Nathusius’ Pipistrelle

There is also a 3rd UK resident species of pipistrelle called Nathusius’ pipistrelle.

This bat appears to be widespread across the UK but in fewer numbers than either of the other pipistrelle species. It is slightly bigger and has a peak frequency of 38 - 40kHz.

Records of this bat are of interest to us. If you hear a Nathusius’ pipistrelle, with a peak frequency below 40kHz, please make a note on an additional sheet with the location and time but do not record on your form.

If you hear a pipistrelle with a peak frequency between 40 and 44kHz this is unsure as it could be either a Nathusius or a common (45) pipistrelle.

What to Record at Spots

When your two minutes at the spot is up, mark down the total number of pipistrelle passes and the total number of unsure passes.

Summary of pipistrelle peak frequencies:
38 – 40kHz = Nathusius’ pipistrelle – record presence on separate sheet
44 – 48kHz = common (45) pipistrelle – record passes on form
52 – 63kHz = soprano (55) pipistrelle – record passes on form

Peak frequencies out of these ranges, above 40 but below 44 and above 48 but below 52, should be recorded as ‘unsure’ passes on the form.

When you have completed the spot, get ready for the next walk by re-tuning your detector to 25kHz.