An unprecedented die-off of commercial honeybees on southern Vancouver Island this winter has left beekeepers in the region scrambling to rebuild their devastated stocks in time for spring.
"It's really bad between Nanaimo and Victoria. We're talking in the vicinity of about 90-per-cent losses," said Stan Reist, president of the B.C. Honey Producers Association. "It's hit most of the commercial guys pretty hard."
While many beekeepers blame the high mortality rate on the varroa mite, a parasite that began afflicting the Vancouver Island bee population around 1997, Mr. Reist said researchers have yet to confirm the exact cause of this winter's population collapse.
"The samples have been taken, they're going in for testing, but we still don't have a valid reason for what's going on," said Mr. Reist, who owns the Flying Dutchman apiary in Nanaimo.
Vancouver Island's bee population was also hit hard in 2007, when between 55 and 65 per cent of hives perished. Over the last three years, the number of commercial colonies on the island has dropped to 2,000 from about 12,000.
It's become a familiar story: In 2006, an alarming spike in the number of disappearing bee colonies across North America prompted experts to coin the term "colony collapse disorder," a phenomenon that has since been identified in more than half- a-dozen European countries.
Research into the exact causes of colony collapse disorder has generated much academic debate. In Ontario, biologist Ernesto Guzman at the University of Guelph studied more than 400 colonies throughout three seasons and found that varroa mites were associated with more than 85 per cent of colony deaths. The next most important causes of death, Prof. Guzman said, were too-sparse beehive populations in fall and insufficient food reserves for winter. "We're pretty sure we've solved a great deal of the mystery," he said.
Under a quarantine put in place in the mid-1990s, Vancouver Island beekeepers are prohibited from bringing in replacement bees from the North American mainland, a restriction that has forced island breeders and honey producers to import hives from the southern hemisphere.
At 2:30 a.m. on Monday, Mr. Reist and a colleague picked up 637 packages of New Zealand bees at the Seaspan dock in Nanaimo and spent the next eight hours delivering the live cargo to various apiaries on the south island. Mr. Reist has another 420 hives on order from Chile, but the shipment's arrival has been cast in doubt by the recent earthquake. "We're just trying to get the job done," he said. "We've got a lot of people waiting and we don't know what's happening with Chile ... When it rains, it pours."
Central Saanich bee breeder Grant Stringer purchased 200 boxes of New Zealand bees from Mr. Reist that he plans to resell to honey producers in the region.
"I can expand these colonies and sell them to the people who got wiped out," said Mr. Stringer, who spent all day Tuesday transferring lunch-box-sized cartons of bees into starter hives called nukes. "This is the first (time) in 10 years I've had to import bees," he said, adding that a full shipment of 760 boxes costs about $80,000.
Part of the challenge for beekeepers is that the mites have developed a resistance to pesticides. Mr. Stringer limited his losses to about 30 per cent last season by using organic acids to battle mite infestations, but said the treatment must be applied in early August, when honey producers like to keep their hives in mountain meadows and other nectar-rich locations to maximize production.
Sol Nowitz, owner of Jinglepot Apiaries in Nanaimo, said bees imported from the southern hemisphere lack the genetic resistance to cold and disease they need for long-term survival in Canada. Mr. Nowitz, who has lost close to 260 of his 275 hives since 2007, called on the province to allow island apiaries to import "breeder queens" from elsewhere in Canada.
Island bee colonies have also suffered in recent years from cold, wet winters that weaken the bees' resistance to disease, and hot dry summers that limit the amount of nectar blossoms can produce, Mr. Nowitz said. "If there's not a lot of nectar coming in, the queens cut back on their egg-laying because they know they can't feed a large colony," he said.