By the first week of May, more than 50 reports had been submitted to the Ontario Bee Association (OBA) and its affiliates regarding hive deaths. Tests were taken, and it was discovered that a spike in deaths occurred when corn farmers were air-seeding their crops nearby.
When rainfall is consistent, a portion of pesticides tend to get washed away. That didn't happen this year, and some experts believe that a lack of snow over the winter, followed by an unusually dry start to spring across southern Ontario, has exacerbated problems for bees.
Bill Ferguson is a commercial beekeeper near Hensall who sat on the OBA Board of Directors. He says that when large quantities of the corn pesticide neonicotinoid gets picked up by the wind it can literally make the air "poisonous to bees."
"We've found the corn treatments can enter the bloodstream of the bee and cause paralysis. The result is something similar to Alzheimer's disease in humans. The bees are unable to move and they can't make it back home," he says.
Other experts are hesitant to link bee deaths exclusively to neonicotinoids.
Researchers at the University of Guelph have theorized that a variety of factors - including insufficient bee feeding and small colony numbers prior to the start of winter - are contributing to bee deaths.
Dr. Leonard Foster, an assistant professor of biochemistry at the University of British Columbia, says that while there is "anecdotal evidence" of bees dying from pesticides, more study needs to be done.
"In short, the jury is still very much out on this," he says. "I have been hearing about a lot of cases that attribute dead bees to specific pesticides, but there is not a lot of evidence to back those claims."
Some experts have linked mass beehive deaths to the varroa mite, a parasite that attacks bee colonies during the late spring and early autumn. Others are looking at how environmental factors - such as cell phone radiation -are impacting the bee population.
Regardless, Bill says we need to pay more attention to the pesticides that are used in Canada, because neonicotinoids may pose a problem to other species as well.
"We've seen birds feeding in the bee yards and like everything in nature, they target the weakest. They see bees that can't move very fast and they pick those off," he explains. "We found a dead robin in our yard, and we've heard some other preliminary reports of bird deaths in other yards."
The lab results on the bird deaths have yet to be published, but the working hypothesis among beekeepers is that the birds are dying from feeding on contaminated bees.
Several European countries have banned neonicotinoids, and while bee populations appear to be rebounding in those places, the next course of action for Canada remains unknown. Presently, the government is seeking input from experts on how to best minimize bee deaths.
"Right now, we're waiting to see what happens in Canada," Bill says, "because bees play a huge role in our ecosystem. At least a third of our food comes from bees and their pollen, and we can't afford to kill off our natural pollinators."