WASHINGTON, Feb. 24, 2015-- Bee experts at USDA’s annual Agricultural Outlook Forum last week said better management of crop chemicals could go a long way toward improving the health of this pollinator that is crucial to agriculture, but researching diseases that plague the insect is the best long-term solution.

“Adult honey bees are not living long enough,” said Gordon Wardell, the senior bee biologist at Paramount Farming Co. in Bakersfield, California, as well as the chair of Project Apis m. (PAm), a non-profit organization run by beekeepers that funds and directs research aimed at enhancing bee health.

In California, an estimated 1.8 million honey bees from commercial hives are busy pollinating some 880,000 acres of almond groves during the pollination season that started earlier this month and ends in mid-March. Wardell believes the chemicals that are often mixed in fungicides applied when almond trees are in flower are harming the bees and he is trying to persuade growers to spray only at night, when bees are less active.

Spraying during the day is more directly harmful to honey bees, and can change the scent of the orchard and alter the bees’ forage path, he explained.

Wardell said last year, 80,000 colonies were poisoned during almond bloom.

“We do have to spray fungicides in orchard during bloom,” he said, but the problem is when insecticides are included in the chemical mixture. “Most [colony poisonings] were attributed to tank mixes with fungicides.”

He said he observed bee deaths caused by fungicide mixtures applied over one mile away from his farm.

Rosalind James, of USDA’s Agricultural Research Service, said the labels on fungicides and insecticides are often unclear, or the warnings about bee health are not prominent enough on the label.  

When it comes to reducing bees’ exposure to pesticides, she acknowledged that neonicotinoids are a “very controversial topic,” and said “studies are all over the place” regarding the impact of the insecticides on bees.

Commonly used as a seed treatment for corn and soybeans, she said by the time those plants bloom the level of insecticide in the nectar is gone. Because the effects of the treated seed is gone by late season, growers often use an alternative method to control insects by then. “This is why neonicotinoids are so controversial,” she said. 

Beyond improved labels and best management practices, the most important thing for the industry to focus on is disease management, she said.

“We know what the diseases are, what they do, but we don’t know how to control them,” James said.  The varroa mite, which she called “the most destructive pest in honey bees,” increases the spread of disease and virus throughout a colony.

[Do you find the information on Agri-Pulse helpful? See even more ag and rural policy news when you sign up for a four-week FREE trial Agri-Pulse subscription.]

The phenomenon known as colony collapse disorder (CCD), a syndrome in which worker bees from a honey bee colony abruptly disappear, is still a mystery to scientists, after gaining attention about a decade ago, she noted. Although many possible causes have been identified, “scientists have not been able to induce the disorder experimentally.” While she said it appears occurrences of CCD have declined, it “has brought attention to the plight of pollinators.”

Wardell insisted that no matter the cause, beekeepers are still losing bees at high rates. In 2005, beekeepers were losing 30-50 percent of honey bees, but “they still lose 30 percent of honeybees. What’s changed is beekeepers are making up the difference,” he said. He said beekeepers are producing less honey and are depending more on pollination services to make a profit. 

According to Randy Oliver, a biologist who runs the scientificbeekeeping.com website and manages a 500-colony migratory operation in California, in 2007, the beekeeping industry shifted from primarily being honey producers providers of pollination rental services to California’s almond growers, which produce a crop worth about $5 billion a year.

“The big question each winter since 2004/2005 is whether there will be enough colonies to fulfill the pollination demand, and just how much growers are willing to pay for those hives,” Oliver noted on his website.


For more news, go to www.agri-pulse.com