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Monday, 30 January 2012

Memories of Summer Bats

This post has absolutely no meaning or purpose, except that I was tidying up my hard drive and realised I had recorded several video sequences of bats in the hand over the past year or so. It's minus four outside and the only bats I have seen for a couple of months have been deep in torpor (hibernation). So, to relieve the winter blues, here are some lively, wriggling bats to enjoy...

First, a Brown Long-eared Bat (Plecotus auritus). This was one of a group of 12 in a bat box on a golf course near Edinburgh. I filmed several sequences, trying to get the bat to extend it's massive ears, but the best I could get from it was the wiggle of its ears you see here. Long-eared Bats use their ears like parabolic dishes, concentrating sounds made by prey such as harvestmen, spiders and larger moths, allowing them to minimise the intensity of their echolocation calls. Some of their prey have rudimentary hearing and this prevents them from hearing the bat's approach.

Next up is a Noctule (Nyctalus noctula). This is the biggest bat species found in the northern U.K. This female demonstrates nicely the importance of using the right hold and the correct amount of pressure when holding a bat (see the note as the end). To begin with she struggles to free herself, but she quickly realises that she is secure and relaxes.

Next is a Soprano Pipistrelle (Pipistrellus pygmaeus). It's not a particularly good video segment, but it sits quite nicely beside the previous segment as the Soprano is our smallest bat and looks tiny by comparison with the bruiser in the previous video!

Lastly, here is a longer segment of a male Whiskered Bat (Myotis mystacinus). This species is quite rare in this region, so I took the opportunity to record a video showing some of its morphological features. Whiskereds are hard to tell apart from Brandts Bat (Myotis brandtii) or Alcathoe's Bat (Myotis alcathoe). One of the best characters for telling them apart is their dentition, though examining the teeth of a small and annoyed animal isn't always easy! Sadly the camera I had available on that day wasn't capable of showing that level of detail, so you can't see the teeth very clearly.

Important note - disturbing bats in the United Kingdom or anywhere in the European Union is an offence unless you hold an appropriate license. In the UK these are issued by one of the statutory nature conservation organisations (Scottish Natural Heritage, Natural England, Countryside Council for Wales, etc). If you would like to learn to work with bats your best starting point is to contact your local bat group for help, advice and training.

See the Bat Conservation Trust Website for details of your local bat group: Local Bat Groups

My website:

Saturday, 21 January 2012

Navigate that bat!

This is an exciting time for bat survey technology: after a number of years of stagnation the equioment available for surveying bats is taking some serious leaps forward. A number of new pieces of equipment have appeared on the market over the past 18 months and several more will be available soon. But sometimes it's not the equipment that matters so much as how you use it.

I have been using Anabats extensively for a number of years, both for passive monitoring (automatic recording of bats in flight) and for transect surveys(walking or driving a survey route, recording bat activity). The Anabat's ability to be connected to a GPS unit to record grid reference data alongside recorded bat passes is especially useful in understanding bat activity as you can plot the location of each bat pass accurately on a map. However, this tends to take a bit of post-survey work (unless you use a personal computer with your Anabat/GPS combination...but madness lies that way if you're not an uber-geek).

The flexibility and potential of Anabats for generating extensive high quality data has led them to move out of the realm of the professional bat ecologist and into the hands of voluntary bat groups around the UK. They're not cheap at around £1400 each, but many enterprising bat groups have obtained funding and are using their Anabats to great effect, generating lots of new biological records of bats.

A Bat-Nav in place on an Anabat SD1. In practice I found that the magnet wasn't sufficiently powerful to hold it in place (photo copyright Wildwood Ecology)

Recently I came across a new gadget, designed to be used in conjunction with an Anabat. In essence Wildwood Ecology's Bat-Nav acts as a GPS plugged into your Anabat and feeds it grid references as you walk or drive around. It comes with a simple but effective computer Widget, which uses Excel to extract your bat records and GPS file and generate a KML file. This file allows you to see your bat records plotted on Google Earth with a miniumum of fuss.

The Bat-Nav is designed to be used with an Anabat SD2 and draws its power supply from the USB socket on the machine. As I only had an older SD1 available for testing Wildwood kindly rigged up a wire to connect to the positive side of the battery pack, which worked ok. Since then Wildwood have launched a model designed to be used with an SD1.

To test the Bat-Nav in practice I used it to do a car-based survey around my home village one night in September. Wildwood suggest the unit can be attached by it's own magnet to the Anabat's own steel casing. I found the magnet too weak for that, but it stuck to the car door very well.

I recorded plenty of bats during a 2 hour drive. When I got home I used AnalookW to identify and label each bat call and created a count labels file in the usual way (if you've never used AnalookW, it is a delightfully easy to use piece of software for identifying bat calls which, with a few clicks allows you to create a simple spreadsheet). I then opened the data in the BatNav KML generator (see above) and after half a dozen clicks I had a KML file. All I had to do was click on the file for it to open in Google Earth (you probably have to have Google Earth already installed) and here is the result.

The transect route is shown as a yellow line, with each bat pass labelled (I chose to label P5 for Soprano Pipistrelle, P4 for Common Pipistrelle, Psp for unidentified Pipistrelle and Msp for Myotis). For anyone with access to GIS software (and the training to use it) this kind of thing is easily prepared, though it takes a little time. If you don't have acces to GIS or want a quick and simple way of looking at your bat data geospacially, this fits the bill. You can also manipulate the data three-dimensionally in Google earth and even look at it in Google Streetview, as you can see below.

Would I buy one? I think I would, though it's not without drawbacks. The area I chose for my test survey is in open farmland and the terrain is clear to see from the air. A woodland transect would be far less clear, with the tree canopy tending to hide paths and some roads and structures. Sadly Google Earth does not (so far as I know) allow you to convert between the satellite view and a decent map view (for that you need, which allows you to use Ordnance Survey maps as well as satellite images. Unfortunately it's part of Microsoft's evil empire, but these are the breaks).

Another niggle is that the magnet is disappointingly feeble, making it less usable for walked transects, but some sticky-backed velcro would probably sort that out.

Of course £150 is rather a lot of cash to shell out, especially if you already have a GPS receiver you could use. A friend of mine said it just took him a couple of hours, playing with Excel and Google Earth, to work out how to produce his own KML files. But he's a bit of a geek (sorry Tom). Perhaps Wildwood should consider selling the KML generator widget separately from the magnetic GPS - they may find some customers who are already happily using a normal GPS with their Anabat, but would like the hassle-free conversion to KML.

Wildwood Ecology -

My website -

Send me your thoughts/comments - email David Dodds

Saturday, 14 January 2012

A major threat to biological recording

If there is one thing which underpins all wildlife conservation work it is biological records. Data on what species live where allows us to understand wildlife better and to plan how best to conserve it. Without biological records we are simply groping in the dark.

A major weakness of professional ecology in the UK (and to some extent amateur natural history) are field skills: the ability to accurately identify species and habitats in the field and record their presence. Universities are churning out ecology graduates who in many cases have spent only a week or two in the field during 3 or 4 years of study. The result is a glut of graduates, but a shortage of graduates who are able to do fieldwork without extensive further training.

Many people turn to postgraduate study in order to address this and by far the best course has for a number of years been the University Certificate, Postgraduate Diploma and MSc courses in Biological Recording run by Dr Sarah Whilde's team from the University of Birmingham, based at the Gateway Centre in Shrewsbury.

Unlike most other courses, these are ideal for those who already work full time and offer enormous choice of species groups to work with. Individual modules are run intensively over 3-5 days at Field Studies Council centres around the country by expert specialists. I was fortunate to study the MSc course and gained enormous benefit as well as great deal of pleasure.

Now these successful courses are under threat. The University of Birmingham took the astonishing decision to close the centre. This is not for financial reasons, in fact they admit that the courses make a strong financial contribution to the university. They wish to close them simply because they do not fit with current research goals at the university. Quite apart from the barking mad concept of a publicly-funded body throwing away a good source of income, the closure of these courses would be enormously damaging to the quality of ecological surveying and biological recording in this country.

After massive pressure the university have conceded that they will attempt to move the courses to another university, but they have made no promises.

Please take a moment to sign the on-line petition against this move and help persuade the university that these courses are too important to conservation and to wildlife education for them to be threatened in this way.

Biological recording petition

Sunday, 8 January 2012

There's Nowt So Queer As Folk...

...whom you meet on bat surveys.

Back in May 2008 I wrote about some strange occurrences during bat surveys (What is it about bat surveys? May 2008). It sometimes seems inevitable that if you meet someone during a survey, there will be something less than normal about them or their activities. I thought it was time to update you with a few of the odd characters I have met and strange situations I have found myself in since then.

Sometimes you meet regular-seeming people, who turn out to have a secret. I was recently setting up a survey in a rural area when a farmer stopped to ask if we needed any help. You know you're in a properly rural area when strangers offer help without being asked - antisocial city dwellers please note. I explained to him that we were doing a vehicle survey for bats, showed him the equipment we use and we chatted for a while about bats and wildlife. Like most farmers he was highly aware of the wildlife around his farm. He described the bats he sees around his farmyard and invited me to drive through after the survey and take a look. Having a bit of time to spare later I drove through his farmyard and bats weren't all I saw. Perhaps he had intended to draw the curtains on the room that contained his cannabis-growing operation but was distracted by some livestock emergency...

Meeting the police during bat surveys is a fairly regular occurrence during surveys. If we are doing something liable to look suspicious I used to call the local station and let them know, to avoid wasting their time with an unnecessary visit. These days the local cop-shop is probably unmanned at night and I object to spending half an hour talking slowly to a disinterested call centre person who usually fails to advise the local patrol of our presence anyway. So explaining to bored coppers what we are doing is a regular thing.

Whilst carrying out a dawn survey close to an international airport I had a less run-of-the-mill encounter with some less run-of-the-mill police Officers. During the survey I heard shots fired in the near distance. "Bird scaring at the airport", I thought and carried on undaunted. A little while later, as I was leaving I saw a police car approaching at some speed. Apart from the everyday odd behaviour native to all bat workers I was probably looking especially suspicious. The site I was surveying was a building within a massive security fence. It was just a couple of hundred metres from the main runway of the airport, so just the sort of place your average terrorist might find alluring. And here I was, desperately trying to disguise the fact that I was placing the key to this high security compound under a brick beside the gate (my client's idea and not one I was in a hurry to take the credit for with the boys in blue).

The police car did a rather impressive screechy-wheel stop across the road, matched a moment later by another one. All very interesting...until machine-gun toting airport police leaped out, fanned round me and told me to keep my hands where they could see them. You never really know what you're going to do when placed in a dramatic situation, but my brain was whirling with three slightly worrying facts: these guys clearly mean business, in a moment they are going to ask me to explain my highly suspicious behaviour and my answer is going to involve furry flying animals...

It turned out that, whilst I may look suspicious, I don't look at all threatening (which was actually a bit disappointing). Apparently I had been right about the shots, but someone else had heard and reported them, giving Starsky and his mates an opportunity to go play. The really odd sequel was when, having finished with me, one of them asked me to wait as "the Chief Super wants a word with you". After a few minutes a much sleeker police car arrived and out climbed someone whose uniform had a lot more shiny bits on. This is where things took a surreal turn. It was 5am, I was utterly knackered, having been up since 1am and I had just been held at gunpoint. "They all think this is funny" he said, indicating the now grinning coppers "but I've just been appointed to take over the wildlife crime unit. Do you have time for a chat about wildlife crime priorities?" "Errr...ok". That was a very unusual morning.

On another occasion a police patrol stopped, to enquire if everything was ok, as our car, with an amber flashing beacon on the roof and reflective "surveying" sign on the back was stopped at a slewed angle in the middle of the A7 trunk road late at night. I really didn't have the nerve to tell them the truth: that we were looking for Noctule bats, which are quite rare in the Scottish Borders and I had piled on the brakes and leaped out of the car because we heard one. Not quite a Highway Code manoeuvre!

A couple of years ago I was asked to carry out bat surveys of a large number of primary schools in which it was planned to do extensive work so the local council needed to confirm that no bats were present (owing to their legal status as European Protected Species). The first stage of such surveys is usually a site visit, to check the buildings internally and externally for signs of bats and bat roosts. The schools were supposed to be advised when I was coming but, usually weren't. So, when I walked towards the entrance of one particular school I took a deep breath and steeled myself for the usual protracted explanation about bats, bat surveys, why one was necessary etc before being allowed past the Fort Knox security system that all schools seem to have.

To my surprise I was greeted with "Ooh bats, come in, come in!". "Wow", I thought. "This is unusual." I was ushered inside and pointed out to a passing teacher with "This gentleman has come about the bat." "Oh lovely!" was the response. By this point I was thinking something was a little odd. Not only were they unusually excited about a simple survey visit but they were talking about "the bat." Singular.

I was ushered up to a noticeboard covered in drawings of bats, paintings of bats, essays about bats etc. Alongside was a photograph of a Long-eared Bat and pages from the Bat Conservation Trust (BCT) and other bat-related websites. "I've died and landed in bat conservation heaven." I thought. The photograph was of a bat which had been found above the main entrance of the school the previous week. At first I was delighted. To see a school taking such a positive interest in bat conservation is unusual and fantastic. Bats suffer a great deal of prejudice and the best way to stamp out prejudice is to start with children. Then I thought about the bat.

The bat had been found in an exposed place on the outside wall of the school, within a few inches of an entrance used several times a day by a couple of hundred children. It apparently stayed there for two days before it "decided to leave". Whether this animal had been sick, injured or exhausted isn't clear but it certainly wouldn't have chosen to stay there for two days, being stared at by lots of people if it had an alternative option. I doubt very much that it "decided to leave". Perhaps it was eaten by a Magpie or other predator or perhaps it fell from the wall, to be picked up by a passing cat. Whatever happened could have been prevented, if someone had stopped to think "is this wild animal behaving naturally" and sought advice from BCT or the SSPCA. I suspect the kids who had researched the bat, drawn paintings of it and created a display about it would be rather upset if they learned that, whilst they were doing this, it was starving to death or being eaten.

A photo of the school bat, taken by a parent and enthusiastically bluetoothed to me from her phone.

Annoyingly we did a load of night-time surveys in the hope of finding a roost on the premises and never found any evidence. Wherever it came from, it wasn't the school.

If you find a bat and need help, advice or information contact the BCT Bat Helpline:

If you find a strange human or inquisitive copper during a bat're on your own.

My website: