Sophisticated detectors capture “bat signals” in Alberta
On a clear evening in the summer of 2017, Nature Conservancy of Canada (NCC) volunteers and members of the public joined Cory Olson from the Alberta Community Bat Program (ACBP) on a trip to Gambling Lake, an NCC property just east of Edmonton, to watch and listen for bats. Their mission: to capture data vital to helping inform NCC species management decisions.
Gambling Lake is surrounded by trees, which the bats like to roost in. And the timing was right – July and August are the most active months for bats. On that one summer night, Olson and his cohorts detected 67 bat flybys and three species — one of them the SARA-listed endangered little brown bat. What technical sorcery allowed the researcher team to gather and interpret this data on the fly? We talked to Cory Olson about his work with bats in Alberta and the sophisticated devices he uses to collect information on them.
Gathering valuable data for scientific use
The Alberta Community Bat Program is an initiative of the Wildlife Conservation Society Canada, developed in collaboration with Alberta Environment and Parks and the Alberta Bat Action Team. The program began in 2015 with the aim of raising awareness of bat conservation issues, and to improve how bats are managed throughout Alberta.
An important objective of the ACBP is to facilitate the research and monitoring of Alberta’s bat populations — information that is critically needed before the arrival of white-nose syndrome (an introduced fungal pathogen that has already decimated bat populations in eastern North America and continues to threaten bat species).
Olson, a bat specialist and independent wildlife biologist, has been the program’s coordinator since its beginnings. The data gathered during the event will contribute to a national database of bat observations. Observations of bats, such as those observed during this event, can be submitted to the Neighbourhood Bat Watch program (batwatch.ca), which is run in partnership with the ACBP.
The ultrasonic detectors that Olson uses to capture the high-frequency sounds that bats make are almost as interesting as the bats themselves. “All bats in Alberta echolocate above a frequency we can hear,” Olson explains. However, bats echolocate continuously while flying and are easily detected with the right equipment. Despite being inaudible to humans, their echolocation calls are quite loud. During his bat walks, Olson uses the bat detectors to record these echolocation calls and later sifts through the data to determine what species were “heard.” Olson also uses a device, called the Wildlife Acoustics Echo Meter Touch, which plugs into a tablet or smartphone to translate the bats’ high-frequency calls into a lower-frequency sound that humans can hear — adding a further sense of wonderment and insight into his bat walks. The device also provides a visual display of the sound, called a spectrogram, and provides a list of potential species that could have produced the calls.
Helping Nature Conservancy of Canada make sound bat management decisions
Beyond Olson helping NCC identify particular bat species and calculate species inventory for specific NCC properties, Zoë Arnold, Conservation Volunteers coordinator for NCC’s Alberta Region, explains how Olson’s work helps NCC in its species management decision making and operations. “We work with Cory to understand if we need to put up bat roosts, or if there is already suitable habitat and we need to just let them be.” For example, Arnold says, on NCC properties with old buildings populated by bats, Olson will help NCC decide if it needs to provide a better habitat for the bats or if the existing structures are best. “He’ll (also) help us figure out if there are any management techniques we need to change,” she says. Olson is also working with NCC to establish a monitoring program near Gambling Lake to contribute long-term monitoring data to the North American Bat Monitoring Program.
Olson has more public bat walks planned for 2018. Watch the ABCP’s website and social media channels for more information.