Managed honey bee colonies suffered annual losses of 42 percent, with summer declines outstripping winter losses for the first time, the U.S. Department of Agriculture reported Wednesday.
The declines are less steep than those seen when colony collapse disorder first was recognized in 2006, but remain troublesome, driving up prices for crop pollination services, according to the department.
“Beekeepers in some cases are replacing half their operations during the year,” said Jeff Pettis, a senior research entomologist at the USDA Agricultural Research Center’s Bee Research Laboratory in Beltsville, Md.
California has the largest number of beekeeping operations in the country. Its almond industry, the single-largest user of honey bees, paid more than $292 million for pollination services in 2012, according to the USDA.
Prices for colony rentals for a 3- to 5-week pollination period ranged from $140 to $200 last year, depending on colony size, according to the online beekeeping community Beesource.com.
Summer colony losses averaged 27.4 percent, based on the agency’s annual survey, which included more than 6,100 beekeepers managing 400,000 colonies — about 16 percent of the colonies managed nationwide.
The decline outstripped the 23 percent winter loss, according to the survey.
“We’ve always known that we had summer losses,” Pettis said. “We just never tried to quantify it before.”
Although winters are stressful for hived bees, summer is the time when colonies are moved from crop to crop across multiple states.
“That pollination workload is certainly part of it,” Pettis said. “That’s a lot of work.”
In addition to the summer losses, entomologists are puzzling over reports of unusually high rates of queen loss, which can doom a colony.
“Queen honeybees are either dying in the colony or being replaced,” Pettis said. “They’re failing for some reason.”
A 2012 USDA study attributed colony collapse disorder to multiple factors, including beekeeping practices, parasites, viruses and exposure to agricultural chemicals such as neonicotinoid pesticides.