Ontario beekeepers estimate winter losses of 30 to 40 per cent

Friday, May 27, 2011

by SUSAN MANN

Ontario beekeepers’ winter mortality levels are similar to the losses of 30 per cent reported this week by American beekeepers.

And while researchers and beekeepers in both Canada and America say the number is still too high “the lack of increase in losses is marginally encouraging in the sense that the problem does not appear to be getting worse for honeybees and beekeepers,” says Jeff Pettis, United States Department of Agriculture (USDA) entomologist with the Agricultural Research Service.

But Pettis says on the USDA website that continued losses of this size puts tremendous pressure on the economic sustainability of commercial beekeeping.

The USDA released its losses from managed honey bee colonies report on its website May 23. For 2010/11, the USDA reports that total losses from managed honey bee colonies nationwide were 30 per cent from all causes. That’s similar to total losses in surveys done in the four previous years: 34 per cent in 2009/10; 29 per cent in 2008/09; 36 per cent in 2007/08; and 32 per cent in 2006/07.

John Van Alten, president of the Ontario Beekeepers’ Association, says not all of the surveys from Ontario beekeepers have been returned so exact numbers here aren’t known yet. But anecdotally Ontario’s winter mortality levels would be similar to the USDA numbers.

“We’re in that range of 30 to 40 per cent,” he says. There was small break from high winter losses last year “but we’re right back into it this spring.”

In his 2010 annual report released in November, provincial apiarist Paul Kozak said the average annual winter mortality last year in Ontario was 20 per cent. That level of colony mortality was lower than the previous three years, which was an average of 33 per cent for 2009, 2008 and 2007.
Even though the level of colony mortality in Ontario was lower in 2010 compared to the previous three years, Kozak says in his report that level is still higher than the 15 per cent threshold the extension and research community considers sustainable for maintaining a commercial beekeeping operation.

In the American survey done by the USDA and the Apiary Inspectors of America from October 2010 to April 2011, “beekeepers reported that, on average, losses of 13 per cent would be economically acceptable.” But 61 per cent of the 5,572 beekeepers who responded to the American survey reported having losses greater than 13 per cent.

Van Alten says Ontario’s beekeepers have become “fairly adept at replacing our losses either by splitting colonies or by purchasing queens from offshore or buying Ontario queens later in the season and making up nucleus colonies.” But “it’s really hard to grow an operation when you’re constantly looking at replacing high winter losses.”

Van Alten says he’s able to provide pollination services for all his regular customers. In general, most beekeepers will do their best to ensure their colonies are ready for those jobs.

The overriding cause of the high winter losses is the varroa mite, which “we still don’t have a really good handle on,” Van Alten says. “It’s really hard to control an insect on an insect.”

One thing that would help growers is a mortality insurance program for honey bees similar to crop insurance “so we can mitigate the economic shortfalls that we encounter when we have high losses,” he says. BF