Human activity and land use change impact every landscape on Earth, driving declines in many animal species while benefiting others. Species ecological and life history traits may predict success in human‐dominated landscapes such that only species with “winning” combinations of traits will persist in disturbed environments. However, this link between species traits and successful coexistence with humans remains obscured by the complexity of anthropogenic disturbances and variability among study systems. We compiled detection data for 24 mammal species from 61 populations across North America to quantify the effects of (1) the direct presence of people and (2) the human footprint (landscape modification) on mammal occurrence and activity levels. Thirty‐three percent of mammal species exhibited a net negative response (i.e., reduced occurrence or activity) to increasing human presence and/or footprint across populations, whereas 58% of species were positively associated with increasing disturbance. However, apparent benefits of human presence and footprint tended to decrease or disappear at higher disturbance levels, indicative of thresholds in mammal species’ capacity to tolerate disturbance or exploit human‐dominated landscapes. Species ecological and life history traits were strong predictors of their responses to human footprint, with increasing footprint favoring smaller, less carnivorous, faster‐reproducing species. The positive and negative effects of human presence were distributed more randomly with respect to species trait values, with apparent winners and losers across a range of body sizes and dietary guilds. Differential responses by some species to human presence and human footprint highlight the importance of considering these two forms of human disturbance separately when estimating anthropogenic impacts on wildlife. Our approach provides insights into the complex mechanisms through which human activities shape mammal communities globally, revealing the drivers of the loss of larger predators in human‐modified landscapes.

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Given their distribution, harbor seals (Phoca vitulina) are likely to interact with human activities and potentially be disturbed. However, it is unclear how human development affects the haul-out behavior of harbor seals near urban areas. Because disturbance related to human development may increase noise levels in air, one might expect seals to haul-out at times when airborne noise levels are low. This study examined the number of harbor seals hauled-out relative to time of day, noise levels in air, and tide level at two haul-out sites in the city of Bellingham, Washington, USA. Harbor seals were observed from May 2008 to April 2009. Two surveys were conducted every 1 to 2 wks-one during the day and one at night. Harbor seal counts and in-air noise levels were recorded approximately 100 m from each haulout site with binoculars and a sound level meter, respectively. Given the strong correlation between time of day and noise levels, one set of linear mixed effects models examined the interactive influence of time of day and tide level on harbor seal numbers. Another set of models examined the effect of noise level and tide level on harbor seal numbers. Despite fluctuations in harbor seal numbers in relation to time of year and haul-out site, more harbor seals hauled-out during the night than during the day. The best model for the number of harbor seals hauled-out included an interaction between time of day and tide level, and an interaction between noise level and tide level. This study indicated that numbers of harbor seals hauling-out in Bellingham were correlated with time of day and in-air noise levels. However, it is unclear if the nocturnal haul-out behavior of harbor seals was a consequence of human development. It is still possible that an unknown factor associated with time of day was responsible for the observed results. To tease out the correlation between time of day and in-air noise levels, a future comparative study between nearby haul-out sites-one close to human activities and one away from them-is recommended.