Wednesday, 17 August 2016

CCTV for bat surveying and monitoring

In my work as a wildlife photographer I have met many bat specialists and have often sympathised with the amount of antisocial night work involved in surveys. As my background is in physics and engineering, I have always found technology exciting, and have combined my interests to develop a portable CCTV system for bat roost monitoring that can reduce the need for human presence during emergence and dawn swarming surveys or bat monitoring near roosts.

 Barbastelle bats dawn swarming

The portable system I have developed works well in woodland, but can be used in buildings or caves. If mains power is present, there is even more flexibility and the possibility of obtaining HD quality videos. With power and internet availability it is even possible to view remotely.
I have used trail cameras for many years as a way of establishing the presence of wildlife, and reducing the time spent looking for it, but became frustrated with the lack of flexibility and the generally unsatisfying image quality of night videos. This led to me researching CCTV as a method of wildlife monitoring. In order to test out systems in natural environments, I joined Natural England on Dartmoor as a volunteer.
The possibility of using a CCTV system for bat monitoring was always in my mind and it became apparent that, as there was no power, internet or suitable mobile phone signal in the study area, I would have to develop a portable CCTV system that could work reliably and withstand the uncertain weather in a Dartmoor woodland.
Portable CCTV systems for wildlife are not common, except in the large expensive forms used in major projects, so I had to start from scratch. Although the basics of a CCTV system are straightforward, consisting of camera, recorder and power source, finding suitable, reliable equipment is not easy. Small details can mean the difference between success and failure, but I did eventually achieve success.
The Natural England team at Yarner Wood on Dartmoor are part of the Moor than Meets the Eye project, and I was interested to discover that, as part of the project, the Woodland Trust was carrying out research on Barbastelle bats in the Bovey Valley with a PhD student from Bristol University. Luckily the team were interested in my CCTV system and willing to allow me to test it alongside their research. In addition to the CCTV camera, an SM2 bat recorder was set up to identify the bats seen on video. One big advantage of CCTV is that only infrared light is used and there is no bat disturbance. All UK bat species and their roosts are legally protected and should never be disturbed in any way. The biggest advantage, however, is that equipment setup, data collection and analysis takes place during the day and does not involve night work.
One of the roosts being studied was a Barbastelle maternity roost which was within range of the CCTV camera without tree climbing being necessary. Unfortunately the day before the camera was to be set up at the end of July, the bats vacated the roost, and it looked like the CCTV project would fail before it started. However, as Barbastelle bats are known to switch roosts frequently, it was decided to leave the equipment set up until the end of September and hope that the bats would return.
The results were surprising and exciting and yielded a large number of interesting videos. Although the main colony did not return, throughout the period studied there were regular inspection visits to the roost, together with interesting behaviour that was not fully understood.  A large proportion of the visits did not appear to have calls associated with them at all.
In July and August, Barbastelle bats visited, but in September Long-eared bats were frequently seen on video, easily distinguished by the ears and the hovering flight:

The CCTV system performed reliably and gave some excellent quality videos.  The initial hope of an occasional video was greatly surpassed, despite there being no large colony using the tree as a day roost.
Because of the success of the pilot study, a more formal research project was proposed in order to study the call structure of Barbastelle bats in more detail. The research is taking place at present, using portable CCTV as before, together with two SM4 Wildlife Acoustics recorders. Because it is possible to see the bats as well as record their calls, one aim of the project is to measure how calls vary with activity. Another aim is to investigate if there are ‘silent’ visits. Because the roost was occupied by a Barbastelle colony for the first few weeks, there is an opportunity to study behaviour and call structure before and after roost occupation.
CCTV equipment costs less than bat recorders, the only major cost being in battery power for a portable system. I visit the site twice a week to change batteries and SD cards. This level of activity ensures that data analysis remains exciting and avoids the tedium of trawling though weeks of videos and bat calls. It also allows regular synchronisation of bat detectors and video recorder, both of which can drift in time.
Details of equipment and set up can be found in my book CCTV for Wildlife Monitoring (Pelagic Publishing). The book also give details of many other wildlife CCTV applications. For those less technically oriented I give courses for those willing to travel to Devon.
For further information:  (A new site under development)

Susan Young

Monday, 8 August 2016

How you can slightly adjust your life to be more bat-friendly

There are many reasons to want to help bats, not least because it’s actually very easy! British bats are crucial to our ecosystems as they can eat over 3,000 insects a night! Large flying foxes in tropical regions help to pollinate fruits and spread seeds to ensure rainforests regenerate and are sustainable. And bat poop, called guano, is highly valued and effective fertiliser. Bats are also amazing subjects to research, echolocation could offer help to the blind and a blood thinning chemical, used by a small number of species of vampire bats, has the potential to form the basis of new medical discoveries!
                One of the easiest ways to help bats is in your garden. British bats feed only on insects (some species will also eat the occasional spider), so a sure fire way to make your garden bat-friendly is to make it insect-friendly first. Plants that flower at night will attract insects at times when bats are feeding. Building a pond, making a compost heap and planting some wild flowers are also great ways of attracting insects into your garden. Wild About Gardens Week is a great way to showcase your gardening abilities and find out more about how to make your garden a bat haven. To be in with a chance of winning our plant a bat feast’ photo competition, take a photo of your plant-display and email it to any time before November 6th!
Many species of bat are put off gardens by bright artificial lights (, especially those that are shining on roosts, access points and flight paths, so reducing these may result in a higher number of bats occupying your garden. However, there are some British bat species, such as Leisler’s bats, that feed on the insects that are attracted to street lamps.
Putting up a bat box is another relatively easy way to help bats in your garden. You can buy one or make it yourself. Visit our website to find out more about installing a bat box. Some species love bat boxes, whereas others tend not to use them. It can take a few years for bats to move in, so this method of making your garden bat-friendly requires patience. You could also create linear features, such as hedgerows or tree lines. Bats use hedges as hunting grounds and as routes to follow to get to other hunting grounds. 
Another piece of advice to cat owners, try and limit the time that your cat is out when bats are out. Cat attacks are one of the most common cause of bat fatalities; it is estimated that over 30% of rescued bats in the UK have been attacked by cats. More than half of the bats that have been attacked die as a result. If a bat has been caught by a cat it will almost certainly be injured.  Even if you cannot see any obvious injuries there is a great risk of internal infection from the cat's saliva. Furthermore, cats will often learn where a bat roost is and catch bats as they leave the roost, putting a whole colony at risk. If your cat does catch a bat, please call the National Bat Helpline on 0345 1300 228. To avoid bats being killed or injured you are encouraged to bring your cat indoors half an hour before sunset and keep it in all night between April and October. If it is not possible for your cat to be in all night, bring it in half an hour before sunset and keep it in for an hour after sunset

British bats are insectivores, meaning that they feed on insects. This means that pesticides and insecticides can inadvertently harm bats. Insecticides are used in agriculture, industry and domestically and can help explain the rise in agricultural productivity in the 20th Century. However, they have been found to weaken bats’ immune systems, thus making them more vulnerable to diseases, such as White Nose Syndrome. Moreover, during migration or winter hibernation bats may have toxic levels of pesticide concentrations in their brains. This may cause bat populations to drop, which will mean that even more insecticides are required to make up for all the insects that bats would have eaten. You can help to combat this by buying organic products that aren’t made using pesticides and eliminating the use of pesticides in your personal garden.
Honduran White Bats (c) Shirley Thompson
Adjusting your purchasing habits is also a great way of helping bats nationally and internationally. Bats account for over half of the mammal species that are found in tropical rainforests. This means that bats are vulnerable to deforestation. Bats can be highly sensitive to disturbances, such as habitat destruction and/or fragmentation. For example, when a hibernating bat is disturbed, its body temperature spikes upward in preparation for escape, costing as much as a month of stored fat reserve. Not only does rainforest destruction harm the local bats, but it leads to an acceleration of climate change, which harms ecosystems and bats around the world. There are many ways that you can change your eating and purchasing decisions to help avoid deforestation, for example by switching to a diet that relies less on animal agriculture and palm oil consumption. However, animal agriculture has increased vampire bat populations, as vampire bats feed mostly on farm animals in tropical regions Another solution is to be recycled products, which require less timber.

If you would like to do even more to help bats, be sure to visit BCT’s website ( to donate, volunteer or fundraise. If you are in the UK, we would encourage you to contact your local bat group ( Outside the UK there are a number of other organisations such as Bat Conservation International, BatLife Europe (made up of a number of organisations), Bat Conservation Ireland, Bats without Borders and African Bat Conservation

by Angharad Hopkinson, BCT comms intern (@an_gary_)

Monday, 27 June 2016

The NBMP 20 years on: Still the most fun you can have in the dark.

by By Dr Allyson Walsh, Cambridge University

In the beginning
Last night I went out and counted bats. All two of them. It was a classic NBMP evening. The rain in the Welsh marches was stuck in a repeat cycle of heavy, to light to nothing and back again in the period leading up to the count. The dreary weather provoked much debate about cancelling or going ahead, but as several of us had gathered from near and far at a significant sized roost, we opted to “Carry On Batting” in the damp. We were rewarded with a count of over 200 bats from our particular building (though not through my allocated exit to count!). The twist in this particular evening was this was the first time I have been out on an NBMP count since leaving England almost 15 years ago.

Twenty years on and still going strong makes me proud. Very proud. And given it’s EU referendum month, it may be an opportune time to reminisce on the main driver behind setting up the NBMP. It was the EU. The program was designed to directly address pressure to fulfill the UK Government’s obligations to conserve bats under European Directives, in particular the EU Habitats and Species Directive, and the Agreement on the Conservation of Bats in Europe (under the Bonn Convention). Beneath the legislative veneer however lies the important point that robust information on trends in bat populations at a range of geographic scales is essential to the long-term conservation of bats.

The BCT team from the early days

Time Proof Design 
Our world is a dynamic place, and time proofing any monitoring framework is not easy.
In exploring designs for the programme, one of our main challenges was that we knew technologies would change through time, and we would need to be able to adaptively manage this over the long term. Our goal was not to conduct a Roman style census count of every single bat, but instead to be able to compare population indices across years and look for responses to a multiplicity of factors, including climate, changing over time. Consultations with key RSPB personnel and statistician Steve Langton helped myself and my colleagues Colin Catto, Paul Racey and Tony Hutson reach consensus on a sampling based strategy to minimise bias and maximise precision, using methods that were the best available to us at the time. Sometimes starting is the biggest hurdle in project development, and we were keen to see the UK lead the way in Europe.

Citizen Superheroes
As I have watched the progression of the NBMP from the other side of the pond, I have found it remarkable, that so many citizen scientists contribute to NBMP and that so many collaborators have joined in partnership to fund the program and keep its momentum going (Joint Nature Conservation Committee, Natural England, Natural Resources Wales and Scottish Natural Heritage. Bat Conservation Ireland contributes Northern Ireland bat records collated by the Irish Bat Monitoring Programme which is funded by the National Parks and Wildlife Service of the Department of Arts, Heritage and the Gaeltacht, Republic of Ireland and Northern Ireland Environment Agency). Perhaps the secret to it is in the social nature of the program. Inviting your friends over for a BBQ and bat count is certainly a unique evening’s entertainment. Or perhaps the secret is the nurturing team at BCT (notably Dr. Kate Barlow) who have continued to lead the programme, providing regular feedback to, and cherishing, volunteers. Or perhaps the magi lies with the simple mystery and love of bats. One of my future hopes is that we can quantify the social networks and wider conservation benefits of NBMP citizen science members, as I personally know many people who started out as volunteers who have carried on to invigorate local bat group bat work, initiate spin-off conservation projects, or progress into conservation careers themselves. To me, this will always remain a big success of this program, equally as important as the big data.
Allyson Walsh out with an early design detector

Back to the Future
Looking forward, where would I like NBMP to be in 20 years time? Having filled in paper forms in the drizzle last night, it goes without saying that a shift to an App based system for data recording would be a positive goal. But ultimately, rather than being the harbinger of bad or good news, I would like to see the NBMP increasingly utilized as a springboard for conservation action. Knowledge and choice gives us power. The power to make evidence based decisions and chose a different future.  It is more than likely that monitoring programs like the NBMP, designed to attain a high degree of scientific rigor in the hands of the public as well as capture and kept the attention of non-scientists, will become more prevalent in our future. And I am hopeful for this future.

My hope stems from one of my fondest memories of the NBMP. One day I received a phone call from a lady with her knickers on her head. She explained to me that she had done her washing and grabbed a pair for protection because there were bats flying around the utility room inside her home, She explained she didn’t want them getting stuck in her hair. After explaining to her that she was safe (and hence could remove the knickers from her head), and what to do about the bats, our discussion then progressed to all about bats and their conservation status. By the end of the phone conversation, she had agreed to count her bats as part of the NBMP! Probably one of the biggest impacts you can make in conservation is to influence people’s mindsets and behavior, and participating in the NBMP opens up a plethora of opportunities to do just that. So if you are wavering on whether to go out in the to do that final NBMP count of the season - please do Carry On Batting!

Thursday, 23 June 2016

The Power of Light by Neil Wyatt

As both an environmentalist and an amateur astronomer, I always take my bat detector with me when I spend a night imaging the stars. But sadly there are two things that limit the pleasure I get from my hobbies – clouds, which I can’t do much about, and light pollution. I live near the edge of a medium-sized town, and looking north there are virtually no stars visible in the orange soup of the sky. To the south-west a few factories don’t help either, but I have a wedge in the sky to the south where I can get some reasonable views and pictures. But if I want to see or photograph faint objects, I have to drive to darker skies.

When you are out bat-watching, how often do you see more than a handful of stars, let alone the Milky Way?

So, I’ve decided to try and get something done to help rescue our dark skies, and am one of a number of people championing a petition to Government asking for action to be taken on light pollution.

The petition now stands at nearly 7,000 signatures, but we need at least 3,000 more over the next few weeks if we are to get a response from the Government. Such a response will be a valuable point on which future campaigning can be built. The petition is at

As I am sure bat group members are particularly aware, light pollution doesn’t just drown out the stars. It has a profound effect on wildlife by affecting the daily behaviour patterns of many species including bats, birds and many mammals. The impacts of street lighting on moths, by attracting them out of woodland areas and making them vulnerable to predation and possibly impacting on bat feeding patterns have been well documented. I have heard blackbirds singing at midnight and seen birch trees that haven’t dropped their leaves all winter - because of light pollution!

Light pollution can also disturb the sleep patterns of humans and cause anxiety, and recent research has shown even more worrying health effects from the disturbance to people’s body clocks.

But the most striking effect is how light pollution robs us all of the magnificence of truly dark skies and the sight of natural wonders like the Milky Way.

The answer is not a ban on all lighting, but serious action to make sure the right types of light are used and in the right places. For example, new LED lights are very efficient, but their light is harder to filter out and the high blue content has a bigger impact on the melatonin levels that control the body clocks of people and animals.

Please show your support by signing the petition and passing on the message to your friends -  we have been suing thr hashtag #NightBlight, which also links to the CPRE’s impressive maps of light pollution in the UK  It’s an important step towards achieving change.

Thank you.

Further information:

Tuesday, 21 June 2016

Swanton Novers Woodland Bat Project - Sonia Reveley

An Introduction to the Swanton Novers Woodland Bat Project

Welcome to the first blog from the Swanton Novers Woodland Bat Project. Supported and funded by the Heritage Lottery Fund, the project is an exciting new venture which started this year as a collaboration between Bat Conservation Trust and Natural England.

 My role in this project is the Volunteer Coordinator. I am the lucky soul who gets to go out into the woods with a group of volunteers to collect important data which will allow us to learn how bats are affected by common woodland management techniques.

The main objectives of the project are to learn how bats use the interior of woodlands that have been actively managed, to learn how bat activity differs between the understory and the canopy, and to raise awareness about a natural heritage with help from the local community. The project will focus on Swanton Novers National Nature Reserve, an 83ha ancient woodland with a long history of active woodland management dating back to the Doomsday Book.  As I don’t want to repeat myself more information about the project can be found here -

What has been happening since the project started

Since the start of the project we have deployed static detectors three times and have carried out transect surveys throughout Swanton Novers Great Wood in Norfolk during May and June.

April transect surveys were unfortunately cancelled due to cold evening temperatures and chilly winds. For May, the transect surveys coincided with the emergence of the cockchafer beetles (also known as May bugs), which provided a feast for the serotines and noctules emerging from the woods and a feeding frenzy was observed by the lucky surveyors. Within the centre of the woods we picked up a few barbastelles and of course plenty of pipistrelles, while down in the bottom part of the woods where a few active coppice compartments are located, only pipistrelles were detected.

June transect surveys haven’t been analysed yet, but barbastelles were recorded in the top section of the woods.

We also had our project launch on Saturday 28th of May at the village hall in Swanton Novers, to which sixteen people came to. The evening started at 6pm with a talk about the project by me, an introduction to bats by Helen Miller, Woodland Officer at Bat Conservation Trust, and an insight into Swanton Novers Woods by Ash Murray, Senior Reserve Manager at Natural England. This was followed by tea and cake and a brief training workshop giving everyone a chance to listen to different bat calls.

To finish off the evening we went for a walk in the woods with our bat detectors to see what we would hear and see. On approaching the edge of the woods just after sunset we stopped to get our bearings and were treated to a front row view of serotines and noctules emerging out of the woods to feed on the insects flying around. Together with a few common and soprano pipistrelles, the bats flew above and around where we were standing for the fifteen minutes, giving everyone an opportunity to listen to the different repetition rates and rhythms, and observe the difference in size between the noctule and the pipistrelle bats. Definitely one of my top highlight moments from this year so far.

We have also recruited seven volunteers from the local community and seven volunteers from further afield. And as I write this blog we have another interested volunteer who lives in a nearby town, not too far from the woods.  Volunteers who have helped us with the transect surveys in May and June have learnt how to use a Peersonic detector and observe bat activity along the predetermined routes.  Also, I would like to say a HUGE thank you to all our volunteers for all their help.  In total, volunteers have contributed 104 hours (13 working days) to the Swanton Novers Woodland Bat project so far.

Our plans for the next few months

Thanks go to our volunteer’s hard work and time, we are on track and will continue to deploy the static detectors and each month we will do four transect surveys. A call analysis training workshop is scheduled to take place on Monday 25th of July at Swanton Novers Village Hall, so volunteers can learn how to analyse the data using call analysis software.

We have a Community Day planned for Sunday 7th of August in the woods. An ideal opportunity to learn more about the woods and how bats use the area, the day will offer a butterfly walk, minibeast hunting, a bat walk and moth trapping sessions, together with informative displays and activities. It is also an opportunity to meet the seasonal warden, who holds a wealth of information about the reserve having worked in the woods for 20 years. 

We will also be running a bat walk in August in the woods and two offsite bats walks in September. Events will be posted on the Swanton Novers webpage on the BCT website at

Looking for a project which you can contribute to

We are always looking for people to help us. There is nothing better, in my opinion, than seeing the seasonal changes within the woods. The sunset shimmering through the bare limbs of the twisted oaks, the ground covered with bluebells and wood anemone, the flush of new leaves swiftly followed by a lush green carpet of bracken and of course the rush of excitement and exhilaration when you realise you have seen/heard  a rare woodland specialist like the barbastelle. So, if you are interested and would like to join our team on a journey of discovery then I would love to hear from you and can be contacted by email at

              Sonia Reveley

Thursday, 26 May 2016

My journey through BCT

My incredible journey through the world of bats and the Bat Conservation Trust began one year ago. In May 2015 I came across the BCT website and found out the National Bat Helpline was recruiting for seasonal staff and interns. I didn’t even think twice and applied as it could be my chance to finally enter the world of animal conservation (I was then working in retail).

Having an academic background in ecology and wildlife meant I was familiar with bats but it was not until I started reading through the masses of information the website provided that I realised how utterly amazing these animals are! I find all aspects of animal biology incredibly interesting and the more I read the more fascinating bats sounded. I mean, seriously they tick all the boxes:
1) Only mammal that can actually fly which in terms of evolution is incredible!
2) Their wings are elongated fingers which is anatomically super cool.
3) Despite being relatively small they are very long lived animals (small animals tend to live quite a short life because of their fast metabolism) with some species living 40 years or more! This defies many physiology “laws”.
4) They provide many ecological services; for example in the UK all 18 species feed on insects so they are thought to be great pest controllers. They are also good indicators of biodiversity and environment health.

I could go on and on about them, I often do, but this time I will stop there (but their behaviour is really interesting and their immune system is fantastic!).

Anyway, I digress. I did get an internship with the Bat Helpline and that was an amazing experience! Most of the calls to the helpline are very positive and come from people who genuinely want to help bats or just want to know more about them. It felt great to be able to give the correct advice and information about bats to callers and dispel those common silly myths about bats. This amazing Helpline counts with the support of volunteers who kindly give up their time to help bats in need. I found that truly inspiring. Alas, all good things come to an end and my internship at the helpline ended.

Preparing welcome packs for the National Bat Conference in 2015
However, my journey through BCT did not stop there! Luckily BCT were recruiting for a temporary Conference Administration Assistant to help with the National Bat Conference (the largest conference for bat enthusiasts in the UK); after applying for that position I was accepted and started my new job in August 2015. I absolutely love organising stuff so this job fit me like a glove! For 1 month I booked in delegates, un-booked them, prepared over 300 welcome packs, sent thousands of emails and got to go to the National Bat Conference in 2015. Even though I was working during the conference I had a fantastic time and had the chance to listen to some brilliant talks about bat research and conservation. Like I mentioned before, this was a temporary position but as luck would have it, another job opportunity was available at BCT…

At the Grant Museum of Zoology for a work meeting
In October 2015 I started a full-time and permanent position as a Fundraising & Membership Officer, my current role in the Bat Conservation Trust. I really do love my job; it’s very diverse, fun and it allows me to keep raising awareness towards bat conservation on a daily basis; part of my work is to manage our social media pages like Facebook and Twitter. I also get to participate in lots of events which is a great opportunity to tell people about bats and engage them in bat conservation! A very exciting event we will be doing this summer is Gardener’s World Live, where we will be exhibiting a “garden”. The theme of our exhibition will be Urban Gardening; we want to encourage everyone to plant bat and wildlife friendly gardens and explain that even a small urban garden or green space can help bats!

Part of my job is to also inform people during events or calls how easy it is to get involved in bat conservation. There are many different ways that people can help:
- We encourage people to contact local bat groups who organise lots of batty activities
- Doing bat surveys is always a great fun and extremely important as it allows us to keep monitoring bat populations. The best thing is there is a survey for every level of experience, even complete beginners with no experience in bat surveys (and you can even do it in the comfort of your garden
- Becoming a member also helps us tremendously. Not only does joining add your voice to ours but we rely on donations in order to fund our work
- Helping us fundraise by organising an even or taking up a challenge for bats
-  Volunteer for bats!
- Record your bat sighting on the Big Bat Map
-  Follow us on Twitter, Facebook, check our website and read our blog

On a training trek in Box Hill. Did 16 miles that day!

Like I said, I do love my job and I truly believe in the work the Bat Conservation Trust is doing. So much so I am actually doing a 25km trek at the Brecon Beacons in Wales this June to raise funds for bats! If you want to know more about this you can visit my Just Giving page. I have just reached my target but every donation helps so you can still donate!
So, in a nutshell, this is my journey through BCT and it’s been an incredible one! Working for an amazing organisation, with an incredible bunch of people and speaking up for bats!

Wouldn’t have it any other way.

Andreia Correia da Costa (@AndreiaC0sta)

Monday, 9 May 2016

A history of bat conservation by Professor Paul Racey

The suggestion to prepare A HISTORY OF BAT RESEARCH AND CONSERVATION IN THE UK came from John Burton who established the Bat Project at the offices of the Fauna and Flora Preservation Society in London in 1984 and later convened the crucial meeting which led to the formation of BCT.  John’s suggestion was timely as there are still enough people around to remember the early events and the authors listed provided text. We are grateful to those colleagues in BCT, particularly Simon Mickleburgh and Shirley Thompson, who checked previous drafts. Any errors remain our own and one of the reasons for putting it onto the members’ website is to provide an opportunity for errors to be corrected or omissions rectified.

When I was a schoolboy I had to decide between biology or history. I think I made the right decision – historical research is more difficult! .

The document can be accessed by all Bat Conservation Trust members from here:

Paul Racey