Mammals – Page 5 – Hoopoe

Beaver Trust: Q&A with Eva Bishop

Eva Bishop, Communications Director for Beaver Trust, recently took the time to talk to us about the important work the charity is doing to help communities welcome beavers back to Britain.

In this thought-provoking conversation, we discuss some of Beaver Trust’s upcoming projects, how the Covid pandemic has affected them as a charity, and share different ways to get involved in beaver conservation within Britain.

1. Firstly, can you tell our readers a bit about the Beaver Trust and its main aims?

Our overall mission is to restore Britain’s rivers and wildlife with beavers. We were not in fact established as a single species charity, but as a small crew wanting to build climate resilience for people and wildlife – yet we see the potential for rapid and restorative action that beavers offer. If you take a look at a map of British waterways it depicts an expansive system of veins carrying the lifeblood of the country. Then imagine huge swathes of that being given greater space for nature, becoming living wetlands and water storage systems rather than drained, polluted, straightened ditches. Beavers are our ally here so we are working collaboratively with a range of organisations and of course landowners to support their return.

Beaver Trust’s core work involves convening real conversations in order to make good decisions on national beaver policy and a supporting management framework, finding engaging ways to achieve outreach and education on learning to co-exist with beavers again, and of course supporting many beaver projects on the ground. Our national aim must be to move beyond enclosed projects wherever possible so that beavers can once again become part of native wildlife fauna and work across whole catchments to reinstate biodiversity and healthy ecosystem function.

2. There is a lot of contention between some landowners and conservationists around the subject of beavers, particularly when it comes to reintroductions. Do you find that misinformation and prejudice are significant challenges in the case of this species?

Where misinformation and prejudice exist it’s always unhelpful. However, I think the existence of conflict can be overplayed with beavers and our experience has been one largely of cooperation and collaboration.

Beavers and their impacts aren’t always beneficial to the surrounding land use, we’re very clear about that. Where contention does arise it can often be overcome through better information and knowledge. Well practiced management techniques are being successfully used across Britain, with the right experience and resources there is no reason for these not to become second nature like tree protection against deer for example. Beavers are reestablishing already, but we have an opportunity to target areas for new wild releases that are less likely to cause conflict and instead achieve greater benefits for society and wildlife. That’s something we are collectively all working towards, to minimise conflict.

There is always room for misinformation – hence our core strand of work around communications and education – and there is still work to be done engaging a broad audience in key conversations around beavers (such as farming, angling, flood-banks and the appropriate use of lethal control), ensuring broad diversity in all conversations and that everyone is heard. There is a lot of good research available on the impacts and effects of beaver reintroduction across Europe, not to mention the research within Britain as well. Management is also well-established and now requires government resources to expand nationally alongside training and communications, so that we can offer a swift response to any anticipated, perceived or felt issue.

Prejudice is harder to tackle, as is human nature’s aversion to change, but we always aim to put forward a transparent view of beaver impacts including challenges and invite inclusive debate across our work. But as I said, Beaver Trust’s experience in England to date has been a pretty positive one with the landowning and farming community.

North American beaver on lodge by Ben Goldfarb

3. A core component of your work moving forward is set to focus on river buffer zones – allowing nature to recover and regenerate around river banks. Can you tell us more about this?

Yes, and it links directly to the previous question. If we want beavers to achieve all the good flood and drought mitigation, water filtering and biodiverse habitat restoration we anticipate, they will need space to operate. Their dams and canals can revert streams and smaller rivers into meandering wetlands, however, depending on the location this could quickly cause issues. In a sense, we need to make our rivers fit for beavers (and all other life that should exist there), without placing further burden on farmers trying to do the right thing and produce affordable food.

The key is space for nature. Stepping back from the margins and allowing the naturally high biodiversity that should exist there to thrive. Beaver Trust is therefore working in partnership with leading environmental NGOs on a programme for riparian buffer zones along whole catchments. We need a greater vision than a small strip of river bank, and are aiming for 10-20m+ zones, but it could even mean whole floodplains are set aside for natural processes.

Farmers will then be paid for nature’s recovery and we’d like to see farm clusters able to apply, allowing greater scope for whole catchment restoration and connected nature corridors. For the programme to succeed and feed into ELMs we need a simple payment mechanism and not just another layer to add to the farmer’s list of environmental expectations. We need a broad partnership, including Defra, to think systemically so that it becomes easier for land managers to make good environmental decisions without hidden costs to their operations.

If we allow rivers the space to find their natural course and re-establish meanders, scrub and woodland to naturally regenerate, beavers to bring back freshwater habitat and increase species abundance, then we will start to see real resilience along our river network ready to help us as climate pressures hit harder and stronger.

We hope to see a bold and ambitious government strategy for beavers, but given their catchment-scale impacts we should be thinking systemically with related policies. The great thing about river buffers is that it could take relatively little land out of production – but these edges are where all the great biodiversity happens. So it’s a win-win for conservation and farming if we make it easier and practical to sign up.

4. Are there any other big projects that the Trust is going to be working on in the near future?

Our main policy campaign this year will be river buffers, working in partnership with the National Trust, Rivers Trust and Woodland Trust. As part of this we are working on a follow-up documentary film to the award-winning ‘Beavers Without Borders’ (2020) that explores the challenges and opportunities for river buffers, interviewing experts on a variety of areas including farming, angling, public access and biodiversity. But we will also continue our core policy ambition convening broad stakeholder working groups on the English Beaver Strategy, which the government is set to consult on this summer.

In the restoration department we are supporting a groundbreaking community-led beaver project where a group of local landowners and residents are looking to reintroduce beavers as a flood mitigation strategy along the whole catchment.

Beaver Trust has also recently been awarded the call off contract for the beaver management framework in Scotland by NatureScot, so we’ll be gearing up for a busy season at the end of the year. Working alongside landowners experiencing conflicts particularly in prime agricultural areas and looking towards long-term mitigation strategies. This can range from ecological advice, tree protection, dam and burrowing mitigation, to translocation as a last resort. In collaboration with the animal care and veterinary team at Five Sisters Zoo, beavers are health screened and rehomed to licenced projects elsewhere in the country.

Our communications and outreach team is working hard across a number of projects, including The Lodge Cast podcast series, radio and other media. We also have several education initiatives under way but one particularly exciting partnership is for a new beaver enclosure and educational learning hub at a major tourist attraction in the South West. The key driver of this project is improving nature connection with children from socially and economically deprived backgrounds, and people with reduced mobility and sensory and cognitive disabilities. We have not yet secured funding for this project so cannot say further than that at present but it exemplifies Beaver Trust’s ambition to educate and connect people beyond wildlife enthusiasts with the joys that beaver wetlands offer.

5. The Covid pandemic has had a huge impact on individuals and organisations. How has the Beaver Trust been affected over the past year, and how have you dealt with these unforeseen challenges?

It’s been a genuinely interesting and challenging time to be part of a new charity: Lockdown arrived while Beaver Trust was really getting its roots down, there was no furlough option for us at the time as we were so new, plus we were a very small team and some of us had the challenge of home education to navigate (torturous for both teacher and pupil)!

But it has made us a really strong and resilient team, given our remote locations. I think one of the great strengths of Beaver Trust people is their wholehearted approach to work: Real conversations, emotional wellbeing and individual authenticity is encouraged and, for us, it works well. It also helped immensely to have a powerful passion for nature restoration and climate action shared within the team, enough to keep everyone motivated, and to have such incredible support for beavers from the public. They are already a much-loved animal and as such we’ve received reams of very humbling offers of voluntary support from all sorts of highly experienced individuals. We are grateful for every single one.

6. Thank you so much for your time in chatting to us. One final question: for anyone interested in getting involved in beaver conservation within Britain, how would you suggest that they go about this?

It’s a great question and I’d start by saying it’s time to break the system: forget career silos, land and wildlife needs ALL of us – it is everyone’s countryside, rivers are everyone’s source of freshwater and wildlife should be part of everyone’s mental health and wellbeing whether through paid employment, voluntary time or new cultural norms. To use a small example, how do we make litter picking fun? Anyone can care for their local patch and help conserve it. I recently saw a wine bottle used in the construction of a beaver dam, something we can avoid by everyone taking part.

But I also think the conservation sector can be quite intimidating and packed with such expertise it’s hard to infiltrate, so I’d encourage people to follow their interest and speak up, even if you’re not sure you tick every box. Within beaver restoration, specific roles will emerge within charities and across communities as wild populations expand, specific training programmes will be available (for example beaver management through CIEEM), keep an eye out for new job opportunities with Beaver Trust, Wildlife Trusts, Woodland Trusts and others.

Another idea would be to join in with some citizen science on collecting information on beavers and river impacts. This doesn’t need to be specific to Beaver Trust either – there’s the Freshwater Habitats Trust, or the Mammal Society which has a mammal tracker app, all of which could help support wider conservation work.

If you’re already in employment, why not talk to your company about funding nature’s restoration and helping scale the impact of nature restoration charities. One of the biggest challenges to conservation is the funding and resources to expand operations.

On a purely fun level, Beaver Trust also hosts regular outreach activities like May’s poetry competition, last year’s photography competition, the monthly podcast, online quizzes and various other celebrations, so please get in touch and join in. Write us a blog and we might be able to publish it on our website. The more these communications are shared, the more people will understand what a beaver is and be accepting of its arrival. Conserving nature as a whole will benefit all the species that rely on it, including humans.

You can find out more about the Beaver Trust from their website and by following them on Facebook and Twitter.

To learn more about the Beaver Trust’s conservation projects, you can read the Introducing: Beaver Trust article included in the Spring 2021 issue of Conservation Land Management magazine. In this article, Eva Bishop discuss how the Beaver Trust came to be, what it is trying to achieve, and the exciting projects it has been involved in.

An Evening at Sharpham – Bat and insect survey

The lengthening evenings of late Spring or early Summer are an ideal time for an evening wildlife walk. Now the vegetation has become more lush and the air has become warmer, the insects form in thicker clouds and the bats are now on the wing.

The Sharpham estate is a 550-acre area which runs alongside the River Dart just outside Totnes. This historic landscape is home to the Sharpham Trust, an educational charity whose Wild for People project aims to rewild areas of the estate and enhance biodiversity in the region. To read more about the history of the Sharpham Estate and the launch of their Wild for People project, click here.

A few of us from NHBS walked up to the Sharpham estate where we met a group of Ambios’s conservation volunteers and trainees for an evening wildlife walk. We brought a selection of bat detectors with us and explained the differences between our most popular professional detectors. We distributed any active bat detectors among the volunteers and showed them how each type worked. We then left the farm just as dusk was settling with detectors armed and ready.

As we wandered the footpaths and fields of the estate, we watched several Noctule and Leisler’s bats commute high above the fields, along with some Common and Soprano pipistrelles zipping along the hedgeline foraging.

We then cut across a field to a dead tree where NHBS Wildlife Equipment Specialist Josh had previously set some insect bait traps. The traps were baited with a mix of banana and beer and had been set in the hopes of catching saproxylic beetles emerging from dead wood.

Josh has also been monitoring the beetle diversity of Sharpham through a series of pitfall traps placed across the estate, although prior to our walk they had unfortunately been closed due to heavy rain. Unfortunately no beetles were found in the traps this time, but we did spot a variety of species scurrying along the field and forest paths including Anchomenus dorsalis, Dromius agilis and Staphylinus dimidiaticornis, along with the very common Nebria brevicollis (gazelle beetle) and Pterostichus madidus (black clock beetle).

Once it was much darker, on our way back up to the farm, we also had the pleasure of listening to the alien-like call of a sitting Lesser Horseshoe bat that was perched just meters away from the group. It made for an exciting end to the walk and we hope to detect even more bat species through passive detector recordings.

See the full range of bat detectors and insect survey equipment on the NHBS website.

To find out more about Ambios and the work of Lower Sharpham Farm, please visit https://www.ambios.net/.

Mammal Society: Q&A with Stephanie Wray

The Mammal Society is a charity dedicated to the research and conservation of Britain’s mammals. By surveying, monitoring, researching, and sharing information about the state of mammals, it contributes to conservation efforts to help maintain these species.

We recently spoke to Stephanie Wray, the new Chair of Mammal Society, who kindly took the time to answer some questions about her background, her ambitions for the charity, and some ways in which you can get involved and support mammal conservation.

1. First, could you tell us a little bit about the Mammal Society and the important work that it does?

The Mammal Society is a charity which works towards the conservation of British mammals based on sound science. We were started in the 1950s and have always had both a strong academic member base of the ecologists and natural scientists who study our wild mammals, but also a fantastic body of amateur naturalists who are fascinated by mammals and willing to give up their free time to learn more about them and help their conservation in practical ways. Over time our membership has grown to include, for example, ecological consultants who work with protected species, protecting them from development, and many others who just love mammals. Increasingly we are benefiting from support from members of the public who, while they may not be able to devote time to practical projects themselves, care deeply about the British countryside and our iconic mammal species and want to help us to help them. At the moment we are developing exciting projects looking at the conservation of mountain hares, our amazing native hare which turns white in the winter and which may be threatened by climate change, and the harvest mouse, a species of traditional farmland as small as a two-pence piece and increasingly threatened by the way we manage our countryside.

Mountain Hare, Cairngorms by Sorcha Lewis (Mammal Photographer of the Year 2020)

2. From your PhD on brown hares in the 1990’s and a post-doc on Livingstone’s bat on the Comores, to your role as past president of the CIEEM and, most recently, your position as director of Biocensus and founder of specialist consultancy Nature Positive, you’ve had an incredibly fascinating and influential career so far. What attracted you to the position of Chair of the Mammal Society?

I’ve always had a soft spot for the Mammal Society, since my first Mammal Society conference in 1989. It’s where, a couple of years later, I presented my first scientific talk on the results of my PhD research and where I met many other mammal enthusiasts who have remained lifelong friends. Many of the Society’s members, professional and volunteer, have helped me with my research over the years, turning up in fair weather or foul to help me catch and radio-collar mammals to learn more about their habits, collect samples of dropping and other ‘glamorous’ tasks. So I want to be able to give something back, to make sure that the Society continues to grow and acts as an effective, science-backed voice for the conservation of wildlife in the UK. Our members have a huge amount of knowledge and experience and I want to make sure that we can leverage that to have our voices heard and deliver the right outcomes for conservation.

3. Unusually for an ecologist, you also have a Master’s degree in Business Administration. Do you think that marketing, economics, and the social sciences in general have an important role to play in ecology and conservation?

Well, you have done your research – I do indeed! We hear a lot about the bad things that businesses do, but the economic reach, innovation and entrepreneurship of industry can also act as a huge power for good. Businesses are starting to realise that their entire operations depend on biodiversity and that working to protect the natural world is not just a philanthropic exercise, it’s sound business sense. Sometimes how a business affects the environment is very obvious (they may use a lot of water or harvest a wild species) but in many cases it is hidden deep in their supply chains. Let’s say that you are a manufacturer of oat milk. You will have a great narrative around the climate impacts of your product compared to dairy milk, soy and almonds – but what about the biodiversity impacts? If the oats you buy are grown at a factory scale, removing hedges and ploughing up to the field boundaries, with the addition of lots of artificial fertilisers or pesticides, then you will have undone all those climate benefits through your impacts on nature – and the decline in the harvest mouse population would be an indicator of that. Now that is not just a concern to the Mammal Society – it’s a risk to your business in terms of future costs (as the environment becomes more degraded then we lose soil fertility and pollinator species, and yields will fall) in terms of your reputation (we’re drinking oat milk in the first place because we care about the environment) and in terms of your ability to attract investment (the institutional lenders don’t want to be on the wrong side of the next ‘palm oil’ issue). Under that kind of pressure, businesses can be incredibly flexible and develop new approaches, like regenerative farming, which can represent a win-win – a premium product for them, a healthier environment for everyone.

4. Taking on the role of Chair of a charity during a global pandemic must be an exciting yet challenging prospect. What are your hopes and ambitions for the charity over the next few years?

It is certainly an exciting time to take on a new role. Particularly during our first ‘lock down’ in Britain last year I think we all really appreciated our limited time outdoors and took time to enjoy those short nature ‘snacks’. For some that meant spotting wild goats or deer in the car-free streets, for others it may have been a grey squirrel or urban fox in the garden. My hope is that as we recover from the pandemic we don’t lose sight of that link to nature, and that as society moves forward it will be with increased understanding of and respect for the way the natural environment supports and underpins everything we do. My ambition for the next phase of the Mammal Society’s life is to really raise our profile to that of a household name alongside larger charities such as RSPB and WWF. I want to make sure that we develop our communications strategy, and through our website, publications and social media engagement, reach a wider audience and raise the profile of British mammals and their conservation in line with our charitable objectives. I want us to continue delivering the highest quality of scientific research and to proactively engage with government and the media on mammal conservation and management issues to contribute to the delivery of evidence-based policy.

Female Muntjac by Keith Elcombe (Mammal Photographer of the Year 2021)

5. As stated on your website: Britain is now recognised as one of the most nature-deprived countries in the world. Are you broadly optimistic about the future of mammals in the UK?

I think we have to be; the only viable option for human society is to live in harmony with nature. This year is a hugely important one for nature with the COP15 meeting in China in October on the post 2020 Global Biodiversity Framework, and the related COP26 meeting on climate change in Glasgow in November. These will be decisive in setting out international approaches to protected areas and sustainable use of the commodities we harvest from nature. Here in the UK, we have clear commitments arising from our exit from the EU, in the government’s 25 year environment plan, and through measures such as mandatory Biodiversity Net Gain in the forthcoming Environment Bill. All the pieces are there, we just need to commit to putting them together into a coherent protection framework. One quarter of British mammals are currently at risk, but it isn’t too late to bend the curve on extinctions and watch our biodiversity flourish again.

6. Finally, for any of our readers who are wanting to get involved with mammal conservation in the UK, what are the most important things that they can be doing right now?

Firstly (obviously!) have a look at the Mammal Society’s website (https://www.mammal.org.uk/support-us/) and you will find all sorts of things you can do to help from sending us records of mammals you have seen to organising a bake sale (hedgehog cupcakes, anyone?). In your day to day life, here are a few things you might try to help mammals.

Garden with nature in mind. If you have a garden, try to leave a wild corner with food for wildlife particularly in the autumn and winter. An open compost heap if you have space is helpful to invertebrates, reptiles and small mammals (but don’t add any cooked food!) If you have a pond, make sure the sides are not too steep or add a ramp to make sure thirsty creatures don’t fall in and drown. Consider leaving food out for hedgehogs (cat food, never milk) or badgers (they aren’t too fussy!) if you are lucky enough to have them. Leave small gaps under fences to make sure hedgehogs and other small mammals can move around. If you don’t have a garden, a window-box or a pot of herbs on the doorstep can provide a source of food for pollinators and contribute to biodiversity.
One of the biggest threats to nature is how we manage the countryside and as consumers we can all send a message about what we want agri-business to do. Choose products wisely – is there embedded destruction of the countryside in that breakfast cereal? Write to the supermarket or the manufacturer and ask them how they manage their impacts on biodiversity – both directly and through the ingredients they buy in.
Write to your local MP and ask them what they will be doing to make sure that even removed from the EU’s strong environmental legislation, Britain will be a leader in environmental protection. The Wildlife and Countryside Act, which is the key piece of legislation for protecting mammal species such as bats, otters and dormice, is under review this year. Ask your MP to vote to retain and add to the strict protection we have for some mammal species and to prevent it being watered down.
And most importantly – just go out there and watch mammals. I may be biased, but for me there is nothing better than being out in the countryside early on a spring morning watching the hares chasing around and knocking seven bells out of each other. You might like to stay up late watching badgers or bats, or enjoy the crazy antics of a squirrel on a bird feeder. It’s important that we engage with nature and encourage our children to do the same. If we don’t see and understand wildlife, we won’t fight for it. And, trust me, we need to fight for it.

You can find out more about Mammal Society from their website and by following them on Facebook and Twitter.

Devon Badger Group: Interview with Chair, Jenny Pike

Formed in 2010, the core aim of the Devon Badger Group is to protect badgers and their habitats. Funded by membership, donations and fundraising events around Devon, they run a free 24/7 helpline for sick or injured badgers and other badger-related issues.

We recently had the opportunity to chat with Jenny Pike, Chair of the Devon Badger Group, about the group’s important work, their successes and challenges, and how Covid-19 has affected their lives over the past year.

Firstly, can you give us a brief introduction to the Devon Badger Group and your role within the group?

My name is Jenny Pike and I am Chair of the Devon Badger Group (DBG). In a nutshell, the purpose of the DBG is to protect badgers and their habitat, record their activity, educate and further the public’s understanding of badgers, and to encourage tolerance, appreciation and respect for all wildlife. We also work with the police and RSPCA, and respond to any activities that could be detrimental to the welfare of badgers.

What do you consider to be the main threats to badgers in the UK?

Sadly there are many threats to badgers and, despite gaining legal protection in 1992, badger persecution is on the increase. In England, one of the biggest threats badgers face is the government licenced badger cull. Since the cull began in England in 2013, a total of 140,991 badgers have been killed, 30,345 of which have been in Devon.

Other serious threats are housing developments where, even if setts are protected with appropriate mitigation measures, a significant amount of foraging ground can be lost. New roads can also impact badgers if appropriate badger tunnels are not installed or are installed in the wrong place. Hunts sometimes block badger setts to prevent foxes escaping down them and, as already mentioned, illegal badger persecution is on the rise along with other forms of organised wildlife crime such as dog fighting.

I am sure everyone will have seen many badgers dead on the side of the road. No one knows exactly how many badgers are killed by vehicles each year – one estimate has it at 50,000.

What are your main goals as a group?

Our main aims are to protect badgers, their setts, and their habitats. But we feel that if we can increase the public’s understanding of badgers and dispel some of the myths, people will feel more encouraged to protect them. Sadly, most people we talk to have never seen a live badger. This is why, whenever we are contacted by members of the public who think they have badgers visiting their gardens, we offer to put up a trail camera so they can actually watch visiting badgers go about their business, which is usually looking for earthworms and other invertebrates. This often has a very positive effect and has changed people’s view of badgers.

What would you consider to be your greatest success as a group?

In 2019, through some very generous grants and donations, the DBG was able to fund two members to train to become licenced lay vaccinators. I was lucky enough to be one of them. Since then, we have worked in collaboration with the Somerset Badger Group to vaccinate badgers in Devon and Somerset, which has allowed us to gain valuable experience. We hope this will continue and expand in the future.

Covid-19 has caused difficulties and presented issues for all of us. How has the pandemic affected the work that the DBG does, and have there been any unforeseen positive effects?

On the positive side, it is possible that less cars on the road in the first lockdown resulted in fewer badgers being killed or injured. Spring is when cubs are still dependent on their mums and when most road casualties occur, and so this would have had a significant effect on badger cub survival rates if mum survived to successfully wean them.

On the negative side, although we were given permission by Devon and Cornwall Police to continue to rescue injured badgers on animal welfare grounds, we were not able to carry out sett surveys, monitor setts which had been targeted previously, or visit homeowners who had contacted us for advice on badger issues. We were also unable to carry out our regular fundraising activities which, in normal circumstances, not only provides much needed funds, but also gives us an important opportunity to engage with the public and answer their questions. This is something I personally have missed a great deal as there is no substitute for face-to-face communication.

Having said that, we have been able to continue our most important work by keeping in regular contact with our committee and members through electronic communication, Zoom and Teams meetings. This has had an unexpected benefit of not only reducing our carbon footprint, but also allowing us to engage with our members across the whole of the county (internet permitting!).

You mention that you sometimes use trail cameras in some of your work – could you tell us a bit more about this?

We use trail cameras extensively in the DBG and they have been invaluable in proving setts are active in cases of sett disturbance and sett blocking. They have also been used to great effect when showing school children the wonders of a shy nocturnal animal they would never usually see. I have been using a number of cameras recently on a beaver enclosure to ensure the badgers and other wildlife are able to move freely in and out (except the beavers of course!). I also have my own trail camera and I still maintain that it was the best Christmas present ever. I use it all the time for monitoring the wildlife in my own garden in Plymouth.

In May of last year, the government announced that they hope to shift away from culling and towards badger vaccination to help in the fight to eradicate bovine tuberculosis (bTB) in England. What does this mean for the group and will the DBG be involved with badger vaccination programmes?

The Devon Badger Group is opposed to the badger culls but, of course, recognises the distress and hardship bTB causes for farmers, their families and their animals. We sincerely hope that the government honours its commitment to progressing a vaccine which is much more likely to provide real benefits to farmers and their cattle than the current bTB strategy.

Controlling the spread of bTB is a complex issue that will need a raft of measures to tackle, but they must all be backed up by sound scientific evidence. The role badgers play in bTB transmission is still not fully understood: what limited studies have been carried out to determine the prevalence of bTB in badgers have concluded that approximately 4.5% of badgers tested are infected with bTB. It is now accepted that the vast majority of bTB transmission to cattle is from other cattle, but this was previously unclear due to the poor accuracy of the routinely used skin test. This skin test has been found to be around 50-80% accurate, resulting in up to 1 in 5 infected cattle remaining undetected in the herd to pass on the infection.

With this in mind, and the fact that bTB can live in soil and slurry for many months, there is enough doubt on the role badgers play in disease transmission to compel the government to re-evaluate their bTB strategy for the benefit of farmers and the whole farming industry.

We welcome the government’s commitment to replace badger culling with the more humane badger vaccination and we hope to be involved in any future badger vaccination initiatives. We would be very happy to work with and support Defra and other organisations in delivering on this new initiative until a more effective cattle vaccine can be deployed.

It is obvious that you are very passionate about badgers and love them dearly. What is your favourite fact about badgers?

As large as they are, their main food source is earthworms and they have to delicately pull them out of the ground without snapping them!

How can people help protect badgers and get involved in their local area?

Please keep an eye on your local area, especially if you have any setts near you. If you would like help on identifying signs of badgers, we would be more than happy to help (Covid-19 permitting).

Report any suspicious activity around badger setts to the police and do also let us know. Please also report dead badgers to us – in spring this is important if it is a lactating female with dependent cubs below ground.

Please consider joining the Devon Badger Group. We are a small but active group but have one of the largest and most rural counties in England to cover.

We can be contacted at devonbadgergroup@gmail.com and on our 24/7 helpline number 07710 971988 or I can be contacted direct on 07791 490572.

6th International Berlin Bat Meeting 2021

The 6th International Berlin Bat Meeting was held online from 22nd–24th March 2021 and consisted of a series of varied and fascinating live lectures based around a timely theme: ‘The Human Perspective on Bats’. Over the three days, speakers from around the world spoke on topics such as bat coronaviruses, bat health, human interventions, bats in anthropogenic habitats, ecosystem services, conservation marketing and citizen science.

The first day of the conference began with a keynote talk from Prof. Felix Drexler (Institute of Virology, Charité Berlin) who spoke about emerging viruses with a focus on bats and SARS-CoV-2. He began by relating the fact that most (around 60%) of human pathogens have a zoonotic origin and that several notable animal-borne diseases have originated in bat hosts (eg SARS 2003, Ebola), although it is currently still debated whether bats are particularly prone to becoming reservoirs of zoonotic pathogens or whether they are just very diverse and numerous in comparison to most other mammals.

It is a constant challenge to predict where future diseases or pandemics may arise, although important factors appear to be Exposure (whether humans have close contact with the species), Ecology (aspects of the animals’ behaviour or ecology that are favourable for the maintenance and transmission of pathogens) and Evolution (as pathogens are more likely to cross species boundaries if species are genetically and antigenically related).

Moving forwards, Prof. Drexler suggested that better surveillance is required to respond to cases of zoonotic spillover, as an early response is vital in preventing future pandemics. This is particularly important in peripheral healthcare settings such as where small numbers of cases initially crop up in developing countries.

Later on in the day, Dr. Jon Epstein (EcoHealth Alliance, USA) continued this theme with a talk that looked at the interconnectedness of animal and human health. He stated that, although the exchange of microbes between animals and species is normal, many aspects of modern life, coupled with our dense populations, have made it more likely that pathogens will make the jump from animal to human. Emerging disease hotspots often show the same trends in terms of high species diversity, large numbers of intensively farmed livestock, high human population densities and land use changes which increase contact with local wildlife. Intensive agriculture, wildlife provisioning and legal or illegal wildlife trade, which often occurs in unsanitary ‘wet markets’, are thought to be particularly problematic.

As stated by Prof. Drexler in his earlier talk, Dr. Epstein concluded that surveillance is critical, alongside appropriate community interventions in cases where spillover has been found. These may include, but are not limited to, reducing the commercial trade of wildlife, building barriers so that wild animals cannot come into contact with farmed livestock and their food, and protecting food sources (such as the date palm sap that is widely collected in Bangladesh and which is often contaminated with saliva and faeces from local flying foxes who have exploited this practice as a useful food source).

Towards the end of the day we were treated to an interactive session from Dr. Tigga Kingston (Texas Tech University, USA) who used the online whiteboard, Miro, to allow the audience to discuss and document what they felt were the biggest challenges for bat conservation. Personal observations were added in the form of virtual ‘sticky notes’ to each category and then the audience was asked to vote on which areas they felt confident in tackling, and which they felt less able to deal with. Persecution of bats, habitat loss, and restrictions on fieldwork/research due to Covid-19 were found to be areas that people generally felt were the most problematic and challenging to address. The talk ended with a brainstorming session to pose various solutions to these issues.

The second day featured a session on ecosystem services. This began with a keynote speech from Dr. Rudolf de Groot who spoke about the economic importance of bats. Much of his talk focused on the limitations of our current economic models (eg GDP) when it comes to conservation and the environment, as conservation is generally only ever considered as a cost, while ecosystem values and services are rarely factored into the equation.

In a paper published in Nature (1997), the global value of ecosystem services and natural capital was calculated to be US $33 trillion. To put this into perspective, global GDP at the time was US $27 dollars. A later paper, published in Science (2002) estimated that the cost of ecosystem loss was 2-5% GDP per year, and this was expected to increase to 7% by 2050. (Interestingly, and worryingly, the amount currently spent annually on protected areas is US $24 billion, just 40% of the amount that is spent each year on ice cream).

Speaking more specifically about bats, Dr. de Groot listed several of the services that are dependent on bats, including pest control, pollination of more than 300 food plants and 80 medicinal plants, as well as the development of several important vaccines following research into bat viruses.

His concluding remarks reminded us of the importance of raising awareness and spreading the message about the value of the natural world and the services it provides.

On the third and final day of the conference we heard a fascinating talk from Dr. Diogo Verissimo (University of Oxford, UK / Institute for Conservation Research, San Diego Zoo Global, USA) titled ‘Can Conservation Marketing Save Bats’. Many of the sessions from the final day had focused on the importance of social scientists and biologists working together to implement change and promote conservation practices. Dr. Verissimo’s talk took this a step further by discussing how effective marketing can contribute to conservation science.

The problem with bats – he initially stated – is that people don’t like them. In multiple surveys conducted around the world, bats rank low on the list in terms of popularity, and the current Covid-19 situation has done little to improve this state of affairs. He then went on to discuss how Batman is, conversely, one of the biggest media franchises of all time, and this indicates that the way in which a subject or species is marketed and packaged can have a huge impact on its public appeal.

Dr. Verissimo explained that ‘social marketing’ involves the use of marketing principles to influence the behaviour of individuals and communities for the general good. When it comes to conservation this means that we need to show individuals how conservation and ecosystem services have a value to them, whether that is a tangible benefit (such as pollination being vital for the food they enjoy), or intangible (such as pride in a local rare species or habitat).

He went on to suggest that emotions are much better at driving change and decisions than facts, and environmentalists must always remember that everyone in the world is not going to think in the same way as them, as people have different life experiences and therefore different priorities. It is incredibly important to understand the target audience of any marketing campaign and to appreciate that only a small percentage of this audience are likely to be influenced – however, these are the people that need to be focused on. Finding out who they are is a huge part of the process.

In his final remarks, Dr. Verissimo stressed the importance of including social science research when considering conservation and conservation marketing campaigns. Although working in such an inter-disciplinary manner can be a challenge in itself, he believes it is critical for the future of global conservation.

The talks and poster presentations that we saw over the three days of the meeting were lively and varied and it was great to hear from people from a variety of disciplines and backgrounds. I’m certain that everyone who attended would join me in congratulating the organisers of the meeting for an exceptionally well planned and executed meeting that brought together people from around the world to share their expertise and opinions on ‘The Human Perspective on Bats’.

6th International Berlin Bat Conference – Interview with Christian Voigt

The 6th International Berlin Bat Meeting is due to be held online from 22nd–24th March 2021 and will consist of a series of live lectures delivered via video link. To make it possible for people to attend from around the world, the lectures will also be available to watch on demand. At NHBS, we’ve always loved being involved with the Berlin Bat Meeting and hope that soon we can attend again in person!

In the build up to this exciting event, organiser Dr. Christian Voigt kindly took the time to answer some questions about this year’s meeting. Dr Voigt is Head of the Department of Evolutionary Ecology at Leibniz Institute for Zoo and Wildlife Research, Lecturer at the Freie Universität Berlin and Member of the Berlin-Brandenburg Centre for Stable Isotope Ecology.

The theme of this year’s International Berlin Bat Meeting is ‘The Human Perspective on Bats’. Can you tell us why you decided to choose this particular theme?

We decided on this topic because we became aware of the necessity to address bat conservation from a more holistic approach. Conservationists often have the saying ‘wildlife management is the management of humans’ and this is very much true. We need to better understand the emotions and attitudes of humans towards wildlife in general and bats in particular, in order to protect wildlife and bats respectively. Ultimately, this will make conservation more efficient. The Covid-19 pandemic told us that we were right because many aspects of bat conservation have turned more difficult when some people changed their attitude towards bats. It is important to remember that bat conservation does not only mean dealing with the protection of bat populations but also with their ecosystem function. In many cases, bats are very helpful for humans, e.g. by consuming large numbers of pest insects or because they pollinate flowers or disperse seeds. Becoming aware of these ecosystem services might change people’s minds about why they should care for bats. Lastly, zoonotic diseases such as Covid-19 emerge because the way we treat wildlife is wrong. Poaching, wet markets, our whole interaction with wildlife has to be reconsidered and we will be talking about this during the International Berlin Bat Meeting. The topic of the upcoming IBBM `’The human perspective on bats’ is more relevant and timely than ever.

What do you think are the key conservation challenges currently faced by bats?

The major challenge is now to re-establish a good reputation for bats. Bats are key players in ecosystems, they are important indicator species, and many species are rare or even threatened. We need to care for them.

How do you hope that this meeting will contribute to the work required to address these challenges?

Our hope is that we come up with ideas about how to approach bat conservation and human-bat interactions from a different angle. This conference will bring together people from various geographic backgrounds and from a variety of disciplines. It is this exchange of ideas and perspective that make the IBBM quite unique among bat conferences.

Meetings such as these provide an unrivalled chance for attendees to share ideas and network. Do you know of any key projects or collaborations that have arisen from previous International Berlin Bat Meetings?

The networking that happens during these meetings is huge. The very first IBBM on bat migration brought this topic to the attention of many people and lots of papers have been published since then. Specifically, our meeting on bat diseases, right when white-nose syndrome hit North American bats, stimulated a lot of excellent research on both continents. I remember that we sat together during the IBBM and discussed what should be done and what to expect.

Organising an online meeting must be very different in comparison to organising an ‘in person’ event. How have you found the process? And have you noticed that there are benefits to this format, as well as challenges?

Organizing an online meeting is overall not difficult, it was the postponing of the conference, not knowing when to reschedule it and not knowing how people would respond to an online instead of a presence conference that caused us sleepless nights. Now that we have already organized a few online events, the task seems doable. Overall, the benefits are that people from many more places on our globe can participate in this event without having to pay the travel costs. The challenge for these kinds of conferences is to maintain a format in which people feel encouraged to discuss and to interact. This can be better achieved when you meet in person, e.g. during coffee breaks. It is my hope that we have a very lively discussion and a very stimulating event.

For more information and to register for the 6th International Berlin Bat Meeting, visit the Leibniz Institute for Zoo and Wildlife Research website.

BCT Big Bat Skills Workshop 2021

On Friday 12th February the Bat Conservation Trust held their Big Bat Skills Event, which was run online via Zoom and breakout sessions. We were lucky enough to attend several sessions including the Introduction to Kaleidoscope for Bat Analysis run by Wildlife Acoustics – where we learned more about the many uses of Kaleidoscope software, Titley Scientific’s session on their product range and Anabat Insight software, Thermal Imaging by Dr Kayleigh Fawcett Williams and Emergency Bat Care for Ecologists by Maggie Brown. We cover a couple of these in a little more detail below.

We joined the session on thermal imaging run by Dr Kayleigh Fawcett Williams to learn more about how this equipment is being used in ecological consultancy. Most participants were new to thermal imagery, so Dr Fawcett Williams walked us through the basics. She explained that thermal imaging works by picking up thermoelectrics from the environment – infrared radiation, meaning that it is not at all invasive to the animals as the scopes emit no light (as opposed to night vision cameras that use infrared to light up the subjects).

Dr Fawcett Williams went through the benefits and applications of thermal imaging, and provided this helpful link to a copy of her Thermal Imaging: Bat Survey Guidelines published in association with the BCT.

The benefits of this survey method were explained, including: ability to use at all times of day and for long durations and cost effectiveness due to lack of man power needed. Thermal imaging can reduce the risk of false positives when it comes to identification of species and also provide a wider picture of landscape or infrastructure use by illustrating patterns of activity. She also highlighted that it is good for multidisciplinary work (e.g. for firms that work with engineers) as it has a range of applications that are not just ecology based.

Dr Fawcett Williams explained the difference between using thermal imaging as a survey ‘aid’ – assisting normal survey work, with live results, usually with lower end equipment; and using it for the entire survey ‘method’ – where higher accuracy is needed and results are analysed at a later date. When surveying for bats, Dr Fawcett Williams recommended using static detectors alongside thermal imaging but noted that the thermal imaging devices have a much longer detection range than static detectors and will pick up more than the static detectors. It is also vital that the time stamps of both devices are lined up so that they are able to be used in unison.

She also made sure to comment that thermal imaging devices cannot see through solid objects but pick up heat patterns which can often be things other than your target species (such as moisture). Thermal imaging is designed to be used for active animals and is therefore not recommended as a replacement for surveys such as internal roost surveys, especially as thermal imaging devices cannot pick up torpid bats.

It was then time to move onto the next session: Emergency Bat Care for Ecologists by Maggie Brown. This session focused on what to do if you came across an injured bat during an ecological survey.

She explained that bats are protected by law and that while only licensed individuals should be in contact with bats, first aid is considered emergency care and so this can be administered without a license. That being said, you will need to be able to justify any contact you have had with a bat so she strongly suggested that you keep records of the encounter.

Reasons that you would have to perform emergency care for bats were covered, such as when the individual is:

Exhausted or disoriented
Trapped and prevented from returning home
Too badly injured to fly and return home
Disturbed or have lost their roost
A flightless baby and has little or no fur; undeveloped wings but oversized thumbs and toes

Helpful equipment in an emergency bat care kit

She covered how to know when a bat needs food, how to feed them and how to recognise and deal with dehydration. Great emphasis was placed on the fact that you should always wear gloves for any contact with bats due to the potential risk of them having a strain of rabies (EBLV), and that for this reason some vets may refuse to treat them. It is very important to recognise how much care you would be able to provide yourself and when it is best to pass the care onto a long term bat carer or enlist the help of a vet.

If you think that you may end up in a situation where you need to administer emergency bat first aid, I would highly recommend attending one of Maggie Brown’s very informative sessions and, when possible, formal training.

The BCT website is also a useful resource, offering advice on emergency bat care and providing information about the opportunities available for those looking to volunteer.

Overall, the day was very interesting and educational, and it was nice to see such a range of skill sets attending the workshop as well as the enthusiasm shared by all.

You can stay up to date with upcoming BCT events by signing up to the BCT mailing list.

NHBS In the Field – Echo Meter Touch 2

First released in 2017, the Echo Meter Touch 2 (EMT2) and Echo Meter Touch 2 Pro (EMT2 Pro) from Wildlife Acoustics are highly popular bat detectors for naturalists and professionals alike. By plugging the units directly into your phone or tablet, your device is transformed into a fully functional, full spectrum bat detector. The free Echo Meter app (available on the App Store and Google Play Store) allows the user to watch live, real-time sonograms as bats pass above.

The EMT2 Pro can be purchased as either an iOS model (with a lightning connector) or an Android model (with a USB-C connector), but the EMT2 is now only available as an Android model. We highly recommended checking the list of compatible devices on the Wildlife Acoustics website before purchasing your EMT2 (see compatibility of phones and tablets here for Android). This list is not exhaustive and is continually updated as further models are tested.

When using in conjunction with an Android device with a USB-C connector, an adapter will be required. As of 2021 these are now included for free with all Android Echo Meters, an addition we are sure will be greatly appreciated by customers going forward.

The EMT2 Pro is very similar to its counterpart, however additional features and a higher quality microphone make this option more suitable for professional ecological surveys and acoustic analysis. Adjustable gain (Low -12dB, Medium or High +12dB) is one particularly helpful addition. For a full break down of the differences between the EMT2 and the EMT2 Pro please see Wildlife Acoustics’ comparison page.

We plan to further test and compare the EMT2 and EMT2 Pro for a future post. On this occasion we only tested the EMT2 – but the set up and use is fundamentally similar for both models.

How we tested

During August 2020 we took several EMT2 units to a nearby woodland to survey for the presence of bats. The Android units were used in conjunction with a Samsung Galaxy Tab S3 (requiring the micro USB to USB-C adapter) and the iOS units used with an iPhone SE 2020.

The EMT2 is incredibly lightweight and small, weighing just 20g and measuring 48 x 35mm. Supplied in a small pouch, the detector is perfectly pocket-sized. For peace of mind, we connected a keychain to the pouch to keep it safely clipped to the inside of our bag.

Set-up was incredibly easy; we simply downloaded the free application, plugged in the device and immediately began recording. It is worth noting that, when plugging the EMT2 into the phones without an adapter, the phone cases had to be removed in order to allow proper connection.

We made sure that the Trigger Minimum Frequency was set to 12kHz, the level recommended by Wildlife Acoustics in order to stop noise recordings while not missing any species of bat. On the ‘Auto ID Selection’ tab, we chose the correct region and country allowing the impressive auto-ID feature for UK bat species to be enabled (see video below on how to change these settings).

The EMT2 then automatically recorded any bat activity detected above 12kHz and applied a suggested species identification based on the waveform and frequency. The app offers several ways to share these recordings, but we chose to directly plug our phones/tablets into a computer to transfer the files directly.

What we found

The Echo Meter is incredibly intuitive and easy to use, so certainly suitable for beginners and professionals alike. Any questions or issues can easily be resolved via the User Manual, found under the Information tab on the app and offered in English, French and German. Personally, we preferred this digital option rather than having to flick through a paper copy during a dark evening survey. However, copies of the user manuals can be found here, for those who would prefer to print a hard copy.

The on-screen live sonograms were particularly impressive and allow surveyors to get an idea of the potential species present while still in the field. While waiting for the bats to emerge, we enjoyed watching the calls of birds and crickets (see our blog post here on monitoring Orthoptera using bat detectors) – an unexpected advantage of the EMT2. It is certainly understandable why the EMT2 is so often used for community engagement at bat walks and BioBlitzs around the country.

We found that, for the species common in our area, such as Common Pipistrelle (Pipistrellus pipistrellus), Soprano Pipistrelle (Pipistrellus pygmaeus) and the Noctule (Nyctalus noctule), the auto-ID feature appeared mostly accurate. Although, on one occasion before dusk we found that a bird call triggered a Common Pipistrelle identification. It is important to note that no Auto-ID feature can be 100% accurate, and Wildlife Acoustics make it clear that users should always manually verify the identification.

The automatic triggered recording worked very smoothly and did not appear to miss any bat activity. Despite this, it was reassuring to know if we noticed something we wanted to record, we also had the option to manually trigger recording – another feature that would be useful if wanting to listen to non-bat species. Each recording was GPS tagged, a neat feature that tracked our transect throughout the evening. When sorting through recordings, the option to sort by species was helpful to move noise and ‘No ID’ audio clips.

The only limitation we found with the EMT2 is how quickly our batteries drained. This is of course not a fault with the EMT2 itself and is to be expected with continual recording, but it is worth considering your phone or tablet’s battery life may impact your use of this detector.

Overall, the Echo Meter Touch 2 is a fantastic detector that is very affordably priced for the number of features it offers. The free app is continuously updated, and newly developed species classifiers added.

Common Pipistrelle (left) and Soprano Pipistrelle (right) recorded and identified on the Echo Meter app.

The Echo Meter Touch 2 and Echo Meter Touch 2 Pro are available from the NHBS website.

Visit nhbs.com to view our full range of bat detectors. If you have any questions about our range or would like some advice on the right product for you, then please contact us via email at customer.services@nhbs.com or phone on 01803 865913.

Winter Hibernation

What is hibernation?

During the winter months, cold temperatures and a lack of food can make survival challenging for many species. Some animals, particularly birds, solve this problem by migrating to a warmer location where food is more plentiful. Other animals utilise a different solution and enter a period of torpor or hibernation as a way of conserving energy throughout this time.

During hibernation, the animal will slow their heart rate and breathing while at the same time lowering their metabolism and body temperature, all of which vastly reduce the amount of energy they require. Throughout the hibernation period, the animal may become active again briefly, either for a bathroom break, to eat some food, or if the temperature becomes too low for them to survive without moving. As preparation for a period of hibernation, as much food as possible will be consumed and a suitable refuge or hibernacula found (or built).

Which animals hibernate in the UK?

Dormice, along with bats and hedgehogs, spend the winter months in hibernation. Image by Bruce Detorres via Flickr.

Mammals

Although many small mammals, including mice, shrews, badgers and rabbits, enter short periods of torpor throughout the winter, the only mammals in the UK that truly hibernate are bats, dormice and hedgehogs. Bats utilise hollow trees, roof spaces, caves and bat boxes and will usually spend the entire winter, from November to April, in hibernation. Dormice choose the seemingly riskier solution of making a nest using natural items such as logs and leaves on the floor of forests and woodland. Hedgehogs build hibernacula using dead leaves, twigs, log stacks and compost heaps and, although evidence shows that they rouse several times during their hibernation, they rarely leave these nests. The only exception to this is when the temperature drops too low – at this point they may depart their existing nest and build a completely new one with better insulation! In general, hedgehogs hibernate from November to April, but depending on the temperature and weather, this can vary from year to year.

Reptiles and Amphibians

All reptiles in the UK hibernate. Typically this will begin in October in response to reduced daytime temperature and shorter day length, but it can vary depending on the year and species. In general reptiles will use dry and sheltered spots, often utilising tree roots, abandoned animal burrows or compost heaps.

All species of amphibian in the UK also hibernate, although not all individuals will do so on any given year. In mild winters newts may simply enter a state of low activity rather than complete hibernation. Most amphibians will choose a quiet location in the soil, a compost heap or rockery, or even a garden shed to spend their hibernation. A small number of frogs, however, will hibernate at the bottom of a pond.

Insects

Bumblebee colonies die off in the autumn with only the new queens surviving. To make it through the winter, these queens burrow into the soil where they are protected from the cold and weather for up to nine months! Honey bees use a different strategy and do not hibernate as such – instead they survive as a reduced-size colony which huddles together with the queen at the centre. The bees rotate their positions so that each takes its turn on the outside where the temperature is lowest.

Most butterflies spend the winter in larval form. Several species however, including Brimstone, Peacock and Comma will hibernate as adults, using either vegetation such as bramble and ivy, or outdoor structures such as garden sheds and barns.

Ladybirds survive the cold winter by hibernating in rotting logs, under leaf litter or even inside houses. They like to hibernate in colonies, often forming groups containing thousands of individuals.

Ladybirds emerging from hibernation. Image by Dr. Mary Gillham Archive Project via Flickr.

Climate change and hibernation

Most animals that hibernate rely on a combination of cues such as day length and temperature to know when it is the right time. As climate change continues to affect local and global temperatures and weather patterns, many animals are hibernating later in the year and becoming active again earlier in the spring, as temperatures during the winter are now often much warmer. Hibernating for a shorter period can put pressure on food availability and can cause a mismatch in the timing when animals require a resource and when that resource is available. For example, bees emerging from hibernation require a ready supply of nectar. If they emerge earlier than usual however, before flowering season, this food source may not be available to them.

Always make sure to check your bonfire for hibernating animals! Image by Ian Carroll via Flickr.

How can I help hibernating animals?

• Leaving some areas of your garden that are untidy and overgrown will provide plenty of space for animals to hibernate over the winter. Piles of logs, long grass and compost heaps all provide safe places for animals such as snakes, hedgehogs and other small mammals.

• If you’re celebrating bonfire night, don’t forget to check the bonfire for hibernating animals before you light it – particularly if you have built the structure several days or weeks before the big night.

• Providing artificial hibernacula in your garden, such as a bat box, hedgehog house, or insect box, will help to provide suitable hibernation spots for these species.

• If you find a butterfly that has chosen to hibernate inside your house, it’s best to gently relocate it to an unheated building outside, such as a shed or garage. (Central heating is extremely damaging to a hibernating butterfly and will desiccate their delicate wings and bodies).

• Don’t forget those animals that don’t hibernate over winter. Birds in particular will benefit from a variety of foods such as peanuts, mealworms, fat balls and seed.

The Acoustic Identification of Small Mammals

As static bat detectors have become more widely used, there are now many thousands of hours’ worth of nocturnal recordings captured each year from a vast spread of locations. This level of coverage has not only improved our ability to monitor bat populations, but also offers the potential to gather information on other animals that communicate at the same ultrasonic frequencies as bats. The calls of bush-crickets, for example, are commonly picked up as ‘by-catch’ during bat surveys, which has allowed the development of software that automatically recognises any cricket calls in a recording and assigns them to individual species.

In the December issue of British Wildlife, Stuart Newson, Neil Middleton and Huma Pearce explore the previously untapped potential of acoustics for the survey of small terrestrial mammals – rats, mice, voles, dormice and shrews. Small mammals use their calls for a variety of purposes, including courtship, aggressive encounters with rivals and communication between parents and their offspring. To the human ear, the high-pitched squeaks of different species sound much alike, but closer examination reveals them to be highly complex, extending beyond the range of our hearing into the ultrasonic and showing great variation in structure.

Mammal terrariums used for holding individuals overnight in the recording ‘studio’.

But is it possible to distinguish the calls of different species? To answer this question, the authors began the time-consuming task of building a call library by taking recordings of all Britain’s native (and some non-native) small mammals. Call-analysis software was then used to examine the recordings and look for consistent differences between species, with some fascinating results – the calls of shrews, for example, can be readily separated from those of rodents by their warbling/twittering quality, while the house mouse typically calls at a higher frequency than any other species. Remarkably, it appears overall that the vocalisations of most species have their own diagnostic features, and that, with care, it should be possible to identify a high proportion of calls to species level.

Recorded calls of (a) Brown & (b) Black Rats

Small mammals are unobtrusive and hard to observe, which means that even the more familiar species, such as the Brown Rat, are severely under-recorded. The ability to detect and identify small mammals by their calls therefore offers great potential to help fill gaps in our knowledge of the distribution and abundance of British species. Analysis of calls collected by static detectors – whether specifically set to target small mammals or deployed as part of a bat survey – could in future offer a rich source of data and help to complement traditional methods, such as the use of Longworth traps or footprint tunnels.

To read about the key identification features of small-mammal calls, see the December issue of British Wildlife (more information can be found on the British Wildlife website) and to accompany this article, audio clips of the species discussed are available to download here. This work will contribute to the BTO Acoustic Pipeline, which allows the upload of sound recordings and automatically detects and identifies any calls of bats, bush-crickets and small mammals. For more information about the project, see the BTO Acoustic Pipeline webpage and read comments from the authors here.

Bat detectors for small mammal survey:

Passive bat detectors are designed to be left in the field for unattended monitoring and are the ideal choice for ecologists and researchers wishing to monitor local bat populations. For similar reasons, they are also a good choice for recording small mammals as they record all frequencies continuously and retain complex details of the call structure, allowing the sounds to be analysed later using bioacoustics software. Detectors such as the Song Meter Mini, Anabat Swift and Elekon Batlogger A+ all features excellent weatherproofing, long battery life and the ability to programme recording schedules.

Song Meter Mini
#248177

Anabat Swift
#236256

Elekon Batlogger A+
#228313

Tag: Mammals