Give specific details on the location e.g. is it in the attic, under roof tiles, inside the building, in a tree hole, underneath bark of a tree:
Bat roost in an old oak tree in a former wood pasture now replanted with spruce and pine. located very close to Bunn sjön.
How long has it been used by Bats
Only This Year
How do you know it's a Bat Roost
How many Bats use this Roost approximately
Do you know what Species use the Roost
Yes, it is Eptesicus nilssonii roost. I recorded 454 passes of bats next to this tree and saw bats emerging.
How did you identify them
Using a Bat Detector
Do you have sound files of recorded Bats