The survey represents about 15% of the total bee colonies in the U.S., with about 6,000 beekeepers responding. Of beekeepers with under 50 colonies ("Backyard beekeepers"), the varroa mite was majorly responsible for the decline. However, it is unknown why commercial beekeepers had substantial losses.
|varroa mite (Varroa jacobsoni) on honeybee by Pest and Diseases Image Library, Bugwood.org|
Source Article: U.S. beekeepers lost 40 percent of bees in 2014-15