Emergence counts need no licence, and that is most of the useful data
What you would do
Stand outside a known roost from about twenty minutes before sunset and count bats emerging. Ninety minutes, four times a summer.
What needs a licence
Entering a roost, handling bats, or using certain surveys. None of that is required for emergence counts and none of it is asked of volunteers.
The skill
Counting. Detectors are lent for anybody who wants to try species identification and nobody is expected to.
