6th June - 25th June (except lesser horseshoe: 29th May - 17th June, and greater horseshoe: 7th - 21st July)
How to take part
Surveyors are asked to count numbers of bats emerging from roosts at sunset on two evenings during the survey period. Surveyors choose their own roosts.
The species we focus on are:
pipistrelle, serotine (England/Wales only), and Natterer's,brown long-eared, and lesser horseshoe bats.
Greater horseshoe colonies are also counted. This survey is co-ordinated by the NBMP on behalf of Natural England and Countryside Council for Wales, and any data collected is sent on to them.
Please count lesser horseshoe, serotine, Natterer's and brown long-eared colonies in preference to pipistrelle colonies if you know of roosts of these species.
We focus on the above-mentioned species as they more often roost in buildings, making them easier to monitor. However, if you know of roosts of other species then please do get in touch at firstname.lastname@example.org, as we are interested in collecting data on other species, as well.
If you do not know of a colony in your area to count, you may be able to help your local bat group.
If you have access to a bat detector then we need your help with our bat detector surveys. The simpler of the two is the Waterway Survey which just requires you to count Daubenton's bats as they skim over the surface of the water. The Field Survey is for more experienced surveyors who are able to identify noctule, serotine, common pipistrelle and soprano pipistrelle in the field. If you have access to a frequency division detector (such as the Duet) and a digital recording device, you can take part in the Woodland Survey which focuses on the rare barbastelle. If you are interested in improving your skills we run bat detector workshops, so that volunteers can take part in our surveys. Or you might like to help find some new roosts in your area by taking part in the Sunset/Sunrise Survey, which is aimed at beginners.