Bat use of golf courses depends on surrounding landscape context

Abstract

Understanding how wildlife responds to altered ecosystems is an important conservation objective. Urban green spaces may support wildlife communities, but their internal and external environments vary substantially. Golf course design and management generally follow standardized best practices, and thus frequently contain similar ecological features. However, studies investigating their conservation value have produced discordant conclusions; therefore, we hypothesize that external environmental factors significantly affect their utility for wildlife. We used acoustic detectors to survey bats at eleven golf courses across a gradient of landscapes (urban, agricultural, and forested) over two years. We used generalized linear mixed models to examine how landscape features surrounding golf courses relate to bat activity. For most species, bat activity was greater on golf courses when the surrounding landscape contained fewer open spaces and more developed land. We conclude that golf courses situated in developed landscapes may provide important foraging habitat for bats. Notably, several species of conservation concern were more active on courses with larger patches of nearby forest. Given that management resources are finite, we recommend using the surrounding landscape to assess the conservation potential of golf courses and allocating effort to improve habitat on golf courses that are most likely to benefit bats and other wildlife.

Non-Native Plants Influence Forest Vegetative Structure and the Activity of Eastern Temperate Insectivorous Bats

“…At the center of each survey plot, we placed a Pettersson D500X (Pettersson Elektronik AB, Uppsala, Sweden) acoustic detector equipped with a full-spectrum omnidirectional ultrasonic microphone. We mounted the microphone approximately 3 m off the ground and angled it approximately 45 • upward into the airspace [41]. At each survey plot, we recorded bat echolocation pulses for two consecutive nights that were forecasted to have little to no precipitation and wind speeds below 10 km/h [41].…”

“…We mounted the microphone approximately 3 m off the ground and angled it approximately 45 • upward into the airspace [41]. At each survey plot, we recorded bat echolocation pulses for two consecutive nights that were forecasted to have little to no precipitation and wind speeds below 10 km/h [41]. The detectors were active from 30 min before sunset to 30 min after sunrise with a 500 kHz sampling frequency and medium trigger sensitivity to reduce nontarget noise recordings.…”

“…To minimize false-positive detections, we manually vetted every pass and corrected erroneous automatic classifications made by SonoBat. Because of their often indistinguishable pulse characteristics, we combined the little brown bat (Myotis LUcifugus) and Indiana bat (Myotis SOdalis, Miller & Allen) classifications into a single LUSO category, which we subsequently treated as a single sonotype [41,55]. A terminal buzz can be heard as a distinct pitch change when played at 10× reduced speed and visualized as a short burst of accelerating pulses in the sonogram viewing window [41].…”

“…Because of their often indistinguishable pulse characteristics, we combined the little brown bat (Myotis LUcifugus) and Indiana bat (Myotis SOdalis, Miller & Allen) classifications into a single LUSO category, which we subsequently treated as a single sonotype [41,55]. A terminal buzz can be heard as a distinct pitch change when played at 10× reduced speed and visualized as a short burst of accelerating pulses in the sonogram viewing window [41]. Although terminal buzzes can be identified using the sonograms produced by SonoBat, they often cannot be reliably classified into species because they are accompanied by changes in typical pulse characteristics.…”

“…Moreover, when a bat detects a prey item, it deviates from its consistent echolocation pattern and produces a terminal buzz, whereby the bat directs pulses toward the target prey at an increasingly rapid rate until it is found and consumed [40]. Therefore, the number of terminal buzzes recorded can be a proxy for foraging activity [41]. Acoustic monitoring studies have implicated low prey abundance caused by non-native plants in reduced bat activity [42].…”