Citizen Scientists Are Bat-tastic!

The Urban Ecology Center sponsors research projects that involve Citizen Scientists.  The term Citizen Scientist refers to members of the community who take part in gathering and analyzing data for any such projects.  This contributes to the UEC’s mission of creating a community that is knowledgeable of the local ecosystem and contributes to improvement of its overall health.

On the evening of May 2^nd, I attended an introductory bat monitoring workshop.  The UEC is the regional coordinator for the DNR’s bat monitoring activities in southeastern Wisconsin.  The monitoring coordinator gave an informational presentation on bats in Wisconsin, introduced the equipment used, and took the group on a sample bat monitoring walk.

Anabat Bat Detector

Bats search for prey by echolocation.  They make ultrasonic chirps, clicks and buzzes, then use sonar to narrow in on the location of their prey.  They will chirp at a steady rate until they locate prey.  As they hone in on an object, the chirps become shorter and faster until they catch their prey, and the call becomes what’s known as a “feeding buzz.”

Bat surveys are conducted using a device called the Anabat.  The Anabat is made up of a microphone, Bat Detector computing and global positioning system (the white box in the picture), and an attached personal digital assistant (the black box) that shows a visual representation of the bat calls.  The calls are recorded and stamped with the date, time and location of each call.  After a monitoring session is completed, the data is uploaded to the Wisconsin DNR.  The recorded calls are mapped and species identified based on call frequency.

All data sent to the DNR will be used to determine species richness and abundance of the the Wisconsin bat population.  Surveys are particularly critical in the spring and fall migratory seasons.

A typical bat walk should begin half an hour after sunset on a dry day.  There should not be wind gusts of greater than 30 mph (bats won’t be flying).  The walk should cover three kilometers, or last one to three hours. 

Our group set out at 8:30 pm for a practice walk around the athletic field of Riverside High School, taking turns monitoring the Anabat.  The air temperature was 71^o, relative humidity at 62%, and 4 mph wind speed.  As we located the direction of the bat calls, we were able to see the bats flying low over the field.

Our data was sent to the DNR, and we received the map below.  Each colored square represents a location where a call was recorded.  There were most likely two to three big brown bats (Eptesicus fuscus) feeding over the playing field that evening.