Abundance and Movements of Mammals on the INL Site

Distribution, Abundance and Movements of Mammals on the Idaho National Laboratory Site


  • Review all previously published literature on small mammal research conducted on the INL Site and compile species-specific results into a searchable database
  • Conduct trapping surveys to determine presence and absence of both common and rare small mammals in the Development Zone
  • Use ultrasonic detection equipment to conduct “digital mist-netting” of bats in the Development Zone
  • Fit 20 elk with Global Positioning System collars to determine (1) the extent to which critical habitat (e.g., calving grounds) for that species occurs within the Development Zone; and (2) when, where, and to what extent elk move between the INL Site and surrounding agricultural lands.


All previously published data for small mammals on the INL Site were reviewed, and a database containing information on the publications and species trapped, observed, etc. was compiled. Trapping surveys were conducted for small mammals in the Development Zone between May and August of 2009 and 2010. The trapping resulted in the capture of 634 individuals of fi ve different species in 2009 and 1,226 individuals of ten species in 2010. For each animal captured, location, sex, and weight were recorded.

An ultrasonic bat call detector was deployed in a cave in the Conservation Management Plan Development Zone during autumn and early winter of 2010. Analysis of data collected by this equipment is forthcoming.

Twenty female elk were captured and fi t with GPS collars in March, 2010, and during the capture data on body condition, morphology, and blood parameters were collected. Collars remained on study animals through November, 2010, at which time they were remotely released from animals and recovered via radio-telemetry so that location data could be downloaded.