Love among the butterflies

Our economy may still be suffering, but Britain is leading the world in at least one unlikely field: butterfly research.


Last month, the charity, Butterfly Conservation, played host to a vast international gathering of butterfly folk featuring specialists from all around the world, from Ireland to Japan. And the event coincides with the publication of what promises to be our best butterfly book for 20 years, by our top expert Professor Jeremy Thomas and acclaimed butterfly artist, Richard Lewington.
"Butterfly research has truly come of age in the past 20 years," Thomas says. "When I started out, you could count the number of European butterfly scientists on one hand. Now we have 100 people working on one group of butterflies (the Large Blues) alone. And for our new book, I have had to read around 3,000 scientific papers, all published since 1990."

What has happened? "The appeal of butterflies is widening. Once they were mainly a hobby for collectors. But thanks to better cameras, better field guides and close-up binoculars, more and more people, including gardeners, are discovering butterflies, and want to know more."

Thomas was our first full-time butterfly scientist. He cut his teeth on two seldom-seen woodland butterflies, the Brown and Black Hairstreak. "I wanted to know why they were rare. I was engaged to try to solve conservation problems, but as time went on I became fascinated by the wider intellectual challenge of butterflies. Of how they survive in the wild and what evolutionary paths have led to their present life histories."

He is most proud of his role in the reintroduction of the Large Blue. A strange butterfly whose caterpillar feeds on ant grubs during the latter part of its life, it disappeared from its last British site in 1979. With David Simcox, Thomas was able to reintroduce the species from Swedish stock to specially prepared sites in Somerset and Devon. Today it is thriving in several places and has become a great visitor attraction. But the project was successful only because Thomas had thoroughly investigated the Blue's bizarre life and its environmental needs.

Recently, Thomas and his brother Chris have discovered that a related butterfly, the Silver-studded Blue, has an even more intimate relationship with ants. "Chris found that the butterflies lay their eggs near the nests of black ants. They pick up the little caterpillars and take them into the nest where they live for most of the time, creeping out at night to feed on plants. The caterpillar mimics the scent of the ants, guaranteeing it friendly treatment. As prized members of ant society, they get the best of everything." Not that life in the nest is entirely a bed of roses. Thomas has discovered a parasitic wasp – "the most beautiful thing" – that attacks the caterpillars, keeping their protectors at bay with wafts of ant-deterrent vapour.

Thomas has a wonderful film of the butterfly emerging from the nest with ants still clinging to it, tapping the butterfly with their antennae and licking its body. The ants are obviously reluctant to part with their family member. "The more we find out about their secret lives, the more fascinating butterflies are," Thomas says. "Their mating behaviour, their relations with other insects, their long distance migrations (with a newly discovered GPS system in their antennae) – all are proving more intricate and amazing than we ever realised."

With such sophistication at their feeler tips, butterflies are hardened survivors. But today they face a landscape and climate in a rapid change not seen in 10,000 years. Thanks to mapping and monitoring schemes set up by Thomas and colleagues, and sustained by thousands of volunteers, we know what is happening in great detail. The challenge is what to do about it.

Can we save our endangered butterflies? Sir David Attenborough, president of Butterfly Conservation, believes that, in a global context, "things will get worse before they can get better. How can it be otherwise when there are three times as many people as when I was born?" Britain does not have all that many butterflies to lose – only 70 or so species. But as the world leaders in butterfly research and conservation, we surely cannot afford to lose a single one of them.

GOING UP
Brimstone The brightest butterfly of the spring, it thrives in hedges
Red Admiral The warming climate means this butterfly can now hibernate successfully
Geranium Bronze Sightings are increasing of this South African butterfly imported on potted geraniums

GOING DOWN
Small Tortoiseshell Numbers of this familiar garden butterfly have suddenly crashed
Mountain Ringlet Climate change has killed our only mountain butterfly
Pearl-bordered Fritillary It is disappearing and no one fully understands why

The Butterflies of Britain and Ireland by Jeremy Thomas and Richard Lewington is published by British Wildlife Publishing (rrp £14.99)

Bugs Britannica, a national chronicle of bug life by Peter Marren, will be published in May by Chatto & Windus.



By Peter Marren
http://www.telegraph.co.uk/earth/outdoors/7690751/Love-among-the-butterflies.html