Butterfly Colonies RelocatedIn Experiment in ‘Assisted Colonization’

British scientists have successfully relocated butterfly colonies 40 miles north of the previous limit of their range in what is reportedly the first instance of assisted colonization in the face of global warming. A team of researchers transplanted colonies from two species — marbled white butterflies and small skipper butterflies — to a more northerly location that computer models had predicted would be good habitat for the insects. Relocated in 1999 and 2000, the butterflies “have become established and are thriving,” according to Brian Huntley of the University of Durham. The study, reported in the journal Conservation Letters, said the butterflies’ arrival in the new locale has apparently had no adverse effects on other species. Some ecologists now maintain that numerous species will need to be moved to more northerly locales, or higher elevations, to avoid extinction in a warming world.