Author interview with Phil Sterling and Mark Parsons: Field Guide to the Micro-moths of Great Britain and Ireland

Part of the popular Bloomsbury Wildlife Guides series, the first edition of the Field Guide to the Micro-moths of Great Britain and Ireland is credited with helping to demystify the formerly obscure and specialist world of micro-moths. Among a number of pioneering features, the book boasted artwork by acclaimed illustrator Richard Lewington showing the moths in their natural resting positions, rather than as pinned specimens, capturing the essence of each species and presenting them as they would appear in life when encountered in the field or settled within a moth trap. Coupled with accessible species accounts and the latest distribution maps, the guide helped to showcase the beauty and diversity of these miniature lepidopterans and provide a gentle introduction to their identification and habits for the general naturalist.

Eleven years on, the team behind the original guide have produced an extensively revised second edition, due to be published in December. Here the authors, Phil Sterling and Mark Parsons, kindly took the time to answer some of our questions about what we can expect from the new guide, and about micro-moth recording more generally.

Authors Mark Parsons (left) and Phil Sterling (right)

To begin with, could you give us a brief overview of what’s changed in the second edition?

There are three stand-out changes for recorders browsing this second edition. Firstly, we have included many more species, nearly 300 of them; the field guide now covers over 80% of native, naturalised or immigrant species recorded in Great Britain and Ireland. That’s 1,286 from a total of 1,576 species, and the book features over 1,000 of Richard Lewington’s illustrations.

This time we have included a full set of common (or vernacular) names for the micros which appear alongside the scientific names. We reviewed existing common names being used, made changes where we felt these were appropriate and helpful, and have done this for all 1,576 species.

The order in which the species are presented is now in line with the Agassiz, Beavan & Heckford (ABH) Checklist of the Lepidoptera of the British Isles. The ABH checklist was published in 2013, a year after our first edition, and it set out a radically different order based on our current understanding of the taxonomic relationship between species, genera and families. This should make it much easier for recorders to relate the order in the field guide to established recording systems and websites.

Box-tree Moth by Phil Sterling

You mention that the species coverage has been greatly expanded since the first edition. Where have these ‘new’ species come from?

There are a variety of reasons why we include more species. Most obvious are those we see today but did not 11 or more years ago. In 2007 when we started writing the first edition, Box-tree Moth hadn’t been recorded in Britain, yet it is now an abundant species across much of southern England and set to spread fast. Our warming climate is also leading to rapid increases in micro-moth species establishing and spreading, and we have included several scarcer immigrant species which do seem to becoming more regularly recorded.

We will never be up-to-date though. No sooner had the second edition gone to print than Echium Stilt Dialectica scalariella made a spectacular appearance in Britain in autumn 2023. It now appears to be resident at various sites from Kent to Devon, and possibly Suffolk, and has been found in huge numbers as a leaf-miner on Viper’s-bugloss, disfiguring the leaves. This species is listed in the field guide as British but not covered in detail.

We have taken a more systematic approach to inclusion of those that can be identified to species from their early stages, in particular leaf-miners in the Nepticulidae and Gracillariidae, and cases of the Coleophoridae. We have chosen a wide selection of these, illustrated by good quality photographs, enabling identification to species based on the early stage.

We have responded to helpful criticism that we should have been more comprehensive in our coverage of some of the more difficult families, including Gelechiidae and Depressariidae. There is better knowledge ‘out there’ today of how to separate species in the field, and we have been able include this information for some of the more challenging species within these groups.

There will be recorders who would have wished we included yet more species, maybe even all of them? But we have kept faithful to the objective of this being a field guide, for recorders to take it whenever they are out, by day and night. Most of the remaining 20% of micros require detailed examination under a microscope, extended time to rear the species from larva to adult to confirm identity, or are very rarely encountered species.

The bottom line is that we requested to Bloomsbury and they allowed us to write a bigger book than the first edition. We have packed it to our limit with more species and more information.

Mine of the Echium Stilt on Viper’s Bugloss by Mark Parsons.

For me (and I suspect many other people), the first edition of this guide was the catalyst to start paying more attention to micro-moths, having previously written them off as ‘too difficult’. How do you feel interest in micro-moths has changed in the 11 years since the original was published?

The first edition certainly achieved its aim of bringing micro-moths within comfortable reach of many recorders who had perhaps previously not considered them. Many species are actually straightforward to identify, but we think recorders were put off by the need to acquire several expensive texts to gain comprehensive coverage.

Moth recording generally continues to grow and it has wide public appeal. The National Moth Recording Scheme (NMRS), run by Butterfly Conservation, collates moth records across the four countries in Britain and Ireland and does not separate macro- and micro-moth species. We feel the distinction is fading, with recorders deciding which micro-moth families they’ll tackle in the coming year, rather than considering the prospect too daunting.

Leaf-mine of the Sorrel Dot Enteucha acetosae on Sheep’s Sorrel by Ben Smart.

Has that growth in interest in micro-moths helped you in your revisions to this guide, e.g. by helping to fill gaps in distribution maps and so on?

The first edition was primarily aimed at moth trappers, and we included lots of photographs of leaf-mines and larval cases to add interest. In the second edition we have deliberately chosen photographs of the early stages where identification to species level is possible based on a photograph and careful observation. We want to extend recorders’ interests beyond their moth traps to include searching for leaf-mines, cases and other signs in the field. Daytime pursuit of micro-moths can happen 365 days of the year, and there are plenty of species detectable in the middle of winter. The second edition benefits especially in this respect from photographs by Ben Smart, who has already published two small volumes on Micro-moth Field Tips, both giving month-by-month hints on how to find the early stages. Having said that, the second edition remains very much a book for moth trappers, and we have added illustrations of many more adult moths from a range of families.

Black-barred Fungus Moth Nemapogon clematella by Phil Sterling.

Could you tell us a little bit about the motivation and process behind your efforts to create the standardised list of common names in this guide?

Common names of micro-moths have never been adopted widely by recorders in Britain and Ireland. There is a long history to them, with a list first appearing in the early 17th century, and the most recent compilation was collated by Jim Wheeler in 2017. Despite the efforts, it is a ‘Marmite’ subject, with common names being used by some recorders yet remaining deeply unpopular with others. Much of the angst seems to centre on the inappropriateness of some names. All members of the Tineidae have been called ‘clothes moths’ yet this wonderfully diverse group contains only a very few species that will eat clothes, the majority are in fact detritivores and herbivores, with a range of specialists on fungi. Labelling them all as if they are clothes-munchers is just plain wrong at best, and gives moths a bad name at worst. Each fungal specialist is, not surprisingly, called a type of ‘fungus moth’, a simple revision based on its life history. There are other names that today appear to be meaningless, such as ‘tubic’, which gives recorders little to grasp when trying to remember them.

The introduction of a revised set of common names, in tandem with the increasing interest and our continued desire to promote micro-moth recording to all, seemed timely with the advent of the second edition. Very many common names remain as they are in the Wheeler list, or are slightly modified, and we have tried to make revisions that add relevance to the species, such as what it looks like, or where and how it lives. We hope that the names will make micros even more accessible by removing the perception that they somehow require more specialist knowledge to tackle.

Most recorders now use social media to communicate their finds, and it is undoubtedly easier to write an English common name than the scientific equivalent, and we have tried to keep the names as short as possible with this in mind. In summary, we hope that the revised list will be adopted in time and will encourage an inclusivity for new recorders put off by scientific names, and we trust we are putting micro-moths alongside almost all groups of British wildlife that now have common names.

Phil Sterling searching for larvae on Alderney by Peter Costen.

For any enthusiasts who have not yet looked beyond the more familiar macro-moths, what can you say about the rewards of taking the plunge into the world of micros?

Macro-moth recorders are delighted when they find something of great interest in their garden moth trap, it’s exciting, and it can happen to new and seasoned recorders. Imagine increasing your chances of this happening threefold! There are roughly twice as many micro-moth species as macros, plus their distribution is generally less well known, so the chances of finding ‘goodies’ is much enhanced. The advent of pocket-sized cameras and mobile phones with decent macro-photographic capability means that it is easier to share photos of micro-moths with others than it has ever been. Add to that the opportunity to record so many species from their early stages, and at any time of year, what are people waiting for?

Records of micro-moths are collated by the NMRS. By encouraging recording the amount of data collected will increase, along with our understanding of distributions and phenology. It won’t be long, we hope, until we can see national distribution maps for micros just like the macros.

Finally, are there any other projects you’re working on that you’d like to tell us about?

For us there is the continued quest to resolve undescribed life histories of micro-moths. Even some species seen regularly as an adult are not known as a larva, such as Dingy Knot-horn Hypochalcia ahenella. It probably feeds on herbs within its favoured habitats, sparsely vegetated stony or sandy ground. For what must be quite a large larva it is certainly secretive and has eluded us to date.

One mystery partly revealed in 2023 was the finding of a larva by Phil of Black-spotted Nest Moth Tenaga nigripunctella. The life history of this very rare tineid moth was completely unknown anywhere in the world and it was assumed that the larva might feed underground in rats’ nests. The adults have been appearing more regularly in west Dorset in the last few years, and a few were observed in a hole in a stone wall at Abbotsbury in 2023. In the wall was a dead Garden Snail Cornu aspersum, and guess what; deep within the shell a fully-fed larva of the moth that appeared to have been eating the blackened dead flesh of the snail. As far as we are aware this is the first example of a moth in western Europe found to be eating dead snails. There is so much to learn about the intriguing life histories of our more obscure micro-moths!


Field Guide to the Micro-moths of Great Britain and Ireland (Second Edition) is due to be published by Bloomsbury in December 2023 and is available from nhbs.com.

Author Q&A with Kayleigh Fawcett Williams: Thermal Imaging for Wildlife Applications

Thermal Imaging for Wildlife Applications offers readers an invaluable and practical guide to this exciting technology. Covering a wealth of basics, including the history of thermal imaging and its advantages and challenges, the book also provides readers with all the information they need to begin choosing and using the right equipment. A chapter on wildlife applications covers all of the main animal groups for which the technology is of use, and a final chapter discusses the future possibilities of thermal imaging.

Kayleigh Fawcett Williams is a Wildlife Technology Trainer and Consultant and has been using technology for wildlife applications for the past sixteen years. As the founder of Wildlifetek and KFW Scientific & Creative she helps wildlife students, professionals and enthusiasts use technology to improve their wildlife work via her online training and support services. Kayleigh is also the author of the Thermal Imaging Bat Survey Guidelines which were published in 2019 in association with the Bat Conservation Trust (BCT).


During your PhD, you spent some time training to be a thermographer. What did this training involve, and how valuable do you consider this type of ‘formal’ training to be for anyone wanting to use thermal imaging equipment for their work or studies?

My thermography journey really began when I took my Level 1 Thermography Certification. This was an in-depth technical training with the Infrared Training Centre (ITC) at FLIR’s UK Headquarters in West Malling. It was a fantastic grounding in thermal science and kick-started my use of this technology. I always recommend this training to students and researchers who need to know how to carry out temperature measurement. This is usually only for very specialist research applications where the body temperature of the animal that they are working with is needed.

However, it’s definitely not for everyone. In fact, very few wildlife applications require temperature measurement, but all of them require an understanding of how the technology works, its limitations and, of course, its benefits. That’s why I have since developed wildlife-specific training for those that want to use this technology effectively but don’t need temperature measurements.

Thermal imaging equipment has been around in one form or another since the 1960s/70s. Why do you think it has taken so long for it to become more widely adopted?

It’s a long story, which I cover in much more detail in the book, but I think there are two key elements that have affected our adoption of this technology for wildlife.

Firstly, a key factor is the nature of the equipment itself. Early thermal imaging devices were expensive and cumbersome, making them largely inaccessible and impractical for most wildlife professionals. Over the decades, we have seen huge improvements in both the affordability and practicality of models available on the market. This has accelerated in recent years, where we’ve seen a massive shift towards the use of thermal imaging by both professional wildlife ecologists and amateur recorders alike.

Secondly, another major influence is the expertise of those using the equipment. Without an appropriate understanding of the technology, many have failed in their attempts to use it effectively. Unfortunately, in some cases this has led to misuse and the spread of misinformation about the technology. This has undoubtedly slowed our adoption of this technology for wildlife purposes.

Among the 300+ documents I reviewed as part of the research for the book, I noticed time and time again that these factors, equipment and expertise, determine the success or failure of thermal imaging for a wide range of wildlife species.

What do you consider to be the main challenges in working with this type of equipment?

Again, it is usually those same two factors we just discussed: equipment and expertise.

The number one question I am asked by ecologists, researchers and amateur recorders is: “What thermal imaging equipment should I buy?”. With an ever increasing list of thermal imaging devices available for us to buy, we can experience a paradox of choice where we can become confused by the array of different options on offer. So choosing the appropriate equipment for a specific wildlife application can be challenging, yet it is absolutely vital to get this bit right.

Once we have chosen our kit, the next challenge is being able to use it effectively. This requires an appropriate level of knowledge and experience, but acquiring this kind of expertise can be difficult, as I found out when I first began my work in this area thirteen years ago. Back then there were very few training opportunities and hardly anyone was using the technique outside of academia. Thankfully, things have changed a lot since then and wildlife-specific training is now available, making it much less of a challenge to access the knowledge and develop the skills that are needed.

The recently published 4th edition of Bat Surveys for Professional Ecologists includes, for the first time, new content on night-vision aids. How much of an impact do you think these recommendations will have on routine bat surveys and their results?

I think the widespread use of night-vision aids for bat surveys will be transformative for the ecology sector. Personally, I have been using thermal imaging technology for this kind of survey for many years so I am well aware of what we can achieve using night-vision aids compared to traditional methods. As a trainer, I am lucky that I also get to see lots of my students experience this for themselves. Many ecologists have told me what a game-changer it has been for them and what a difference it can make to their survey results.

So what have they been missing? Well, in the past, without using night-vision aids, surveyors often battled with the painful but common uncertainty that can lead to writing the words “possible bat emergence” on a survey form. The knock-on effects of these three words can spiral out of control, leading to a raft of unnecessary effort and costs associated with a bat that may or may not have emerged from a tree, building or other man-made structure. On the other hand, we can also easily miss bats using traditional methods. This can of course be costly financially but, more importantly, can lead to harm to the bats themselves.

So it is undoubtedly going to have some massive benefits, but it is also important to consider that, to achieve them, many ecologists out there are now having to get to grips with some new technologies. Some have found this easy and have embraced this change with enthusiasm, while others have a steep learning curve to contend with. Either way, I think it is going to be worth it.

When considering the use of thermal imaging equipment, a lot of attention is given to choosing the right product and designing a suitable survey protocol. However, do you think that the post-processing stage is equally important? And are there widely available software packages that can help with data processing and analysis?

Post-processing and analysis can be just as important, depending on the target species. When used for bat surveys, for example, post-processing and analysis using specialist software packages can make a big difference to the level of accuracy we can achieve using thermal imaging technology. To get those levels of accuracy, however, requires another level of cost in terms of effort, time and investment in software packages. Some software packages for these tasks can be quite expensive, but there are open source options as well. Thankfully, advances in automation procedures are also paving the way to streamlining this process in the future.

Finally, what’s keeping you busy this winter? Do you have plans to write further books?

I do have plans for another book, but right now I am taking a break from writing to focus on something a little bit different. I am currently filming some exciting footage for an upcoming video series called “Wildlife Detectives” on my new YouTube Channel. As part of this I will be using some really cool technologies, including thermal imaging, to find some fascinating wildlife species out in the field. Keep an eye out for it in the New Year!


Thermal Imaging for Wildlife Applications by Kayleigh Fawcett Williams was published in October 2023 by Pelagic Publishing and is available from nhbs.com.

Book review: The Mind of a Bee

***** Fascinating and information dense
 Leon Vlieger, NHBS Catalogue Editor

It is tough being a social insect. When people are not trying to exterminate you, they might marvel at the collectives you form, but does anybody think much of you, the individual? Leave it to Lars Chittka, a professor in sensory and behavioural ecology, to change your views. The Mind of a Bee is a richly illustrated, information-dense book that explores a large body of scientific research, both old and new.

Chittka is very focused in his approach and The Mind of a Bee effectively summarises a large number of experimental studies in narrative form, with very few diversions. He cleverly avoids overheating your brain by having chapters flow logically into each other, but especially by dividing each chapter into short, headed sections. Each of these takes a particular question and discusses a few relevant studies in anywhere from one-half to three pages. Some of these are his own work but he ranges far and wide and includes both classic and recent research. The book is furthermore illustrated with numerous diagrams and photos that helpfully clarify experimental protocols and results. Honey bees are unsurprisingly the most intensively studied but Chittka discusses informative studies across a range of bee species and sometimes other insects as well. The book roughly covers three biological disciplines: sensory and neurobiology, ethology, and psychology.

Justifiably, the book opens with sensory biology. Before we understand what is in the mind of any organism, Chittka argues, we first need to understand the gateways, the sense organs, through which information from the outside world is filtered. These are shaped by both evolutionary history and daily life (i.e. what information matters on a day-to-day basis and what can be safely ignored). Chapter 2 deals with the historical research that showed that bees do have colour vision and furthermore can perceive ultraviolet (UV) light. Chapter 3 bundles together research on numerous other senses, including ones familiar (smell, taste, and hearing) and unfamiliar to us (perception of polarised light, Earth’s magnetic field, and electric fields). The antennae of bees, in particular, are marvels; Chittka likens them to a biological Swiss army knife, packing numerous different sense organs into two small appendages. Tightly connected to sensory biology is how this incoming information is processed in the brain, though Chittka postpones discussing neurobiology to chapter 9. He describes the discovery and function of different brain areas and highlights the work of Frederick Kenyon who would inspire the better-remembered Santiago Ramón y Cajal. Thanks to them, we now understand that brains consist of numerous specialised nerve cells. Though the bee brain is small, Chittka argues that size is a poor predictor of cognitive skills; it is the wiring of neurons that matters. Rather than be surprised that small-brained insects such as bees can do so many clever things, Chittka instead tickles the reader with the opposite question: “Why does any animal need as large a brain as a bee’s?” (p. 153).

What clever things do bees do, you ask? That is the subject of the preceding five chapters where Chittka surveys a large body of behavioural research. Honey bees are famous for their waggle dance by which they communicate the location of flowers but also, this was news to me, the location of potential nest sites when the swarm relocates. But Chittka discusses more, much more: how bees navigate space using landmarks, show a rudimentary form of counting, solve the travelling salesman problem, learn to extract nectar from complex flowers, learn when to exploit certain flowers (and when to ignore them), and learn new tricks by observing other bees. But what about instinct, something most behaviours were traditionally ascribed to? He has some insightful comments on this: “even the most elemental behavior routines need to be refined by learning: instinct provides little more than a rough template” (p. 50). What really made me fall off my chair is that bees have long been outsmarting researchers in choice experiments. Many behavioural experiments take the form of choice tests, where bees need to pick between two locations or objects that differ in e.g. colour or shape with one option containing a sugary solution as a reward. Bumblebees would simply be lazy and check out both options in random order. Until, that is, protocols were modified by adding a bitter-tasting solution to the wrong choice as a penalty.

The final two chapters explore bee psychology. One chapter shows how, in a hive full of bees, the members are not anonymous and interchangeable. Rather, they show individual differences in e.g. their preferred order in which to visit flowers during foraging or how fast they learn to solve problems. The final chapter makes the case that bees have a form of consciousness, though Chittka clarifies he is not arguing it is as rich and detailed as that of humans. That said, they show a slew of behaviours that scientists will label as evidence for consciousness when exhibited by bigger-brained vertebrates. Chittka is happy to play devil’s advocate: sure, theoretically, all the behaviours described in this book could be replicated by an unconscious algorithm. However, the required list of specific instructions is growing long and, increasingly, the more likely answer seems to be that bees possess “a consciousness-based general intelligence system” (p. 208).

As mentioned above, this book is focused. If you enjoy reading about the facts and the study system with minimal (autobiographical) diversions, Chittka has got you covered. The only digression he allows himself is to include biographical details of older generations of scientists. This includes inspiring tales such as Karl von Frisch who described the honey bee waggle dance and later barely escaped being dismissed from his post by the Nazis. And look out for repeat appearances of Charles Turner, a now largely forgotten African American scientist who published pioneering work despite having been denied a professorship based on his ethnicity. But there are also tragic stories such as Kenyon’s, who snapped under pressure of not securing a permanent job and was incarcerated in a lunatic asylum where he died more than 40 years later, alone and forgotten. Chittka includes occasional quotations from historical literature to show that “many seemingly contemporary ideas about the minds of bees had already been expressed, in some form, over a century ago” (p. 15).

The Mind of a Bee makes for fascinating reading, convincingly showing that bees are anything but little automatons. The tight structure and numerous illustrations make it accessible, though be prepared for an information-dense book.

NHBS staff picks 2023

Every year at NHBS we see a huge range of books and equipment travel through our offices and warehouse, via desks and bookshelves, finally leaving us in packages on their way to our valued customers. Invariably, we end up purchasing a number of these for ourselves, and others become gifts for our friends and families. This year, for our staff picks roundup, we have chosen the books and equipment items that we’re hoping to gift to our loved ones this Christmas.


Blue Machine: How the Ocean Shapes Our World 

An engrossing odyssey into oceanography that reveals a fascinating planetary engine. Equal parts physical oceanography, marine biology, and science history, topped off with human-interest stories, Czerski has written a captivating book that oozes lyricism in places.
Leon Vlieger, Catalogue Editor

 

NHBS Kent Bat Box

New for 2023, the NHBS Kent Bat box is based on the proven and popular design from the Kent Bat Group. Made from untreated rough-sawn Douglas Fir, the box is self-cleaning, easy to install and reasonably priced, making it an ideal gift for the bat enthusiast in your life.
Johnny Mitchell, Senior Wildlife Equipment Specialist

 

The Book of Wilding: A Practical Guide to Rewilding Big and Small 

An attractive, practical and inspiring guide that not only illuminates the greater need for wilding in the larger landscape, but also some really thoughtful ways people can engage on smaller scales. It’s hopeful too, which makes a good gift I always think!
Oli Haines, Graphic Designer

 

Echo Meter Touch 2

A fantastic gift for someone with an interest in bats. To set it up, simply plug it into your phone and start recording. It converts the ultrasonic sounds from the bats into audible noises and auto-identifies the species you are listening to.
Samuel Brook, Technical Advisor

 

Antarctica: A Birds-eye View

A beautiful coffee table book which I would like for myself or my photographer friends. A book that gives you an insight into a threatened world from a view you wouldn’t normally see. Both beautiful and barren, the images create a feeling of being there with the nature and environment that is threatened and disappearing fast.
Simon Palmer, Technical Advisor

Dinosaur Monopoly

I bought this for my son as a present last year as he is obsessed with Monopoly and dinosaurs. It was such a hit, my youngest son asked for it this year. It is a great alternative to traditional Monopoly and we loved the dinosaur pieces .
Mark Fisher, Product and Purchasing Manager

 

The Observant Walker: Wild Food, Nature and Hidden Treasures on the Pathways of Britain

It is always a pleasure to gift someone a book that you have previously delighted in reading yourself. The Observant Walker for me is one such book. Written in John Wright’s wonderfully conversational style, the book is both informative and witty; the perfect choice for anyone who loves nature and discovering its edible bounties.
Luanne Wilkes, Senior Editor

 

 

Image of the Digi-Scope Smart Phone Adapter being used with a binocular scope attached taking a photo of a black and white bird in grass.Digi-Scope Smartphone Adapter

Really useful for anyone who wants to try taking pictures while they’re out exploring nature with their binoculars and want to quickly be able to take pictures of what they’re seeing through the binoculars. I use mine regularly and it’s helped me get some great images. It’s also really easy to use and a great addition to any hiking kit!
Adam Hampton, Technical Advisor

Entangled Life: How Fungi Make Our Worlds (The Illustrated Edition)

This book includes an absolutely stunning collection of photographs that show the incredible detail, vibrant colours and sometimes strange features of many different types of fungi. I really love how the photographs zoom in on this often overlooked lifeform that is so difficult to appreciate fully with the naked eye.
Jo Graeser, Marketing Assistant

 

 

Browning Recon Force Elite HP5

I installed the Browning Recon Force Elite HP5 wildlife camera on a tree in our orchard AND WE LOVE IT! It shoots both stills and video, but my absolute favourite setting is the moving image function, especially paired with the no-glow night vision LED light during the night.
Sabine Lang, Customer Services Advisor

 

 

Biodiversity Net Gain: Key guidance and secondary legislation published

2024 is set to bring big changes to development law with Biodiversity Net Gain (BNG) measures becoming mandatory for most developments in England from 1st January. Small sites will not be subject to BNG laws until April 2024, while laws pertaining to Nationally Significant Infrastructure Projects (NSIPs) are expected to come into force in November 2025.

East Devon View by Alison Day via Flickr.
The Biodiversity Net Gain timeline to date

Following the Environment Act 2021 receiving royal assent in November 2021, provision was made for BNG to be introduced in England commencing in 2023. It was set out that gains could be delivered onsite, offsite or through the purchase of biodiversity credits.

In February 2023, Defra published its consultation response which provided more details on how BNG would be implemented, and suggested that the law would come into effect in November 2023. This has now been revised to January 2024.

At the end of September 2023, Defra and the Department for Levelling Up, Housing and Communities (DLUHC) published a timetable for the introduction of BNG. They also confirmed that it would only apply to new planning permission applications and not applied retrospectively to applications submitted prior to 1st January 2024.

This week, on 29th November, key guidance documents and secondary legislation were published by the Government.

Guidance documents

Step-by-step guidance has been provided for developers, land managers and local authorities which lead users through the BNG process.

Guidance for developers includes information on measuring the impact of a specific development on biodiversity, deciding how to achieve BNG, and ensuring that the 10% gain is maintained for at least 30 years.

Guidance for land managers looks at the options available for their land type and quantity, preparation and selling of biodiversity units, registering and recording the sale of the units to a developer, and the subsequent long-term management of the habitat.

Guidance for local authorities includes information on setting local policies to support biodiversity net gain, approving planning applications and biodiversity gain plans, reviewing the biodiversity gain plan, checking metric calculations and habitat surveys, checking developers selling excess on-site gains, checking the biodiversity gain sites register for off-site gains, monitoring BNG, and working with developers who wish to buy statutory biodiversity credits.

New housing estate in Stowmarket by Andrew Hill via Flickr.
Secondary legislation

Secondary legislation are laws that add more detail to primary legislation, allowing them to be enacted and enforced. In the case of BNG, these laws will provide the practical details required for measures to be implemented under the primary legislation of the Environment Act 2021.

Statutory instruments (SIs) are the documents created that must be laid in Parliament before the law can be changed. There are six BNG statutory instruments that will need to be approved by Parliament before they can be brought into effect on 1st January. These include:

The Biodiversity Gain (Town and Country Planning) (Consequential Amendments) Regulations 2023 – These regulations make amendments to the existing primary legislation on planning so that the BNG framework can be included.

The Biodiversity Gain Site Register (Financial Penalties and Fees) Regulations 2023 – This allows for fees to be incurred when registering land in the biodiversity gain register and financial penalties to be charged where incorrect information is provided.

The Biodiversity Gain Site Register Regulations 2023 – This sets out the details and eligibility criteria for the creation of a publicly available “biodiversity gain site register”. The register will be established and maintained by Natural England.

The Biodiversity Gain Requirements (Exemptions) Regulations 2023 – This sets out the categories of development that are exempt from creating biodiversity net gain.

The Biodiversity Gain Requirements (Irreplaceable Habitat) Regulations 2023 – This lists the habitats that are considered irreplaceable and for which the standard 10% requirement will not be applied.

The Biodiversity Gain (Town and Country Planning) (Modifications and Amendments) (England) Regulations 2024 – These regulations details how the BNG process will work within the existing planning application procedure. It also includes details of how appeals should be made.

The first two SIs were laid in Parliament on 30th November and will shortly be published on the Government’s legislation website. The remaining four still require approval by Parliament, although draft versions can be viewed using the links above.

Wild flower meadow by gailhampshire via Flickr.
Next steps

In January 2024 BNG will become mandatory for new applications for planning permission, with the exclusion of small sites* where BNG will not need to be delivered until April 2024, and NSIPs which will be covered from November 2025.

Having lost nearly half of our biodiversity since the 1970s, the UK is one of the most nature-depleted countries; we are ranked in the worst 10% globally for biodiversity intactness. Overall, 41% of species in the UK have declined in the last 50 years, with 26% of mammals at risk of extinction. We’ve lost 97% of our meadows, 90% of our wetlands and 80% of lowland heathland.

A scheme where development will no longer lead to biodiversity loss, but instead to net gain, is a step in the right direction to preventing further loss and helping to begin repairing our degraded environment.

* (Small sites are defined as (i) For residential: where the number of dwellings to be provided is between one and nine inclusive on a site having an area of less than one hectare, or where the number of dwellings to be provided is not known, a site area of less than 0.5 hectares. (ii) For non-residential: where the floor space to be created is less than 1,000 square metres OR where the site area is less than one hectare.).

Further reading

NHBS blog: Biodiversity Net Gain – Information about the scheme, including who will be affected, how it will be measured and potential barriers to its effectiveness.

NHBS blog: Biodiversity Net Gain: Credit Creation and Metric 4.0

Defra land use blog – articles on everything relating to BNG.

Government guidance on BNG

This week in biodiversity news – 27th November 2023

Climate Crisis

Plants may absorb more CO2 from human activities than previously thought, according to new research. More realistic modelling that considers critical physiological processes inside plants paints a more positive picture than previous predictions. The efficiency of carbon transport in plant leaves, the ability of plants to adjust to changes in temperatures, and how plants distribute nutrients in the canopy, often ignored in climate modelling, were examined in this study. Scientists stress that simply planting more trees is not a silver-bullet solution, but that the research does underline the importance of efforts to conserve existing vegetation.

Beach forest
Beech forest by Picccus via Flikr.

Red alerts have been issued as Brazil suffers an unprecedented heatwave. Temperatures are likely to remain 5°C above average for longer than five days and could pose a serious danger to human health. Rio de Janeiro recorded 42.5°C, breaking November records, and due to high humidity felt like 58.5°C according to authorities. The heatwave has been attributed to a combination of the El Niño climate phenomenon and climate change. The human impact of such extremes is significant with “unbearable” temperatures leading to sleepless nights, exhaustion, illness and death.

Pollution

Most bathing spots in English rivers and lakes have unsafe pollution levels, according to a new report. The campaign group Surfers Against Sewage took a sample of popular swimming and water sports locations and found that 60% had unsafe levels of pollution. This year across the UK, untreated sewage was discharged 399,864 times into waterways, resulting in a reported 1,924 cases of illness. The report highlighted the case of a physics teacher from Exeter who contracted an incurable disease known as Ménierè’s disease after surfing at Saunton Sands in Devon. 

flooded river
River Windrush by Dave_S via Flickr.

The high court has ruled that Defra’s failure to protect and restore water bodies is ‘unlawful’. Fish Legal and Pickering Fishery Association took the government to court over its river basin management plan for the Costa Beck, a small river in Yorkshire. They argued that the Environment Agency had failed to follow through with proposed action against polluters. The judge accepted discharges of pollution were contributing to the poor condition of the river and that the government and Environment Agency had failed in their mandatory duty to put in place measures to restore rivers under the Water Framework Directive.

Extinction Risk

Blue Whales have returned to safe havens in the Indian Ocean where they were wiped out decades ago. Underwater recordings made by researchers in the Seychelles revealed that the whales spend months in the region, suggesting that they may be breeding there. The discovery has been hailed as a “conservation win” given the decimation of whale populations by commercial whaling. More than 300,000 Blue Whales were killed by whalers in the southern hemisphere with around 30,000 killed in a single year during the 1930s. A crackdown on commercial whaling in the 1980s brought the species back from the brink of extinction; however, Blue Whale numbers remain a fraction of what they once were before the development of industrial whaling operations in the 20th century.

blue whale tail
Blue Whale surfacing by Kenny via Flickr.

New research has revealed that there is a significant threat of future waves of invasive species. Biological invasions can cause extinctions, spread diseases and cost trillions in damage and control. Researchers found that, on average, around 1% of all living organisms have been transported by humans somewhere in the world. The study indicates a huge potential for future biological invasions with an expected rise in associated socio-economic and environmental impacts.

Conservation

A hedgehog fence in Dorset is helping to protect threatened seabird chicks. Little Terns are one of the most threatened seabirds in the UK and the RSPB’s Chesil Little Tern Recovery Project seeks to reverse its decline. Trail cameras had revealed that hedgehogs had been eating Little Tern eggs. Given the protected status of hedgehogs, the project worked with the charity Hedgehog Friendly Portland to design a hedgehog fence and implement diversionary feeding. At least 45 Little Terns successfully fledged at Chesil Beach in 2023, compared with just three in 2021.

hedgehog looking out from a bush
Hedgehog by Kalle Gustafsson via Flickr.
Policy

The US will outline its nuclear fusion power strategy at COP28. John Kerry, the US Special Envoy on Climate Change, will set out the plan at the UN summit that will be held in Dubai from the 30th of November. The plan has been described as being the first international strategy for nuclear fusion power commercialisation. Nuclear fusion has long been looked at as a potentially limitless source of clean energy.


Read the last edition of Biodiversity News from the NHBS Blog which follows stories on endangered echidnas and an explosion in jellyfish numbers.

Why a trail camera makes the perfect gift this Christmas

Badger image taken with the Browning Spec Ops Elite HP5

Choosing the right gift for friends and loved ones can be a tricky affair, but for any keen wildlife watcher, and particularly one with a fondness for photography, a trail camera could be the perfect option. Here’s just a few reasons why we’re fans:

1. Catch a glimpse of wildlife that you wouldn’t otherwise be able to see
An obvious one perhaps, but trail cameras give you a wonderful opportunity to see and capture footage of all sorts of wildlife, particularly species that are easily startled or those that are active at times when we’d prefer not to be out and about (such as in the middle of the night) – a trail camera will allow you to observe the hidden lives all around you. The video below, recorded with the Browning Recon Force Elite HP5, is a wonderful example of what you can achieve right outside your back door.

2. See what animals are up to at times when you wouldn’t usually be watching
A perfect example of this is observing nocturnal animals. While the hardiest wildlife watcher might not be averse to wandering the fields and woods in the middle of the night equipped with the latest night vision gear, most of us would prefer to be tucked up in our beds. Trail cameras, with their night vision technology, can take images and videos of all the action so you can view it later at a time that’s more convenient. The video below shows a young fox passing through at night, recorded using a  Browning Recon Force Elite HP5 by Two J’s Wildlife Camera Set in Cornwall.

3. View behaviours and interactions that are usually unseen
While nothing beats an in-person encounter with a wild animal, such experiences are often brief and offer us limited insight into their life. Trail cameras, particularly those equipped with no-glow night vision technology (which means there is no tell-tale red flash when they take a photograph), are inconspicuous and will record footage for as long as there is movement within their capture range. This means that they are great for letting us experience a much broader range of behaviours and interactions. The video of the squabbling squirrels below was recorded by Two J’s Wildlife Camera Set in Cornwall.

4. Create stunning time-lapse videos
Almost all trail cameras can be programmed to capture images at a time interval of your choice, regardless of whether there is any movement detected. Using this function makes it possible to capture the subtle and gradual changes in the environment that would be difficult to observe in real time. Similarly, they can also be used to record behaviours that take place over longer periods, allowing you to view them at an accelerated speed.

A wren sitting on a branch in scrub.
A Wren photographed using the Browning Strike Force Pro X 1080

5. Share your findings with others
Whether you’re conducting research or simply want to know what’s happening in your back garden, the images and videos from a trail camera are perfect for sharing your findings with friends, family and colleagues. The quality of the photos/videos can be impressive, particularly when using models with high resolution lenses.

Browse the full range of cameras available from NHBS at nhbs.com.

For more advice about choosing a camera to suit your needs and budget, why not take a look at our Trail Camera Buyer’s Guide or contact us to chat with one of our experienced Wildlife Equipment Specialists.

In The Field: Browning Strike Force Pro X 1080

At NHBS, we offer trail cameras from a range of different manufacturers. Among these is Browning, who offer high quality at a reasonable price. The Browning Strike Force HD Pro X was one of our most popular cameras, and we regularly recommended it to customers. It offered ease of use, affordability, and excellent daytime and night-time photography. Browning regularly update their range of trail cameras, and given that the Strike Force has been on the market for several years, it has likewise been upgraded to a newer model, the Browning Strike Force Pro X 1080.

Trail camera with camouflage facing the camera with white background.
The Browning Strike Force Pro X 1080.

We wanted to test out the new Browning Strike Force trail camera to ensure it lives up to the standards of its predecessor. Here we will detail how we tested this camera and what we found.

Set up

To test the Strike Force, we headed to an estate in Devon that is managed to improve the condition of wildlife.

The set-up was relatively simple; we found a clearing between two areas of scrub where we suspected that animals would pass through, and secured the camera to a small tree at around waist height using a Python Lock.

The Strike Force comes with a camera strap included which works excellently, but we would recommend purchasing extra security options like a Python Lock if you are placing your camera in a public place. The strap and Python Lock can fit around a tree or a fence post and be tightened to hold the trail camera in position.

I set the camera to default settings and then changed it to photo mode and set the multi-shot option to three photos. I wanted to leave the camera out for a significant length of time, and I knew that videos would drain the battery and fill up the memory card rapidly. The multi-shot mode would hopefully allow me to get a few pictures of an animal moving through the frame.

Results

After three months in the field, the results yielded surpassed our expectations. We knew from talking with the conservation manager at the estate that we might get some decent pictures, but the range of species was unexpected.

The trail camera captured pictures of a range of bird species including one of a buzzard in flight.

Buzzard in flying past bushes.
A buzzard in flight.

We were lucky enough to get an amazing shot of a deer reaching for a leaf from the swaying branch of a willow tree as well as an excellent night time photo of a deer.

Deer reaching for a willow leaf.
A deer reaching for a willow branch.
Deer in a field at night. IR image.
A night-time image of a deer using IR photography.

A herd of Belted Galloway cattle were spotted passing through the clearing.

Cows with white stripe walking through a field with bushes around.
A herd of Belted Galloway cattle pass by the camera.
A herd of striped cows pass by the camera with calves in tow.
A Belted Galloway calf.

This herd of cows were curious and ended up nudging the camera with their noses, causing the camera to face towards a bush. We then caught a glimpse of a fox with the infrared camera mode. The image is a bit overexposed due to the vegetation in the foreground.

IR image of vegetation in the foreground and the faint image of a fox in the background.
A fox passes through the clearing.

Despite the overexposure, many of the IR pictures were excellent.

IR picture of vegetation in the foreground with two deer in the background passing through a clearing in the vegetation.
Deer at night.

We even managed to get a picture of what looks to be a Barn Owl on the ground at night. While not very clear due to the overexposure, it certainly confirms its presence in the area.

Vegetation with a barn owl on the ground in the background in IR photo mode.
A sighting of a Barn Owl on the ground.

The cows came back and pushed the trail camera even further to the right so that it was pointing into a bush. Fortuitously, we managed to get pictures of a mouse, a Robin and a Wren.

An IR photo of a mouse climbing a stick in foreground to the right of the image and vegetation in the background.
A night-time photo of what looks to be a Field Mouse.
Robin sitting on a branch surrounded by vegetation.
A Robin sitting in scrub.
A wren sitting on a branch in scrub.
A Wren sitting in the same spot as the Robin.

In addition to the species featured above, we also captured pictures of butterflies, squirrels, pheasants, Wood Pigeons, a thrush and a Great Tit.

Performance

When sorting through the 5,500 photographs captured, I found that the vast majority didn’t show any animals. I suspect that this could be remedied by better camera placement, although this may be unavoidable if there is a lot of vegetation around the area you wish to monitor. The major downside of taking so many photographs is that it takes a long time to sort through, and could potentially fill up your storage too quickly if you set your camera to video mode.

The image quality was impressive, with high-quality images and limited motion blur. The most notable issue was the level of exposure in the images, mainly at night. This was largely an issue because a herd of curious cows nudged the camera so it was facing the edge of a bush. This is unlikely to be a problem in the majority of cases and, prior to this, the night pictures were excellent.

Longevity

We placed the camera in the field in mid-July and collected it in mid-October. As such we were able to get around three months of footage. Image quality was set to 24MP with 1.5–2.5MB of storage used per image and around 5,500 images in total. This meant that we only used around 11GB out of a total of 32GB of storage available on the SD card. Remarkably, when the camera was collected it registered 94% battery, demonstrating the longevity of the Strike Force in the field, especially when set to photo mode. I suspect that this camera could have been left for another three months in the field without running out of storage or battery power.

Verdict

Overall, our experience demonstrates that the Strike Force Pro X 1080 is an impressive trail camera with high-quality day and night footage and impressive longevity. While it perhaps doesn’t quite reach the heights of the Browning Recon Force Elite HP5 or the Bushnell Core DS-4K in terms of picture quality, a more affordable price and impressive performance make this camera highly recommendable for both professionals and hobbyists.

No-glow alternative camera – Browning Dark Ops Pro X 1080

The Browning Strike Force Pro X 1080 is a low-glow camera meaning that the glow from the IR bulbs can be seen by both humans and animals. A no-glow camera may be the best option if you are looking for extra security or photographing an easily alarmed species. The Browning Dark Ops Pro X 1080 is an ideal no-glow alternative to the Browning Strike Force Pro X 1080. While a little more expensive, it is stealthier, and humans are less likely to notice it due to its no-glow flash. The only disadvantage is the shorter 24m flash range of the no-glow bulbs compared to the 36.58m flash of the Strike Force.

Trail camera facing towards the camera with camouflage coating with a white background.
The Browning Dark Ops Pro X 1080.
Accessories

The Python Lock is an ideal accessory for your trail camera. It won’t stop your camera from being damaged but it will prevent theft and keep your camera securely fastened to a tree or post. The lock is anti-picking, weatherproof and vinyl-coated. We used a Python Lock, and it held the camera in place until a herd of cows decided to turn it.

Image of a coiled up python lock.
Python Lock.

Spare memory cards and batteries are also highly recommended, especially if you are planning to use your trail camera on video mode. These additions will help you keep your camera operational for longer. Lithium batteries are highly recommended as, even when they have low charge levels, they supply sufficient power to the trail camera. Users of alkaline batteries may find that their trail camera isn’t performing well at night; this is because the batteries are not supplying sufficient power for the IR bulbs to function correctly.

 


Get your Browning Strike Force Pro X 1080 from our online shop.

Hawke Digi-Scope Smart Phone Adapter

Hawke DIGI-SCOPE SMART PHONE ADAPTER with a binocular lens attached being used to take a photograph of a black and white bird in the grass.

Getting into nature photography can be a daunting prospect. What camera do you buy? Which lenses do you choose, and what size should they be? How much should you spend? These are all questions that require a good bit of thought, and rightly so. However, what if you wanted to dip your toe in at the shallow end and use equipment that you may already have lying around to take decent photos at a fraction of the price? That’s precisely where the Hawke Digi-Scope Smart Phone Adapter comes in. I decided to put it to the test by taking images of local wildlife at a variety of ranges with two of Hawke’s spotting scopes and a pair of Kite binoculars. To do this, I used the Hawke Nature-Trek 20–60 × 80 and the Nature-Trek 13–39 × 56 scopes, and a pair of Kite Ursus 8 × 32 binoculars. 

Hawke have established a name for themselves as producing reliable and rugged optics for the entry to mid-level markets and this optical adapter fits nicely into that niche, giving anyone with an optical device the option to transform their optics into a camera lens, when combined with a smartphone camera. 


Out of the box – first impressions 

The adapter comes packaged with a small instruction manual and some small foam sticky pads to place around the aperture clamp and prevent damage to the ocular lens of the optics you are using. Made from lightweight ABS plastic, the adapter feels light in the hand but not fragile. Stated compatibility on the box is for eyepieces 23–50mm in diameter, so make sure that the optics you plan to use meet these specifications. There is also a minimum and maximum size for compatible phones (width 66–95mm), but most currently produced models should fit fine.

Front and back of the black scope phone attachment.

Ease of use  

The adapter is a simple piece of kit that is designed to fit around the ocular lens of a spotting scope, microscope, telescope or, most commonly, a pair of binoculars. The spring-loaded clamp then allows you to place your phones rear camera to the eyepiece and align them, in essence creating an inexpensive camera and physical lens arrangement. This will then allow your smartphone to take photos at ranges that the vast majority of devices on the market wouldn’t be capable of. Getting this alignment right can be quite fiddly but once found, the adapter holds fast, and the point of focus doesn’t drift. It’s important to try to remember to reduce/disable the auto focussing on the device as this can be at odds with the manual focus of the scope itself. Likewise, make sure to zoom the phone camera slightly to avoid giving a ‘scoped’ view to your photos, with a circular black border (see below).

Photograph taken through the scope attached to a phone of some ducks in a garden with a black ring around it in the shape of the lens. Photograph taken through the scope attached to a phone of some ducks in a garden without a black ring the shape of the lens around it, focused nicely and closely on the ducks.

In the field 

Testing the adapter involved setting it up on the window ledge of a bird hide and using it while combing along the River Dart, allowing tests over variable distances to look and capture at different focus points and ranges. I often found that target acquisition with the scopes was a bit of a lesson in trial and error as any hand movement through high magnification lenses will be exacerbated massively through the screen. However, this will be greatly reduced by using a lesser magnification or a stabilising structure such as a tripod (or a handy fence post). The use of a phone in this case proved crucial as the post- processing from the device helped to mute the amount of disturbance to the final image from this unavoidable shaking. While there was some aberration introduced to the final photos, it didn’t mar the result too much or overly distract from the images (see below). 

Photo of a mallard duck swimming on the river by some reeds taken through the Hawke smartphone adapter. Photo of a duck flapping its wings and splashing on the river by some reeds with a vignette image border taken through the Hawke smartphone adapter.

Using the adapter with a pair of binoculars was where the Hawke Digi-Scope really shone. Quick to acquire and quick to capture, the photos produced were, in my opinion, superb, making this an ideal tool for an enthusiast beginning their journey into nature photography. (see images below) 

Zoomed in photograph of a squirrel on a grey and red roof. Photograph of a crow on some grass which is scattered in autumn leaves.

While the adapter itself is a lightweight bit of kit, whatever you mount within it will add weight to the back of your optics and upset any built-in centre of balance – much as I found out when, after attaching the phone, the scope made a determined attempt at see-sawing off the bird-hide window ledge. When not attached to the optics, however, the adapter is small and portable, fitting easily into a pocket without any discernible bulk or weight. 

Taking pictures with the adapter was as simple as hitting the camera button on the phone and snapping away, making sure to adjust the focus using the scope/binoculars as needed (this took a bit of practice to get used to). I didn’t manage to get any images of animals moving at great speed (something a dedicated nature photography camera would have no issues doing) while using the scopes, as acquiring and holding onto the target while also focusing using the scope lent itself to more stationary birds (see image 9). The binoculars, on the other hand, were great for reactive type photography, albeit at much reduced ranges (e.g. image 10). 

Photograph of a brown duck standing on one leg scratching the underside of its wing with its beak stood on a log taken through a lens.
Image 9
Motion photograph of a crow taking off in flight from a patch of grass scattered in autumn leaves.
Image 10

 

 

 

 

 

 

Conclusions

While using the Hawke Digi-Scope, it is important to remember that the phone you use, the post processing that it does, and the settings you enable will all modulate the end result in some way, and this is an unavoidable part of using your phone to take images with a non-attached magnification device. Unlike an expensive camera with light meters and other tools, this setup will never quite produce a true to life image with no introduced imperfections.  

In terms of optics, the scopes performed well and were great in their own right; however, both the models I used were technically 1–2mm over the maximum specified eyepiece diameter. This was surprising as the mount seemed to fit fine (a little snug if anything), but also surprising as it begs the question as to why this adapter doesn’t fit the full range of Hawke products. This was not an issue with the binoculars as they have a much smaller ocular aperture. 

It is just as important to stress this wasn’t a test of the optics used but rather the adapter itself and, in that role, it performed very well. It held the phone securely and the rubberised touch points prevented slippage, keeping both the scope and phone lenses aligned. But, as stated before, this was a bit of a fiddly procedure.  

I do think that this adapter helps to bridge the gap between the more professional nature photography market and the more casual enthusiast who wishes to go and get some decent photos of what’s living in the area around them, and it will help to extend the reach of the average person’s smartphone camera by quite a distance. The speed of setup and lack of any frills really helps to make this adapter a portable, reliable workhorse or a spur of the moment image capturing tool. If you’re looking for an inexpensive bit of kit to add to your usual birding/hiking/survey gear alongside your pick of optics, this is the adapter for you.  


The Hawke Digi-Scope Smart Phone Adapter is available at www.nhbs.com/digi-scope

Author interview with Neil Middleton and Stuart Newson: Sound Identification of Terrestrial Mammals of Britain and Ireland

This groundbreaking book provides the reader with a unique and practical guide to collecting and using acoustic survey data to identify terrestrial mammals. Covering 42 species that can be found in Britain and Ireland, the text includes guidance on survey methods, analysis of sound recordings and details of appropriate software. As well as containing specific spectrogram examples for each species, the book allows the reader access to a downloadable sound library containing more than 250 recordings.

Neil Middleton is a licensed bat worker and trainer and is the owner of BatAbility Courses & Tuition, an organisation that delivers ecology-related skills development to customers throughout the UK and beyond. He has studied bats for over 25 years, with a particular focus on their acoustic behaviour (echolocation and social calls) and is the author of Social Calls of the Bats of Britain and Ireland, Is That a Bat?, and The Effective Ecologist.

Stuart Newson is a Senior Research Ecologist at the British Trust for Ornithology (BTO), where he is involved in survey design and data analysis from national citizen-science surveys. Stuart’s work on bioacoustics has included creating tools to identify European bats, bush-crickets and small mammal species from their ‘calls’. This resulted in the BTO Acoustic Pipeline, which integrates online tools for coordinating fieldworkers, processing recordings, and returning feedback.

Neil and Stuart recently took some time out of their busy schedules to answer some of our questions about their most recent book. In this Q&A we discuss the challenges involved in acoustic monitoring of mammals, the author’s hopes for the future of this area of study, and much more.


You each have a passion for acoustic monitoring – how did you come to be working together on this project?

Before we first met, Stuart was becoming interested in what else is recorded as ‘by-catch’ when you leave out a static bat detector to record bats. He had previously become interested in the sound identification of bush-crickets which are commonly recorded during bat surveys in southern Britain, and thanks to work that Neil was involved with (e.g. the first edition of the book The Social Calls of the Bats of Britain & Ireland), Stuart was becoming increasingly interested in bat social calls. At this time, he realised that small mammals are also quite commonly recorded as ‘by-catch’ during bat surveys, and was starting to appreciate that unless you had a good understanding of bat echolocation and social calls, there was scope for mis-identifying small mammals calls as being produced by bats.

When Neil started working on the book, Is That a Bat? A Guide to Non-Bat Sounds Encountered During Bat Surveys (ITAB), Stuart had already made available some online resources to help bat workers identify bush-crickets, which were able to feed into Neil’s book, and he also had some first recordings of some small mammal recordings that he was able to contribute to ITAB, which were very useful additions to the recordings that Neil had been gathering independently.

At about the same time, Stuart had met Huma Pearce, the third author on this book, and had started to work with her on an ‘edge-of-desk’ project to try and collect sound recordings for every species of small mammal in the UK. The aim was to try and collect many hundreds (ideally thousands) of sound recordings of every small mammal species in Britain and Ireland, which we wanted to build into bat classifiers to be able to assist with automatically identifying small mammals (as well as bush-crickets), when these are recorded as by-catch during bat surveys.

Working with Huma, and then Neil, to collect recordings for small mammals to feed into ITAB, and for Stuart to feed into his classifiers, we were now collecting a lot of recordings of small mammal species. After the publication of ITAB, we had learnt a lot more between us, so we wrote a more detailed guide to the sound identification of small mammals in Britain and Ireland, which was published in British Wildlife. After being approached by Pelagic Publishing, Neil was asked if he could author a book covering all terrestrial mammals in our part of the world. This was a much wider group than the one we had worked on up until that point. Neil agreed to the book idea, but only on the basis that Stuart and Huma would be involved as well. Thankfully both Stuart and Huma were ‘up for it’ and between us we managed to produce the book. I think we would all agree that if any one of us had not been involved, the job would’ve been considerably harder and taken much longer.

There currently exists a huge sound library of vocalisations of bats and cetaceans and their use in monitoring these species is now mainstream. Why do you think that this approach has not, so far, been used for other mammals such as those covered in your book?

We think that the main reason that so little has been done on the sound identification of terrestrial mammals (other than bats), is that for small mammals the call rate is quite low compared with other groups such as bats, and because the vocalisations can look like bat calls. I think until our various pieces of work, they have been largely overlooked. Until relatively recently, bat social calls had also been largely ignored by many bat workers, so there were few possibilities for noticing or identifying small mammal calls via that group. For audible mammal species, such as deer, there are alternative survey methods, such as visual surveys, and combined with this the call rate is again quite low, so without tools to help find these calls within large acoustic datasets it has been challenging to find and identify vocalisations by these species. In addition, before this book there was no resource or reference that people could use to help support the sound identification of audible mammals across the full range of species.

Added to this, we feel that the subject is difficult for many people in the non-bat mammal world to engage with and/or know where to start. Hopefully this book will open people’s eyes (and ears!) to the subject, thus meaning that more people will pay more attention to acoustic identification of these species, which will also mean that, overall, our rate of learning as a community will increase substantially as we begin to find out even more about the subject, including of course things that we didn’t appreciate at time of writing.

As well as providing the information and data required for species identification, do you think that acoustic data have the potential to tell us more about species behaviour, social interactions and population dynamics?

We think that there is huge potential for acoustic data to tell us much more about species behaviour, social interactions and population dynamics. As explored in the book, for some species we are able to relate particular call types to behaviour or status, but we still have a lot to learn for many of the species that are included in the book, in order to be able to understand in what situations particular calls are produced. By writing this book, we hope that this will inspire others to build on our work, and to accelerate an improvement in knowledge.

Which of the British terrestrial mammal species have you found the most challenging to study and why?

It is difficult to give a single answer to this one, but despite each of us having separate thoughts we would all agree on the following.

It was extremely difficult to collect or find existing sound recordings of rabbits and hares, because the call rate is extremely low. Huma (assisted by others) put lots of effort into rabbits, but sadly the results were zero. Separately Stuart tried to collect recordings of moles, by sinking microphones into the ground along mole tunnels, but he had no luck despite several weeks of effort.

Stuart would like to do more work on the sound identification of mustelids, which we feel we do not understand as much as we would like. We would all like to continue with more work on the small mammals, although we would each have different priorities in that respect. Shrews are of particular interest to us all, and Stuart in particular would definitely like to try and collect more sound recordings of Water Shrews.

Researchers have previously observed regional differences in the vocalisations of small birds recorded in various locations around Britain. Did you notice any geographic variations in the sounds produced by the mammal species you studied?

Personally, we haven’t seen much, if any, evidence of geographic variation in the recordings that we have looked at, but there could very well be regional differences. For some species it can be shown that differences occur at the individual level. This being the case, you could perhaps expect to see differences between social groups and, as such, regional and national differences too. At this point in time the amount of data we have is too small and hasn’t been collected with this in mind, and therefore we haven’t gone looking for an answer to this question ourselves.

There are currently several citizen science projects around the UK that the public can submit sightings to (such as those organised by the Mammal Society or apps such as iRecord). Is there currently anywhere that people can submit records resulting from acoustic data? Or somewhere they can submit their recordings in the hopes of building a library of sound files for each species as there is for bats?

Not that we are aware of, in the style that you have suggested by your question. However, if someone has heard (not seen) a species and they are happy that it is a diagnostic record for that species in a particular area, we would see no reason why a citizen science project would not accept the ‘sound’ as a valid record of the species being present at that location at that point in time. The key to this, however, is being confident that what was heard couldn’t be a similar noise made by something completely different – so we urge caution. It should also be remembered that in some cases sound identification may actually be more reliable than a visual record of a distant mammal, or a small mammal irrespective of how close it may be to the observer.

In a slightly different direction to your question, Stuart is best placed to talk about the use of such calls in building classifiers. His main interest in mammals has been to build a large sound library of known species recordings that can be used to build classifiers that can help identify the calls of different species automatically within recordings, with the book being secondary or a by-product of this. He believes that having such tools is essential for helping to find the calls of terrestrial mammals in large acoustic datasets, particularly for species where the call rate is low. The sound identification of all species of small mammals included in the book has been built into the ‘bat’ classifiers that comprise the BTO Acoustic Pipeline. The Acoustic Pipeline also includes specific classifiers for some audible species, including the Edible Dormouse. To the best of Stuart’s knowledge this is the first attempt from anywhere in the world to build classifiers for the sound identification of a complete assemblage of small mammals.

What are the next steps required to progress this research and what are your hopes for the future of this field of study?

There is still a lot to learn about the sound identification of mammals in Britain and Ireland, but there are some species groups on which we know we have done much less work and have less understanding than others. In particular, we think that acoustics could be useful for detecting the presence of mustelids (as we have already demonstrated for mice, rats, voles, shrews and dormice), but we would need to try and collect many hundreds (ideally thousands) of known species recordings, to be able to understand the full range of calls that a species can produce. This information could then also be used to create automated classifiers, thus enabling the possibility of efficient detection of species in this group from within large datasets.

As a longer-term ambition, Stuart is keen to work further on the wider sound identification of European mammals, and to extend the geographic and taxonomic scope of the BTO Acoustic Pipeline. Currently, he is able to identify small mammals in bat recordings from elsewhere in Europe at least to genus, by including similar closely related species from the UK in regional classifiers for other parts of Europe. However, he needs more targeted recording of known species to be carried out in order to be able to assign these identifications to species, and to be able to build classifiers that support the sound identification of mammals more widely across Europe.

Our hopes are that this book inspires others in Europe (and further afield) to work on the sound identification of mammals, and more widely to see the opportunities that understanding acoustics can offer.


Sound Identification of Terrestrial Mammals of Britain & Ireland is published by Pelagic Publishing and is available at nhbs.com.