Two volunteers pause in their nighttime walk along a riverbank in rural Ireland. Suddenly their bat detector comes to life, clicking with the echolocation calls of a Daubenton’s myotis on the hunt for aquatic insects. As the clicks accelerate into a “feeding buzz,” they scan the river with the beam of a flashlight until the bat is spotlighted as it dips to the water and snags an insect with its feet. They record the event in their log, then resume their walk.
|Daubenton’s myotis. ©Rollin Verlinde
Similar scenes have been occurring each August alongside waterways throughout much of Ireland since 2006, when Bat Conservation Ireland launched its popular Daubenton’s myotis monitoring program. Nearly 400 volunteers participate, surveying more than 200 sites for these impressive bats that fly low over the water and gaff insects with their large feet.
Niamh Roche, a coordinator of the NGO’s bat-monitoring programs, says trained volunteers are an essential part of bat conservation and research in Ireland. The nation is home to nine bat species but relatively few bat scientists. Accurate information about Irish bats and their benefits has been rare and misconceptions are common.
In addition to its nationwide bat surveys to monitor bat populations, Bat Conservation Ireland, founded in 2003, also provides a central repository for bat data and serves as an umbrella organization for local bat groups.
“Under domestic and European Union legislation, all Irish bat species are protected and we are obliged to monitor them,” Roche said. Bat Conservation Trust of the United Kingdom developed the first Irish bat-monitoring plan in 2003 as an innovative car-based monitoring system.
Volunteers drive mapped routes at a set speed at night and record bat passes using time-expansion bat detectors. This system makes it possible to sample bat activity from large areas and varied landscapes in a single evening. Bat Conservation Ireland has managed the program since 2004.
Each team of two or three people in a single vehicle, with a flashing beacon mounted on top, follows a specified route for each survey. One person drives while the others navigate and handle the equipment. They clamp the detector to the passenger-door windows and record the output onto a minidisc. Surveys are conducted once in July and again in August.
“We analyze the data, identifying and counting the bat passes in the recorded sound files,” Roche says. Up to 70 volunteers participate in the surveys each year, completing two surveys each in a total of 28 locations. “With nine years of analyses, we are able to derive robust trends for three of our most common species,” she said. Common and soprano pipistrelles appear stable or slightly increasing, while populations of Leisler’s bats are increasing.
The Daubenton’s myotis waterways project began in 2006. After training, teams of two volunteers each walk 0.6 mile (1 kilometer) along a river or canal bank. They count the number of bat passes for four minutes at each of 10 locations. Each bat pass recorded on the bat detector must be visually confirmed with the flashlight.
Both the waterways and the car-based surveys are now cross-border projects that include both the Republic of Ireland and Northern Ireland. “Bats, of course, pay no heed to the borders drawn by humans, so our all-island approach is ideal,” Roche said.
By combining volunteer-based monitoring programs with extensive public education and outreach, Bat Conservation Ireland is producing and disseminating a wealth of new knowledge and understanding about bats. And, Roche said, “We’re seeing real changes in public attitudes about Irish bats and the benefits they provide to our island.”
BCI Members can read the full report on Bat Conservation Ireland in the Spring 2012 issue of BATS magazine.