Originally distributed April 2009
We’re now doing a project on bats that roost in people’s houses. The project does not focus on the fact that they roost in these places, but we have to catch them there as they leave their roost at sunset.
The bats have to be tracked by vehicle because they cover a lot of ground quickly and often change direction. So we can only track one bat at a time because we only have one vehicle. Each bat is followed for 3 days, so every few days we trap bats and tag a new one. The roost that we chose is in a house that has a vent on one exterior wall that the bats enter and exit from every day. It’s about 10ft above the ground. As the bats take off in the evening they swoop down out of the vent and start flying as they’re falling toward the ground. They don’t fall on the ground, but they do have to drop to take off. They can’t leap off of something and start flying. We figured out that a simple trapping device, a 5 gallon bucket nailed to an 8ft wooden post, would do the trick. You simply hold the bucket under the vent and as they come out you catch them in the bucket before they can start flying. It’s brilliant!
There are 5 of us in the field—the two Danish grad students Kristine and Christina, their Irish field assistant Adam, Mduduzi, and me. We take turns catching the bats as they come out of the roost. One evening, Mduduzi was off and Adam was on bat catching duty. He was in position ready to catch them as they emerged. Kristine, Christina and I watched from a distance and told him when they started to come out so he’d know to move the bucket into position. As they were coming out we shouted, “Lift! Lift! Higher! Higher!” With a satisfactory catch we all started walking back to the vehicle, where all the tagging equipment is. Kristine was walking near Adam and I was walking ahead with Christina. Then Christina and I hear from Adam, “Kristine, what are you doing?!” Then we hear Kristine, “What’s wrong with you?” We turn around to see Adam. His jacket is on the ground. He lifts the back of his shirt and a bat flies out! We all died laughing.
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