Bat News
Bat Survey at King's Stand Farm
30 May 2008
Ten members of the batgroup took park in this first visit to a Farm close to Rufford Park and the Centre Parcs Holiday Village. The farm is the home of a member of the bat group and they were keen to see which species are found on the farm.
We began by looking around some of the disused farm buildings to see if we could find any evidence of bat use. Unfortunately the condition of some of the roofs made them unsuitable for bat roosts but we did four droppings (probably from a brown long-eared bat) in one of the buildings.
After our look at the buildings we ventured onto the farmland where we were soon watching a noctule hunt over a meadow. It was still very light so we had an excellent opportunity to study its flight pattern. It made many steep stoops in pursuit of prey and we recorded lots of feeding buzzes. Listen to a heterodyne recording of the noctule there is a feeding buzz at the end of the recording (Detector: Tranquillity II set at 19 kHz)
We then moved closer to the edge of the woodland which forms the boundary of Centre Parcs. Here we recorded more noctules and several common pipistrelle.
As we retraced our steps back to the farm we noted soprano pipistrelle and had excellent views, against the still light night sky, of a Myotis bat as it hunted along the a hedgerow. It was most likely a whiskered bat and as it was flying with a common pipistrelle it gave us an excellent opportunity to compare both species flight pattern. The pipistrelle was making lots of sharp and unpredictable twists and turns whilst the whiskered bat flew in a more regular manner flying in a straight line along the hedge towards us and then making a quick turn and flying back in the direction it had just come from.
The image on the left (click on it for bigger image) is a spectrogram from a recording made of the Myotis (whiskered) bat together with a common pipistrelle. You can clearly see the different type of call used by both species. The Myotis is a quick sweep down the frequencies with no clear peak frequency whilst the pipistrelle's call is longer in duration and has a definite peak at about 45kHz. Listen to the call here (recorded using a Tranquility II time expansion detector with the call slowed down 10 times)
