Cave Spiders: Behavioural Adaptations in Webs, Foraging and Dispersal

Web-building spiders are excellent model organisms to study the behavioural adaptations to novel habitats such as the dark and food-limited subterranean cave habitat. Cave-dwelling orb spiders in the genus Meta show several potential behavioural adaptations in both their webs (which do not have the typical frame of non-cave orb spiders) and their foraging and dispersal behaviour. Thomas will explore some of the things we do know about these fascinating spiders as well as discuss some of the many things we still do not know.

Q&A with Dr Thomas Hesselberg

Dr Thomas Hesselberg is a lecturer at the Oxford University Department for Continuing Education where he directs the department’s online PgCert in Ecological Survey Techniques. His research is on the behavioural ecology of insects and spiders with a focus on web-building behaviour in orb spiders. Recently he has developed an interest in how spiders adapt their webs to different habitats including to islands, cities and caves.

  1. How is a lack of pigment connected to a lack of light?
    The theory is that a lack of pigment is due to the species not needing to be colourful in a dark environment, and this is the same for loss of eyes in cave organisms. One hypothesis is that this is due to neutral selection, i.e. they are not needed so they will slowly disappear over generations. An alternative hypothesis, which I favour, is that production of pigment has a cost and loss of pigment is actively selected against to conserve resources. 
  2. What is the biggest cave orb web spider?
    Meta menardi that we have in the UK is one of the biggest Meta species that we know of. They are relatively large compared to most species of spiders found in the UK, and just a little smaller than the largest species of house spider and the fen raft spider.
  3. Have you noticed changes to cave spiders or cave environments during your time researching cave spiders?
    There are some really interesting examples of caves being impacted by climate change. Changes are likely to be delayed in comparison to above-ground environments as caves are isolated from external environments to some degree. However, the average temperature of a cave will be linked to the average temperature outside the cave so over time changes will occur and there is likely to be an impact. I’ve only been studying cave spiders since 2018 so it is not something that I’ve personally observed within my research, but cave spiders seem to be doing ok within the UK and we’re not aware of the same declines that we are seeing in other invertebrate groups. However, we have relatively limited data for cave spiders and we’re not yet even at the point where we can assign accurate conservation statuses to them in the UK or elsewhere.
  4. Does the inclination (how vertically-orientated they are) of the webs differ in caves?
    That’s a very interesting question. We have looked at this to see if there are differences as you get further into the cave and the hunting method changes. We’ve not observed any differences, but we need to look more closely at winter versus summer webs as the numbers of crawling prey show seasonal differences. Watch this space!
  5. Do you use a specific frequency when using tuning forks to stimulate the spider’s prey capture response?
    We typically use 128 hertz to simulate a larger prey and 440 hertz to stimulate smaller prey to try and match the wingbeat frequency of prey as they attempt to free themselves from the web. However, our cave spiders to seem to react to almost all frequencies. In aboveground spiders, we have found that they are more likely to attack with higher frequencies and more hesitant with lower frequencies which would indicate a larger and more risky prey.
  6. How should we report records of cave spiders?
    We use records from the British Arachnological Society to look at the distributions of species and what habitats they are being found within. If you are interested in recording cave spiders (or any species of spider), it is worth checking out the Spider Recording Scheme website for guidance on how to record spiders and submit your records.

Literature References

  1. Barrentes & Eberhard (2012) Extreme behavioral adjustments by an orb-web spider to restricted space: https://doi.org/10.1111/j.1439-0310.2012.02029.x
  2. Buchli (1969) Hunting behaviour in the Ctenizidae: https://doi.org/10.1093/icb/9.1.175
  3. Culver & Pipan (2009) The Biology of Caves and Other Subterranean Habitats: https://academic.oup.com/book/34995
  4. Hesselberg et al (2019)  Do cave orb spiders show unique behavioural adaptations to subterranean life? A review of the evidence: https://brill.com/view/journals/beh/156/10/article-p969_1.xml?language=en
  5. Howarth & Moldovan (2018) The ecological classification of cave animals and their adaptations: https://link.springer.com/chapter/10.1007/978-3-319-98852-8_4
  6. Lunghi et al (2024) Behavioural adjustments enable the colonization of subterranean environments: https://doi.org/10.1093/zoolinnean/zlad133
  7. Mammola (2019) Finding answers in the dark: Caves as models in ecology fifty years after Poulson and White: https://nsojournals.onlinelibrary.wiley.com/doi/abs/10.1111/ecog.03905
  8. Mammola & Isaia (2014) Niche differentiation in Meta bourneti and M. menardi (Aranea,Tetragnathidae) with notes on the life history: https://digitalcommons.usf.edu/ijs/vol43/iss3/11/
  9. Simonsen & Hesselberg (2021) Unique behavioural modifications in the web structure of the cave orb spider Meta menardi (Aranaea, Tetragnathidae): https://www.nature.com/articles/s41598-020-79868-w
  10. Smithers (2005)The early life history and dispersal of the cave spider Meta menardi Latreille,1804)(Araneae:Tetragnathidae): https://britishspiders.org.uk/system/files/library/130605.pdf
  11. Tew & Hesselberg (2017) The effect of wind exposure on the web characteristics of a tetragnathid orb spider: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5488162/

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.

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Earthworm Image Recognition Project

Identifying British earthworms currently requires collecting and killing specimens, to then use microscopic morphological features for identification. This is the biggest barrier to earthworm recording and limits the number of people who are willing and able to contribute earthworm species occurrence data to the National Earthworm Recording Scheme.

So, what if there was a way to identify earthworms live? So far, no live earthworm ID guide has proven accurate enough to meet the high standards of the National Earthworm Recording Scheme. This isn’t necessarily because some earthworm species couldn’t be identified live, but more likely because we simply don’t have enough data on the natural variation in live ID characters within and between species to produce a reliable guide.

The Earthworm Image Recognition Project was established to investigate the possibility of using auto-identification of earthworms from photos for use in future soil health apps.

This project received funding from the Department for Environment, Food and Rural Affairs (Defra) as part of the Natural Capital and Ecosystem Assessment (NCEA) programme. The NCEA is undertaking a nationwide survey of England’s land, coast and sea with the aim of transforming environmental decision-making by building a ‘whole system’ picture of the state of our natural environment

NCEA_logos_CMYK

This proof-of-concept study was delivered by the UK Centre for Ecology and Hydrology and Biological Recording Company with guidance from the Earthworm Society of Britain, Defra and the Joint Nature Conservation Committee.

Earthworm Sampling Days

A programme of 16 Earthworm Sampling Days was delivered at sites across England and Wales. During these events, participants sampled for earthworms and used their personal smartphone devices to take photos of the specimens using a specific protocol. Following photography of the earthworms, the specimens were collected, euthanised and preserved so that they could be accurately identified by the National Recorder for Earthworms. Photos were submitted by the volunteer earthworm surveyors following the event and then added to the earthworm image training library.

No experience was necessary as all participants were trained on both earthworm sampling and the smartphone photography protocol. Furthermore, no photography skills were required – it’s important that the images used to train the AI come from a range of devices and are taken by individuals ranging in smartphone photography skill level so that the training data represents the actual data that farmers would be submitting when the app is tested.

Tees-Swale Naturally Connect volunteers photographing earthworms for the Earthworm Image Recognition Project in 2023

In addition to the primary of aim of generating a training image library, the Earthworm Sampling Day programme also benefited the National Earthworm Recording Scheme by generating 295 new species occurrence records, including 11 instances where species were recorded for the first time within a Watsonian vice county. It also engaged new people with earthworm recording, resulted in specimens being added to regional and national museum collections and

Summary of biological recording achievements resulting from the Earthworm Sampling Day programme.

Developing the Algorithm

In addition to the Earthworm Sampling Days, earthworms were collected, photographed and identified by Keiron Brown and Aidan Keith. A total of 12,179 photographs were taken of 650 different earthworm specimens that were identified to species level. 21 out of 30 UK species (or species aggregates) were represented within the training image library.

Summary of Earthworm Impage Recognition Project achievements to date

The images were divided into training, validation and testing sets and the algorithm underwent 34 epochs (training steps) until it no longer showed signs of improvement, reaching an overall accuracy of 42%. The confusion matrix below illustrates how the accuracy of the algorithm to correctly identify individual species was significantly variable and ranged from 0% to 69% depending on the species. A perfect algorithm would display a strong diagonal band and significant values away from this diagonal band indicate common misclassification. Looking at the significant misclassifications helped us to recommend a number of improvements to the image collection protocol and algorithm development that can be implemented to improve the performance of the model.

Confusion matrix for algorithm of earthworm classifications. Colour indicates the number of images in the test dataset.

We also established issues with the algorithm using the whole image (rather than just the area with the earthworm) for species classification and recommendations were made for reducing or eliminating this issue.

Proof-of-concept Conclusions

  1. It is possible to recruit volunteers to collect a large number of images of earthworms using a detailed protocol.
  2. These images can be used as a training dataset by combining collection with laboratory identification.
  3. The collection protocol should be refined to avoid the over-handling of specimens, keep the collection tray clean and avoid strong shadows.
  4. The image set is strongly biased towards common species and more sampling effort will be required to balance the existing library.
  5. Using a segmentation algorithm to mask out the earthworms prior to classification may improve the performance of the algorithm.
  6. Species that bare proving too difficult for the algorithm to classify should be grouped into aggregates to improve the overall results.
  7. Computer vision models show some promise but more development is needed for a usable solution.

The Earthworm Image Recognition Project Activity Report provides a more detailed overview of this proof-of-concept study.

Earthworm Image Recognition Project Activity Report v5 25.11.24Download

Acknowledgements

We’d like to say thank you to Defra and JNCC for sitting on a steering group for the project and to all the organisations that helped us to deliver this programme of events.

We’d also like to say a huge thank you to all of the volunteers who contributed to the sampling, photography and identification of earthworm specimens.

More on earthworms

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Seahorses of the UK: Conservation and Research

Seahorses are enigmatic species, their form and mythical appearance instilling a sense of wonder for many. Their status as a symbol for the oceans is used across the world, however little awareness is given to the threats and challenges that they face, the research and work being delivered to protect them, and for the UK, their presence in our waters. Join this session to hear more about these amazing creatures, and about how you can support our marine environment.

The Seahorse Trust is offering marineLIVE attendees an exclusive discount on their Seahorse Ecology online course. This course is normally priced £65 and can be purchased for just £50 by emailing the Seahorse Trust at theseahorsetrust@gmail.com to request a place on this course and quote the code marineLIVEto claim your discount!

Q&A with Beccy MacDonald-Lofts

Beccy MacDonald-Lofts is an enthusiastic marine conservationist and educator who is passionate about connecting people and nature. Her experience is cross-sector, providing her with a broad view of the challenges and solutions that face our coastal and marine environment, and those who depend upon them. Beccy is a Trustee for MARINElife, ordinary council member for the Porcupine Marine Natural History Society, sits on the National Seahorse Working Group and has been a volunteer surveyor, and previously a trustee, for The Seahorse Trust for whom she also coordinates their online learning course.

  1. What is the usual lifespan of a seahorse?
    That depends on the species. It also depends on individuals in captivity versus in the wild. We don’t really have precise data for how long seahorses live in the wild. It is believed that for UK species it is up to 7-9 years, but we need research that tracks seahorses for their entire lives to confirm this. The difficulty with doing this in the wild is that individuals will leave an area and move around so it can be difficult to know if an individual is not in an area from year to the next because it is somewhere else or because it has died. Research into the life histories of wild seahorses has developed in recent years through the introduction of Photo Identification using the unique spot patterns of individuals, however this is still in its early application and their size limits the use of the current range of fish trackers.
  2. What water depth range are they found at?
    This varies depending on the time of year. At Studland Bay during the summer months, we find them at depths of 1 metre or less, but the tide is coming in and out during the day so this depth is also varying depending on the tide. During the winter months they are found further out in the English Channel at some quite significant depths and are sometimes caught by trawlers. Again, there’s a lot more research for us to do to understand this in more detail.
  3. What eats seahorses?
    UK seahorses range in size and can be as large as 30 cm so adults tend to be eaten by larger fish, including rays and smaller sharks.
  4. How many species of seahorse are known in the UK?
    It is only relatively recently that we established that seahorses are present year-round in the UK and breeding here. This was an important discovery and highlights how easy it is to overlook them. We have two species that occur in UK waters. The gaps in the Seahorse Trust distribution maps do not tell us that seahorses are not there, as survey effort is biased towards southern waters where more people dive. It is also possible that they are being missed in areas where they are not known as they are a cryptic species making them difficult to spot and people may well miss them as they are not expecting to see them.
  5. Do we know why flash photography is so damaging to seahorses?
    It is assumed that it is because of their eyesight. They live in a relatively darkened environment and have acute eyesight. Flashes of light are not something that is naturally occurring in these environments, so we need to be aware of how this sudden flash of light impacts the animal physically and psychologically. Research into the impacts upon the UK species is difficult as the populations are small and ethically, we need to consider whether it is appropriate to remove individuals and conduct research on them just for the purpose of using flash photography.
  6. How do you tell the difference between a male and a female seahorse?
    It is all to do with the shape of their body. The females have a protruding feature under the abdomen. This is the ovipositor. The males have an obvious hole underneath an expandable abdomen pouch, which is where the female inserts the ovipositor to insert her unfertilised eggs and where the fry exit from. The males experience a true pregnancy as the babies receive all their nutrition from the father and the pregnancy ends with contractions when giving birth!
  7. What is the one thing that we can all do to help UK seahorses?
    Just because you don’t live near the coast does not mean that you can’t be helpful. Seahorses aren’t just found in the sea… we are seeing seahorses moving into estuaries! Everyone can look at their own actions and think about what we can do to minimise their impact on our rivers and marine environments, for example, what chemicals are you pouring down the sink and making life choices that reduce our impact on the natural environment.

Literature References

  1. Lourie (2016) Seahorses A Life-Size Guide to Every Species: https://www.nhbs.com/seahorses-a-life-size-guide-to-every-species-book

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.

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Sow Wild! and Insect Identification

Habitat loss and fragmentation are considered the foremost threats in pollinator decline, and in England and Wales, 97% of wildflower meadows were lost by 1984. Gardens have considerable potential for supporting pollinators, covering large areas of urban landscapes often with diverse floral resources. Buzz Club used citizen science to investigate the effectiveness of small 4m2 sown wildflower ‘mini-meadows’ in UK gardens and allotments in recruiting beneficial insects. They then examined effective methods and any potential bias in the identification and sampling methods conducted by citizen scientists. Janine will explain the results of the ‘Sow Wild!’ project, followed by Issy who will talk about the Buzz Club’s new ‘Insect ID Quiz’ project. The insect ID Quiz is helping the Buzz Club determine if training will help to limit any identification bias in citizen science observations.

Q&A with Dr Janine Griffiths-Lee

Dr Janine Griffiths-Lee is a post-doctoral researcher at RBG Kew. Based at Wakehurst, she works in the Nature Unlocked team studying pollinators in the landscape. Her current focus is the benefits of different tree species to pollinators, habitat management in urban gardens, and citizen science.

Does the richness of wild bee species refer to the number of species or the diversity of species?

This refers to the number of species. Looking at the diversity is more complicated and looking at the significance of this was not something that we were able to look at in detail. In the paper, we do discuss the diversity but it’s quite complicated, so if you are interested in the diversity of bees that we collected I’d recommend checking out the paper.

Is it possible to get details of the wildflower mixes used in the Sow Wild! Project?

All of our mixes are listed in the appendix of the research paper. I made my own mixes for this project, but the Buzz Club also have a really successful wildflower mix as part of our sponsor packs. Its lovely and bees come throughout the year with this mix.

You can find out more about becoming a sponsor and learn about our sponsor packs here: https://www.thebuzzclub.uk/memberandsponsor

Have you considered using bioacoustics and machine learning to look at insect activity in denser patches?

We are looking into different methods of bioacoustics and how accurate the level of detail is, for example, can you get to genus or just to broad groups? It was certainly out of scope for this study because it would have been a great expense to send such equipment to citizen scientists. We had 150 participants, so we really had to be quite aware of our limitations. But it is something interesting that I am working with at the moment – bioacoustics, and camera trapping as well.

Is it possible to get details of the wildflower mixes used in the Sow Wild! Project?

All of our mixes are listed in the appendix of the research paper. I made my own mixes for this project, but the Buzz Club also have a really successful wildflower mix as part of our sponsor packs. Its lovely and bees come throughout the year with this mix.

Q&A with Isobel Sexton

Issy Sexton is a Research Assistant at the University of Sussex, specialising in pollinator-focused citizen science. She also has a background in community engagement and environmental policy.

Are there any plans to follow on from the Sow Wild project?

Isobel: The Insect ID project leads directly on from it of course, but we don’t have any other projects in the pipeline leading on from this just yet. However, we’re always expanding our programme of projects so watch this space

Are the resources from these experiments available online?

The training webinar from the project is only available to the participants currently. The quizzes and online resources are free for everyone so you can go and try the quizzes here: https://www.thebuzzclub.uk/resources We also have flash cards. I haven’t created them yet for the bee project, but for others, you can print them off and take them into your garden to practise IDing. To access the training videos you need to be signed up as a project participant.

What is the plan for Insect ID in 2025?

What I’d really like to do is analyse the results and then take it forward in terms of how the skills gained from looking at the photos online are then transferred to the field. All of this is showing that it works really well online but how well does this translate when using the skills in the field?

I’d also like to look at the training and look at how long the skills are retained. Everyone was given two weeks to complete the first quiz, then a week’s break to do the training if they were in the training-between-quizzes group, or just a week’s break if they were in the control group, then they had two weeks to do the quiz. I left it like that because it was a citizen science project and I wanted people to enjoy doing it and not feel like it was a task. However, and again, I haven’t done the statistics on this yet, but just by looking, the people who did the training and then did the quiz straight away got the highest scores. Those who left it for two weeks still improved their scores somewhat. Those who did it straight away doubled their scores and the people who left it added four or five points. So that is something interesting to look at and to develop to make sure we can retain the information.

Literature References

  1. Klein et al (2007) Importance of pollinators in changing landscapes for world crops: https://doi.org/10.1098/rspb.2006.3721
  2. Ollerton et al (2011) How many flowering plants are pollinated by animals?: https://doi.org/10.1111/j.1600-0706.2010.18644.x
  3. Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (2016) Summary for policy makers of the global assessment report of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services on pollinators, pollination, and food production: https://www.ipbes.net/assessment-reports/pollinators
  4. Baldock et al (2019) A systems approach reveals urban pollinator hotspots and conservation opportunities: https://doi.org/10.1038/s41559-018-0769-y
  5. Smith & Fellowes 2013 (2013) Towards a lawn without grass: the journey of the imperfect lawn and its analogues: https://doi.org/10.1080/14601176.2013.799314
  6. Goddard et al (2013) Why garden for wildlife? Social and ecological drivers, motivations and barriers for biodiversity management in residential landscapes: https://doi.org/10.1016/j.ecolecon.2012.07.016
  7. Balfour & Ratnieks (2022) The disproportionate value of ‘weeds’ to pollinators and biodiversity: https://doi.org/10.1111/1365-2664.14132
  8. Griffiths-Lee et al  (2022). Sown mini-meadows increase pollinator diversity in gardens: https://doi.org/10.1007/s10841-022-00387-2
  9. Bonney et al (2009) Citizen Science: A Developing Tool for Expanding Science Knowledge and Scientific Literacy: https://doi.org/10.1525/bio.2009.59.11.9
  10. Birkin and Goulson (2015) Using citizen science to monitor pollination services: Citizen science and pollination services: https://doi.org/10.1111/een.12227
  11. Maher et al (2019) Using citizen science to examine the nesting ecology of ground-nesting bees: https://doi.org/10.1002/ecs2.2911
  12. Lye et al  (2012) Using citizen science to monitor Bombus populations in the UK: Nesting ecology and relative abundance in the urban environment: https://doi.org/10.1007/s10841-011-9450-3
  13. Merenlender et  al (2016) Evaluating environmental education, citizen science, and stewardship through naturalist programs: https://doi.org/10.1111/cobi.12737
  14. Gardiner et al (2012) Lessons from lady beetles: Accuracy of monitoring data from US and UK citizen-science programs: https://doi.org/10.1890/110185
  15. Burgess et al (2017) The science of 139 citizen science: Exploring barriers to use as a primary research tool: https://doi.org/10.1016/j.biocon.2016.05.014
  16. Law et al (2017) Crowdsourcing as a Tool for Research: Implications of Uncertainty: https://doi.org/10.1145/2998181.2998197
  17. Kremen et al (2011) Evaluating the Quality of CitizenScientist Data on Pollinator Communities: Citizen-Scientist Pollinator Monitoring: https://doi.org/10.1111/j.1523-1739.2011.01657.x
  18. Griffiths-Lee et al (2023) Sow Wild! Effective Methods and Identification Bias in Pollinator-Focused Experimental Citizen Science: https://doi.org/10.5334/cstp.550

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.

Check out more invertebrate research, publications and events from the entoLIVE partner websites:

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A World of Wasps: Researching the Ichneumonid Wasps

Huge numbers of insects are hosts to parasitoid wasps, and one of the most successful groups of wasps is the Ichneumonoidea, or Darwin Wasps. Despite the ubiquity of Darwin Wasps ,they are comparatively neglected by researchers and naturalists. This talk looks at research on species limits in these wasps and how that basic taxonomic work enables new research areas in ecology and genomics.

Q&A with Dr Gavin Broad

Dr Gavin Broad is a principal curator at the Natural History Museum, London, a taxonomist specialising on Ichneumonidae, and one of the co-investigators on Darwin Tree of Life, an ambitious project to sequence the genomes of all UK species.

Are ichneumonids all very host specific or do you have species that are more generalists?

They are often somewhere in the middle and it’s really hard to generalise. For example, within Netelia each species we know any detail about is probably going for a small range of hosts (though fairly closely related in the right habitat). Pimpla rufipes is a really common wasp that attacks all sorts of pupae that are the right sort of size. And not just Lepidoptera – they’ll sometimes go for other orders as well.

Does length of pupation impact which species different ichneumonids will target?

There are so many different factors. For example, you might get a species that has a six-month lifecycle and it needs two host generations a year. In that case, the potential host they could use in the autumn is really restricted to those that are going to overwinter in the correct stage. That’s a life history trait that can determine whether something’s a host or not. If they’re going to attack a caterpillar that then pupates late autumn, then this wasp will emerge in the winter when there’s nothing available for it.

What kinds of defences do the hosts have against these wasps?

There are lots of techniques. One thing that has been studied quite a bit are viruses that have been co-opted by wasps, enabling the wasp to overcome the host’s immune systembecause many insect larvae have quite robust immune systems that recognise foreign objects and encapsulate them. This results in a sort of arms race taking place inside the body of the host – as to how to stop the encapsulation by the host and being destroyed. There are also much simpler defences, if a Netelia puts its egg in the wrong bit of the caterpillar and the caterpillar can reach it with its mandibles, then it’s gone.

What do you need from the wasp in order to sequence it?

The tree within the presentation is based on barcode sequences so that’s a short 650 base pair fragment of mitochondrial DNA, cytochrome oxidase 1. We sequence that gene because it’s pretty informative at the species level. We usually extract the DNA from a leg of the specimen. For older specimens, we are still sequencing the same gene, but we have to use a very different technique to get the DNA in sufficient quantities because it is tiny and fragmented. We have to use a technique called genome skimming.

For genome sequencing, it is not as simple. The specimen has to be ultra fresh and we need to flash freeze it, using dry ice or a -80 degrees Celcius freezer. They freeze very quickly and they’re kept in deep cold until they are sequenced. At that point, the entire specimen is ground up and all of the available DNA is used. We may still sometimes need a second specimen for a DNA top-up. DNA does degrade quite rapidly and because we are using nanopore sequencing for everything, we need big, long strands of DNA for the whole genome. You’re pulling that DNA strand through a little pore in a film and so you want really big, long strands so that you don’t have too many little bits to knit together into a whole genome.

What percentage of parasitic wasps are ichneumonids and what percentage of these are nocturnal?

That’s a good question. In the UK, we’ve got roughly 6000 parasitoid wasps, and 2500 of those are ichneumonids. So, over a third. Not a lot of them are nocturnal. There are probably only around 150 truly nocturnal ones, not counting the ones that fly around at dusk.

Do we have a lot of species where we have little to no ecological behavioural information?

Yes, we don’t actually have any information on what the majority of Ichneumonids are doing. On the flipside, if you start rearing some interesting hosts, you’re almost guaranteed to find some sort of interesting parasitoid wasp and find a new host relationship. Studying Ichneumonids is frontier science!

How did you end up getting into taxonomy and why specifically the taxonomy of wasps?

Wasps was something I fell into. I wanted to be an ornithologist then I wanted to be a lepidopterist. And then I reared wasps, as an undergraduate, interesting parasitoids, and no one could really tell me what they were. I liked that challenge and decided to get into those. I found it fascinating because the whole biology of these things is amazing.

With taxonomy, I saw the word in a David Attenborough book when I was young, Living Planet or Life on Earth. One of those books that I had when I was too young to understand it really. But anyway, it mentioned taxonomists and I was intrigued. I always wanted to be a taxonomist and even when I found out what exactly it did involve, it didn’t put me off. 

Literature References

  1. Broad & Shaw (2016) The British species of Enicospilus (Hymenoptera: Ichneumonidae: Ophioninae): https://europeanjournaloftaxonomy.eu/index.php/ejt/article/view/310
  2. Broad et al (2018) Ichneumonid Wasps (Hymenoptera: Ichneumonidae): their Classification and Biology: https://www.royensoc.co.uk/shop/publications/handbooks/hymenoptera/ichneumonid-wasps-hymenoptera-ichneumonidae-their-classification-and-biology/
  3. Broad et al. (2024) The genome sequence of an icheumonid wasp, Neteli virgata (Geoffroy 1785): https://wellcomeopenresearch.org/articles/9-187
  4. Johansson & Cedreberg (2019) Review of the Swedish species of Ophion (Hymenoptera: Ichneumonidae: Ophioninae), with the description of 18 new species and an illustrated key to Swedish species: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/view/749
  5. Jonsonn et al (2021), A century of social wasp occupancy trends from natural history collections: spatiotemporal resolutions have little effect on model performance: https://nora.nerc.ac.uk/id/eprint/530080/1/N530080JA.pdf

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.

Check out more invertebrate research, publications and events from the entoLIVE partner websites:

More on invertebrates

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Can Passive Acoustic Monitoring of Birds Replace Site Surveys?

The technology used for monitoring the bioacoustics of a site is constantly evolving, with improved hardware, advancing software and growing use of Artificial Intelligence.

Are we heading towards a situation where using sound recorders to passively monitor a site for birds can replace the need for site surveys with human field surveyors?

This blog features presentations from a technology specialist and ecologist, exploring the benefits and limitations of undertaking passive acoustic monitoring of birds on a site. We delve into how these two methods can complement each other and hear case studies where passive acoustic monitoring has been used alongside traditional site surveys.

This blog features two guest presentations:

  1. Wilder Sensing: An Ecologist’s Perspective with Kate Downes (Ethos Environmental Planning)
  2. Wilder Sensing: Innovative Technology To Support Ecologists with Geoff Carss (Wilder Sensing)

Wilder Sensing: Innovative Technology To Support Ecologists

Geoff Carss (Wilder Sensing)

Wilder Sensing is a biodiversity monitoring and reporting tool that uses commercially available sound recorders to record soundscapes, processes the files using Artificial Intelligence to identify what species are present and provides easy-to-use analytic tools to understand the large datasets generated. This enables vast quantities of audio data to be captured and analysed at low cost to ecologists for both short and long-term surveys.

This presentation explores the practicalities and process of bioacoustics together with the results that can be achieved. Geoff Carss will explore some of the issues and limitations such as false positives and negatives, exclusion of under-reported species and bias depending on the species and how to mitigate them. He will also cover how to get long-term time series data sets, how monitoring in urban and industrial environments can cause bias due to background noise and how different filters can limit the identification of scarce species. This session will include a demo of Wilder Sensing where some of these issues will be explored.

Useful links

Q&A with Geoff Carss

  1. Does Wilder Sensing only work for monitoring birds?
    We’ve started with birds as we wanted to develop the model to work well for a single group before branching out. The tool can be used for other groups, but we first need to develop a model for dealing with the sounds created by these groups. The obvious next group would be bats and developing a model to deal with the ultrasonic calls made by various bat species. We’ve been undertaking work to investigate if the tool can be used for specific target species, such as Water Vole, and I’ve got some fantastic recordings of eels using hydrophones that we’re working on. There is also the fascinating emerging subject of soil acoustics, and other organisations looking at pollinator acoustics. The possibilities are vast, but in order for us to produce meaningful outputs we need to first understand the sounds made by various groups and then develop a model to recognise and interpret these.
  2. Do you believe that, with further development, bioacoustics can be used to get measurements of abundance?
    We’ve been recording on one particular site for over two years now. It is a site that has been “re-wetted” and the site managers are interested in how this has impacted the use of the site by Lapwings. We wanted to use the relative frequency of calls as a very rough approximation of abundance, with it being obvious when a flock of Lapwings arrive on the site. We hoped to be able to detect if more flocks were using the site for longer for winter feeding. However, this winter was so wet that the Lapwings were anywhere near the recorder due to the area being flooded out. A direct comparison using core frequency for abundance is pretty sketchy so we’re looking into the benefits of using triangulation, using multiple recorders to establish a measure of abundance. This will be quite the same as what a field surveyor would detect, but it’ll be interesting to see the results of using triangulation.
  3. How much would it cost to get started?
    We’ve deliberately set this up with a simple cost model. We charge a reduced rate of £400 per year for the analysis of data for one recorder for individuals, NGOs and charities. For ecological consultants and other for-profit businesses, we charge £800 per recorder per year. This includes covering the main cost associated with collecting this much data: the storage. We are constantly updating the tool. We don’t provide recorders, but you can use any recorder (such as the Song Meter Micro 2). We are always happy to chat over the Wilder Sensing tool and encourage anyone interested to get in touch.

Wilder Sensing: An Ecologist’s Perspective

Kate Downes (Ethos Environmental Planning)

Traditional field surveys are essential for understanding which species of bird are present on a site and how they are using it. However, these surveys only provide a snapshot in time and are limited by cost and field surveyor availability. Bioacoustic monitoring can monitor a site year-round but may miss things that field surveyors would detect. Kate discusses how Ethos Environmental Planning has developed a hybrid programme of bioacoustic and field surveys for undertaking ornithological site monitoring.

Kate Downes is an Ecologist at Ethos Environmental Planning and an Associate Member of the Chartered Institute of Ecology & Environmental Management. Kate’s specialism is ornithology, in her role at Ethos she leads the design and implementation of bird surveys across the seasons. Her previous work includes studying the Mauritius Kestrel as a field biologist and current work with barn owls helping the South Glos Owl and Bird of Prey Conservation Group (SGOBPC) monitor the species.

Useful links

Q&A with Kate Downes

  1. How does the bioacoustics approach compare financially to the traditional field survey approach?
    That’s an interesting question, and not as straightforward to answer as you might think. We employed a hybrid approach, so we were using Wilder Sensing to complement our field surveys and this past year has very much been a trial for us. For smaller sites, it probably worked out cheaper as we were undertaking fewer field surveys and using the acoustics analysis to inform our reports. For the bigger sites, the recorders were an additional monitoring aspect on top of the usual field surveys and therefore were an additional expense, but gave us so much more data and enabled us to produce more robust reports.
  2. Did you just use Wilder Sensing to analyse the acoustic data, or did you also undertake analysis?
    We only used Wilder Sensing for the projects that I referenced in my talk. However, we did have a validation process for the data provided by Wilder Sensing. For example, if Wilder Sensing included a record of a Curlew at a site where this seemed unlikely we would check that using our own knowledge of as well as other bioacoustic analysis software.
  3. How many recorders would you need for different habitats?
    The guidance mentioned in the talk (see the links above) provides information on this and brings together all of the literature and experiments on this. There are lots of different things to consider here, including cost as each recorder and the data it produces has a cost associated with it. We set all of our recorders a minimum of 250 metres apart to reduce the chance of double counting as advised in the guidance.

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/

Event partners

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

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Bees and Beyond: Ecosystem Services at a Garden Scale

Gardening success and invertebrate activity are deeply intertwined, for better or worse! Demonstrating that the beneficial side of this relationship vastly outweighs the negative is hugely important for maximising the ecological value of gardens – as well as improving horticultural outcomes. Pollination and pest control are the easiest of these ‘ecosystem services’ to illustrate at garden scales. These Buzz Club projects aim to highlight both in practical and entertaining ways.

Q&A with Dr Linda Birkin

Dr Linda Birkin is a specialist in citizen science and urban entomology. She has a particular interest in ecological outreach and wildlife gardening.

Do the bags that you used exclude all pollination, including wind pollination?

I used mesh bags and material so they kept the insects out but allowed wind and pollen to go through. I supplied the mesh material in the first year of the project and in the following two, volunteers provided their own mesh material, including a wedding veil and old net curtains!

Are there any plans to extend the Garden Shop project outside of the UK?

I have had some interest from people in other countries. It is a case of finding a collaborator in that country who can update the cost values. I send the spreadsheet with the cost values stripped out, with instructions to look up local values and put those in. The pollination requirement would still be the same.

Does pet poo provide any food for any invertebrates?

The thing about pet poop is that it depends on the pet. Cat and dog waste, for instance, is predator waste. They are predators that you wouldn’t have at these population numbers naturally and so there’s an unnaturally high level of nitrogen and phosphorous being deposited because of their poop. These shouldn’t be left lying around. Other pets that produce dung, like rabbits, are herbivores and you can compost their poop. It’s something that can go safely back into the environment.

There have been some interesting papers lately regarding dog poop and urine at nature sites and the difference in nutrient spikes in terms of over-fertilisation levels between the side of the path and further in. There are massive spikes in phosphorus and nitrogen just on the sides of the paths. Even if dogs are on a lead, they are still peeing on the side and that has a knock-on effect on the rest of the ecosystem.

There are invertebrates and other living organisms that use animal waste, but the issue is more about how quickly it degrades back into the environment and if it causes problems when it does. Dog and cat poo has quite a high level of bacteria and parasites – many that can cause problems for humans and that you wouldn’t find in that concentration naturally. Worming and flea treatments are another issue. They are designed to, for instance, to kill parasites in the animals but they are not designed to stop once they exit the animal. This is something we are also thinking about researching.

Literature References

  1. Birkin (2018) Pollination ecosystem services and the urban environment: https://hdl.handle.net/10779/uos.23455604.v1
  2. Birkin & Goulson (2015) Using citizen science to monitor pollination services: https://resjournals.onlinelibrary.wiley.com/doi/10.1111/een.12227
  3. Griffiths-Lee et al (2022) Sown mini-meadows increase pollinator diversity in gardens. https://doi.org/10.1007/s10841-022-00387-2
  4. Nicholls et a (2020). The contribution of small-scale food production in urban areas to the sustainable development goals: a review and case study: https://doi.org/10.1007/s11625-020-00792-z
  5. Burton et al (2024) Earthworm Watch: Insights into urban earthworm communities in the UK using citizen science: https://doi.org/10.1016/j.ejsobi.2024.103622.
  6. Gillner et al (2015) Role of street trees in mitigating effects of heat and drought at highly sealed urban sites: https://doi.org/10.1016/j.landurbplan.2015.06.005.
  7. Sheikh et al (2023) Efficacy of green infrastructure in reducing exposure to local, traffic-related sources of airborne particulate matter (PM): https://doi.org/10.1016/j.scitotenv.2023.166598.

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.

Check out more invertebrate research, publications and events from the entoLIVE partner websites:

More on citizen science

Check out upcoming events on Eventbrite