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The butterfly effect

Well, something must be terribly wrong, because butterfly populations are plummeting around the globe.


 

“A lot of people view butterflies in a way analogous to the canary in the coal mine,” says Arthur Shapiro, an entomologist at the University of California at Davis. “If butterflies are going downhill, something is wrong.” Well, something must be terribly wrong, because butterfly populations are plummeting around the globe. The graceful fluttering of the marsh fritillary and delicate beauty of the Grecian copper could soon be squashed out, and the large tortoiseshell, a spotted orange butterfly once ubiquitous in England, is now classified as regionally extinct.

In Europe, where there’s a wealth of data thanks to a decades-long culture of professional and hobbyist butterfly monitoring, scientists are reporting a 70 per cent reduction in populations across the board. Four of Britain’s 62 species of butterflies have gone extinct in recent years, while a further 19 are threatened and 11 near threatened. North American scientists report similar numbers.

Intensive farming is believed to be the primary culprit in England and Western Europe, where subsidies from governments and the EU support mega-farms that strip grasslands, the habitat for many species of butterfly. “Europe has been inhabited for thousands of years and the natural environment adapted to that,” says Chris Van Swaay, a spokesperson for Butterfly Conservation Europe.

Climate change is also taking its toll, pushing many species of European butterflies north to cooler weather and forcing the mountain butterflies of North America into higher elevations. But, says Shapiro, they can’t keep running forever, and many species require too specialized a climate to run at all.

The decline probably won’t have much impact on the food chain, but butterflies are indicative of the health of insects as a whole, and many other grassland bugs that aren’t as thoroughly monitored could be undergoing similar losses. And according to Van Swaay, the downfall of butterflies does signal the first death rattles of scenic grasslands in Europe and North America. “If you like your children to enjoy fields with flowers and butterflies, seeing birds fling along and singing in the trees,” he says, “then you have a problem.”


 
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