In 1994, USGS scientists recognized that despite increasing concern for many species of bats known or believed to be declining, the data necessary to determine population status and trends were fragmented among agencies and organizations. Thus began the USGS Bat Population Data Project, which has become a multi-phase, comprehensive effort to compile existing population information for bats in the United States and Territories.
The initial phase of this project was developed to
- synthesize the existing bat population data and publications for the United States and Territories into a single web accessible database,
- test the utility of this data for estimating trends in bat populations, and
- evaluate the applicability of this data to design future monitoring programs.
The Bat Population Database (BPD v.1), the project’s initial product, compiles various components of bat population data from 1855-2001, particularly counts of bats at colony locations, location attributes, and a complete bibliography of bat publications (published literature, theses and agency reports, and State agency files) for the U.S. and Territories.
Next, a scientific workshop was convened to evaluate the current status of bat populations, the methods used to estimate their trends, and developing scientific goals for future monitoring programs. Participants included experts in bat biology, wildlife population monitoring, and wildlife population estimation. In 2003, the USGS Fort Collins Science Center published the results of the workshop in a USGS Information and Technology Report titled “Monitoring trends in bat populations of the United States and territories: Problems and prospects” (O’Shea and Bogan, 2003). This report includes a summary and analysis of the BPD v.1 data and its utility in guiding the design of future monitoring programs.
In the years since completion of BPD v.1 and workshop report, North American bat populations have continued to decline. Of particular concern have been the precipitous declines of hibernating bats affected by White-nose Syndrome (WNS), a novel fungal pathogen, as well as the significant threat to migrating bats from increasing wind energy development. These combined threats have generated renewed interest for data suitable for bat population estimation and trend analysis.
Currently, USGS scientists are responding to this need by upgrading, updating and extending the capabilities of BPD v.1 for better data management, accessibility and utility by USGS and data partners.

The objectives of this phase are to:
- Update existing bat population data and publications since 2001.
- Provide web-based BPD access to researchers and organizations.
- Provide advanced search capabilities including enhanced form-based searches.
- Provide BPD data partners with report and export services.
- Define standards for data collection and management to facilitate a standards-based approach for researchers.
- Facilitate collaboration and data sharing between BPD data partners.
Development of the next version of the database, BPD v.2, began in April, 2012 with the first of two planned Beta releases occurring in August, 2012. The initial Beta release provides selected users the ability to search for bibliographic references to bat populations by location, date, and species. In addition, search reports can display species distribution maps and summary statistics of current BPD data holdings. The second Beta release, expected in October 2012, will provide additional metadata and data management capabilities. BPD v.2 will become fully operational and replace the existing BPD v. 1 in December 2012.
Below are publications associated with this project.
A plan for the North American Bat Monitoring Program (NABat)
Estimating sample size for landscape-scale mark-recapture studies of North American migratory tree bats
Monitoring trends in bat populations of the United States and territories: Problems and prospects
In 1994, USGS scientists recognized that despite increasing concern for many species of bats known or believed to be declining, the data necessary to determine population status and trends were fragmented among agencies and organizations. Thus began the USGS Bat Population Data Project, which has become a multi-phase, comprehensive effort to compile existing population information for bats in the United States and Territories.
The initial phase of this project was developed to
- synthesize the existing bat population data and publications for the United States and Territories into a single web accessible database,
- test the utility of this data for estimating trends in bat populations, and
- evaluate the applicability of this data to design future monitoring programs.
The Bat Population Database (BPD v.1), the project’s initial product, compiles various components of bat population data from 1855-2001, particularly counts of bats at colony locations, location attributes, and a complete bibliography of bat publications (published literature, theses and agency reports, and State agency files) for the U.S. and Territories.
Next, a scientific workshop was convened to evaluate the current status of bat populations, the methods used to estimate their trends, and developing scientific goals for future monitoring programs. Participants included experts in bat biology, wildlife population monitoring, and wildlife population estimation. In 2003, the USGS Fort Collins Science Center published the results of the workshop in a USGS Information and Technology Report titled “Monitoring trends in bat populations of the United States and territories: Problems and prospects” (O’Shea and Bogan, 2003). This report includes a summary and analysis of the BPD v.1 data and its utility in guiding the design of future monitoring programs.
In the years since completion of BPD v.1 and workshop report, North American bat populations have continued to decline. Of particular concern have been the precipitous declines of hibernating bats affected by White-nose Syndrome (WNS), a novel fungal pathogen, as well as the significant threat to migrating bats from increasing wind energy development. These combined threats have generated renewed interest for data suitable for bat population estimation and trend analysis.
Currently, USGS scientists are responding to this need by upgrading, updating and extending the capabilities of BPD v.1 for better data management, accessibility and utility by USGS and data partners.

The objectives of this phase are to:
- Update existing bat population data and publications since 2001.
- Provide web-based BPD access to researchers and organizations.
- Provide advanced search capabilities including enhanced form-based searches.
- Provide BPD data partners with report and export services.
- Define standards for data collection and management to facilitate a standards-based approach for researchers.
- Facilitate collaboration and data sharing between BPD data partners.
Development of the next version of the database, BPD v.2, began in April, 2012 with the first of two planned Beta releases occurring in August, 2012. The initial Beta release provides selected users the ability to search for bibliographic references to bat populations by location, date, and species. In addition, search reports can display species distribution maps and summary statistics of current BPD data holdings. The second Beta release, expected in October 2012, will provide additional metadata and data management capabilities. BPD v.2 will become fully operational and replace the existing BPD v. 1 in December 2012.
Below are publications associated with this project.