Bat yarns: A late night,Pips,BLEs,Noctules and Baby Bats....Manchester Airport Bat Barns

On the 16th June 2011, I awoke, already tired! I’d had rather an early start and a late end the day before. But, tired as I was, I was happy to be.

This was due to the fact that on the night of the 15th June 2011 I was invited via the Cheshire Bat Group to join their Bat Survey at the Bat Barns of Manchester Airport. I had researched a little into these barns at the airport and had also been advised by The Cheshire Bat Group that if the opportunity arouse it was one not to be missed.

The Bat Barns at Manchester Airport helped to replace a Brown Long Eared maternity roost that housed itself in a farm house; the farm house had been removed during the building of the new runway. The existing roof timbers of the farm house were used in the building of the new barns. Here, they mimic the same structure of the old house, but it is twenty five percent smaller. In total, three new Bat Barns and also the addition of two hundred and fifty bat boxes, in different designs to attract different species, have been erected in the area.

I’ll admit, as someone not good in a crowd, I had some trepidation as I arrived at the car park and saw quite a gathering of people. The assurance that I was in the right place came when I saw the usual wet weather and rambler attire that a group, planning on spending the late evening out in the elements were all wearing.
I (nervously) donned on my ‘wets’ ( trousers, jacket and hiking boots) and tooled myself up with my Bat Detector, a torch and my mobile phone and did my best to ‘loiter with intent’. We were waiting for Ged Ryan who had organised the evening and once he had arrived, we talked as a group and then he let us split up into groups depending on the Bat species we wanted to survey.

During my early days with my Bat Detector I have heard and identified Pipestrelles and Debaunton bats, so I opted to go and hear something different. I want to experience as many different species as I can so that I can train my ears to the varying characteristics of a species sound. Ged and a small group were heading for the Bat Barn known to have Whiskered Bats and others were off to seek out Brandts Bats in an adjacent barn. A third group took a drive down to where Pipesstrelles are more commonly seen.

I was lucky enough to be walking along side Dave (or 'Dr Dave' as he is affectionately known) who told me more about the Barns and the types of Bat Detectors he has used. Dave has a great interest in audio patterns and is certainly the technological mastermind of the group. He kindly explained to me, as we were walking through the woodlands, the Anabat devices that they have at the Barns and that tonight he wanted to check on their function.

Here comes the science bit.......

Anabat detectors are designed to help users identify and survey bats by detecting and analysing their echolocation calls. It is most widely used for passive detection, where the detector is us

ed as a logging device to monitor bat activity in the absence of human intervention. For active monitoring, bat calls can be recorded in real time using the Anabat system. Coupled with a PDA arrangement this gives the user maximum freedom of movement to follow bats on foot or from a moving vehicle

As we wandered over a wooden bridge towards the tunnels we split into two groups – our group headed for the Whiskered Bats.
I had never realised (as many from outside of the area have not) the construction of the runway and the affected surrounding area, but interestingly, walking under the runway along a natural water source and hearing about the Otter marks that had been seen here was an eye opener to the positive conservation steps within the area (this I know may be open to argument).
And don’t be mislead into thinking that you just get to stand about all night looking for Bats – we walked up some real steep inclines through brambles, woodland and uphill and dale on our way to the Barns that night.
When we arrived at the Barns (around 9.10pm), the heavens opened. Huddled under our coat hoods and umbrellas we prayed the rain might stop and worked hard to avoid any moisture getting into our bat detectors.

Half of our group stood beneath the highest exit of the barn, Ged and I wandered to the front side where there is an open grill and also some smaller wooden facia exits that the bats are known to use. Ged was kind to explain the lay of the local area and how the bats behave because of this. He mentioned that some of them do not ‘shout’ as they exit the barn because they know the route out; they do not anticipate any obstacles; it is when they are feeding that you might hear them the loudest here.

I had a lovely chat with Ged, who was forthcoming with his own history of working with bats and the many varied talks at schools he has performed over the years. As we chatted, he would check the thermometer that he had hung in a nearby tree and around 9.50pm we started to see the occasional bat pop out from the highest exit point. These were counted by the team covering that section.

We had a Pippestrelle exit from the facia board and then I started to pick up the movement of a bat that was flying up to the open grate and then back into the barn again. Ged believed that it was ‘light testing’ – checking the overall light levels before exiting. The bat flew up and back in four times before exiting, 5 feet from the ground swooping upwards right in front of us.

There was no sound from my bat detector!

As a novice, my first thought was that I was listening on the wrong KHz and therefore wouldn’t have picked any of its echolocation sounds up, but there was no sound to be heard on Ged’s detector either. From Ged’s experience he was immediately able to identify that this was a Brown Long Eared bat and that they are also known as ‘the whispering bat’ because they have such a ‘quiet’ call that our detectors do not allow us to hear them. The size of the bat was also an indication. It certainly seemed a lot bigger than the usual pip that I have been used to seeing. After about twenty minutes and with a flyby of a Noctule as it foraged high and around the open field to our right, another Brown Long Eared bat flew to the grate a handful of times and then exited. A short while later we saw another.

We had around 19 bats (Pips and BLEs) exit the barn that night and as the sun had set and a prolonged period had passed after the last bat exit, we were able to go into the barn to check the Anabat.
Red torches to hand we entered the barn – I had absolutely no idea what to expect so I followed the other more knowledgeable group members. We looked around the ground floor of the barn, peering up into the rafters to see if there were any bats hanging, but at first the only thing we discovered was a half sleeping blue tit.

Carefully climbing the ladder we went upstairs. A part built and evidently abandoned birds nest sat in the middle of the room and we could also see the bat droppings (Guano) that we had anticipated to find. Carefully peering into the rafters proved fruit full as a handful of tiny, silver baby bats (pups) were found. They looked healthy, a good size and were able to move around in the space freely and easily. This was a very exciting point of the night for me! It just seemed amazing that on my first survey, I had been able to see wild, live, baby bats and really healthy looking ones too. It was reassuring to find out that they were using the Barn as a maternity roost. I couldn’t believe my luck. I remember standing there taking in as much detail as I could in the quick glimpses that we got – I could almost feel the shutter in my photographic memory taking rapid snapshots, not wanting to forget a single image.

After a quick check on the barn and a good night whisper to the sleeping blue tit, we wandered back down the country trail to meet up with the group that had gone to check on the Brandts bats. They had had some success with their survey, but I was still immensely pleased that I’d had the chance to see baby bats!
The walk back was a little easier, despite having to continually avoid tiny newts, snails and frogs that be speckled the damp pavements. I also had quite a spring in my step after a night of Pips,BLEs, Noctules and pups. I got home and although I was tired I didn’t want to sleep. I had learnt quite a bit that evening and my mind was processing it all, conscious of not losing any of it.

For my first survey and first visit to the bat barns it was a wonderful experience and has instilled further that getting involved, in whatever way we can to help conserve these animals is worth every minute of the late night before!

Anna