The Bizarre Biology of Bdelloid Rotifers

Bdelloid rotifers are tiny filter-feeding animals that live in freshwater habitats worldwide: in ponds, streams and lakes, even where the water sometimes dries up or freezes, like moss, soil, puddles and ice sheets. They are among the most resilient of all animals, and also have some of the strangest biology.

Unlike other known animals, all bdelloid rotifers are females, with no sightings of males in the 300 years since they were discovered — rotifer mothers lay eggs that hatch into genetic copies of themselves, without sex, sperm or fertilisation.

Another surprise is that bdelloid rotifers have been stealing DNA from other organisms on a massive scale by a process called horizontal gene transfer, so that about one in ten of their genes have been copied from different kinds of life, including bacteria, fungi and even plants.

Among these stolen genes, we recently discovered that bdelloid rotifers have copied dozens of recipes for antibiotics from bacteria, which the rotifers now use to fight off their own diseases. This unusual defensive strategy could lead to short-cuts in the race to develop new drugs against antibiotic-resistant infections in human patients, and might also shed light on the strangely sexless lifestyle of these animals.

Q&A with Dr Chris Wilson

Dr Chris Wilson is a Lecturer in Biology at the University of Oxford. Originally from Kent, he completed undergraduate studies at St Anne’s College and a doctorate at Cornell University in the USA before returning to the UK, where he has held research fellowships and teaching positions at Imperial College London and St Hilda’s College, Oxford. He is interested in the causes and consequences of sexual versus asexual reproduction, which he addresses by studying the evolution, ecology and genomics of microscopic freshwater rotifers and their natural enemies, particularly pathogenic fungi.

1. If rotifers reproduce asexually, how do scientists define species?

We usually think of a species as a group of organisms that are capable of reproducing to produce fertile offspring. It turns out that even though rotifers don’t reproduce sexually, it is still possible to robustly define them into discrete species. First and foremost, this can be done based on morphology. Namely, there are consistent, clustered morphological forms which exist within the diversity of rotifers. These clustered forms are distinct from one another – it’s not just a continuous spectrum of variation. We think these discrete forms arise because the environment selects for particular shapes of rotifers’ body parts (e.g. their so-called ‘teeth’ and ‘toes’). The most suitable of these morphological forms are then preserved under natural selection. For greater precision, or as a supplement to the morphological species concept, DNA can be used. Sequencing of bdelloid rotifer DNA has corroborated that there are indeed distinct, clustered genetic sequences within the broader spectrum of variation, matching what we might generally refer to as species.

2. You mentioned rotifers stealing genes from bacteria, protists and plants. Do they also steal genes from other animals?

It’s a great question. It’s very hard to tell if rotifers have been stealing genes from other animals. In contrast, plant DNA, for example, sticks out like a sore thumb amongst the genome of a rotifer – it is clear it doesn’t belong there. Other animal DNA, if hidden amongst a rotifer’s genome, would be much less obvious. We would love to look more closely at this question. My personal guess, for what it’s worth, is that bdelloid rotifers are almost certainly stealing genes from other animals. A harder, follow-up question, would be which genes are being stolen, and what are these new genes doing?

3. How hard is it to identify rotifer species?

Generally, it is very difficult. For a start, bdelloid rotifers are soft-bodied, which means that their body parts (particularly the so-called ‘wheel organs’) are often tucked away internally and not visible. It is these body parts which are essential to view for species identification. In practice, this means you must be fast, i.e., make every effort to minimise the time taken between extracting a sample containing rotifers in the field and viewing it under the microscope in the laboratory. Preserving rotifers is an even harder job because as soon as they are disturbed they contract, hiding their characteristic features internally. The only identification key for rotifers is in German and is around 50 years old, which adds another challenge. There are only a handful of people around the world who are really good at identifying bdelloid rotifers to species level. Some of the other rotifer groups with harder bodies are more easily identified.

4. Has the process of horizontal gene transfer generally been consistent within species?

Yes, generally it has been. This is because most of the horizontal gene transfer in bdelloid rotifers occurred a very long time ago. Horizontal gene transfer in rotifers is not quick; we estimate that it tends to happen only around once every 100,000 years. Rotifers have, of course, been around for several millions of years so over this time they have nevertheless accumulated a lot of so-called ‘foreign’ genes. Indeed, horizontally gained genes make up around 10% of bdelloid rotifer genomes, i.e., 1 in 10 bdelloid rotifers genes isn’t even an animal gene! Because of how slow this process is, many bdelloid rotifer species share the same horizontal genes which arrived hundreds of thousands, or even millions, of years ago. But, simultaneously, there are handfuls of genes which are unique to particular species and therefore have arrived more recently. These clusters appear to be consistent amongst individuals within a species.

5. How exactly does horizontal gene transfer in bdelloid rotifers work?

We don’t know! One of the great problems of horizontal gene transfer in rotifers being so rare (occurring once every 100,000 years or so) is that nobody has actually witnessed it happen. Several scientists have tried to make rotifers ‘eat’ DNA to see if it is copied into their genome, but none has seemed to stick. There are various hypotheses as to how the process works. One theory is that during desiccation, the rotifers’ genome becomes damaged, and may, during the repair stage, incorporate new genes from surrounding environmental DNA. The issue with that theory is that there are bdelloid rotifers which do not survive desiccation which still have horizontal genes. An alternative hypothesis is that it’s to do with ‘jumping DNA’ – pieces of DNA which can jump from one place in the genome to another, and perhaps even transfer from one organism to another. But while lots of animals have jumping DNA, only the rotifers have gained thousands of genes horizontally. For now, it’s a mystery, but it’s a really active research area in this field, and we’d love to know the answer in the future.

Literature References

  1. Wilson et al. (2024) ‘Recombination in bdelloid rotifer genomes: Asexuality, transfer and stress’: https://www.sciencedirect.com/science/article/pii/S0168952524000283
  2. Wilson and Sherman (2010) ‘Anciently asexual bdelloid rotifers escape lethal fungal parasites by drying up and blowing away’: https://www.science.org/doi/10.1126/science.1179252
  3. Wilson et al. (2024) ‘Tiny animals use stolen genes to fight infections – and could fight antibiotic resistance too’: https://theconversation.com/tiny-animals-use-stolen-genes-to-fight-infections-and-could-fight-antibiotic-resistance-too-234737

Further Info

entoLIVE

entoLIVE webinars feature guest invertebrate researchers delving into their own invertebrate research. All events are free to attend and are suitable for adults of all abilities – a passion for invertebrates is all that’s required!

entoLIVE is delivered by the Biological Recording Company in partnership with the British Entomological & Natural History Society, Royal Entomological Society and Amateur Entomologists’ Society, with support from Buglife, Field Studies Council and National Biodiversity Network Trust.

The entoLIVE programme is delivered by Biological Recording Company and receives sponsorship from the following organisations:

Learn more about British wildlife

Check out our events on Eventbrite

Falling through the Cracks: iNaturalist Invertebrate Records in the UK

iNaturalist is a rapidly growing source of biological records in the UK: In 2024, over 44,000 users generated more than 1.6 million records using the platform. With the number of records generated set to increase into the future, integrating iNaturalist into UK recording systems is essential. As of 2020, iNaturalist records meeting certain criteria have been exported into iRecord, where it is hoped they will be reviewed by verifiers.

For some groups of invertebrates, however, it would appear a large proportion of iNaturalist records are not being reviewed. One explanation for this is that concerns with the data quality of records are leading verifiers to deprioritise iNaturalist as a source. All iRecord verifiers are volunteers with large workloads and limited time, so this may be justified if the data quality of iNaturalist records is indeed lower. However, this has never been quantified.

This research sought to address this, quantifying for the first time the extent of data quality concerns across taxonomic groups of UK non-marine invertebrates. Results suggest that there are indeed systemic data quality issues with iNaturalist records, though the greatest issues in reality are not always the same issues people perceive to be greatest. Many such issues will be fixable through education and outreach to iNaturalist users.

Q&A with Joss Carr

Joss Carr is an entomologist, naturalist and biological recorder who, having just finished his MSc in Biodiversity and Conservation at Queen Mary University of London and the Royal Botanic Gardens at Kew, is now working for the Biological Recording Company as a Junior Naturalist. Joss is also a prolific user of the citizen science biodiversity platform iNaturalist. His MSc Research Project, the subject of this talk, focused on quantifying data quality concerns with biological records of invertebrates derived from iNaturalist.

How do I change my record licenses?

One of the key points I touched on in the webinar is the importance of iNaturalist users setting up their licenses in a way that permits unrestricted sharing of their observations with biodiversity data aggregators and conservation organisations in the UK. In practice, this means setting your licenses to CC-0 (public domain) or CC-BY (attribution). The default license (CC-BY-NC, an attribution non-commercial license) is not recommended, as this license greatly restricts data use. Indeed, many data users will wholesale ignore all records with this license as it would be technically illegal for them to use them. Fortunately, iNaturalist makes changing your licenses straightforward. The easiest way to do it is in the website (i.e. not the app), by going to Account Settings -> Content & Display -> Licensing, and then changing the default licenses for your observations, photos and sounds to CC-0 or CC-BY. Note that these three aspects are licensed separately. The most important one to change is your record license, but ideally change your photo and sound license too. The choice between CC-0 and CC-BY is a lot less important, instead simply reflecting whether you wish users of your data to credit you by name when they do so (CC-BY) or not (CC-0).

How do I change the name associated with my iNaturalist account?

Another key thing for iNaturalist users to do, which I stressed in my talk, is to change your display name on iNaturalist. The reason why this is important is because many users of iNaturalist data require a ‘proper’ name of the recorder to be associated with the record, primarily so they can learn to recognise and trust competent recorders. A ‘proper’ name is in the format [forename] + [surname]. Records associated with usernames or initials are far less likely to be accepted or used (although see my answer to the next question below). Changing your display name is, again, easiest within the iNaturalist website. Go to ‘Account Settings’ -> ‘Profile’ -> ‘Display Name’ and change this to your first name and surname.

What is the debate about recorder names?

A hot topic! Before the advent of photography-based biological recording, the name of the recorder responsible for the biological record was an essential part of each record because it allowed for the trustworthiness of the record to be assessed based on the known competence of that recorder. This legacy of traditional biological recording continues today; many data aggregators continue to value recorder names as crucial parts of biological records. Recently, however, some have begin to question the necessity of providing this piece of information if a unique user ID and photo are already provided. Providing one’s real name comes with privacy and security concerns, not least given individual’s records tend to be associated with sites they frequent, or even their homes and gardens. With a verifiable photo and unique user ID, and a means through which to contact the recorder, everything needed to assess the correctness of the record is arguably already provided. Necessitating the provision a recorder’s true name may not provide any supplementary value, but rather may instead put privacy-conscious recorders off from submitting records.

What happens to observations that never reach Research Grade on iNaturalist?

Short answer – almost certainly nothing. By which I mean these records are unlikely to be used to inform biodiversity science and conservation in the UK. That is unless, of course, a researcher or conservationist specifically goes to iNaturalist in search of these ‘unverified’ records. For many taxonomic groups on iNaturalist, a very large proportion of observations fall into this box; i.e. they have not made it to Research Grade. This phenomenon occurs for two main reasons: either (1) in most cases the photos provided are insufficient to confirm a species-level identification, and/or (2) there are not enough people actively reviewing and identifying incoming observations for the group on iNaturalist. This latter explanation emphasises a key call to arms – we need more taxonomic specialists on iNaturalist! If you have detailed knowledge of a group of organisms and know how to separate similar species from one another, please, contribute to iNaturalist! Your efforts will be greatly appreciated by the community.

What is being done to redress the data quality issues identified in your research?

It’s a work-in-progress area. My research represents the first time data quality concerns with iNaturalist records in the UK have been quantified. So we now have a clear demonstration of the scale of the problem. It’s now time to turn towards finding solutions. I personally believe this is primarily an awareness problem, i.e., that the main issue is that most iNaturalist users are unaware of the importance of data quality. It’s also partly going to be an effort of changing perceptions, although hopefully that should naturally follow once data quality begins to be cleaned up. I personally advocate for a dual bottom-up/top-down approach whereby simultaneously (1) iNaturalist users take responsibility for cleaning up their own data quality and spreading the word to others to do the same and (2) the organisations responsible for biodiversity data management in the UK provide assistance and guidance to support this process as much as possible. The National Biodiversity Network (NBN) have been leading this work so far within the iNaturalistUK ‘node’, and I hope to contribute to their work over the coming years through outreach campaigns and further research.

You can read Joss’ MSc Research Project final report here: https://drive.google.com/file/d/1CjWjprMYHAUkSsxgv9h1bu4UHXsAULJa/view?usp=sharing

Literature References

  1. Mesaglio (2024) ‘A Guide to iNaturalist: An Australian Perspective’: https://ala.org.au/app/uploads/2024/04/A_Guide_to_iNaturalist_Apr2024-1.pdf (N.B. the majority of the guidance here is internationally applicable)

Further Info

entoLIVE

entoLIVE webinars feature guest invertebrate researchers delving into their own invertebrate research. All events are free to attend and are suitable for adults of all abilities – a passion for invertebrates is all that’s required!

entoLIVE is delivered by the Biological Recording Company in partnership with the British Entomological & Natural History Society, Royal Entomological Society and Amateur Entomologists’ Society, with support from Buglife, Field Studies Council and National Biodiversity Network Trust.

The entoLIVE programme is delivered by Biological Recording Company and receives sponsorship from the following organisations:

Learn more about British wildlife

Check out our events on Eventbrite

Recording Beetles at Hogsmill Valley

Blog post by Joss Carr

This article recounts the Beetle Field Recorder Day held at Hogsmill Valley on Wednesday 4th June.

Nestled along the banks of the Hogsmill River, one of London’s few chalk streams and a tributary of the Thames, are a series of interconnected nature reserves collectively known as the Hogsmill Valley. Our mission: Survey these reserves for beetles. It was an ambitious plan, with four sites to hit over the course of the day. We would start in the south, at Six Acre Meadow, and work our way north, ending at Rose Walk. 16 naturalists rallied for the task, representing a range of experiences from beginner to dedicated enthusiast. The party was helmed by beetle specialist Wil Heeney. Equipped with sweep nets, trays, pots and cameras, we set out.

Participants gathering for a briefing at the start of the day [CC-BY Joss Carr]

Site 1: Six Acre Meadow

The day immediately got off to a strong start at our first site: Six Acre Meadow. The dense, lush grass of the meadow was alive with insects on our visit, including plenty of beetles. Sweep netting quickly yielded several soldier beetles (family: Cantharidae), including Cantharis fusca, C. lateralis and C. figurata, as well as the common Malachite Beetle (Malachius bipustulatus) and its slightly less well-known cousin Cordylepherus viridis. The distinctive, shining green Swollen-thighed Beetle, Oedemera nobilis, was also found. By far the most abundant beetle, however, was the grey-green Oedemera lurida, which close to every single participant managed to find within a few minutes.

Getting to work in Six Acre Meadow [CC-BY Joss Carr]

As can be expected in any meadow, ladybirds (family: Coccinellidae) were also abundant, with the 24-spot Ladybird (Subcoccinella vigintiquattuorpunctata) particularly prolific. 7-spot Ladybird (Coccinella septempunctata), 2-spot Ladybird (Adalia bipunctata) and mating 22-spot Ladybird (Psyllobora vigintiduopunctata) were also found.

Two 22-spot Ladybirds (Psyllobora vigintuduopunctata) on Meadowsweet [CC-BY Joss Carr

The meadow also proved very good for weevils. The bulky and prickly Sciaphilus asperatus, the neat black Rhinoncus perpendicularis and the extravagantly patterned Nanophyes marmoratum were all found from sweeping the grass. Zacladus exiguus was swept from a large patch of Cut-leaved Crane’sbill (Geranium dissectum) on the meadow edge, upon which it feeds.

The weevil Sciaphilus asperatus [CC-BY Joss Carr]

In terms of smaller beetles, two nice flea beetle species were found from sweeping: the yellow Aphthona lutescens and the pitch-black Chaetocnema concinna. Flea beetles are a tribe (Alticini) within the family Chrysomelidae (the ‘leaf beetles’) which are distinctive for their greatly enlarged hind femorae (essentially their ‘thighs’) which are adapted for jumping; hence ‘flea beetle’ (see photos below). Though very common, they are a challenging group to identify as most are very small (<5 mm) and often require dissection to identify.

Aphthona lutescens (left) and Chaetocnema concinna (right), two flea beetles [CC-BY Joss Carr]

Ironically, likely the best find from our visit to Six Acre Meadow in terms of rarity was not a beetle but two leafhoppers (family: Cicadellidae). What immediately caught the eyes of a few participants upon arriving in the meadow was a large patch of Meadowsweet (Filipendula ulmaria). Sweeping this yielded two leafhopper species which are found only on Meadowsweet as a host plant: the small and spotted Eupteryx signatipennis and the larger Macrosteles septemnotatus. Due to their strict requirements for large patches of their host plant, both these hoppers are rarely recorded. As per the NBN Atlas, the day’s records represent the first ever London record for E. signatipennis and the second ever for M. septemnotatus.

With our ambitious schedule for the day, it was soon due time to depart Six Acre Meadow and head onwards. In the ever-distracted fashion of naturalists, however, a shout from one participant standing in a bramble bush quickly brought everyone over. She had noticed several jewel beetles (family: Buprestidae) flying between the bramble flowers. Most infamous for being wood-boring pests of timber plantations, jewel beetles are also – as the name suggests – stunningly beautiful beetles that, with their metallic and iridescent colouring, resemble jewels. The jewel beetle found on the brambles was a gorgeous metallic green one: Agrilus angustulus.

Agrilus angustulus, a jewel beetle (family: Buprestidae) [CC-BY Joss Carr]

Site 2: Southwood Open Space

Despite being little more than 300 metres north of Six Acre Meadow, our second site – Southwood Open Space – was distinctly different in character. Where Six Acre Meadow had been lush and green, Southwood Open Space, like many parks around London this summer, was very dry. The vegetation character of the meadow was also notably different. Where tufts of Meadowsweet (Filipendula ulmaria) and Meadow Crane’s-bill (Geranium pratense) had dotted Six Acre Meadow, Southwood Open Space’s most notable plant was the surprisingly abundant Wild Onion Allium vineale.

The beetles found, however, were more or less the same. Among the larger beetles, novelties from the grassland itself were limited to the fourth soldier beetle species of the day in Cantharis decipiens, the 14-spot Ladybird Propylea quattuordecimpunctata and the green weevil Phyllobius roboretanus.

Phyllobius roboretanus [CC-BY Joss Carr]

Perhaps the most interesting beetle find at this site was the co-occurrence of three species of very similar Protapion weevils swept from a large patch of White Clover (Trifolium repens). The Protapion weevils are a tricky bunch, with 10 British species all found on clovers and all black with orange legs. To distinguish them is usually a microscopy job, looking at details of the different segments of the legs as well as the shape of the rostrum (the weevil’s ‘nose’).

Likely the ‘rarest’ find at this site was Phalacrus corruscus, a tiny (2mm long) shiny black beetle and a member of the family Phalacridae (the ‘Shining Flower Beetles’), a family of beetles which are often found in sweep net samples. Many refrain from collecting these species given the high-power microscopy needed to identify them through examining details of the legs and elytra, however when one does succeed in doing so you are often met with a relatively ‘rare’ find (in the sense of an infrequently recorded species). The day’s record was the fifth ever for London.

Besides the meadow itself, a brief shake-down of an English Oak (Quercus robur) and Hybrid Crack Willow (Salix × fragilis) on the edge of the field yielded a few nice species including the leafhopper Alebra albostriella and the plant bug Phylus melanocephalus from the former, as well as the ever-present Willow Flea Beetle Crepidodera aurata from the latter.

Sharing finds from Southwood Open Space [CC-BY Joss Carr]

Site 3: Elmbridge Meadows

Hugging the Hogsmill River for just shy of a kilometre, Elmbridge Meadows – our next site – acts as a crucial ‘green corridor’ in the borough. What it lacks in width it makes up for in interesting habitat. The Hogsmill is lined here with gorgeous old willows (Salix spp.) and poplars (Populus spp.), and a diverse sward of shrubs line the footpath as it snakes north. It was here that many of the days’ most exciting finds were made.

The first of these excitements was a moth! And if your natural reaction to that is to question why a moth deserves mention in a blog about beetles (fair enough), that is because this was not just any old moth, but rather a Hornet Moth (Sesia apiformis). Without much question at all this is one of the most charismatic and attractive of all the British Lepidoptera, and quite rare too. The Hornet Moth is a clearwing moth, part of the family Sesiidae which features 16 UK species which are at most uncommon and several of which are stupidly scarce. Without concerted search effort using pheromone lures, the average naturalist in the UK can expect to see only a handful of these gorgeous moths in a lifetime.

As you might guess from the name, Hornet Moths are Batesian mimics of Hornets (Vespa crabro). In flight or from a distance you could quite easily be fooled, especially because they are a similar size. Adult Hornet Moths are generally only ever found on or near poplars (Populus spp.) – the larvae feed on the wood pulp at the base – and almost exclusively in June. That is to says the conditions we saw ours were exactly right. Check out this beauty!

Hornet Moth Sesia apiformis [CC-BY Joss Carr]

Back to beetles now, and the theme of mimicking black-and-yellow buzzing things nevertheless continued. Sweeping of Hogweed (Heracleum sphondylium) umbellifers alongside the riverbanks yielded another gorgeous insect: the Wasp Beetle (Clytus arietus). This is another species which is not often seen given it is reliant on good quality deadwood habitat. In this case it mimics wasps in the genus Vespula (i.e. the Common and German Wasp).

Wasp Beetle Clytus arietis [CC-BY Joss Carr]

Other beetle highlights from Elmbridge Meadows included:

  • Two common leaf beetles (family: Chrysomelidae): Gastrophysa viridula found on dock (Rumex sp.) and Plagiodera versicolora found beneath willow (Salix sp.).
  • The first ground beetle (family: Carabidae) of the day: the common Harpalus affinis, found running across the footpath
  • The fifth soldier beetle (family: Cantharidae) of the day, Cantharis pellucida, found on a bramble thicket
  • The metallic blue flea beetle Altica lythri, swept from vegetation along the riverbank and dissected under the microscope for identification
  • The long-nosed weevil Ceutorhynchus obstrictus
  • A nice selection of host-specific apionid weevils swept from Common Mallow (Malva sylvestris): Aspidapion aeneum, Aspidapion radiolus, Malvapion malvae and Pseudapion rufirostre
Ceutorhynchus obstrictus, a weevil [CC-BY Joss Carr]

The only other thing of note in Elmbridge Meadows on our visit was the remarkably large numbers of Harlequin Ladybirds (Harmonia axyridis). Close to every single leaf of the bramble thicket which lined each side of the footpath had either a larva, adult or cluster of eggs on it. It seems to have been a very productive year for the species.

After a quick lunch where we delighted in watching damselflies dance over the river, we headed out of Elmbridge Meadows and towards the last site for the day: Rose Walk.

Inspecting a dense thicket of Common Nettle (Urtica dioica) and Hogweed (Heracleum sphondylium) along the footpath in Elmbridge Meadows [CC-BY Joss Carr]

Site 4: Rose Walk

By this point – having been out and about for nearing 5 hours – fatigue was beginning to set in, and so recording levels dropped a little such that only the most interesting specimens garnered attention. Fortunately, a few last-minute beetle delights were nevertheless offered up by Rose Walk. Fittingly, the first of these was a Rose Chafer (Cetonia aurata), with its gorgeous iridescent green elytra shining in the afternoon sun. The chafer beetles, of which Cetonia aurata is the most common and well-known, represent several subfamilies within the family Scarabaeidae. They are a nice group of beetles to get to know as a beginner as all the species are large and relatively easy to tell apart once learnt. For those interested, Wil Heeney – who led the Field Recorder Day – is running a training webinar about these beetles, including the Rose Chafer, on the 15th of September. Sign up here!

Rose Chafer Cetonia aurata [CC-BY Joss Carr]

Given how dry this summer has been in southern England, deadwood has fallen off most naturalists’ radars. Nevertheless, a particularly promising log was noticed right towards the end of the day and, as if to see us off, yielded one of the largest and most loved of the British beetles: the Lesser Stag Beetle (Dorcus parallelipipedus).

Lesser Stag Beetle Dorcus parallelipipedus [CC-BY Joss Carr]

All in all, the Field Recorder Day was a resounding success, with 16 participants generating 137 records of 89 species in total, including 64 records of 42 beetle species. Records were spread across the four sites as follows:

  • Six Acre Meadow: 43 records of 41 species (including 22 records of 22 beetle species)
  • Southwood Open Space: 39 records of 30 species (including 22 records of 16 beetle species)
  • Elmbridge Meadows: 42 records of 34 species (including 16 records of 13 beetle species)
  • Rose Walk: 11 records of 9 species (including 6 records of 4 beetle species)

Thanks very much to everyone who attended and recorded beetles and other interesting species. It was a very fun day and we hope to see people again at similar future events, which you can sign up for here.

Smarter Surveying: Digital Solutions for UKHab and BNG Surveys

Discover how digital innovation is streamlining habitat surveys and Biodiversity Net Gain (BNG) delivery in this free webinar with environmental professionals. Learn how Coreo, a digital survey platform, can enhance data accuracy, reduce admin time, and improve collaboration through real-world consultancy experience and cutting-edge digital tools.

This blog is ideal for ecologists, environmental consultants, local planning authorities, Local Environmental Record Centres and anyone involved in UKHab or BNG workflows. It features two recorded presentations:

  1. Streamlining UKHab & BNG Surveys with Coreo with Dave Kilbey (Natural Apptitude)
  2. From Field Notes to Fully Digital: Embracing Coreo for UKHab & BNG Surveys with Owen Crawshaw (The Ecology Co-op)

Streamlining UKHab & BNG Surveys with Coreo

Dave Kilbey (Natural Apptitude)

Dave Kilbey demonstrates how Coreo transforms UKHab and BNG surveys by boosting accuracy, ensuring compliance, and saving time. Learn how to seamlessly export data into the Biodiversity Metric and Defra’s condition assessment workbook, and discover how full data transparency with LPAs and clients can reduce follow-ups and build trust.

Dave Kilbey is the Founder and CEO of Natural Apptitude. Natural Apptitude is the UK’s leading producer of data collection software for the ecology and conservation sectors. Its citizen science orientated projects include the Big Butterfly Count, Mammal Mapper and INNS Mapper. Its data collection platform, Coreo, supports hundreds of ecological consultancies and other organisations with field-based surveys, including the UKHab Survey/BNG. Dave has always been passionate about conservation and believes technology has a key role to play in reversing the loss of biodiversity. Outside of work his main interests include birds, botany, bugs and his two white, miniature schnauzers.

What support is available for getting started with Coreo and after?

The best way to get started with Coreo is to book a free demo with our team. We’ll set you up with a 30-day free trial of Coreo, and during that trial, you’ll receive a series of onboarding emails to help you get up and running. If you’re a large team, that’s fine too – we have no limit on the number of people that can attend a demo and take part in the free trial.

You can also find more support resources in the Coreo Knowledgebase, which contains a comprehensive range of training videos, written documentation, and FAQs.

We also offer additional training, consultancy, and other services such as bespoke survey building. Feel free to reach out directly to learn more.

Once you become a subscriber, Coreo has a highly rated Support Desk where you can raise a ticket if you have any questions.

What makes Coreo different to alternative platforms?

While several other platforms offer digital solutions for data collection, Coreo excels by focusing on both functionality and user experience. It has been designed to be as powerful as the products originating from GIS systems but without requiring all the indepth GIS and technical knowhow. We work closely with our clients and understand what people really need in the field and back in the office. Key elements include:

  • Accessibility and intuitive design: Coreo’s intuitive interface and short learning curve mean you can get your team up and running quickly. 
  • Designed for and with ecologists: Coreo has been built primarily to serve the needs of people collecting ecological and other environmental data. It has been developed in close collaboration with ecologists, and the UKHab/BNG survey is a partnership with the lead author of the UKHab classification. This ensures the software continually evolves with the needs of ecologists.
  • A Customisable Platform: Coreo offers a range of pre-built survey templates, including those for various specific species, breeding & wintering birds, and the UKHab survey. You can also easily customise any template (apart from UKHab) or create bespoke surveys from scratch. No coding experience is required.

What does the UKHab survey license get you?

The Coreo UKHab survey template was built in collaboration with the lead authors of UKHab. The license gets you access to this product and all of the associated functionality in the Coreo Admin Area, with which you can carry out full UKHab & BNG pre-survey and baseline surveys, with post-development to come soon. The template includes:

  • Advanced GIS tools: These have been designed to make UKHab/BNG surveys accurate and easy to undertake in the field.
  • Integrated UKHab codes and assessments: The app has all UKHab codes and condition assessments built in. As you select a code, the app automatically displays the correct condition assessment, saving you time and reducing errors.
  • Species recording built in: The survey includes the ability to record quadrat and general species data as part of the survey process. The entire botanical list for the UK along with all UK bryophytes and lichen species is built in.
  • Easy map creation and data export: Coreo produces site maps automatically and gives you access to export your data directly to the Metric Calculation Tool and official Condition Assessment Workbook, removing the need for manual data transcription and ensuring a smooth workflow from field to report generation.
  • Compatibility with other software: Coreo provides you with several export options which are compatible with other software; for example, you can export Shapefiles, GeoPackage or GeoJSON for use in QGIS or ArcGIS.

Do you require GIS experience to use Coreo?

No, Coreo has been designed to be accessible to everyone and user-friendly by design. It integrates easy-to-use, intuitive GIS tools, allowing you to streamline your workflow and ensure data accuracy while you’re in the field. Here are just a few of the time-saving GIS and mapping tools in Coreo:

  • Drawing tools: Create precise habitat features by dropping points or by using a stylus if you have one.
  • Overlap Avoidance and snapping: Powerful tools designed to eliminate overlaps and gaps at the point of capture and/or retrospectively.
  • Custom Layers: Add custom map layers for reference, such as aerial photography.
  • Offline maps: Save base maps so that you can work entirely offline if you need to.

Can you buy a Coreo license for an organisation?

Coreo licenses apply to individual users, rather than organisations, so you will pay based on the number of people within the organisation that use it. You can explore the pricing options on the Coreo website.

If your organisation is a charity, you are entitled to a discount. If this applies to you, please get in touch with the team.

From Field Notes to Fully Digital: Embracing Coreo for UKHab & BNG Surveys

Owen Crawshaw (The Ecology Co-op)

Principal Ecologist Owen Crawshaw explores a consultancy’s journey from traditional methods to a streamlined digital workflow using Coreo. Discover the key benefits of going paperless for Biodiversity Net Gain (BNG) and UKHab surveys, illustrated with real-world project examples. The session also addresses current technological limitations and the future of digital ecology.

Owen Crawshaw is a Principal Ecologist at The Ecology Co-op and a Full Member of the Chartered Institute of Ecology and Environmental Management (CIEEM), specialising in ornithology. He has extensive experience in bird surveys and broader ecological work, including BNG assessments, EPS licences, and bat roost inspections. Outside of work, he’s a passionate birdwatcher, photographer, Master Scuba Diver, and keen cricketer.

How did you foster buy-in within your team for Coreo?

It’s a really personal thing – the key is knowing your colleagues. Particularly, it is important to know who is likely to need extra time to get to grips with the platform versus who is a natural technical whizz who is likely to get to grips with the new technology quickly. It’s also crucial to keep an eye on people as they climb the learning curve and be available to provide assistance where it’s needed. Regular check-ins are a good idea, especially because they allow for common mistakes and difficulties to be identified. Another potentially useful idea is to send people out in pairs during field surveys so that they can assist each other with the new tool.

In your experience, is a technical background required to use Coreo?

Not at all. I had very little technical background in GIS, coding or anything like that, and yet I found using Coreo very intuitive. There is of course a learning curve, but the Coreo team have made climbing it as easy and straightforward as possible, and there is ample guidance and help available if you do hit obstacles or difficulties. If you don’t have a technical background – don’t panic!

What device do you tend to use for Coreo in the field?

Personally, I use a tablet and a stylus as the large screen makes it much easier to be precise when doing drawings and entering data. I have also used a mobile phone and would say using Coreo is still feasible on the smaller screen.

What are your recommendations for sharing outputs from Coreo?

One really nice feature within Coreo is that you can share ‘guest access’ to the platform via providing a link to clients. This gives clients the opportunity to view the full body of data within Coreo in addition to the statutory metric outputs.

Useful links

Event partners

This blog was produced by the Biological Recording Company in partnership with Coreo by Natural Apptitude.

More for environmental professionals

Check out our events on Eventbrite

Networking Nutrients: Nutrients as a Driver of Invertebrate Interactions

Nutrients are one of the most fundamental drivers of interactions between species. How nutrients drive foraging by invertebrates in nature has traditionally been difficult to study, but modern methods pave the way for an enhanced understanding of invertebrate nutritional dynamics. Jordan will describe how we can study the influence of nutrients on foraging, the structure of interactions across whole ecosystems and the implications for ecosystem services like biocontrol of crop pests.

Q&A with Jordan Cuff

Jordan Cuff is a research fellow based in Newcastle University and leads the Foraging Ecology Research Group. Jordan’s research uses molecular methods to study the interactions between invertebrates and the factors that drive and constrain those interactions.

Is there a relationship between habitat complexity at a small scale, like in gardens, and the complexity of networks?

Yes, absolutely. Generally speaking, habitat heterogeneity is key. So, it’s not just having loads of long grass or loads of short grass, but a mixture of habitat structures, with different habitat types and plant species. In other words, having lots of options for different invertebrates is key.

Do you think it is possible to extend these networks to look at soil nutrient availability and start to look at how soil invertebrates are interacting with above-ground networks?

There is a really interesting dynamic between above ground and below ground systems which is vital for ecosystem health. One of my PhD students, Will Dawson, is working on soil trophic networks, not necessarily looking at the nutrient content of the invertebrates, but looking at fertiliser inputs and how that’s likely to influence the structure of those networks. We’re hoping to find some interesting results on this in the next couple of years.

What are the broader implications of this research? What do you see this research being used for?

My main interest is the fundamental science of knowing what drives invertebrate foraging, behaviour and ecology, and understanding how these systems work. Applying our understanding of these systems to agriculture and wider ecosystem services might be beneficial for people, though, by helping us to understand and manage these services and benefits. Also, understanding how our ecosystems are structured by and depend on nutrients is key to conservation, particularly now with the increasing pressures on our insect populations and subsequent biodiversity loss.

Literature References

  1. Michalko et al. (2019) Global patterns in the biocontrol efficacy of spiders: A meta-analysis: https://doi.org/10.1111/geb.12927
  2. Symondson et al. (2002) Can Generalist Predators be Effective Biocontrol Agents?: https://doi.org/10.1146/annurev.ento.47.091201.145240
  3. Mayntz et al. (2005) Nutrient-Specific Foraging in Invertebrate Predators: https://doi.org/10.1126/science.1105493
  4. Cuff et al. (2022) Density-independent prey choice, taxonomy, life history, and web characteristics determine the diet and biocontrol potential of spiders (Linyphiidae and Lycosidae) in cereal crops: https://doi.org/10.1002/edn3.272
  5. Cuff et al. (2024) Sources of prey availability data alter interpretation of outputs from prey choice null networks: https://doi.org/10.1111/een.13315
  6. Cuff et al. (2021) MEDI: Macronutrient Extraction and Determination from invertebrates, a rapid, cheap and streamlined protocol: https://doi.org/10.1111/2041-210X.13551 
  7. Cuff et al. (2025) Prey nutrient content is associated with the trophic interactions of spiders and their prey selection under field conditions: https://doi.org/10.1111/oik.10712
  8. Cuff et al. (2024) Networking nutrients: How nutrition determines the structure of ecological networks: https://doi.org/10.1111/1365-2656.14124
  9. South et al. (2025) Aquatic biological invasions exacerbate nutritional and health inequities: https://doi.org/10.1016/j.tree.2025.06.007
  10. Timberlake et al. (2022) A network approach for managing ecosystem services and improving food and nutrition security on smallholder farms: https://besjournals.onlinelibrary.wiley.com/doi/pdf/10.1002/pan3.10295
  11. Senior et al. (2016) Social Network Analysis and Nutritional Behavior: An Integrated Modeling Approach: https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2016.00018/full

Further Info

entoLIVE

entoLIVE webinars feature guest invertebrate researchers delving into their own invertebrate research. All events are free to attend and are suitable for adults of all abilities – a passion for invertebrates is all that’s required!

entoLIVE is delivered by the Biological Recording Company in partnership with the British Entomological & Natural History Society, Royal Entomological Society and Amateur Entomologists’ Society, with support from Buglife, Field Studies Council and National Biodiversity Network Trust.

The entoLIVE programme is delivered by Biological Recording Company and receives sponsorship from the following organisations:

Learn more about British wildlife

Check out our events on Eventbrite

Mesophotic Coral Ecosystems: Reefs From the Twilight Zone

Mesophotic coral ecosystems, found roughly between 30m and 150m deep in tropical and subtropical areas, still remain poorly known. They’ve nonetheless been seen to be diverse and unique, harbouring numerous species; but are already threatened by climate change. This presentation will dive into the mysteries these ecosystems hold, including the tools being used to study them in the Chagos Archipelago, Indian Ocean.

This work was undertaken by Dr Clara Diaz with Dr Nicola Foster, Dr Phil Hosegood, Prof Kerry Howell, Dr Edward Robinson, Mr Peter Ganderton and Mr Adam Bolton from the University of Plymouth

Q&A with Dr Clara Diaz

Dr Clara Diaz is a post-doctoral research fellow at the University of Plymouth investigating the ecology and resilience of mesophotic coral ecosystems

How can a reef be measured in dollars?

An ecosystem’s worth is measured by attributing economic services. For instance, coral reefs are very good at sheltering islands and coasts against waves and so it’s like an insurance that protects coasts from damage. Reefs also draw a lot of tourists, with diving activities especially. Another example is the profit from the fisheries, as the reef provides habitat and food for these commercially important fishes. An estimation of all these profits and costs are made to calculate the ecosystem service an ecosystem provides to humans.

Why do you think the corals recovered after the bleaching event?

This mass bleaching event we saw was due to the extreme deepening of the thermocline – the separation between cold and warm waters from a seasonal current. So the warm water, which is on top and in shallower waters, went very deep and stressed the coral (it was 29 degrees celsius at 100m deep!), causing this bleaching event, where the zooxanthellae (algae) were expelled from the corals. Fortunately, this warming event did not last for critically long, with the conditions coming back to normal afterwards, so the algae that had been released during the bleaching event came back to the coral. Some of the coral died unfortunately, but many survived. We were really pleased to see some of the coral recover and that they could recover after a bleaching event – if the conditions come back to normal quickly enough, corals can recover.

Have mesophotic corals’ diversity and resilience been studied in other tropical regions and if so how similar is it to the results you’ve had in the Chagos?

There are now quite a few people studying mesophotic reefs around the world, such as in the Caribbean and in the Pacific Ocean, but just not at the same scale as shallow reefs. There are a lot of similarities between the Pacific mesophotic reefs and the Indian Ocean ones, but the coral reefs in the Caribbean are quite different, i.e. with different species.

What is the one thing that we could all do, as individuals, to reduce the stress on mesophotic reefs?

One way you can help is, if eat fish, to look at how it has been fished. So, for instance, trawling destroys the habitat far more as compared to hook and line fishing. Also being aware and spreading awareness. This is an environment that is fragile, and which is very important to us and the Earth.

Literature References

  1. Diaz et al. (2025) Predicting the distribution of mesophotic coral ecosystems in the Chagos Archipelago: https://onlinelibrary.wiley.com/doi/pdf/10.1002/ece3.71130 
  2. Diaz et al. (2024) Diverse and ecologically unique mesophotic coral ecosystems in the central Indian Ocean: https://link.springer.com/content/pdf/10.1007/s00338-024-02535-3.pdf 
  3. Radice et al. (2024) Recent trends and biases in mesophotic ecosystem research: https://royalsocietypublishing.org/doi/pdf/10.1098/rsbl.2024.0465 
  4. Diaz (2023) Investigating the diversity and distribution of Mesophotic Coral Ecosystems in the Chagos Archipelago: https://pearl.plymouth.ac.uk/bms-theses/446/
  5. Diaz et al. (2023) Mesophotic coral bleaching associated with changes in thermocline depth: https://www.nature.com/articles/s41467-023-42279-2.pdf
  6. Diaz et al. (2023) Light and temperature drive the distribution of mesophotic benthic communities in the Central Indian Ocean: https://onlinelibrary.wiley.com/doi/pdfdirect/10.1111/ddi.13777 
  7. Rocha et al. (2018) Mesophotic coral ecosystems are threatened and ecologically distinct from shallow water reefs https://www.science.org/doi/10.1126/science.aaq1614

Further Info

marineLIVE

marineLIVE webinars feature guest marine biologists talking about their research into the various organisms that inhabit our seas and oceans, and the threats that they face. All events are free to attend and are suitable for adults of all abilities – a passion for marine life is all that’s required!

marineLIVE is delivered by the Biological Recording Company with funding from the British Ecological Society.

More on marine biology

Check out upcoming events on Eventbrite

British Springtails: How Many Species Really Are There?

Springtails – small invertebrates closely related to insects – are everywhere: in the soil, up trees, in rockpools, and even being blown around thousands of feet up in the air. They can reach densities of thousands per cubic metre of substrate, yet we know disproportionately little about them. We have a poor grasp on even the most basic level of information: which, and how many, species we have in the UK. James will put forward the case that we may be underestimating the diversity of springtails we have in the UK, and explain how we can resolve this using various sources of data, from citizen science to whole genome sequences. He will also delve into how getting a firm grasp of springtail diversity, as well as understanding how this diversity has come to be, has implications for evolutionary biology, ecology, invasion biology, and conservation.

Q&A with James McCulloch

James McCulloch is the National Recorder for springtails (Collembola), and a PhD student in the evolutionary genomics of springtails at the Wellcome Sanger Institute and the University of Cambridge.

What do you see as the main barriers in terms of recruiting people into recording springtails?

I think that the FSC springtail AIDGAP key published in 2007 was really useful for people with microscopes to identify springtails. However, beginners who purchase this key as a starting point to identify springtails could find it quite difficult because a lot of their features do rely on microscopy. But a lot of springtails can be identified from record photos. Creating a resource that is focused more on identification through photos as opposed to microscopy would be a good way to encourage new recorders.

What is the practical impact of these cryptic species on springtail recording?

When we realised how much cryptic diversity there might be in springtails, we wondered how we were going to keep track of them. A lot of people don’t have access to genetic sequencing facilities, and it could make getting into springtail recording very difficult or off-putting for new people. I think that it is still useful to record springtails that are different morphologically as morphospecies. That way we can still get a lot of data while acknowledging that they may not be species in the strict genetic sense; these data will still be useful given that cryptic species are likely to be similar ecologically.

Do you need fresh specimens for genome sequencing?

Ideally the specimens should be alive until they go into the lab. They are then flash frozen at -70 degrees. This prevents the DNA from breaking down into smaller chunks and we can get longer reads that are much easier to piece together into a genome. Short-read genome sequences can be used for population genomic analysis, which can tell us about population movements and gene flow, for example, and these can be assembled from dead specimens stored in high concentration ethanol for a short time. These are most useful when there is already a high-quality long-read reference genome for that species or a closely-related species, though the pace of methodological advancements will make it easier to assemble good reference genomes from dead specimens in the near future.

Has there been any progress in using eDNA in the study of springtails?

I am not aware of any eDNA work on springtails specifically. Since springtails occur at such high densities in soil, it isn’t totally unreasonable to consider studying them from an eDNA perspective. However, we don’t have a comprehensive DNA database for springtails yet so we wouldn’t be able to confidently identify a lot of the genetic sequences that we would see in the eDNA samples.

Literature References

  1. McCullock (2025) Entomobrya petri sp. nov.: A new species of springtail found in the British Isles: https://doi.org/10.25674/476
  2. Hutchinson and McCulloch (2024) Fasciosminthurus quinquefasciatus (Symphypleona: Bourletiellidae), New to Britain: https://www.researchgate.net/publication/379733637_Fasciosminthurus_quinquefasciatus_Symphypleona_Bourletiellidae_New_to_Britain
  3. Du et al. (2024) Revisiting the four Hexapoda classes: Protura as the sister group to all other hexapods: https://www.pnas.org/doi/10.1073/pnas.2408775121
  4. Chen et al. (2019) Structure and functions of the ventral tube of the clover springtail Sminthurus viridis (Collembola: Sminthuridae): https://www.researchgate.net/publication/330711582_Structure_and_functions_of_the_ventral_tube_of_the_clover_springtail_Sminthurus_viridis_Collembola_Sminthuridae
  5. Yu et al. (2014) Whole-genome-based phylogenetic analyses provide new insights into the evolution of springtails (Hexapoda: Collembola): https://www.sciencedirect.com/science/article/abs/pii/S1055790324001611
  6. Whalley and Jarzembowski (1981) A new assessment of Rhyniella, the earliest known insect, from the Devonian of Rhynie, Scotland: https://www.nature.com/articles/291317a0
  7. Potapov et al. (2023) Globally invariant metabolism but density-diversity mismatch in springtails: https://www.nature.com/articles/s41467-023-36216-6
  8. Hensel et al. (2013) Tunable nano-replication to explore the omniphobic characteristics of springtail skin: https://www.researchgate.net/publication/245540698_Tunable_nano-replication_to_explore_the_omniphobic_characteristics_of_springtail_skin
  9. Lukić et al. (2018) Setting a morphological framework for the genus Verhoeffiella (Collembola, Entomobryidae) for describing new troglomorphic species from the Dinaric karst (Western Balkans): https://www.researchgate.net/publication/328285277_Setting_a_morphological_framework_for_the_genus_Verhoeffiella_Collembola_Entomobryidae_for_describing_new_troglomorphic_species_from_the_Dinaric_karst_Western_Balkans
  10. Lukić et al. (2019) Distribution pattern and radiation of the European subterranean genus Verhoeffiella (Collembola, Entomobryidae): https://onlinelibrary.wiley.com/doi/abs/10.1111/zsc.12392
  11. Dukes et al. (2022) Specific and intraspecific diversity of Symphypleona and Neelipleona (Hexapoda: Collembola) in southern High Appalachia (USA): https://www.researchgate.net/publication/364257425_Specific_and_Intraspecific_Diversity_of_Symphypleona_and_Neelipleona_Hexapoda_Collembola_in_Southern_High_Appalachia_USA
  12. Zhang et al. (2025) Diversification of alpine soil animals corroborates uplifts and environmental changes of Qinghai-Tibetan Plateau and Himalayas: Insights from molecular phylogeny and cryptic diversity of the Isotoma quadridentata Complex (Collembola: Isotomidae): https://onlinelibrary.wiley.com/doi/10.1111/zsc.70004?af=R
  13. Martin et al. (2019) Recombination rate variation shapes barriers to introgression across butterfly genomes: https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2006288
  14. Chernova et al. (2009) Ecological significance of parthenogenesis in Collembola: https://link.springer.com/article/10.1134/S0013873810010033
  15. Riparbelli et al. (2006): Centrosome inheritance in the parthenogenetic egg of the collembolan Folsomia candida: https://pubmed.ncbi.nlm.nih.gov/16906420/
  16. Hart et al. (2025) Genomic divergence across the tree of life: https://www.pnas.org/doi/10.1073/pnas.2319389122

Further Info

entoLIVE

entoLIVE webinars feature guest invertebrate researchers delving into their own invertebrate research. All events are free to attend and are suitable for adults of all abilities – a passion for invertebrates is all that’s required!

entoLIVE is delivered by the Biological Recording Company in partnership with the British Entomological & Natural History Society, Royal Entomological Society and Amateur Entomologists’ Society, with support from Buglife, Field Studies Council and National Biodiversity Network Trust.

The entoLIVE programme is delivered by Biological Recording Company and receives sponsorship from the following organisations:

Learn more about British wildlife

Check out our events on Eventbrite

AI-powered Bioacoustics with BirdNET

How can computers learn to recognise birds from sounds? The Cornell Lab of Ornithology and the Chemnitz University of Technology are trying to find an answer to this question.

Their research has led to the development and evolution of BirdNET – an artificial neural network that has learned to detect and classify avian sounds through machine learning.

This webinar provides an introduction to BirdNET, how it works and and how the use of BirdNET can be scaled to generate huge biodiversity datasets (with a case study from Wilder Sensing).

BirdNET: Advancing Conservation with AI-Powered Sound ID

Dr Stefan Kahl (Cornell Lab of Ornithology and Chemnitz University)

Learn about how BirdNET was built with Dr Stefan Kahl. He’ll cover some basics about AI for sound ID, present a few case studies that have used BirdNET at scale and then conclude with some thoughts on the future of AI in bioacoustics.

Dr Stefan Kahl is a computer science post-doc at the Cornell Lab of Ornithology and Chemnitz University in Germany, working on AI algorithms for animal sound ID. He is lead of the BirdNET team, where they develop state-of-the-art tools for anyone interested in large-scale acoustic monitoring.

How did you handle species with multiple distinct call types?

We put all of the files from one species into a folder and told the AI model that this is one species. That has worked relatively well, these models are able to distinguish different call types for the same species so we can do calls, we can do songs, we can do all kinds of call types. We know that these feature vectors embed these call types, and we can re-construct it. So, after you’ve run BirdNET, instead of the class scores if you take these embeddings, you can do a clustering and cluster out these different call types and you’ll end up with a nice visualisation.

Sometimes what people will do, if they are interested in something specific like mating calls, you can train a custom classifier, as long as it is a category. So, if you can categorise it, it can become a model. So, if you want to run a call type model instead of a species model you can. One category of call types which is challenging is flight calls. Not all of the species have sufficient flight call data and flight calls tend to be short. I would exclude those.

How did you settle on the three second segments for the sampling?

We wanted to reduce the input size as these models are computationally expensive. So, the bigger the input, the more computationally expensive, so we want the smallest spectrogram you can have that still retains all the detail.

During my PhD, I did an empirical study looking at the average bird song length and the literature gave a time of two seconds. I added half a second before and after to have some wiggle room and that’s why we chose three seconds. We know some people are using five seconds and that is usually fine if you have longer context windows that might help with call sequences. Sometimes three seconds is not good enough as you need a temporal component to it.

Do recordings need to be added to Xeno-canto or can you access recordings from Merlin and other systems?

Merlin doesn’t currently leverage user’s observations, i.e., Merlin is not collecting data that we can use. We have access to recording submitted to eBird and Macaulay Library, though Xeno-Canto is a bit faster to allow non-bird uploads. The best The best way for users of BirdNET-Pi is BirdWeather (get a device ID and hook it up to the BirdWeather platform).

Is there a way to reduce the number of false positives in BirdNET?

Yes, you can also use false positives to train a custom classifier and then BirdNET will (hopefully) learn to separate target from non-target sounds. So basically, using those “negative” samples to train a model.

What is needed to scale BirdNET fast?

More data. Plus anecdotal evidence on how people are using it, so we can learn what we need to tackle to make it more useful.

Do you know if anyone is using BirdNET to look at the relationship between anthropogenic noise and species abundance?

Not abundance but disturbance – there’s a project going on in Yellowstone National Park looking at the impact of snowmobiles on bird vocalisation. They found that engine sounds are a significant disturbance and needs to be managed, i.e., birds will stop vocalizing for extended periods of time, even well after the snowmobiles have passed.

What data augmentation techniques do you use (if any) to expand your training dataset?

MixUp (mixing multi recordings into one) is the most important and most effective augmentation. We had a student look into augmentations a while ago.

A Scalable Platform for Ecological Monitoring

Lorenzo Trojan (Wilder Sensing)

How can we measure the impact of wildlife restoration, assess biodiversity loss, and evaluate the effectiveness of environmental policies? Passive bioacoustic monitoring offers a powerful solution, enabling continuous, large-scale coverage of ecosystems. To fully harness its potential, we need a scalable, robust software platform capable of handling vast audio datasets, detecting key biological sounds using AI, and extracting ecological insights such as species richness and assemblage trends.

This presentation explores the challenges of biodiversity monitoring with passive audio recorders, the processing and analysis of large-scale acoustic data, and the technologies that make this approach viable and impactful. We’ll also showcase how the Wilder Sensing Platform is purpose-built to meet these demands—providing researchers, conservationists, and policymakers with an intuitive, scalable, and efficient tool for biodiversity monitoring and ecological surveys.

Dr Lorenzo Trojan is a technologist with a PhD in Astrophysics and over a decade of leadership experience in high-growth tech startups. His expertise spans remote sensing, cloud computing, DevOps, and AI. As CTO of Wilder Sensing, he leads the development of a scalable platform for ecological monitoring, driven by a commitment to innovation, inclusivity, and impact.

What is the trade-off between sample rate and bits per sample and the accuracy of detection as a method for reducing storage requirements?

From a series of preliminary experiments we conducted using recordings encoded at different sampling rates, we did not find a substantial drop in the quality or quantity of detections obtained from BirdNET.

These results are preliminary and based on a limited dataset; however, they provide a clear indication that reducing sampling rate can be an acceptable approach to mitigating data volume and storage costs with little or negligible impact on detection quality.

The Wilder Sensing monitoring guidelines are therefore based on these findings, adopting a configuration that represents a practical compromise between detection performance and data volume.

What are the main features within the Wilder Sensing platform that make BirdNET more accessible for people with boots on the ground?

Our platform enables anyone requiring biodiversity monitoring of large estates to streamline the process of collecting, storing, retrieving and analysing the large volumes of data associated with passive bioacoustics, providing a simple and accessible way to understand what species are present within a landscape.

Audio files are collected and organised into projects and linked to individual recording devices, with metadata such as recording time and geolocation automatically associated with each recording. The recordings are automatically processed using BirdNET, and the resulting detections are presented through simple and accessible analytics dashboards that allow users to explore species activity across locations and time periods. Audio files can also be optionally stored in long-term archives for auditing and verification purposes.

How affordable is large-scale bioacoustics monitoring for organisations with limited funding?

Passive acoustic monitoring is one of the most cost-effective approaches to biodiversity monitoring. It enables large estates and diverse ecosystems to be monitored continuously over extended periods using relatively inexpensive recording devices and minimal field manpower. This makes it particularly well suited to organisations with limited monitoring budgets, such as NGOs, academic institutions and conservation groups.

Wilder Sensing further reduces the operational complexity associated with large-scale bioacoustic monitoring by providing a platform for storing, organising and analysing the large volumes of audio data generated by these deployments. The platform allows users to perform automated BirdNET analysis, explore results through intuitive analytics tools, and share datasets and findings without needing to manage specialised infrastructure or data pipelines.

As part of our mission to support scientific understanding of the environment, Wilder Sensing offers pricing structures designed to remain accessible to research and conservation organisations.

What are the costs outside of Wilder Sensing that not-for-profits need to consider in their budget? 

Outside of the Wilder Sensing platform itself, the main costs associated with a bioacoustic monitoring project typically relate to field equipment and operational logistics. These include the purchase of recording devices, memory cards, and accessories required for deployment such as protective enclosures, mounting hardware or fencing where necessary.

Field operations also represent an important component of the overall budget. Organisations need to consider the staff time required for deploying devices, visiting monitoring sites to replace batteries and SD cards, and retrieving equipment at the end of the monitoring period. Additional ongoing costs may include replacement batteries, maintenance of devices, and the occasional replacement of damaged or lost equipment.

The relative importance of these costs can vary considerably depending on the nature of the monitoring project. Factors such as project duration, site accessibility, ecological objectives and the availability of trained staff or volunteers can significantly influence the total operational cost.

A long-term monitoring project lasting several months or years may require regular site visits to replace batteries and memory cards. If monitoring locations are difficult to access or require specific safety procedures or permissions (wetlands, railway corridors, renewable energy installations) additional logistical planning may be required.

In contrast, shorter projects targeting specific species during limited periods (for example, during breeding or nesting seasons) may require fewer devices, fewer site visits and lower operational costs overall.

In some cases, Wilder Sensing may also be able to support projects through bespoke monitoring arrangements. While this is not part of our standard service offering, we have occasionally worked with organisations—particularly academic institutions—to provide tailored monitoring packages where recording equipment is temporarily loaned as part of the project. These arrangements are considered on a case-by-case basis and are intended to help facilitate research or conservation initiatives where budget constraints might otherwise limit the feasibility of large-scale monitoring.

Useful links

Wilder Sensing ecoTECH blogs

  1. How Can We Use Sound to Measure Biodiversity: https://biologicalrecording.co.uk/2024/07/09/bioacoustics-1/
  2. Can Passive Acoustic Monitoring of Birds Replace Site Surveys blog: https://biologicalrecording.co.uk/2024/09/17/bioacoustics-2/
  3. The Wilder Sensing Guide to Mastering Bioacoustic Bird Surveys: https://biologicalrecording.co.uk/2024/11/26/bioacoustics-3/
  4. Bioacoustics for Regenerative Agriculture: https://biologicalrecording.co.uk/2025/03/31/bioacoustics-for-regen-ag/
  5. AI-powered Bioacoustics with BirdNET: https://biologicalrecording.co.uk/2025/07/08/birdnet/
  6. Making the Most of Bird Sounds: https://biologicalrecording.co.uk/2026/03/11/making-the-most-of-bird-sounds/

Event partners

This blog was produced by the Biological Recording Company in partnership with Wilder Sensing, Wildlife Acoustics and NHBS.

More for environmental professionals

Check out our events on Eventbrite

Community Voice Method: Engaging Local Communities in Turtle Conservation

Hear about how the documentary film-based Community Voice Method (CVM) has been used to engage Caribbean Island communities in developing marine turtle conservation policy. The methodology will be discussed along with experiences of its applications in various communities across the Caribbean UK Overseas Territories. We’ll explore the challenges and opportunities of using this method, and provide case studies on the application of CVM in supporting population recovery.

Q&A with Amdeep Sanghera

Amdeep Sanghera is the UK Overseas Territories Conservation Manager at the Marine Conservation Society. He is a trained social scientist with experience in marine turtle conservation, tropical fisheries research and community-based conservation. Amdeep initially joined MCS in 2008 as the Turks and Caicos Islands Turtle Project Officer, and was based out in the Caribbean, helping to deliver conservation measures for the island’s marine turtle populations. As part of a team, Amdeep enabled the island’s fishing communities to shape these laws through the Community Voice Method (CVM) documentary film tool. Building on this, Amdeep is now focusing on the Caribbean UK Overseas Territories, employing the CVM as part of partnership projects to work with communities to improve the management of turtle populations.

How were the participants chosen for the consultations and workshops?

Because we wanted to develop resilient solutions that reflected community values, the workshops were open to everyone. This wasn’t just about just turtle conservation and so we wanted to nestle this within the wider issues that were happening on these islands. By having wider participation, we could get solutions that would be more widely accepted. We did, however, target some groups, like the fishing community and local conservationists, to make sure that their voices were heard.

Why was the Community Voice Method used?

We’d heard about this method through academic research and that it had some very good results. We spoke to the stakeholders about it and they were very keen to try it. It worked really well because not only did the fishermen that I spoke to feel that they had a voice, it also helped to bring a lot of trust. Now that the territory partners are seeing the results, they want training in this method.

Has the Community Voice Method had a direct impact on protecting turtles and turtle conservation?

Community Voice Method is a long-term process for developing trust with communities and looking to work with them to create conservation solutions. Community Voice Method has given the communities a voice, a platform, and really does empower them. We’ve been going back to the Turks and Caicos to speak to the fishermen and they’ve been telling us that they’re no longer catching the large turtles, that they understand that they are the breeders and should be protected. We can triangulate that with community perceptions and the fact that compliance has really risen. And we are now seeing turtle nesting happen in places where the project has never detected it before. We think the nesting turtle population could be in the early stages of recovery, and I think this is due to fishers and enforcement officers working with the new laws. I think CVM has had a significant role in bringing about this shift, and resulting turtle conservation.

Literature References

  1. Cumming et al. (2021) Putting stakeholder engagement in its place: How situating public participation in community improves natural resource management outcomes: https://link.springer.com/article/10.1007/s10708-020-10367-1

Further Info

marineLIVE

marineLIVE webinars feature guest marine biologists talking about their research into the various organisms that inhabit our seas and oceans, and the threats that they face. All events are free to attend and are suitable for adults of all abilities – a passion for marine life is all that’s required!

marineLIVE is delivered by the Biological Recording Company with funding from the British Ecological Society.

More on marine biology

Check out upcoming events on Eventbrite