Published by Communications and Public Affairs (519) 824-4120, Ext. 56982 or 53338
August 10, 2000
'Survivor' bees hope to make it off island, save Canadian cousins
A University of Guelph researcher is hoping French immigrants now in hiding on an Ontario island will provide a solution to a deadly predator killing Canada's honeybee populations.
The varroa mite is a parasite that has devastated honeybee colonies worldwide in the last 20 years, and until now, commercial beekeepers have been forced to use insecticides to slow the infestation.
But Guelph environmental biology professor Gard Otis believes he and a colleague may have found a natural, genetically based way to beat the mites. Last year at an international beekeeping conference, Otis learned from French scientist Yves Le Conte that wild bee populations in several regions of France have rebounded over the last seven years.
"This was the first solid report of untreated European honeybee colonies thriving in the presence of varroa mites," Otis said.
While the reasons for the apparent resistance are unknown, Otis and Le Conte initiated a dual research project to determine if the resistance is genetically based and can be bred into Canadian bee strains.
Earlier this summer in France, they exchanged uninfected queen bees and are now rearing sister colonies infested with mites in each country.
But to meet strict Agriculture and Agri-Food Canada regulations -- which do not generally permit the importation of bees -- the French queens brought to Canada have been placed in quarantine on an island far enough from the mainland to be beyond a honeybee's normal flight range. "The isolated location minimizes risk, ensuring that we aren't bringing in any other disease or pest," Otis said.
He and Le Conte will study the growth rates of mite populations in both French and Canadian bee colonies as the first step toward breeding resistant colonies. "I'm hopeful for the first time in years," Otis said. "My colleague in France showed me seven wild colonies near to his home with healthy populations. The bees carried the mites but were unaffected by them."
Although only about the size of a head of a pin, varroa mites can destroy a hive of tens of thousands of bees in as little as six months. The parasites feed and reproduce off the blood of the pupae. Those that survive grow into adults with low weight, deformities and a greatly reduced lifespan.
The mites are thought to have originated in eastern Russia, but quickly moved across the continent to engulf all of western Europe. First detected in the United States in 1987, and in Ontario four years later, varroa mites have virtually wiped out wild honeybee populations, and commercial beekeepers are surviving with the use of chemical treatments that slow the infestation.
Besides producing honey, bees play an essential role as pollinators in fruit and vegetable production. It is estimated that honeybees account for 80 per cent of all insect pollination of fruit and vegetable crops and are responsible for ensuring approximately one-third of our food supply. U.S. figures released this spring valued honeybees as pollinators for $8 billion to $10 billion worth of annual farm crops in that country alone.
Because of the economic importance of bees, "nearly half the honey bee scientists in the world are working on varroa mites," said Otis.
As the offspring of the French queen bees gradually take over the Ontario colonies which they're introduced to, they'll be monitored not only for mite infestations, but also for genetic traits that might affect their suitability and productivity in Ontario. "These experimental bees may display traits that Ontario beekeepers won't like," said Otis, who cautions that positive confirmation of mite resistance alone won't be sufficient to permit the French bees to leave the island. "If the imported bees prove to be resistant, the island could be turned into an isolated breeding colony where the French bees can be propagated or mated with Ontario queens to develop the natural resistance and eliminate any negative traits."
Otis hopes the island colony will produce queen bees that will be distributed to Ontario beekeepers for evaluation and subsequent breeding.
Prof. Gard Otis Department of Environmental Biology University of Guelph 519-824-4120, Ext. 2478