Sunday, March 9, 2014
By MECHELE COOPER Kennebec Journal
Beekeepers need to be especially careful this year.
Roy Cronkhite of Livermore Falls checks one of his hives Saturday to make sure the queen bee had plenty of empty cells left in the wooden frames of the hives to deposit eggs. He pulled out three frames until he found the queen.
Joe Phelan/Kennebec Journal
A mild winter and unseasonably warm early spring have created conditions reminiscent of 2010, when beekeepers were caught off guard from an explosion of mite populations that killed off many honeybee colonies, according to a state expert.
"The bees are coming out, but so are the parasitic mites," said Tony Jadczak, state apiarist and bee inspector. "What I've seen in my inspections is elevated mite loads because of the good health of the honeybees. If it tracks like it did in 2010, we'll have a huge die-off in the fall and winter."
Varroa is one of the external parasitic mites that attacks European honeybees, along with nosema, an intestinal parasite, Jadczak said.
He said most hives were strong in 2010 at the onset of the late spring and summer. Then, in mid- to late July, hive inspections indicated that many colonies were at or approaching levels at which they needed treatment for varroa mites, Jadczak said.
Those levels were reached at least a month earlier than normal.
Jadczak said this year the bees are eager after the mild weather, the same as in 2010; so he's advising Maine beekeepers to monitor their hives.
When the mite count exceeds recommended levels, it's time to treat with soft chemicals, which are mainly organic acids from plant oils.
Jadczak said bees should be managed according to weather conditions and plant phenology, not the calendar date. And monitoring varroa is crucial because mite populations can explode under certain circumstances, he said.
Jadczak said Maine beekeepers have suffered major losses since the parasite from the Asian honeybee was introduced into the United States in the mid-1980s. He said there's also a viral complex associated with the exotic mite that honeybees in the U.S. have no defense against.
"Continue to monitor, but be ready to treat when the summer crop is done mid- to end of July, if we parallel 2010, which seems like what's going on," he said. "Weather is a big factor. Based on what I'm seeing, (bees are) running ahead of schedule."
Parasitic mites are not the only concern for beekeepers.
The Maine Organic Farmers and Gardeners Association also is warning people about a class of pesticides that are increasingly linked to problems surrounding bee health, specifically a phenomenon called colony collapse disorder.
Russell Libby, executive director of MOFGA, said each year since 2006, U.S. beekeepers have lost on average a third of their hives.
At least one commercial beekeeper qualified for disaster relief from the U.S. Department of Agriculture because the loss of hives last year was so great.
Libby said Maine doesn't have enough bees in the state to pollinate all the crops, so 70,000 bee hives are brought in by commercial beekeepers every year. Libby is urging people to contact Maine's congressional delegation and ask that they pressure the U.S. Environmental Protection Agency to take swift action to protect the honeybee.
"The big issue really is to have EPA look more closely at these materials as they're approving pesticides for use," he said.
The Harvard School of Public Health released a study earlier this month that said the likely culprit in worldwide declines in honeybee colonies since 2006 is imidacloprid, one of the most widely used pesticides.
Bees are exposed to imidacloprid, which belongs to the group of pesticides called neonicotinoids, when they feed on nectar and pollen. The pesticide interferes with the transmission of stimuli in the insect's nervous system and results in convulsions, paralysis and eventually death. The study is scheduled to appear in the June issue of the Bulletin of Insectology.
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