The standard method for determining the conservation status of a species is to assess the species against IUCN Red List criteria and apply an IUCN Red List category. These criteria require species data, and many species can therefore only be classed as ‘data deficient’ based on current record holdings. UK earthworms fall into this category and are rarely considered within site management plans, environmental policy or conservation projects.

The Provisional Earthworm Conservation Status Assessment for the UK aims to apply a provisional version of the IUCN categories for all 31 UK species of earthworm based on the little data that we do have and the opinions of the UK’s leading earthworm specialists. This presentation will explore this experimental approach and highlight the benefits and challenges resulting from this project.

Q&A with Keiron Derek Brown

Keiron Derek Brown has been running the National Earthworm Recording Scheme since it was launched in 2014. He has run over 100 earthworm training courses and events since 2014, covering a wide range of subjects including biology, ecology, surveying, identification and recording.

1. How did you get involved with earthworm recording?
   I personally became interested following volunteer work at the Natural History Museum, where I was trained to identify earthworms as part of a research project. When I then did some recording in Cumbria and sent the records to the Earthworm Society, I realised the data wasn’t being used or collated in any meaningful way so I volunteered to take on the role of Recording Officer and set up the National Earthworm Recording Scheme (NERS) in 2014. I’ve stuck with it because earthworms are so important ecologically and nobody else was doing this. I’m proud of the difference that I’ve been able to make due to the dirth of data that came before this.
2. How can others get involved with earthworm recording?
   Earthworm identification does take a certain level of skill and use of a microscope. The Biological Recording Company runs Earthworm Identification courses aimed at beginners, but we understand that the fact that you need to collect, kill and preserve specimens plus access to a microscope is always going to limit the number of people willing to get involved. We also host regular Earthworm Sampling Days where we survey sites for earthworms and contribute data to the NERS database – all of which are free.
3. What is the optimum habit representation within the dataset?
   When I speak about habitats being under-represented, what I really mean is that we have too little data on them. We’d expect more records from some habitats as they account for larger proportions of land use. For example, farmland accounts for 70% of the land in England. We need more information on the earthworm communities that inhabit different habitats, so we need to survey all habitats equally until we have that baseline data. Once we have better information across different habitats, the next step would be to address geographic representation (regardless of habitat).
4. Which species of earthworm are most at threat from development?
   In general, earthworms are not at threat from development. Although development may impact species, for example if areas are concreted over, it is unlikely that this is enough to threaten extinction for most species (even locally). However, the earthworm species that are classed as very rare don’t have much data on where they do and do not occur. If a species has a very small number of locations where it occurs it is particularly at risk from local pressures, such as development, agricultural practices and even habitat management practices on nature reserves. I used development as an example of a potential threat to a species with a few isolated populations in the talk but there is no current known threat from development.
5. Is the classification of species as non/native or invasive based on incomplete information?
   To clarify, none of the non-native species of earthworm found in the UK are classed as invasive as we aren’t aware of them causing harm to UK habitats or native species. Information on global distribution is severely lacking. It is even more difficult to establish the native range of a species because earthworms are moved around so much in soil and sold for fishing bait or compost. I’m only suggesting that 4 of the 31 species found within the UK are registered as non-native species, and this is because they belong to taxonomic groups known to originate from other continents. There are a number of other species that may or not be native – we need genetic studies to help us establish their relation to colonies elsewhere in the world and to establish where they originate from.
6. How would you sum up the status of earthworms in the UK?
   Unknown. This report highlights that there is so much that we still don’t know. We still have big gaps in our knowledge of ecology, distribution and global context. We don’t even know what the natural ranges of many species is. Hopefully, this report will lead to some of these knowledge gaps being addressed so that we can conduct a full red listing exercise on UK earthworm species.

Literature References

• Ashwood et al (2024) Earthworm Records and Habitat Associations in the British Isles: https://doi.org/10.1016/j.ejsobi.2024.103642
• Carpenter et al (2012) Mapping of earthworm distribution for the British Isles and Eire highlights the under-recording of an ecologically important group: https://doi.org/10.1007/s10531-011-0194-x
• Jones & Eggleton (2014) Earthworms in England: distribution, abundance and habitats (NECR145): https://publications.naturalengland.org.uk/publication/5174957155811328
• Sims and Gerard (1999) Earthworms. Synopses of the British Fauna (New Series): https://www.field-studies-council.org/shop/publications/earthworms-synopsis/
• Sherlock (2018) Key to the earthworms of the UK and Ireland: https://www.field-studies-council.org/shop/publications/earthworms-aidgap/
• Bottinelli et al (2020) An explicit definition of earthworm ecological categories – Marcel Bouché’s triangle revisited: https://doi.org/10.1016/j.geoderma.2020.114361
• Capowiez et al (2024) Let earthworms be functional – Definition of new functional groups based on their bioturbation behaviour: https://doi.org/10.1016/j.soilbio.2023.109209

Further info and links

• National Earthworm Recording Scheme: https://www.earthwormsoc.org.uk/ners
• Wriggling Into Recording entoLIVE: https://biologicalrecording.co.uk/2023/02/02/earthworms/
• Digging Through the Dust: Rediscovering Historic Earthworm Records in Museums and Publications: https://youtu.be/Cw7MoK07yQs
• UK earthworm datasets on GBIF: https://www.gbif.org/publisher/0b8171d0-6b32-4ccc-bf3d-bf34b56c36d3
• Earthworm ecology: https://www.earthwormsoc.org.uk/earthworm-ecology
• IUCN Red List Categories & Criteria: https://www.iucnredlist.org/resources/categories-and-criteria

More for environmental professionals

Britain’s endemic invertebrates are the crown jewels of our biodiversity. There are 22 endemic species ranging from the Turk’s Earth Centipede (Nothogeophilus turki) to the Manx Shearwater Flea (Ceratophyllus fionnus). Last year Buglife undertook global IUCN Red List assessments for 20 of these species. This presentation will explain the assessment results and introduce participants to these amazing species.

Craig Macadam is Conservation Director with Buglife where he oversees all practical action and advocacy to restore invertebrate populations. He is the national recorder for mayflies, stoneflies and leeches, and represents Buglife on a number of fora including the IUCN Species Survival Commission and the IUCN Task Force on Global Freshwater Macroinvertebrate Sampling Protocols.

Q&A with Craig Macadam

1. Are there many additional invertebrate species that are considered endemic to the British Isles rather than just Great Britain?
   There are a few. Off the top of my head, I think there are a couple of beetles and a moth that are found in Ireland. I’ve been chatting to people in Ireland to enquire if there is a list of species that are endemic to Ireland so that we can cross reference this with our lists of UK species.
2. Has the Manx Shearwater Flea (Ceratophyllus fionnus) been searched for on the Calf of Man?
   There have been very brief investigations of nest material at most of the Manx Shearwater (Puffinus puffinus) sites. However, there is a need to look at this in more detail, particularly in places like the Calf of Man, Skomer and other Manx Shearwater roosts. A lot of the existing work on this was done in the 1960s and 1970s, with the most recent data from the Isle of Rum. You would need a licence to take the material and we’re in discussions with the RSPB about how this could progress.
3. What is the current state of data for UK endemic invertebrate species?
   It is a really mixed bag. For some species there is really regular monitoring, such as the Environment Agency monitoring of freshwater invertebrates. There are also some really active recording schemes that target some of these species, for example, Lee Knight is looking for the British Cave Shrimp (Niphargellus glenniei) in sites all over southwest England and he’s generated a great dataset. The active Dipterist Forum recording schemes involve surveys going on in areas where these species should be picked up if they are present so if they are not detected we can infer that they are absent.
4. How do you establish that a species is endemic and not present elsewhere?
   It took a while! Every time I thought that I had my list completed, I’d receive emails from people asking about other species. We contacted experts across Europe and did a very extensive literature search, including looking at specialist journals for the various groups. Luckily, for some species there had been European or global reviews of the families which allowed us to get really up-to-date information. There are still other species on the long list that could be endemic but we don’t have enough information on them to state confidently that they are.
5. Are there any key actions that the public or conservationists can take to support our endemic invertebrates?
   I’d advise people to support the efforts of invertebrate NGOs. At the moment we have the campaign to protect the Fonseca’s Seed Fly (Botanophila fonsecai) and save Coul Links from development, where over 11,000 people across Scotland and the UK have written to the Planning Minister urging him to call-in the application, resulting in a public inquiry. If you’re interested in a specific endemic species and record that group, keep an eye out for it and ensure that your data is making its way to the NBN Atlas.
   

Literature References

• Macadam (2023) Britain’s Endemic Invertebrates: https://cdn.buglife.org.uk/2023/11/Endemic-Species-Report-2023-Final.pdf

Further info and links

• Buglife: https://www.buglife.org.uk/ 
• IUCN: https://www.iucnredlist.org/en 
• IUCN Red List Categories and Criteria: https://www.iucnredlist.org/resources/categories-and-criteria
• IUCN Red List Criteria summary sheet: https://www.iucnredlist.org/resources/summary-sheet

More for environmental professionals

This second iteration of the Natural England Field Unit (NEFU) will celebrate its tenth year in 2024. NEFU currently has 5 entomologists working on condition assessments for the organisation, as well as contributing to a host of other entomological work, including DNA work, supporting PhDs, training and a range of other work. Pete will introduce a range of this work, showing the valuable entomological work NEFU does.

Pete Boardman FRES has worked in the Natural England Field Unit (NEFU) since 2016, having previously run a number of training projects at the Field Studies Council for a decade, and freelanced for thirteen as an entomologist. He was until recently national recorder of the Cranefly Recording Scheme, and has extensively taught various entomological subjects for Natural England, Universities, Wildlife Trusts, etc.

Q&A with Pete Boardman

1. Do the SNCOs for Northern Ireland, Scotland and Wales also have equivalent field units?
   I don’t believe there are equivalent field units in Northern Ireland or Scotland. They will have funding to contract out services where needed, rather than delivering surveying in-house. In Wales, they have a team of desk-based staff that undertake surveys from existing data and aerial maps. We’re very aware that we are lucky to have this team in-house as a country agency, and it is worth reiterating that the NEFU doesn’t undertake all of our invertebrate site surveys and we still need to contract out these services once we’ve reached our capacity.
2. Are there any freshwater specialists in the NEFU?
   We don’t have anybody within the field unit but always try to campaign for people with freshwater expertise as there are potential jobs that we could do if we had somebody with these skills. Currently, the freshwater work that NE undertakes would be contracted out to freshwater ecologist contractors.
3. Are you using any technologies to speed up the identification?
   Most of our methods involve traditional identification using a microscope, particularly due to the complexities of trying to identify small invertebrates in the field. The large point of what we do with the Natural History Museum is to increase the databases so that in the future we are able to get a species list from DNA analysis of the malaise trap catch.
4. Do you undertake any identification in the field?
   We are limited as to what we can do in the field because most of what we are looking at needs observation under a microscope. However, where we can identify a specimen in the field we will try to do so and release it once it is identified. We usually have an idea of which high-fidelity species we are likely to find on site so we can be on the lookout for these to limit the number of specimens that we take of these. As an entomologist becomes more experienced, the chances of them collecting rare specimens becomes lower as they have a better idea of what they’re looking for.
5. Can you impose a site designation if the landowner opposes it?
   Natural England does have the power to do this. It can get quite expensive as it needs to go through the courts and we’d need to engage with legal experts.

Further info and links

• Pantheon invertebrate assemblages tool: https://pantheon.brc.ac.uk/
• iRecord: https://irecord.org.uk/
• Instagram: https://www.instagram.com/nefieldunit/
• Twitter/X: https://x.com/i/flow/login?redirect_after_login=%2Fnefieldunit
• Stratiomys singularior: https://species.nbnatlas.org/species/NBNSYS0000007840
• W114: https://pantheon.brc.ac.uk/lexicon/stream-river-margin
• W126: https://pantheon.brc.ac.uk/lexicon/seepage
• Glanville fritillary: https://butterfly-conservation.org/butterflies/glanville-fritillary

More for environmental professionals