rarity, possibly due to interference competition with endemic island foxes (Urocyon littoralis). Niche partitioning is expected in response to interference competition; hence, it is surprising that skunks and foxes show extensive overlap in macrohabitat use and circadian activity. However, the role of microhabitat associations and fine-scale temporal activity in facilitating coexistence of the two species has not been explored. We evaluated microhabitat associations of island spotted skunks and island foxes across both islands using data from live traps and wildlife cameras collected during 2015–2017, and we analyzed fine-scale temporal activity using camera data from 2016 and 2017. On both islands, skunks had a positive response to ground-level cover provided by rugged topography or woody vegetation such as shrubs or trees, whereas foxes had a weak or negative response, suggesting partitioning of these microhabitat characteristics. Additionally, on both islands the peak in timing of skunk activity offset the peak for foxes, which implies that skunks use fine-scale adjustments in activity to avoid foxes. Past grazing by exotic herbivores likely reduced habitat refuges for skunks; however, as vegetation on both islands recovers, regrowth of shrubs and trees may provide cover that will improve prospects for coexistence of island spotted skunks and island foxes. [ABSTRACT FROM AUTHOR]