Skip to main content

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


Publication Date


Talbert, C., and Reichert, B., 2018, North American Bat Monitoring Program (NABat) Master Sample and Grid-Based Sampling Frame: U.S. Geological Survey data release,


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 sampling design produces an ordered list of units such that any ordered subset [...]

Child Items (6)


Point of Contact :
Brian E Reichert
Originator :
Colin Talbert, Brian E Reichert
Metadata Contact :
Colin Talbert
Publisher :
U.S. Geological Survey
SDC Data Owner :
Fort Collins Science Center
USGS Mission Area :
Distributor :
U.S. Geological Survey - ScienceBase

Attached Files

Click on title to download individual files attached to this item.


The GRTS design provides solutions to several practical challenges faced by bat surveyors that are not provided by more familiar designs such as simple random, stratified, and systematic sampling. The GRTS design allows for sample site additions and deletions, supports unequal-probability selection of survey locations, and provides an approximately unbiased neighborhood-weighted variance estimator that takes advantage of the spatial structure present in the surveyed population.

Additional Information


Type Scheme Key
DOI doi:10.5066/P9O75YDV

Item Actions

View Item as ...

Save Item as ...

View Item...