Question: Do you harm the bats

Keith Grehan answered on 16 Jun 2014:

As a rule no. The most common way to do this sort of field work is to take a blood sample and faecal swab (which is exactly what it sounds like 🙂 ).
After we catch a bat we take a tiny amount of blood from a vein on their wing, we then use a special powder that stops the bleeding (but mostly it has already stopped on its own within a few seconds) before taking our swab.
We keep meal worm nearby and feed all the bats before releasing them again. This is because we have interfered with the bats hunting for the night so we make sure they have had something to eat before letting them go.
While they are waiting to be processed (blood taken) the bats are kept in soft cloth bags where they can hang upside down and are kept warm and calm.
Most field work with bats in Europe is in conjunction with local bat societies who are interested in and concerned about the welfare of bats in their area. Both scientists and local teams work really hard to make our work as low impact as we possibly can.