Lack of information is hampering efforts to develop effective mitigation and recovery plans for the ʻōpeʻapeʻa. We are investigating three aspects of their ecology: 1) habitat use, 2) home range size, and 3) roost selection
We determined bats’ home range size with a radio-telemetry study. Two teams with mobile handheld antennae determined the positions of radio-tagged bats at night and allowed us to map their core use areas, which likely encompassed foraging activity. Further, we set up four automated receiver stations to help determine positions and activity patterns of radio-tagged bats. Home range size (first 6 months of data) ranged from 1,200 – 26,000 ha.
To describe current habitat use, we deployed nine bat detectors in different habitat types at randomly chosen points. Detectors recorded bat calls for three consecutive nights in each habitat and then were rotated five times every other month. We used a generalized linear model fit by maximum likelihood with a negative binomial distribution, with night and site as random factors, and habitat as the fixed effect of interest. We found habitat to be highly significant (P <0.0001). The shrub and gulch habitats had the highest number of call-minutes, but also the most variation.