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Snailspotter’s rare find on PLA’s Thames Island

  • RSPB expert uncovers snail on Oliver’s Ait, Hounslow
  • Ait has been helped by £30,000 PLA environmental management program.

The Port of London Authority (PLA) recently stepped in and took nature boffin James Harding-Morris to its mid-Thames island, Oliver’s Ait, to help him on a year-long, countrywide search to see every one of the UK’s 100-plus species of land snail. And he was definitely on the right track, finding the Thames Door Snail (Alinda biplicata).

James joined the PLA’s environment team during one of their regular visits to the island – a narrow, 120-metre long haven near Kew Bridge. The team regularly surveys the Ait to see how wildlife on it, including many breeding Canada geese, cormorants and mute swans, is thriving after the first three years of a £30,000 environmental management programme – which has involved tree husbandry and river wall improvements. A pre-works survey by London Wildlife Trust on Oliver’s Ait had shown the presence of rare Swollen Spire and Thames Door Snails.

James, schools project officer for the Royal Society for the Protection of Birds (RSPB), reached the Ait with the PLA team on board a harbour launch. After just 45 minutes’ searching he found the Thames Door Snail. Measuring just a few centimetres long, it’s a species that’s almost exclusively found at sites along the tidal Thames. Unfortunately the other species he was hoping to see, the German Hairy Snail (Pseudotrichia rubiginosa) that experts believe is on the Ait but hasn’t been recorded there, eluded him on the day.

James said: “It was great to get out to a Thames island with the PLA – something I would’ve struggled to do myself. Finding the Thames Door Snail was great – it was the 37th snail of my quest and the search continues. The Ait is an amazingly peaceful nature haven in the city and, in the couple of hours I spent there; I found seven other species of more common snail, as well as the highest density of the ominous-looking Devil’s Coach Horse Beetles I’ve ever seen.”

Since visiting Oliver’s Aid James has made his 38th snail species find, the Wall Snail (Balea perversa) in the shadow of Bolton Castle near Wensleydale, North Yorkshire.

PLA environment manager Tanya Ferry said: “James’ Thames Door Snail find demonstrates Oliver’s Ait’s importance as a haven for all types of creatures. Our management programme is all about sustaining and improving the island environment as a habitat for many species of wildlife.”

For Hi - resolution photos please click on image

For further press information, please contact

Gareth Dorrian
Corporate affairs writer
Port of London Authority
01474 562 251/07711 640 099


Tom Conroy
Communications Manager
Corporate Affairs Dept
Direct Line: 01474 562246
Mobile: 07951 748904
Email: tom.conroy@pla.co.uk