Western Great Lakes Bird and Bat Observatory

Bat Survey - 2016

Director Bill Mueller and board member Robert Holzrichter participated in acoustic surveys as part of the Wisconsin Department of Natural Resources’ Wisconsin Bat Program last year. Using devices that detect bats’ ultrasonic echolocation calls, they and other surveyors recorded bat activity while driving transects in diverse regions of the state between June 1 and July 15, 2016. Together, the surveyors recorded a mean of 33.4 calls per detector-hour, the lowest average since surveys began in 2013. Big brown bat, silver-haired bat, eastern red bat, and hoary bat experienced increases in mean encounters frequency, but encounters of the cave species most heavily affected by white-nose syndrome (eastern pipistrelle, little brown bat, and northern long-eared bat) declined across all regions. The Observatory houses AnaBat detectors that volunteers can use to participate in monitoring program.

On a state-wide basis, according to the DNR's Wisconsin Bat News, "night-time research by Wisconsin conservation biologists is helping unlock the summer habitat secrets of several bat species threatened by white-nose syndrome, including the state's smallest bat, the eastern pipistrelle, or "pip" for short. Shown here, the pip weighs about as much as a nickel and has a wingspan of up to 10 inches, consumes small beetles, wasps and flies, and can live up to eight years. While its winter hibernation sites are relatively well known in Wisconsin, almost nothing was known about their summer habitats in the state until now. That information will help better guide recovery efforts in the likelihood that white-nose syndrome dramatically reduces their populations." .