The numbers of four common species of bumblebee in the U.S. have dropped 96 percent in the past few decades, according to the most comprehensive census to date. The decline surprised scientists, and it has major implications for the pollination of wild and farmed plants.
The declines are likely the result of disease and low genetic diversity of bee populations, scientists say. Bumblebees are key pollinators of wild plants and agricultural crops; bees in general pollinate around 90 percent of the world’s commercial plants – including most fruits, vegetables and nuts.
The cause of a broader, worldwide decline in bees and other pollinators such as moths is still rather uncertain, but scientists believe it is a combination of new diseases, changing habitats around cities, and increasing use of pesticides.
Here’s an episode of Oregon Field Guide on the disappearance of Oregon’s native bumblebees: