3 research outputs found
SNAPSHOT USA 2020: A second coordinated national camera trap survey of the United States during the COVID-19 pandemic
Managing wildlife populations in the face of global change requires regular data on the abundance and distribution of wild animals, but acquiring these over appropriate spatial scales in a sustainable way has proven challenging. Here we present the data from Snapshot USA 2020, a second annual national mammal survey of the USA. This project involved 152 scientists setting camera traps in a standardized protocol at 1485 locations across 103 arrays in 43 states for a total of 52,710 trap-nights of survey effort. Most (58) of these arrays were also sampled during the same months (September and October) in 2019, providing a direct comparison of animal populations in 2 years that includes data from both during and before the COVID-19 pandemic. All data were managed by the eMammal system, with all species identifications checked by at least two reviewers. In total, we recorded 117,415 detections of 78 species of wild mammals, 9236 detections of at least 43 species of birds, 15,851 detections of six domestic animals and 23,825 detections of humans or their vehicles. Spatial differences across arrays explained more variation in the relative abundance than temporal variation across years for all 38 species modeled, although there are examples of significant site-level differences among years for many species. Temporal results show how species allocate their time and can be used to study species interactions, including between humans and wildlife. These data provide a snapshot of the mammal community of the USA for 2020 and will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, and the impacts of species interactions on daily activity patterns. There are no copyright restrictions, and please cite this paper when using these data, or a subset of these data, for publication
Disturbance type and species life history predict mammal responses to humans
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.Human activity and land use change are driving declines in many animal species while benefiting others, but predicting which species will successfully coexist with humans remains a challenge. We compiled detection data for 24 mammal species from 61 populations across North America and showed that species life history traits were strong predictors of their responses to human footprint (landscape modification), with increasing footprint favoring smaller, less carnivorous, faster- reproducing species. Positive and negative effects of direct human presence (e.g., recreation, hunting) were distributed more randomly across species, with apparent winners and losers across a range of body sizes and dietary guilds.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/168486/1/gcb15650.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/168486/2/gcb15650_am.pd
Disturbance type and species life history predict mammal responses to humans
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.Human activity and land use change are driving declines in many animal species while benefiting others, but predicting which species will successfully coexist with humans remains a challenge. We compiled detection data for 24 mammal species from 61 populations across North America and showed that species life history traits were strong predictors of their responses to human footprint (landscape modification), with increasing footprint favoring smaller, less carnivorous, faster- reproducing species. Positive and negative effects of direct human presence (e.g., recreation, hunting) were distributed more randomly across species, with apparent winners and losers across a range of body sizes and dietary guilds.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/168486/1/gcb15650.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/168486/2/gcb15650_am.pd