The first step is putting the bat under anesthesia. Flying foxes are VERY squirmy, and it is safer for everyone to have them sedated while we are taking samples. We use inhalant isoflurane administered through a mask, which will usually put a bat to sleep in just a minute or two. The hardest part is actually finding the bat's head while it is still in the pillowcase, and placing the mask on top. Sometimes you will wonder why a bat is taking longer to go down than usual, and then you'll realize that you've been trying to anesthetize its rear end. Once the bat's legs have gone limp, we take it out of the pillowcase and start collecting data.