A butterfly bonanza
With news that UK butterflies are on the decline, we visit one innovative project that’s created a thriving population of these colourful creatures
From red admirals to holly blues, common brimstones to speckled woods, there’s nothing quite like seeing butterflies to cheer up our day. They’re the splash of pretty colour that brightens our landscape and a vital cog in nature’s ecosystem turning day in, day out. Yet these remarkable creatures are having a tough time at the moment, with threequarters of British butterfly species in decline and four species wiped out in the last 150 years. That’s the result of their habitats being destroyed through urban development and by over-tidy gardens. In addition, unpredictable weather resulting from climate change is now threatening their very survival. Now more than ever they are in need of a little loving care and support.
One project doing its bit to help the future of butterflies is Winterbourne Downs, a chalk grassland site in Wiltshire managed by the RSPB. Since December 2005, a team have been converting this arable farmland into a butterfly paradise, making the most of the
chalk soil already found in the area and bringing in more of it to boost the butterfly population.
“In nutrient-rich soil, you find that only the strongest, most competitive flowers prosper. With well-drained, poorer soil like chalk, however, there’s a chance for
all different kinds of flowers to grow, including lots of wildflowers that butterflies need and love, which wouldn’t survive elsewhere in stronger soil,” says Patrick Cashman, site manager at Winterbourne Downs. Over the past few years, staff and volunteers here have been digging up chalk to create two S-shaped butterfly banks in which they then sow the seeds and wild flower plugs of plant species they know send butterflies crazy, including kidney vetch, horseshoe vetch, hairy violet and rockrose.
And it’s proved a huge hit! Winterbourne Downs has since attracted 25 species of butterfly (out of 59 in the whole of the country) including some very rare butterflies, such as the Adonis blue, the small blue and marsh fritillary. What’s even better is that volunteer monitors have also discovered many of the butterflies are also laying their eggs and setting up a new colony here – a sure sign that they’ve made themselves right at home! “We think most of the butterflies here have travelled from nearby Porton Down, which is another haven for butterflies, on a north-easterly wind. They’re attracted to the habitat as we’ve planted the flowers that they and their caterpillars love to feed on so their caterpillars can absorb strong flavours into their body. Hence predators are less likely to eat them. “While a few years ago we had one or two small blue butterflies on the site what’s great is that they’re now everywhere. There can be as many as 50 on our butterfly bank on a sunny day, which means they must have bred and bred.” Brilliantly, Winterbourne has also become a sanctuary for other wildlife, including bees, spiders and beetles as well as being the home of the rare farmland bird, the stone curlew.
And while Winterbourne is an example of a large-scale project helping butterflies, Patrick is keen to point that you don’t need 200 hectares of chalk grassland to do your bit for these lovely creatures. “You can make a difference just in your garden by planting some nectar-rich flowers like we did – try lavender, phlox and verbena bonariensis. It’s also good to keep an area of uncut lawn which all kind of wildlife and flowers will love.”
RSPB’s Vanessa Amaral-Rogers and site manager Patrick Cashman
Winterbourne volunteers sow wildflower seeds on the side of a chalk bank to attract butterflies
An Adonis blue alights on a plant. Right, voluntary warden Roy Williams