Finally, a suspect in bee decline

Mites in carcasses cited by University of Guelph entomologist Published On Sun Jan 24 2010 STAR.Com

Especially if it's about Colony Collapse Disorder, the mysterious vanishing act that's decimated almost 30 per cent of the northern hemisphere's honey producers and pollinators since late 2006. In the past two years alone, hundreds of books have been published on the plight of domestic honeybees. And if, as the saying goes, the sunny little insects are responsible for one forkful of every three bites of food you eat, that doesn't bode well for the myriad crops in Canada that rely on them for pollination. Despite this, Ernesto Guzman, an entomological researcher at the University of Guelph, is skeptical that CCD actually exists.

"CCD is an arbitrary name," he says, "designed by U.S. scientists to define a high mortality of colonies that have no explainable reason. "Radio waves, even terrorist plots" are among some of the theories. Bees across Canada have declined by 30 to 40 per cent every spring since 2006. After a busy fall of stashing nectar and pollen for the cold months to come, bee colonies get swathed in thick, black wrap for winter hibernation, only to be found dead in the first melting weeks of February and March. "If you're a dairy farmer," says Tim Greer, president of the Ontario Beekeepers Association, "imagine losing between 30 to 40 per cent of your dairy cows each year. That's a significant loss." Guzman acknowledges that we have a problem. But the Mexico-born bee expert suggests scientists are stuck in nomenclature.

Canadian officials, meanwhile, insist our bees aren't suffering from CCD for one main reason: they aren't disappearing. "The main symptom among CCD cases described in the States is that they don't find corpses," says Guzman. "It's like they have died in the field and they never came back. "We don't see that in Canada, I believe, because in the winter they cannot fly out." A good thing for us, says Guzman, because corpses can be studied, and since the fall of 2007 he has been doing just that. He followed 413 Ontario bee colonies for a year and recorded their fates, studying up-close the 27 per cent of hives that didn't survive winter. In a report to be published in the journal Apidologie, Guzman identifies what killed them: the varroa mite, a crab-like parasite the size of a pen dot. Abetted by poor bee populations and low food reserves for the winter, Guzman says, the bee bloodsucker is without question why colonies in Ontario, at least, are dwindling so fast.

Ed Nowek of Planet Bee apiaries in Vernon, B.C., ventures the same conclusion for his side of the country. "I've never seen it so hard to keep bees alive than in the past four to five years," he says of his 30-year run in the business." Though the mite isn't new, beekeepers say what's most disconcerting is the probable cause behind its sudden explosion: a built-up resistance to the chemicals used to kill them. For the same reasons some hospital patients succumb to antibiotic-resistant bacteria such as MRSA, varroa has become the superbug of Canada's bees. And though Apivar, a miticide used in New Zealand and Europe, seems to do the trick on Varroa, it's strictly regulated by Health Canada's Pest Management Regulatory Agency. Perhaps rightly so: there's no telling how long it will be effective for.

But, as Greer says, "there's nothing else we can do. Other than wait another winter and see what the results are." Last November, as temperatures dipped in Ontario, the bees began to cluster. He sprayed them with the Apivar, fed them a little extra sugar syrup and tucked them in for the winter, hoping that by spring they'll be buzzing when he comes to unwrap them.

Current Emergency Registrations for British Columbia

Crop	Pest	Registrant	Product Name & PCP#	Active Ingredient	Dates of Registration

Beehives

Varroa mites

Veto-Pharma

Apivar PCP #29092 (PDF)

amitraz

July 1, 2009 to June 30, 2010