Thursday, 1 August 2013

Barbastelle at Surlingham?

After setting up the recorder for the Norfolk Bat Survey, I took myself off for a walk in the dark round Church Marsh. I feel like I know this place like the back of my hand, but I like how it can shock and surprise me in the dark. Nightwalking is underrated.

From the hide, I awaited the impending Geese roost. Some great counts:
Greylag 193
Canada 27
Egyptian 13

There were also 4 Green Sandpiper probing the margins, my highest count this Autumn. By now, I was expecting the Bats to join me but I was disappointed. Single passes of Noctule, Common and Soprano Pip were all I managed until I approached the Church. (I should however comment on my encounter with a young Fox, one of the cubs from earlier in the year no doubt. I watched him for ages in the fading light, something I never would have gotten away with during the day.

The track leading to the church and the car-park has often been good for Bats, and tonight was no exception. Noctule passed overhead, and both Common Pipistrelle Species hunted right above my head. In amongst the noise from the detector, I picked up a Myotis sounding frequency, peaking at 32 KHZ. Possibly a Daubenton's (no water here, though) or maybe a Natterer's. Upon tuning the detector up to 45, the sound became faint, lost at 55. Back at 32, the detector was now emitting a series of smacks I did not recognise. Surely not?! I couldn't see any Bats,it was too dark by now (22.10). I have never knowingly heard Barbastelle, so despite picking the same frequency up again in the Churchyard I was prepared to accept it was a Natterer's, which would be a good record for me at Surlingham.
However, back home I have since listened to some recordings of Barbastelle and this sounds precisely like what I heard last night. The fact the strongest frequency was at 32 further adds weight to this claim. They can apparently sound 'Myotis like' in clutter, but the fast paced smacks are characteristic.
The buzz of detecting a Bat and hearing the clicks, smacks and bubbles never fades, but this was my first moment of genuine excitement whilst out detecting. I have emailed the Norfolk Barbastelle Study Group, hopefully for confirmation (difficult with single observer/listener and no recordings made) and I hope to try again in the early part of next week. I need to be out 20 minutes earlier. I can't tick it 'til I've seen it!

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