By Linda Whitmore
Bees – whether commercially raised honeybees or native bumblebees – are vital for pollination of agricultural crops and backyard gardens. Today, bees’ existence is threatened across the country – but perhaps not so much in the Willamette Valley.
According to the Xerces Society, which keeps tabs on native bumblebees, a radical decline in wild bee population was recognized in late 2006, the same time the National Academy of Sciences reported seeing serious problems with honeybees.
The term “Colony Collapse Disorder,” or CCD was given to the recent honeybee decline. The problem is puzzling. Bees are abandoning their hives, leaving plenty of honey and pollen stored as food and deserting their capped brood cells. Unlike death from diseases, there are no dead bees in the hives. Bees have an incredible homing system. They travel to nectar and pollen sources, fly back to their hives and transmit directions to their hive-mates. With the CCD, the bees seem to fly out and never return.
Canby resident Chuck Sowers, president of Oregon’s Beekeepers Association, said in the Willamette Valley region CCD “hasn’t happened.” Sowers acknowledged “there has been a considerable amount of bee loss since 1986” (when varroa mites rampaged) but he said the loss has been less than in other regions and beekeepers have been able to rebound.
“Like any other type of farming, beekeeping has its ups and downs,” he said.
Sowers said although CCD has not plagued the Willamette Valley, there are fewer beehives available for orchards and fields. He said beekeeping in Oregon is an occupation largely managed by older men, and many of them are retiring.
“The number of beekeepers is way down, no doubt about that,” he said. Those remaining in the business have increased the number of their hives, “but it doesn’t make up the difference.”
In other parts of the country, Colony Collapse Disorder is the cause of the serious reduction in bee population. Several reasons for CCD have been suggested, some later rejected, and no definitive answer has been established. Proposed causes have been virus, mites, malnutrition, pesticides, stress due to long-distance transportation of hives and the feeding of high fructose corn syrup to supplement food supplies in winter. Some people have even claimed the cause was cell phones, jet contrails or wireless Internet, but studies have eliminated these as having a correlation.
In the late 1980s, the varroa mite was the most destructive threat to bees. Commercial beekeepers sought help from Oregon State University where researchers were able to develop an effective program of chemicals. The drawback is that the application process is somewhat complicated and doesn’t work well if not maintained properly. Another negative aspect was that wild bees were not included in the solution.
“Wild bees don’t get treated,” said Sowers.
It was thought about 90 percent of the nation’s wild bees have succumbed to the parasitic mite, and one species, Franklin’s bumblebee, is considered extinct.
Whether the varroa mite is part of the current decline is still being determined, but it is not the sole cause. Researchers are studying pesticides’ relation to CCD, but have found the task difficult because of the variety of chemicals applied in different parts of the country and the fact that professional beekeepers move their hives, exposing them to different pesticides.
One recently published report has found a link to nicotine-based pesticides. Another discovery is that the insecticide imidacloprid in sucrose solutions affects bee’s homing and foraging abilities.
One positive discovery is that organic beekeepers who do not use antibiotics or miticides are not being affected by CCD, even when the bees are located near affected bees.
Another factor attributed to CCD is climate change. According to the Xerces Society, “anecdotal evidence has suggested that some of the bumblebee species adapted to cooler temperatures are in decline.”
And bumblebees are also losing out to habitat destruction. Development of land for both agriculture and housing reduces wild bees’ food source. In California, where wild bees are important in pollinating watermelons, some farmers are encouraging them by leaving some land near the melon fields in a natural state and not spraying when their crops are in bloom.
In addition to melons, wild bees are considered better than commercial bees for pollinating blueberries, cranberries and peppers. They come out of their hives at cooler temperatures than honeybees.
Bumblebees perform “buzz pollination,” which “results in larger and more abundant” tomatoes, according to the National Academy of Sciences.
While it wouldn’t be expedient to have a beehive for pollinating the home garden, Sowers said, there are things one can to do avoid destruction of visiting bees, wild and commercial.
A gardener might plant flowers bees enjoy; bumblebees seem particularly fond of aster, clover, larkspur, lupine, mint, Oregon grape and rhododendron. Sowers said honeybees particularly like lavender and dandelions.
But the most important factor for bee preservation is the use of insecticides. Sowers suggests homeowners read labels carefully. Powdery products like Sevin are carried back to the hive where they can kill the colony.
“Read the labels – and don’t apply the insecticides when bees fly,” he said.
