Cody Dock – Ecology Field Notes

After attending my first Conchological Society of Great Britain and Ireland meeting at the Natural History Museum earlier this year, I stayed behind for a chat with Elliot Newton from Citizen Zoo where the German Hairy Snail project was first proposed. From its inception, the project included further partner organisations, Zoological Society of London, Greenspace Information for Greater London, Port of London Authority, London Wildlife Trust, and other voluntary and community groups, including Cody Dock.

The German Hairy Snail (Pseudotrichia rubiginosa) is a land snail which tends to be found on flotsam along rivers. In the UK, the snail is considered nationally rare and near threatened, being known only from sites along the Thames in Oxfordshire, the tidal Thames in West London, the Roding, and the Medway.

Sites of confirmed records of *Pseudotrichia rubiginosa* on the NBN Atlas map
(Last accessed 23 November 2025)

Hearing the descriptions of habitats where the snail had been found, in both recent and historical sites, I decided that a couple of places near Cody Dock might serve as interesting survey sites. The first, which I thought most likely, was along the banks of what remains of the Channelsea River. The Northern bank of this tidal stretch of water has some fantastic Crack Willow (Salix fragilis) trees, and as such, dead wood and leaf litter tend to collect at the high tide mark. The other site, which seemed more optimistic, was behind the reed bed on the tidal Lea just outside Cody Dock, where scrubbing over had been ongoing for some time.

Once all the partners had been approached, a training day was organised at Syon House – a site in Brentford on the Thames where the snail was known to be found. On the North bank of the Thames, the property was kept as a grazing marsh with many Poplars, Willows, and Swamp Cypress amongst the drainage ditches, an area which the groundskeeper described as “the result of 500 years of benign aristocratic neglect”. Here, we got the opportunity to learn more about the life history of the snail and to trial and hone the survey methodology.

This way for the German Hairy Snail enthusiasts!

The Conchological Society prepared a handy identification guide to German Hairy Snails (and some lookalikes to be aware of), which can be found here. It was a brilliant day, and every participant found a few of the target snail species, as well as a selection of others, which, if not identified in the field, went off to be confirmed by Dr Ben Rowson from the National Museum of Wales. We left Syon House optimistic that we might find these snails in our survey area near Cody Dock.

With volunteers in wellies and hi-vis vests, we then set out to survey the two sites that we had previously considered. At the first site, on Channelsea, we almost immediately found German Hairy Snails in our first 10m² plot. We then surveyed another 4 plots and found the snails in every one of them, with a grand total of 97 recorded at the site! However, our second site, behind the reeds on the tidal Lea, did not produce any German Hairy Snail records.

Volunteers in action – sifting through the debris and plant matter along the high-tide mark at Channelsea River.

It was wonderful to be involved with this project. Many thanks to everyone who helped with the project design and coordination, and to all of our eager volunteers who made the days out in the field so much fun. I am delighted that we were able to add a new site to the distribution maps for this species and hope that these records can support further conservation action along the Channelsea River. I am also very much looking forward to seeing the results from all the other partners involved in the search for this adorable little creature.

Update 24 November 2025: The Guardian newspaper has run an article on the German Hairy Snail project. Follow this link to read the piece.

Furrther update 24 November 2025: The BBC news website has also run an article on the German Hairy Snail project. Follow this link to read the piece.

From February 2023, I will be taking on the role of Biodiversity Officer for the Gasworks Dock Partnership charity based at Cody Dock on the tidal stretch of the River Lea in east London. I will be co-ordinating volunteer opportunities for surveying and monitoring habitats and wildlife of the local area and delivering related training to our network of community scientists.

Not exclusively focused on invertebrates (though you can be guaranteed they will feature heavily) the monitoring will continue the existing bird counts, bat walks, and vegetation surveys that have been carried out so far – there is an excellent report available that covers this for 2021-2022. Plans are afoot to add in Flower-Insect Timed Counts to contribute to the UK Pollinator Monitoring Scheme and various other invertebrate recording schemes.

Habitat management and improvement works will also be part of this job where establishing new reed beds in the Lea will create cover for water birds and serve as a natural filter for some of the litter and pollutants in the river. Silt traps have already been set along the sloped concrete banks and have become vegetated, and we hope to be able to extend this work further along the east bank. Additionally, there are other areas on or near the industrial estate that can be better managed for wildlife and people including woodland, scrub, and parkland which will entail a number of different projects.

Canary Wharf as seen from the Cody Wilds walk along the east bank of the River Lea.

My vision for this stretch of the Lea is that it acts as a green and blue corridor through this part of east London which has a very industrial heritage, but which is now rapidly being redeveloped with high-density housing. The river serves as the boundary between the boroughs of Newham and Tower Hamlets. These are already densely populated areas (Tower Hamlets has the highest density per km of all English districts, while Newham has the 4^th highest population of all the London boroughs) with high levels of poverty (Tower Hamlets has the highest poverty rates in London with Newham ranking 3^rd highest). Consulting with property developers at sites in both boroughs to offset some of the habitat loss caused by building apartment blocks as well as helping to shape a nature-friendly approach to the landscaping will also be part of the job. The loss of post-industrial brownfield sites to development is of concern and we will be working to try to mitigate this through the establishment of green roof systems that mimic traditional brownfield habitat as well as advising on the best use of pocket parks and identifying areas to be set aside as wilder habitats.

Bromley-by-Bow Gasworks which is a classic example of the open mosaic habitats of post-industrial brownfield sites in the area which are being redeveloped into high-density housing.

In other news, I recently took on the role of Woodlouse Recorder for the London Natural History Society with plans to increase records for this group so that we can have a better understanding of their distribution across London. So come along to Invertebrate Field Recorder Days across London and Invertebrate Study Days at the Natural History Museum to learn more about these fascinating crustaceans. I have also recently been elected as a trustee for Bethnal Green Nature Reserve where I will be focused on helping with community-led ecology projects.

Working as FSC BioLinks Project Officer has been a fantastic experience. Some of my highlights over the past year-and-a-bit have been my reintroduction to aquatic invertebrates after spending such a long time focussing on all things terrestrial – there is so much to see underwater, and you get to have a bit of splash about which is especially fun on a hot Summer’s day. Formalising my self-taught ant ID with a number of courses (some of which I even got to teach!) and running my version of an Ant Picnic at Richmond Park where I got youngsters to do science while looking at ants. Rediscovering woodlice, millipedes and centipedes; finding the Downland Villa Bee-fly, Villa cingulata, in abundance at Bushy Park; visiting so many amazing sites in and around London from hidden gems to publicly accessible thoroughfares – the list goes on and on.

Downland Villa Bee-fly (*Villa cingulata*) from Bushy Park in the summer of 2022.

It has been fun and an absolute privilege to work across so many different invertebrate taxa. I recently presented some of the findings from the project at the BioLinks Legacy Conference (the final report will be made available to the public in due course) at the Wellcome Collection in London and am very proud of the work that our team managed to accomplish despite a global pandemic in the middle of our project delivery.

Slide from my presentation at the BioLinks Legacy Conference on 20 January 2023 showing the breakdown of all BioLinks place-based course delivery by invertebrate taxonomic group.

I have learned so much more about a wide variety of invertebrates from national experts (further improving my ID skills) and came to meet a community of people who are passionate, enthusiastic, generous, and knowledgeable about our natural world and the invertebrates upon which we all rely. My sincere thanks to every person who I’ve met along the way and I very much look forward to seeing and working with many of them again in the future.