Hawaiian hoary bat roosting bat detection trials, Hawaii Island 2019

Hawaiian hoary bats (Lasiurus cinereus semotus) were captured at multiple locations on the east side of Hawaii Island from May 2018 through September 2019. Radio transmitters were affixed to captured bats and, when possible, radio telemetry was used to locate bats in trees used for day-roosts. Detection trials for roosting bats were conducted from June to October 2019. Bats confirmed as present at roosts were used as “targets” to evaluate the efficacy of detecting bats with thermal imaging, and when not effective (i.e., during hotter parts of the day when the technique could not discern bats from warm vegetation), visual searching with binoculars was also investigated. Most bat detection trials (48 of 95; 51%) were limited to searches [...]