Nathusius' pipistrelle survey
Since 2009 we have been piloting a new survey at lakes/lochs, focusing on Nathusius' pipistrelle. A summary of results from the first four years of the survey is available here. We will be continuing the survey in September 2013 when we're particularly keen to get new sites surveyed in priority areas where there are large gaps in coverage. Sign up to take part.
Nathusius' pipistrelle is widespread across the UK but considered nationally rare, though it may simply be under-recorded. This species is migratory and the biggest influx of bats appears to be in September which is the peak month for in-the-hand and bat detector records. The UK also has a summer breeding population of Nathusius' pipistrelles, though only a handful of maternity roosts are known.
The key aim of this pilot survey is to improve our knowledge of the autumn distribution of Nathusius' pipistrelle across the UK. In future we would also like to gather sufficient data to look for evidence of changes in the levels of activity being recorded of this species across the UK if the findings from the pilot survey suggest this may be possible. The survey involves making recordings from broadband detectors so that Nathusius' pipistrelle records can be verified through sonogram analysis.
Site allocation
When you sign up we will allocate you a lake/loch that is at least 1km in perimeter and close to your address (ideally within 5km of you but not more than 10km).
Survey method
The survey involves two visits to each lake/loch, one between 1st - 15th September and the second between 16th - 30th September. In advance you will need to visit the lake/loch during the day in order to map out a 1km route around the edge of the lake/loch and mark out ten evenly spaced stopping points on your map. If surveying a repeat site we will send you the route map and spot descriptions from the previous year so that you can follow the same route as before. On the surveys bats are recorded while walking between stopping points and for four minutes at each stopping point. The surveys begin 20 minutes after sunset and should take roughly one hour to complete.
Equipment needed
Ideally you will need a frequency division bat detector (see our bat detectors page for more details) and a digital recorder or mini disc recorder plus an audio connecting lead and headphones. This will enable you to follow the standard survey protocol which will involve making continuous recordings as you walk your route. These recordings will be analysed in order to verify any suspected Nathusius' pipistrelle records. If you have access to sound analysis software and would like to analyse your own recordings then please let us know and we will supply you with the sound analysis protocol for this survey. If you have a time expansion or real-time full spectrum sampling bat detector you can also take part using the same survey methodology as for frequency division.
If you wish to use an Anabat bat detector then please let us know and we will send you an Anabat survey form and protocol for this survey.
If you only have access to a heterodyne (tuneable) bat detector then you can still take part, as the survey protocol also includes instructions for identifying Nathusius' pipistrelle in the field using this type of detector. However, it will not be possible to include these as verified records until the site can be visited with recording equipment in order to confim this species’ presence. Volunteers who report possible Nathusius' pipistrelle calls at their sites using the heterodyne method only will be prioritised for equipment loans the following year in order to try and verify this species' presence at the site.
We have a limited number of frequency division detectors and digital recorders we can loan out for this survey. You can indicate if you need to borrow equipment when signing up below.
Sign up to take part. Please complete the sign-up form even if you have taken part before so that you can provide the information we will need in order to send you the correct survey materials and equipment.
