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Wild Honeybees, Nature’s Pollinators, Are in Trouble, Victims of Manmade Pollution and Tiny, Destructive Mites
Bee populations aren’t what they used to be. Experts estimate that more than 90 percent of wild honeybee colonies in North America have been wiped out over the last decade, casualties of a harsh winter, a wet spring, overuse of pesticides and attacks by two pernicious varieties of blood-sucking mites.
Imported from Europe in the 1600s and successfully established in the wild throughout the Americas, honeybees have played an important agricultural role, pollinating some 90 different crops in the U.S., valued at more than $9 billion per year. “Honeybees are not in danger of extinction,” says James F. Tew, an associate professor of entomology at Ohio State University and a honeybee researcher. “Beekeepers are still maintaining around three million colonies in the U.S. What’s much closer to extinction, however, is the wild population of honeybees. Pesticides have been a factor, but the mites were clearly and definitively the last straw in causing this population collapse.”
The smaller of the two guilty mite species is a microscopic tracheal mite that lives in the breathing tubes of adult honeybees and sucks their blood, causing adult bees to become disoriented and weak, and causing colony populations to dwindle. Beekeepers have been fighting the tracheal mite, itself a stowaway from Europe, since the 1920s with legislation restricting importation of honeybees, but the mite has slowly worked its way north from Mexico in recent decades, and is now seriously threatening bee populations in the U.S. According to Tew, two materials-specially prepared vegetable shortening “patties” and menthol-are useful in temporarily suppressing the tracheal mite infestations in domesticated bee colonies.
The other mite, called the varroa mite, has spread in recent years from Asia to virtually the rest of the world. The varroa is an external parasite, about the size of a pinhead. It attacks bees at their pupae, larvae and adult stages, causing deformities and injuries, essentially killing all colonies it infests. “These mites decrease the honeybee lifespan to almost nothing,” says Tew. “They’re so weakened or deformed that they’re nonfunctional. They don’t contribute to the output of the colony, and the whole population crashes and dies,” he says. Some insecticidal controls are effective against the varroa mite, but eradication of either mite is highly unlikely in the foreseeable future.
Beekeeper Vincent Kay of New Haven, Connecticut says that bee mites “changed my whole life. Starting around eight years ago, it began to take a huge chunk of profit out of the industry; its become incredibly labor-intensive.” Kay says he spent $4,500 last winter on menthol crystals (for the tracheal mite) and Apistan strips (for the varroa mite). “That combined with the expanding use of backyard pesticides, and the severe winter we had last year makes a real formula for disaster,” says Kay. “And it’s important because of honeybees’ role in crop pollination.”
Kay, who maintains 350 colonies, with 60,000 to 100,000 bees in each, says he is now one of only two commercial beekeepers left in Connecticut. He’s had to raise prices on his Swords Into Plowshares Honey 15 cents per pound in the last six months. “Unless someone starts making some progress researching bee genetics, I’m pretty discouraged,” Kay says.
Professional growers are turning to renting bee colonies and having them trucked long distances to ensure crop pollination. Small-scale farmers and backyard gardeners in particular may see smaller yields and smaller, lower-quality fruits and vegetables as a result of the decimation of wild honeybees. Other pollinators, including other bees, hummingbirds and butterflies, may pick up some of the slack in performing pollination duties, but Tew cautions against thinking of them as the ultimate solution to the honeybee crisis. “A honeybee is a generalist; other types of bees are specific to certain crops,” he says. “We can’t just whimsically switch to different bees and have that solve all the problems.”
Disputing that contention, however, is Dr. Leonard Feldman of the house and garden supplier Whatever Works, which is promoting native Orchard Mason bees as a pollinator alternative. “In addition to being effective pollinators,” Feldman says, “they require minimal attention.” And, he adds, they’re not affected by mites.
In early October, Florida’s NVID International said that it is testing an environmentally safe liquid disinfectant, Microsafe F-5A, as a bee protectant. “All of our initial studies give us a very high level of confidence that we will be able to kill the fungi and mites without harming the bees or plants,” says NVID President Bob Bunte.
In their recent book The Forgotten Pollinators, entomologists Stephen Buchanan and Gary Paul Nabhan advocate creation of insect preserves, modification of pesticide application practices, and exploration of alternatives to the honeybee for specific crops. “We can no longer afford to risk the security of our food supply on the services of just one insect,” says Buchanan.