The UK charity Butterfly Conservation recently surveyed Lambeth’s butterflies and reported finding White-letter Hairstreak (WLH) butterflies at Vauxhall Pleasure Gardens. Lambeth Parks Team planted a new kind of Dutch Elm Disease resistant ‘New Horizon’ elms there about 10 years ago as part of a landscaping improvement scheme. Butterfly Conservation now think the butterflies may be using them as a food plant. This is possibly the first time ever that’s been recorded.
Elm disease drove butterflies into decline
The White-letter Hairstreak (WLH) butterfly is named after the zig-zag lines on the underside of its wings that look like a W (see photo above). It’s been a rarer and rarer sight over the last four decades. Its caterpillars feed only on elm. Since Dutch Elm Disease in the 1970s the number of UK elm trees has gone down more than 30 million – taking butterfly numbers down to 5% of 40 years ago. The WLH is a priority species in the UK Biodiversity Action Plan.
Looking in the treetops
Butterfly Conservation plan to return with a cherry picker to go up and look in the elm trees at Vauxhall Pleasure Gardens for eggs and caterpillars to check if the butterflies have created a successful breeding ground.
Simon Saville, Butterfly Conservation Branch Chair says: “We are excited to have the elusive White-letter Hairstreak in Vauxhall. It is important to know that it can thrive in urban landscapes – it is also at Nine Elms and The Rookery in Streatham Common. This shows that there is nature under our noses, even in city parks”.
For more information
- For more about Lambeth Landscape’s work to preserve and improve the environment for people and for native species of wildlife, see their information pages
- Butterfly Conservation have mapped where White-letter Hairstreaks and disease-resistant elms are found. For a map of the north Surrey area, including Lambeth, see their information pages
- Butterfly Conservation are also developing a project to look at what species live where in inner London boroughs like Lambeth, with the aim of getting more people to look at what’s in the green spaces found in the city. They hope to run “Big City Butterflies – Discovering London’s Butterflies and Moths” from 2019. For information about the project email Butterfly Conservation.