Nearly half of all insect species worldwide are in rapid decline and a third could disappear altogether, according to a study warning of dire consequences for crop pollination and natural food chains.
“Unless we change our way of producing food, insects as a whole will go down the path of extinction in a few decades,” concluded the peer-reviewed study, which is set for publication in April.
The recent decline in bugs that fly, crawl, burrow and skitter across still water is part of a gathering “mass extinction,” only the sixth in the last half-billion years.
“We are witnessing the largest extinction event on Earth since the late Permian and Cretaceous periods,” the authors noted.
The Permian end-game 252 million years ago snuffed out more than 90 percent of the planet’s life forms, while the abrupt finale of the Cretaceous 66 million years ago saw the demise of land dinosaurs.
Experts estimate that flying insects across Europe have declined 80 percent on average, causing bird populations to drop by more than 400 million in three decades.
“We estimate the current proportion of insect species in decline — 41 percent — to be twice as high as that of vertebrates,” or animals with a backbone, Francisco Sanchez-Bayo of the University of Sydney and Kris Wyckhuys of the University of Queensland in Australia reported.
“At present, a third of all insect species are threatened with extinction.”
An additional one percent join their ranks every year, they estimated. Insect biomass — sheer collective weight — is declining annually by about 2.5 percent worldwide.
“Only decisive action can avert a catastrophic collapse of nature’s ecosystems,” the authors cautioned.
Restoring wilderness areas and a drastic reduction in the use of pesticides and chemical fertiliser are likely the best way to slow the insect loss, they said.