Sunday, 29 June 2008
The video was recorded between about 04.10 and 05.00 on a morning when dawn was around 04.30. A colony count the evening before showed that 383 bats left the roost. I hand-netted two of them and both were lactating females, indicating that this is a maternity colony. When I filmed them it was too early in the maternity season for the young to be flying, but in just a few weeks there will probably be double this number of bats, as each young bat starts to follow it's mother out to feed at night.
The video shows up to fifty bats at a time swarming and there are close-ups of one of the roost entrances, showing how the bats "touch and go" at the entrance, without actually entering. At times, so many bats were attempting to do so that there was an aerial queue and the clattering on the wooden barge-board as they touched and pushed off again was audible some distance away.
My web-site www.plecotus.co.uk
Thursday, 26 June 2008
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
Tuesday, 24 June 2008
Why then, are some local authorities still granting planning permission for developments without giving the slightest consideration to protected species? Edinburgh are the worst offenders I know of, but I'm sure there are others. I have recently seen a development involving the direct destruction of a known roost. I was called in by the owner to give advice on how to proceed and was appalled to discover that planning permission had already been granted.
On the other hand, some local authorities are diligent: the planners at Scottish Borders Council not only make it clear to applicants what species need to be surveyed for, they provide succinct guidance, written by the county ecologist and clearly focused on the individual development.
This process is the safety net through which pointless destruction of bat roosts can be prevented: ensuring developers and others face their responsibilities towards protected species and helping them understand what they need to do and when. It's basic and essential conservation law.
My other frustration is the local authorities who approach their Habitats Directive responsibilities with a "one size fits all" approach. One west of Scotland local authority responds to planning applications by setting out what programme of surveys must be carried out, without knowledge of the characteristics of the site or it's bat potential. Yet the BCT Bat Survey Guidelines are clear: "It is worth noting that the type of survey to be undertaken and amount of effort expended can often only be fully determined after visiting the site at least once." I recently completed a pointless set of sunset surveys at a modern city centre building with very low bat potential, no nearby or connected habitat and no records of bat activity in the area. The local authority's ecologist insisted on his standard litany of "two to three emergence surveys", with no mention of an initial inspection survey. After I carried one out it was abundantly clear that no further survey was necessary, but was obliged to do so anyway. As a result, the developers have been delayed, have paid over the odds and are disillusioned with the whole process. In other words, conservation has been discredited by thoughtless actions.
For all I know, their next development could be a steading conversion surrounded by prime habitat: a building with high bat potential. After their bad experience at this site, they could be tempted to turn a blind eye to protected species. If the local authority is one of those which does the same, the result could easily be the destruction of an ecologically sensitive roost.
Rant over (climbs down from soapbox).
Tuesday, 10 June 2008
Here you can clearly see the Bat-bug (Cimex sp.) on the bat's wing
And the other site? Only thirty bats emerged, suggesting that the maternity roost is probably somewhere else entirely. What we now need is someone mad enough to prowl the streets of Edinburgh at dawn for a few days, looking for a swarm of bats, to tell us where the maternity roost is! It's not that we really need to know, but it would be nice to find the missing jigsaw piece.
(Above) The roost entrance identified in May - the bats swarmed in front of this gable end and entered via the gap visible below one of the roof tiles
(Below) Droppings stuck to the timber facing below it, 3 weeks later
When I returned with a team of helpers at sunset last week, there were many droppings stuck to the wall around the access hole the bats had been using on the previous visit, indicating it had seen some use. However, at sunset no bats emerged from there. Instead, 118 bats emerged from two holes in the gable end of the main attic, right where I originally found piles of droppings within the attic. So, not only were we able to confirm the location of the maternity roost, the May visit enabled the identification of an intermediate roost, which wasn't apparent from signs within the attic.
Bats are always enigmatic and rarely give up their secrets easily. It's nice when, once in a while, we can see tiny bit more of their lives than the usual tiny snap-shots...
My website: http://ww.plecotus.co.uk/