Mapping and Analyzing Sighting Surveys on Andersen Air Force Base

Project lead: Claudine Tobalske

The Mariana fruit bat (Pteropus mariannus mariannus, common name “fanihi”) is a Federally-listed, threatened subspecies in Guam and the Commonwealth of the Northern Mariana Islands.  Fruit bat monitoring involving yearly field surveys is required by the United States Fish and Wildlife Draft Revised Recovery Plan for the Mariana Fruit Bat. The Spatial Analysis Lab has been mapping yearly survey results (observer locations, bat locations, line of sight and direction seen flying) since 2014. In collaboration with the UM Math Department, spatial analyses are used to generate population estimates of remaining fanihis.

Mildenstein, T.L.; Patterson, D.A., Tobalske, C., Alexander, I.R., Miller, R. 2014. Mariana fruit bat monitoring on Andersen Air Force Base. Final Report for Cooperative Agreement Number:  N40192-13-2-8007, prepared for NAVFAC Marianas.

U.S. Navy, 2017. Monitoring Mariana fruit bats on Andersen Air Force Base. Prepared for NAVFAC Marianas, Guam by Tammy Mildenstein, University of Guam, under Cooperative Agreement Number N40192-15-2-8001.

The threatened Mariana fruit bat.

Example of map generated from survey coordinates and observer's notes.