Thursday, 26 June 2008

Welsh Bats and Scottish Bat-workers


Last weekend I made the long trek to Aberystwyth - a 7 hour drive each way - for the B.C.T. Welsh Bat Conference. Organised by Tom McOwat and hosted by Aberystwyth University, this was an excellent conference at a reasonable charge (even for us consultants, who usually pay extra). A pleasant surprise was the discovery that no less than nine of us were travelling down from Scotland, so with a bit of hectic organisation everyone squeezed into two cars and we did our small bit to save the planet and avoid having to remortgage the house to buy a tank of petrol.

There were a number of good talks. It would be remiss of me not to mention the two Scots: John Haddow describing tips for identifying bats in the hand and Kirsty Park on bats in man-made habitats.
Another highlight for me was Helen Miller describing BCT's new survey programme for the rare Bechstein's bat. This rare woodland bat is extremely hard to survey for: they fly fast and cover large distances, so the survey method employs an actic technique: using ultrasonic lures to attract Bechsteins into harp traps by broadcasting their social calls. Very clever, and with a strict methodology that minimises disruption to the bats.

Another fascinating talk was by Chris Corben, the innovative Australian who designed the Anabat system, which is revolutionising professional bat-work. The Anabat SD1 is a frequency division detector which saves data direct to a CF memory card. It allows effective long-term monitoring of bats and is increasingly finding a place in transect work too. With the associated Analook software, which is designed to work with frequency division data (unlike Batsound etc, which use audio files) it is astonishingly easy to analyse large numbers of bat passes swiftly and efficiently.

A very clever idea incorporated into the conference was the usual evening bat-walk. Except it wasn't the usual one. Instead, all the delegates were divided into teams and spread out over twelve woodland sites around Ceredigion. The result: a far greater survey effort in one night than most bat groups could manage in a year. And to validate the results, the Sunday morning session comprised analysis workshops for the various software programmes.

Naturally, the Scottish bat hooligan squad had to push things to the limit. Not satisified with six bat species in our patch of woodland (including a possible Nathusius' Pipistrelle - a very rare species), we wanted more. We set out to look for Lesser Horseshoes, which we were told had been recorded at a road widening scheme a few miles from Aberystwyth. Imagine the scene: a car bursting with wild bat enthusiasts and literally bristling with bat detectors, careering down a Welsh country road in the middle of the night. We had three Bat-box Duets poking out of the sun-roof (set to 20, 50 and 120 kHz), an Anabat SD1 poking out of the side window and one intrepid bat-worker (who shall remain nameless) hunched in the passenger seat, monitoring the frequency division output of one of the Duets, just in case a bat escaped all the other detectors.

So, did we get any Horseshoes? Did we heck. But at least we have an excuse to go back to Wales...if they'll have us!

My website: www.plecotus.co.uk

More on the Bechstein's Project: http://www.bats.org.uk/pages/bechsteins_bat_project.html

Chris Corben and Anabat: www.hoarybat.com

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