14 Sep 2011 The detectability of bats: a question of biology or technology?
There are now numerous detectors available to help ecologists monitor bats, but what are their limitations and how good are the data that they produce? BSG has been working with Bristol University to try and come up with some answers.
Following on from this research, BSG has been invited to present the results of this research at the forthcoming Bat Conservation Trust National Bat Conference on September 17th 2011 at the University of Warwick. The presentation, which will be given by Matt Hobbs, will highlight the results from a collaborative research project undertaken by Matt with bio-acoustician Dr. Marc Holderied from Bristol University.
The research work looked at the issue of the comparability of data generated by different bat detectors. A total of six commercially available bat detectors were calibrated and compared using digitised playbacks of calls from eight species of UK bats. The next step was to calculate the area over which each bat detector model actually detected different species of bat, taking into account factors such as environmental conditions. The results were then used to derive correctional factors to allow for the differences in the detectability of different species of bat.
The results of this highly original study show that there is substantial variation in the overall detectability of different UK bat species and also variation in the sensitivity of different bat detectors to different bat calls. Following the lab work, Matt and Marc also supervised a Masters student at Bristol University during 2011, who field-tested the same bat detectors as an exercise in ground-truthing the lab results. The presentation will also summarise the results of this work.
Dr. Marc Holderied – University of Bristol, School of Biological Sciences