Slindon – Advanced Bat Survey Techniques August 2018

batdan course

Diary of the annual Bat CRU Advanced Survey Training course on the South Downs August 2018

Target species this year are Alcathoe’s bat where we are aiming to locate a colony which we know is around from previous captures in the location, and Barbastelle bat in a location one was recently tracked to, which may prove to be a new colony.
The beginning of the course covers an introduction to the Bat CRU and its purpose, what we’re aiming to do this week, ethics of advanced survey, and practical sessions where attendees practice putting up harp traps and mist nets.


All bats caught under licence for various research projects, the course combines actual research projects with training.


A new site for BatCRU last night (31st July 2018), and more successful in the trapping stakes with a male Barbastelle first, then a flurry of Juvenile Alcathoe’s bats, and a brace of Bechstein’s bats. One of the Alcathoe’s bats and the juvenile Bechstein’s bat were tagged and the team is now out trying to locate the tree roosts (one of the course leaders has already found them, but this is a training course!). A key part of the course is learning radio tracking so this is a great opportunity.

Hopefully tonight and/or tomorrow morning we’ll be using infra-red camera’s to count the bats out and watch some amazing dawn swarming.

An impromptu radio tracking practical locating the Bechstein’s roost, and the Alcathoe’s bat roost, both in oak trees. This was followed by the workshop on radio tracking and marking bats, during the classroom session.

A quick meal then it was off to another new South Downs site… targeting Barbs….a good number were filmed leaving a roost in an oak tree at emergence, we caught 13 and a host of other species. DNA samples were taken and bats were ringed as part of a long running project.

Course attendees were treated to a spectacular misty sunrise on the way back from the Bechstein’s roost, before heading back to base camp for a few hours sleep.

The afternoon workshop centred on Infra-red cameras and the benefits they bring which we highlighted on the dawn at the Bechsteins roost.

Today’s menu includes the use of Acoustic lures, a Bechstein’s bat emergence, a Barbeque and swarming survey.

Final night of the course was a high point, following a great Barbeque and discussion about project ideas over the meal, we headed to watch either a Serotine roost emergence or the Bechstein’s bat roost emergence, unfortunately the latter had moved and there was no time to locate the new roost. After this we headed to a swarming site catching 55 bats of nine species. DNA samples were taken from the barbastelle and many of us took photos of bats in flight using Daniels IR light set up and the highlight of the night was the female Brandt’s bat, which are very rarely caught in the area.

We’re already considering next years’ course so watch this space for details!!