Bat boxes

Joined the bat group for some bat box checking at Legoland this morning.  As Legoland have an aquarium as part of one of the rides they have to have a zoo licence.  This also means that they have to spend some money on conservation projects.  They have been supporting marine charities but wanted something closer to home.  They funded 20 bat boxes last year and they are now being monitored.  It was my first time offering practical help.  I climbed ladders to retrieve boxes,  held ladders for others and even got to hold a bat (under strict supervision by a licence holder). We found 3 pipistrelles in two boxes.  The remainder were inhabited by spiders but had also been used by birds earlier in the year.  I've no idea how they managed to squeeze through the small slots. One box had an abandoned wasps nest complete with a desiccated hornet. 
We had been booked in by security and had passes with our names on.  At one point a stressed looking security guard arrived as he'd been told that a group of masked people were in the woods. He was very relieved to find it was 'the bat guys' and stood down the various groups of guards who were converging on us in golf carts.  We have to wear medical masks and gloves to protect the bats and us. 
Very enjoyable morning and I'm hoping to join them again in October.  
The picture shows a torch being shone through the bat's wing to help identify which kind of pipistrelle it was and whether it was an adult or juvenile.  This was a female,  juvenile, common pipistrelle.