Having cancelled all our surveys, we wondered what on earth we would do. One of our number has responded by putting his echometer touch out of his bedroom window, making recordings over night. He did this last week and got nothing, but last night he picked up 15 pipistrelle passes, and e mailed us with the news.
The bats are managing just fine!
Photo of pipistrelle in bfight by RHS
Usually we are inclined to say ” another pip” but that was then, this was now!
There are 3 types of pipistrelles in Bedfordshire. Without a bat detector you have little chance of identifying them. To be honest it’s not that easy with a bat detector.
You need to listen to the detector and work out where the call is loudest. (easier said than done, they often fly past before you can be sure ) Common pips peak at 45 soprano pips at 55 and Nathusius at less than 40 ( The latter is quite unusual in Beds)
That is the theory
In reality it depends on the environment and what other bats are about. A rule of thumb is if it’s between 40 and 50 call lit common, if it”s above it’s a soprano. This leaves 50-52 as “pip”.
Real anoraks use sonogram analysis and use bat detectors which record calls. Even then it can be hard to be sure.
Welcome to he strange world of bat calls.