Rare Snail Found on Fly-tip By Thames in Chiswick

Two-lipped door snail makes welcome return to Duke’s Hollow nature reserve

Henry, Hadi and Nathan from the conservation team Picture: Mike Waller/London Wildlife Trust

A rare species of snail has been found by a London Wildlife Trust conservation team living among piles of rubble, the first time it has been recorded in the capital for three years.

The two-lipped door snail is a central European species, very small (1-2cm) but easily recognisable thanks to its elongated shell. Britain marks the northern limit of its range, where it appears to be clinging on in a few select locations. It is associated with riverbank habitats, typically in the tidal Thames area where it can inhabit hedges and scrub, living under logs and rocks.

The Trust conservation team was recently hired by Hounslow Council to improve the habitat for molluscs at Duke’s Hollow nature reserve, near Chiswick Bridge, in the hope of encouraging the two-lipped and another rare species, the German hairy snail. But the team was surprised to discover a number of the snails already at the site, with the first one found grazing on a chunk of concrete near a busy road. Others were later found by a willow tree.

The snail was probably once much more populous along the River Thames, but riverside development and flood-control schemes during the 19th and especially the 20th century have obliterated many suitable locations for both the two-lipped door snail and the German hairy snail. Fortunately nature reserves such as Duke’s Hollow provide a safe haven for these rare snails.

Nathan Nelson, a Trust volunteer who is part of the team which discovered the snails, said: “We found it in the last place we'd have thought to look. We were tidying up around the boundary of the reserve, right by the road, and started moving stones on top of some broken fencing. And there it was, a two-lipped door snail on an old chunk of concrete. At first this would look like fly-tipped builders’ rubble but the snails seem to be perfectly happy there. We cleared a great deal of rubbish from the reserve and we don't want to see any more there, but the snails appear to have made the best of it.”

Councillor Corinna Smart of Hounslow Council said: “What delightful news that such a rare species of snail has been found right here in Hounslow. As a Council, we work closely with the London Wildlife Trust to ensure that we continue to improve areas across the borough to enhance the habitats of wildlife, so it can thrive and residents and visitors alike of all ages can enjoy seeing it.”

There hasn’t been a recording of the two-lipped door snail in London since 2014, and only four sightings have been recorded this century. All have been spotted in the Thames tidal area of west London, including Isleworth and Brentford.

April 7, 2017