THE BAT

DETECTOR The Quarterly Newsletter of Surrey Bat Group

The Bat Detector Bat Walks 2010 September 2010 Issue 58 One of Surrey Bat Group’s summer activities is leading bat walks. This year members have assisted at National Trust and Guildford Borough Council

bat walks and at Surrey Wildlife Trust’s regular “Mad About Bats” family

evening events at Nower Wood, which include an illustrated talk and a

walk.

Bat Rescues page 2 In past years Guildford Borough Council have run bat and moth evenings, “Night Life Events,” at Pewley Down, Guildford, or Riverside Park, Burpham. This year they ran two, one at each site. Pewley Down has not been particularly good for bats before but this year 45 kHz pipistrelles and serotines were seen and it is a reliable site for glow-worms. 45 kHz and 55 Bat Moth Arms kHz pipistrelles and noctules were seen near the lake at Riverside Park and Race Daubenton’s bats were seen over the river near Stoke Lock. page 3 The National Trust runs lots of bat walks in Surrey, many of them led by its own staff, but this year Surrey Bat Group members have assisted at Winkworth Arboretum, Holmwood Common, Leith Hill, Frensham Little WNS in Europe? Pond, Ankerwyke, Claremont Landscape Gardens and at the bat day at page 4 Shalford Mill. Bats seen and/or heard on bat detectors have very much fallen into the category of “the usual suspects” - 45 kHz and 55 kHz pipistrelles and, where there is water, Daubenton’s bats foraging just above the surface, putting on their ever popular display. The occasional serotine has flown over and when Claire Andrews set up a mist net at Holmwood Hungarian Common a Natterer’s bat was caught.

Rhapsody The walk at Claremont on 4th September stands out as a particularly good page 5 one. Noctules appeared overhead as Ross Baker was giving an introductory talk; then, as we reached the point where the path round the lake first enters the trees, 55 kHz pipistrelles were seen and before long Daubenton’s bats were out over the water. By the time we had almost completed our circuit of the lake, when darkness had properly fallen, we were detecting numerous Forthcoming pipistrelles – 45, 55 and Nathusius – and a serotine foraging close by for Events some while but remaining out of sight. Later Ross Baker checked his page 8 recordings and found that a Leisler’s bat had been detected too. When one of us shone the powerful torch beam out over the lake there were numerous bats on view: Daubenton’s at surface level and pipistrelles higher up almost filling the air. If you weren’t there you missed out!

1 Summer 2010 Bat Rescues

had a couple of puncture wounds which allowed air to get trapped under the skin. Ross and Lynn were able to get rid of this with a sterile needle and fortunately it no longer looks as it did in the photo below.

Derek Smith’s most notable rescue was a bat which had been handed in at a veterinary surgery in Guildford. Unfortunately no details were taken of the person handing it in or the place it was found. This was unfortunate as in the case of recovery a bat should be released where it was found. More seriously, if bat dies and is found to test positive for EBLV2 (rabies), as has been the case with eight Daubenton’s bats in Britain over the years, then anyone who has been in contact with the bat needs to be known. In this case the bat was a Daubenton’s. It was collected on 3rd Sep and for a

Leisler’s bat, photo Lynn Whitfield. couple of hours was very active. Then it went very quiet and for the next few days Derek was convinced it was near death. By the 9th it rallied briefly but it died Reports in this newsletter of Leisler’s bats being taken th into care by Ross Baker and Lynn Whitfield seem to be on the 11 and was sent off to the Veterinary becoming something of a regular feature – the first was Laboratories Agency for testing. As nothing was heard in Sep 09 followed by the second in the very next issue, from them it can be assumed that fortunately it had not Dec 09. This summer they got an orphaned young one tested positive for rabies. which they successfully reared. They eventually took it to Amanda Millar in Sussex who hosts Sussex Bat Among the bats which Martyn Phillis had in care was a Group’s “Batzebo”, the flight cage where orphaned baby 55 kHz pipistrelle which went to the Sussex young bats can practise catching insects before release. batzebo. He also had a female whiskered bat, rescued Hopefully it will become proficient at foraging for itself from a garden in Elstead. Although her condition soon enough to be released near where it was found. improved a bit in care she still couldn't feed unaided or fly, and she was eventually euthanased. It was thought Ross and Lynn also took a male 45 kHz pipistrelle cat the probable cause of the trouble was pesticide victim into care. They gave it antibiotics and it survived poisoning. Martyn’s rescues this year started off with a although with quite extensive wing damage. This means male brown long eared bat found hanging from the that it will not recover its powers of flight and so it is plaster coving in someone’s living room in a very cold now in the care of Derek Smith who has a licence to March. It perked up OK and was released after a few keep bats in long term care and will use it to show to days. people at talks. As well as the damage to its wings it

Left to right: the Sussex Batzebo, moth trap top left with a pipe allowing insects to enter for bats to catch; dome headed pipistrelle due to subcutaneous air, photos, Ross Baker; whiskered bat, photo Martyn Phillis.

2 The Bat and Moth Arms Race

The concept of the Arms Race in evolution is a well To find out how well eared moths could hear known one. Perhaps the most quoted example is that of barbastelle echolocation calls, the activity in the nerve cheetah and gazelle. A cheetah that can run faster than in a moth’s ear was measured. In the press release Dr most gazelles will be a successful hunter and survive Hannah ter Hofstede is quoted as saying, “Recording long enough to have descendants which will inherit their from the ear of a moth in the field was a real challenge parent’s speed. On the other hand the fastest gazelles but it yielded some amazing results. Whereas moths will avoid predation and will be the ones to have can detect other bats more than 30m away, the descendants which will, in their turn, inherit their barbastelle gets as close as 3.5m without being ancestors’ speed. After countless generations of detected.” survival of the fastest we have the extreme athletes we see on the African plains today. Of course running fast Analysis of barbastelle echolocation calls indicated that is not the only way to stay alive. Plants have developed they are “up to a hundred times quieter than those of defences against animals which eat them, such as other bats,” and so barbastelles are able to get close thorns, toxins etc, while animals with leathery mouths enough to hear the echoes from the moths before the and tough digestive systems have ways to overcome moths hear the calls. them. Echolocation Jamming Moths and bats are in an evolutionary Arms Race: Moth defence against bats can go beyond simple Some species of moths have ears and are able to hear avoidance in some species. bat echolocation calls and take avoiding action. In many cases this simply involves dropping to the A 2009 paper, “Tiger Moths Jam Bat Sonar” by A J ground. Bat species with quiet echolocation calls (the Corcoran, J R Barber and W E Conner of Wake Forest so called “whispering bats”) can get close to eared University, North Carolina, USA, showed that the moths before they can escape. Long eared bats are sounds made by the tiger moth, Bertholdia trigona, act whispering bats, which is why they are difficult to pick as an effective defence against the big brown bat, up on bat detectors. Their large ears enable them to Eptesicus fuscus. Mention is made of earlier research hear the faint echoes from their quiet calls. (Their large which showed that some moths, which are toxic or ears also enable them to hear sounds made by their unpalatable to bats, make warning sounds (as many moving invertebrate prey.) unpalatable insects have warning colours to ward off The barbastelle is a whispering bat and a notable moth predators which hunt visually). This was not considered specialist, as many of us have heard from Frank to be the case with B trigona as individuals which were Greenaway in his talks and conversation over the years. experimentally silenced were found to be perfectly palatable to big brown bats. (In the case of insect Stealth Echolocation defence against visual predation there is the A paper, published in August 2010, by researchers phenomenon of mimicry: some perfectly palatable from Bristol University reveals much in depth detail on insects have “fake” warning colouration. For example the barbastelle/moth relationship. “An Aerial-Hawking hover flies look like wasps and are avoided by birds Bat Uses Stealth Echolocation to Counter Moth although they have no sting. Sound mimicry was not Hearing” by H R Goerlitz, H M ter Hofstede, M R K considered to be the explanation for the sounds of B Zeale, G Jones and M W Holderied was published in trigona.) the online journal “Current Biology”. The publication is subscription only but the Bristol University press The possibility that the moth noise startled the bat was release appeared in several online news sites. discounted as it was thought that the bats would soon get used to the sound. (See www.bristol.ac.uk/news/2010/7174.html .) Researchers concluded that the sounds in some way Surprisingly the press release claims that the jam the bats’ echolocation. They found that just as the “whispering” strategy is a new discovery but bats started the feeding buzz, giving up to 200 calls per revelations from the research are fascinating. second, the moths reacted by “clicking at a rate of 4500 Genetic markers were used to identify barbastelles’ times per second. It is thought that this interferes with prey species (presumably using bat droppings but this the echolocation sufficiently to prevent the moths is not stated in the press release) and it was found they getting caught. consisted almost entirely of eared moths.

3 White Nose Syndrome in Europe?

Most readers will doubtless be aware that white nose syndrome has had a devastating affect on populations of bats hibernating in caves in the north eastern states of the USA, with over 90% of bats in some caves dying. The fungus, Geomyces destructans, grows on wing membranes and on the muzzle, the mould growth on the muzzle giving the condition its name. It was first discovered in a cave in New York State in 2006 and has since spread to nine other states and the Canadian provinces of Ontario and Quebec. Many people have worried about the possibility of WNS occurring in Europe and a paper following research in Europe was published in August this year: “White-Nose Syndrome Fungus (Geomyces destructans) in Bats, Europe” by Wibbelt G, Kurth A, Hellmann D, Weishaar M, Barlow A, Veith M et al.

Researchers carrying out routine surveys in underground hibernacula from mid February to mid April 2009 looked for bats showing fungal growth. Where fungal growth was found samples were taken by holding adhesive tape onto affected areas or by taking fur clippings from muzzles. The bats themselves were left in place.

In the case of two greater horseshoe bats found dead in the same cave in England (the only bats from the UK to feature in this study) the fungus was found to be Penicillium sp. These were the only dead bats tested. In all other cases the fungal samples were tested and found to be G destructans, genetically identical to that found in America. The bats affected were 15 greater mouse eared bats, 3 pond bats, 1 Daubenton’s bat, 1 Brandt’s bat and 1 lesser mouse eared bat. It has therefore been established that G destructans is occurring in European bats but so far there has been no evidence of mass deaths equivalent to those in America. Indeed the single lesser mouse eared bat mentioned above was found in August 2009 with no visible sign of fungal growth. It was found once more, in February 2010 in the same hibernaculum as before with, again, no visible fungal growth.

There was a report of a bat of a hibernating bat in a cave in Germany in 1984 which had fungal growth on it but the identity of the fungus was not established at the time.

What does all this tell us? The authors of the paper conclude that it may be possible that bats in Europe have a resistance to G destructans and have co-existed with it for some time. It is also possible that conditions differ in hibernacula in Europe and America and that this may be relevant. Generally, for example aggregations of bats are bigger and more closely packed in America.

Are bats in Europe going to be alright? It must surely be too early to say and caution is certainly the order of the day (see the box below).

The paper can be downloaded in full from www.cdc.gov/eid/content/16/8/1237.htm.

WNS Precautions The Bat Conservation Trust’s Batworker Bulletin 53 gives the following advice: Geomyces destructans, the fungus associated with white-nose syndrome (WNS) has been identified in a number of eastern and western European countries. If you are planning to go to an underground site in Europe, we recommend that you decontaminate your equipment and clothes before re-entering the UK. For any questions or further information, please contact Laura Dunne [email protected] or Helen Miller [email protected] .

Decontamination product suggestions: For clothes, boots and non electrical equipment: Ark-Klens'ready to use' disinfectant, £5.58 decanted into a trigger spray container, such as the Homebase value sprayer, £0.99. For hands: Hibiscrub skin cleanser, available from Boots for £7.99 (Prices correct for August 2010)

4 Hungarian Rhapsody

Not opting for small mammal trapping was something I now regret.

For some reason we had a selection of Ecotours guides and bat experts. Bob and Jude had been accompanied by the same bat expert, Sandor Boldogh, throughout but he was only with us for the Aggtelek part of our trip (sporting a Bedfordshire Bat Group T-shirt). He booked us on a tour of one of the magnificent show caves, for which the area is famous. Although there was no wildlife interest the stalactite and stalagmite formations made it a great addition to the trip. We were less enthusiastic about being taken to see the biggest book in the world but it was soon over and one couldn’t possibly complain to such a nice chap!

Mostly of course it was hardcore batting! In the day time we visited roosts in 13 churches, 8 other buildings, a flyover and 2 cave entrances. After dark we watched 2 roost emergences both from underground sites, one a natural cave and one an old mine entrance and we had 7 mist netting sessions.

A Schreiber’s bat emergence from a cave was an almost continuous stream of bats for about an hour.

From the 1st – 10th August six members of Surrey Bat Group were on a bat holiday in Hungary, in the Bükk Hills and Aggtelek National Park in the north east of the country, with some time spent over the border in Slovakia. Our inspiration was the holiday which Bob Cornes and Jude Hirstwood of Bedfordshire Bat group went on in 2009 and which was the subject of their talk to us in January 2010. Ours was basically the same trip. It was a scheduled Ecotours-Hungary trip, “Bats, Day and Night” but as we were part of a small group (there was one other participant, Neil from Geoffroy’s bats – the distinctive right angled notch Scotland, equally keen on bats as the rest of us) it felt can be seen on the edge of the right ear of the bats on very like a tailor made trip with the organisers striving the right and in the centre. to give us what we wanted. As one guide said, “I know . you guys will never be batted out but if you want to do The first mist netting was on the very first evening something different let us know.” There was some with Péter Estók as our bat expert. By the time our good incidental bird and butterfly watching but an guide, András, had driven us to the site there were two excursion we had requested to look for beavers didn’t bats in the net. One was easily removed and put into a happen because of recent flooding in the relevant area. bag but the other was in a mighty tangle. When it was On our journeys back to the hotels at night the fight to finally extricated it was shown to us first. We were stay awake was rewarded by glimpses of beech very excited when Péter announced it as an Alcathoe martens in the minibus headlights on three occasions. bat – but if only it hadn’t been the first bat! Understandably, as it had been stressed by the

5 entanglement, Péter wanted to let it go as soon as bigger roost than before. Deep guano represented just possible. He is an undoubted expert, being the first to one year’s accumulation and it was amazing to see discover Alcathoe in Hungary. He now regards densely packed masses of bats and to have the Alcathoe as more common than whiskered bat and constant fluttering of flying bats around us in the distinguishes that species pair from Brandt’s bat by smelly heat. Our bat expert for that day, Péter feeling the shape of the front of the skull with his Gombkotö, estimated that there were 1500 mouse finger. (What difference does he feel? We don’t eared bats (lesser and greater), 500 Geoffroy’s bats, know.) We would have liked to have known the and 400 horseshoe bats (greater, Mediterranean and a forearm and other measurements but as it was the first few lesser). bat we didn’t ask and also we were yet to learn how quickly he liked to work. All in all, the bat had flown before we were all really happy about it! Most frustrating.

The bat in the bag was a Brandt’s bat and this was followed by a Bechstein’s bat and a greater mouse eared bat. The latter bat was exciting at the time but we were to see many more. The following night we had more mist netting with Péter at a town park lake. Here several Daubenton’s bats were caught – and a pond bat. By now we felt ready and able to ask for a thorough examination and were very happy with our look at the pond bat which was a new species for all of us. Grey long eared bat. The broad base and emarginated tip of the tragus are distinctive, but exaggerated in this foreshortened view.

In another church we saw our only grey long eared bats whose roost site was just inside the door from the stairway to the loft. Here Péter Gombkotö climbed up into the tower timbers and somehow got down with a lesser mouse eared bat in one hand and a greater in the other and gave us an excellent master class on distinguishing the two species. They are similar in size but the greater has longer ears with 7-8 horizontal folds (lesser has 5-6), has a dark spot on the tragus tip and has a less delicate general appearance. Lesser has a few light hairs on the forehead which give it a just visible pale spot.

Part of a large, mixed species roost in a church loft.

Speaking for myself, some of the church roosts were the most impressive bat experiences. Unlike English churches those in Hungary have ceilings and lofts. In some cases the lofts have many bats of a number of species. One of the most impressive was a church in the village of Benhorvati. This was re-roofed ten years One of the biggest surprises was seeing a large noctule ago after consultation with bat people and now has a roost in a concrete flyover (above) and hearing about

6 the noctule roosts which occur behind concrete panels He had a pragmatic approach to checking behind on city blocks of flats. (We know the species as a tree shutters of lake-side houses – knock on the door and if dweller.) someone’s in ask permission - if not then look anyway. One Leisler’s bat was caught in a mist net, with a This way we had fine views of two northern bats number of noctules on the same evening. A few which were behind different shutters on the same serotines were found in lofts with other species. house. Under the eaves of a nearby house, which also had no-one home, was our only whiskered bat. With Stefan we visited a remote café where he knew of a parti-coloured bat roost. Unfortunately the roost had moved – we saw common pipistrelles but our only view of parti-coloured was a silhouette flying overhead with a rather serotine-like echolocation call on the detector.

We certainly saw a very good selection of bats so really we shouldn’t worry about the ones that got away. We are only human, however, so it was galling to learn that a certain Jon Hall, the only person in the world to have seen a thousand species of mammals, was in Hungary about a week before we were and at a mist netting session, almost certainly at the site of our first one, saw a greater noctule! See the report on his website www.mammalwatching.com/Palearctic/palearcthungar y.html . Northern bat with blonde highlights Text and photos, Derek Smith Our bat expert in Slovakia was Stefan Matis. With him we saw several large lesser horseshoe bat roosts and Schreiber’s bats in the hand during mist netting.

Look no gloves! The lesser (left) and greater mouse eared bats were remarkably docile in Péter Gombkotö’s hands.

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Forthcoming Events

Meetings – this season’s meetings will once again be at the National Trust’s Dapdune Wharf, Wharf Road, Guildford. Wharf Road is off Woodbridge Road, between the Methodist church and the southern side of the cricket ground. Go to the end of Wharf Road, through the National Trust gate on the right, along a roadway over speed bumps to the car park on the left. We meet in the tea-room there. All meetings start at 8pm.

Surrey Bat Group is very grateful to the National Trust for providing this venue.

Thursday 21st October – AGM: our traditionally informal review of the year. We have also invited a representative from the Bat Conservation Trust to discuss the new forms of agreement they are proposing between the BCT and individual bat groups, to replace the current affiliation system. Further details can be found at: http://www.bats.org.uk/pages/resources_for_bat_groups.html. As the group needs to decide which form of agreement to take up by the end of 2010, we would especially encourage attendance to give us your opinion.

Surrey Bat Group has been fortunate in being able to arrange talks on two of the lesser known British bats this season:

Thursday 18th November 2010 - “Britain's Forgotten Bat: Current data on Nathusius' pipistrelle in the British Isles” – a talk by Jon Russ, the authority on the species in the British Isles.

Thursday 16th December – “An integrated approach to the studying the conservation biology of the grey long eared bat, Plecotus austriacus” – a talk by Orly Razgour and Erika Dahlberg from Bristol University.

Other Events Bat Box Checks will take place during the autumn.

Underground hibernation site checks will be carried in Dec, Jan and Feb. In order to keep disturbance to a minimum numbers of people are restricted and will be limited to bat group members.

For more information on Bat Box and/or Hibernation Site checks contact Ross and Lynn: e-mail: [email protected], phone: 01932 842636.

Surrey Bat Group, c/o Surrey Wildlife Trust, Please send any contributions for School Lane, Pirbright, Woking Surrey, GU24 0JN the Surrey Bat Group newsletter or Phone 01483 795440 subscriptions to: Derek Smith, Surrey Bat Group website: 20 Carroll Avenue, Merrow, www.surreybats.org.uk Guildford, Surrey, GU1 2QJ. Surrey Bat Group gratefully acknowledges the continued help from Surrey Wildlife Trust, in the form of facilities and materials, in the production of the newsletter. Views expressed in The Bat Detector may not be those of the Surrey Bat Group or any other organisation. All uncredited articles by Derek Smith. Surrey Bat Group Chairman: Ross Baker, Secretary: Lynn Whitfield, Treasurer and Newsletter Editor: Derek Smith.

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