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Attributed North American Bat Monitoring Program (NABat) Master Sample and Grid-Based Sampling Frame

October 22, 2018

The NABat sampling frame is a grid-based finite-area frame spanning Canada, the United States, and Mexico consisting of N total number of 10- by 10-km (100-km2) grid cell sample units for the continental United States, Canada, and Alaska and 5- by 5-km (25km2) for Hawaii and Puerto Rico. This grain size is biologically appropriate given the scale of movement of most bat species, which routinely travel many kilometers each night between roosts and foraging areas and along foraging routes. A Generalized Random-Tessellation Stratified (GRTS) Survey Design draw was added to the sample units from the raw sampling grids ( This dataset represents the final 2018 NABat Sampling grid with various landscape level attributes added (country, state/territory, county, percent water, and land ownership/management). Grid cells that fall outside the area of interest were removed from each individual sampling frame.