As nocturnal hunters, bats use sound instead of sight to catch their prey, using echolocation to detect even the smallest insect in complete darkness. Echolocation relies on clicks produced by the bat that reverberate off solid objects, working like sonar to provide spatial information about its environment. The pitch, length and shape of these clicks or “pulses” change depending on the bat’s environment and choice of prey, and most importantly, they also vary among species. This key feature has allowed ecologists at 4 Elements to record bat calls in the field, and identify their callers based on unique, species-specific features.
Many bats echolocate at frequencies beyond the capacity of human hearing, which is where bioacoustic monitoring devices (BARs) become indispensable tools in the field, as they capture ultra-sonic calls that can be analysed and visualised with bioacoustic software. Recently, 4 Elements Consulting attended an intensive workshop in Brisbane focusing on bat call identification hosted by Titley Scientific. Survey techniques, equipment and call analysis were among the topics covered, as well as a comprehensive overview of the unique calls of many of the bat species found on Australia’s east-coast.
For EVNT listed species like the Bare-rumped Sheath-tail bat, large-scale developments can threaten roosting habitat and disrupt foraging behaviour. Understanding the presence and distribution of at-risk species is therefore crucial for informing future environmental management decisions and the impacts of development proposals. Using bioacoustic detectors, 4 Elements recently detected the presence of Bare-rump sheath-tail bats and other EVNT listed bat species in a previously unsurveyed habitat with the use of bioacoustic detectors.
Bioacoustic surveys and analysis form one of many diverse fauna surveying techniques used at Four Elements Consulting to capture the full picture of an area’s biodiversity. With these tools we can better understand those elusive, nocturnal species that often go unseen to better manage environmentally responsible and sustainable developments.