Seventy-five percent of butterfly species in the United Kingdom are in decline, according to a study published this week in the journal Nature. Some experts had expected butterflies to be doing well as a result of global warming, because milder weather was expected to increase the ranges of many species. But temperature increases in the U.K. haven’t been enough to compensate for habitat loss. The study, which was coordinated by Butterfly Conservation and three British universities, attributed the diminishing number of butterflies to the destruction of meadows, woodlands, and moors, and warned that without significant intervention many species would become rare or extinct.