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With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14‐week period (17 August–24 November of 2019). We sampled wildlife at 1,509 camera trap sites from 110 camera trap arrays covering 12 different ecoregions across four development zones. This effort resulted in 166,036 unique detections of 83 species of mammals and 17 species of birds. All images were processed through the Smithsonian’s eMammal camera trap data repository and included an expert review phase to ensure taxonomic accuracy of data, resulting in each picture being reviewed at least twice. The results represent a timely and standardized camera trap survey of the United States. All of the 2019 survey data are made available herein. We are currently repeating surveys in fall 2020, opening up the opportunity to other institutions and cooperators to expand coverage of all the urban–wild gradients and ecophysiographic regions of the country. Future data will be available as the database is updated at eMammal.si.edu/snapshot‐usa, as will future data paper submissions. These data will be useful for local and macroecological research including the examination of community assembly, effects of environmental and anthropogenic landscape variables, effects of fragmentation and extinction debt dynamics, as well as species‐specific population dynamics and conservation action plans. There are no copyright restrictions; please cite this paper when using the data for publication.

Mounting evidence suggests declines in the abundance and diversity of wild bees. Increasing habitat that provides forage and nesting sites could boost struggling populations, particularly in urban, suburban and agricultural landscapes. The millions of acres beneath aerial electric transmission lines, sometimes referred to as easements or rights-ofway, must be kept free of tall-growing vegetation and hence have the potential to provide suitable habitat for many native species. Prior work has demonstrated that bee communities in easements managed using alternatives to episodic mowing were more diverse than in nearby open areas, however true control sites within the easements were unavailable. In order to compare vegetation management protocols, we conducted a two-year study which enabled us to directly compare transmission line easements in three locations currently undergoing Integrated Vegetation Management-a dynamic form of management involving spot removal and herbicide treatment of unwanted species (treatment) with nearby sites undergoing standard management protocols of yearly or biyearly mowing (control). Results show that treatment sites had significantly higher abundance and species richness than controls. Seasonal differences were pronounced, with the spring fauna most affected Communicated by David Hawksworth. 1 3 Electronic supplementary materialby differences in vegetation management. In addition, the older treatment sites house more social bees, more parasitic species and a more even distribution of bees across nesting guilds. Finally, we established that treatment sites had distinct bee communities, further increasing their value as sources for native bee populations in the landscape. Overall, the data clearly show the value of implementing alternative active vegetation management in the land under powerlines to achieve an increase in the abundance and diversity of wild bees.

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.