COLUMBUS, Ohio -- Honeybees in the wild in North America have been virtually wiped out by an unusually harsh winter, a soggy spring and two blood-sucking mites, an Ohio State University bee expert says.
"Honeybees in the wild are decimated," said James E. Tew, an associate professor of entomology at Ohio State and honeybee researcher with the Ohio Agricultural Research and Development Center (OARDC) in Wooster, Ohio. Bee experts across the country agree that most of the wild or feral honeybees have likely been annihilated, Tew said.
Backyard gardeners will feel the impact in smaller yields and smaller, lower-quality fruits and vegetables, according to Tew.
"The harsh winter across the United States and the wet, messy spring, combined with all the routine problems facing bees that have never gone away -- bee diseases, pesticide problems -- pushed honeybees to the edge," Tew said. "The mites, however,were clearly and definitively the last straw in causing this population collapse."
Honeybee populations maintained by the nation's beekeepers have also been reduced by mites, Tew said, although not as severely. Estimates of domesticated bee losses to mites vary from state to state, he said.
"Honeybees are not in danger of extinction. Beekeepers are still maintaining around 3 million colonies in the United States," Tew said. "What's much closer to extinction, however, is the unmanaged population of honeybees."
The European honeybee, which was brought to the United States in the 1600s, is the country's most important bee for crop pollination and honey production, Tew said. According to the OhioDepartment of Agriculture, more than 90 American crops valued at more than $9 billion depend on bees for pollination.
The two mighty mite culprits -- the microscopic tracheal mite and the larger varroa mite -- are invader species that made their way into the United States in the mid- to late '80s. Tracheal mites do their damage by infesting the breathing tubes of the honeybee, puncturing the tracheal wall and sucking the bee's blood. Varroa mites, on the other hand, attach themselves to the outside of both honeybees and their developing young to perform their blood-sucking duties. The two mites also often carry invading viruses. Tracheal and varroa mites spread when infested bees come in contact with bees from other hives or when uninfested bees raid the hives of weakened, infested bees, Tew said.
"These mites decrease the honeybee lifespan to almost nothing," he said. "Many bees never emerge. When they do emerge, 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.
"If there had been tracheal mites only, there's a good chance the wild honeybee populations could have recovered fairly quickly. But with the combined effects of the tracheal mites and varroa mites, it became too much of a challenge for bee populations to maintain themselves."
Small and medium-sized fruit and vegetable growers and backyard gardeners will likely be hardest hit by the wild honeybee blight, Tew said.
"The decimation of honeybees in the wild means that honeybees are now a scarce commodity," he said. "Large professional growers can still rent colonies of bees for crop pollination and have them trucked long distances. It's small and mid-sized growers who are going to feel the pinch first. They're going to have difficulty competing with large growers for scarce honeybee colonies."
These small and medium-sized growers are also likely to lose out to a safer and more lucrative activity for beekeepers, Tew said -- honey production.
"The price of honey has doubled in the last 18 months," he said. "In many cases, honeybees will be redirected into honey production rather than crop pollination. It's a less risky business decision for the beekeeper."
Backyard gardeners will notice the effects of the honeybee blight in smaller yields and smaller, lower quality fruits and vegetables, Tew said. The lower the number of a plant's seeds "set" by pollination, the lower the quality of the fruit, he said. In fruit, apple, cherry, crab apple, plum and pear trees will be dramatically affected, he said. In vegetables, cucumbers, cantaloupes, watermelons, pumpkins, and squash will be hardest hit.
At the same time, consumers will notice the effects of the honeybee decimation in higher fruit and vegetable prices at supermarkets and farm stands.
Other insect pollinators, such as bumblebees and other wild bees, will step in for the absent feral honeybees and pick up a portion of their pollination duties, Tew said. However, he said, culturing bumblebees or wild bees in great numbers or importing foreign bees are not easy solutions to the honeybee shortage.
"A honeybee is a generalist. It does a good job pollinating apples or cucumbers," he said "Other types of bees are very specific to certain crops.
"Plus, if we take native wild bees and culture them, we're going to generate new problems there, too. If we bring together 10 to 20 times the number of bees that were ever together before, we could expect to have disease outbreaks and other challenges occur. We can't just whimsically switch to different bees and have that solve all the problems."