Americas butterflies are disappearing at catastrophic rate

America’s butterflies are disappearing because of insecticides, climate change and habitat loss, with the number of the winged beauties down 22% since 2000, a new study finds.The first countrywide systematic analysis of butterfly abundance found that the number of butterflies in the Lower 48 states has been falling on average 1.3% a year since the turn of the century, with 114 species showing significant declines and only nine increasing, according to a study in Thursday’s journal Science.“Butterflies have been declining the last 20 years,” said study co-author Nick Haddad, an entomologist at Michigan State University.“And we don’t see any sign that that’s going to end.”A team of scientists combined 76,957 surveys from 35 monitoring programs and blended them for an apples-to-apples comparison and ended up counting 12.6 million butterflies over the decades.

Last month an annual survey that looked just at monarch butterflies, which federal officials plan to put on the threatened species list, counted a nearly all-time low of fewer than 10,000, down from 1.2 million in 1997.Many of the species in decline fell by 40% or more.David Wagner, a University of Connecticut entomologist who wasn’t part of the study, praised its scope.And he said while the annual rate of decline may not sound significant, it is “catastrophic and saddening” when compounded over time.“In just 30 or 40 years we are talking about losing half the butterflies (and other insect life) over a continent!” Wagner said in an email.

“The tree of life is being denuded at unprecedented rates.”The United States has 650 butterfly species, but 96 species were so sparse they didn’t show up in the data and another 212 species weren’t found in sufficient number to calculate trends, said study lead author Collin Edwards, an ecologist and data scientist at the Washington Department of Fish and Wildlife.“I’m probably most worried about the species that couldn’t even be inclu...