Bees
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"Neonic" pesticides are killing bees, harming environment, say scientists. Read more: http://barrie.ctvnews.ca/neonic-pesticides-are-killing-bees-harming-environment-say-scientists-1.1886489
Pesticides, Not Mites, Cause Honeybee Colony Collapse. http://blogs.discovermagazine.com/d-brief/2014/05/09/pesticides-not-mites-cause-honeybee-colony-collapse/
New virus linked to bee colony collapse disorder. http://www.latimes.com/science/sciencenow/la-sci-sn-virus-bee-colony-collapse-20140120,0,3775756.story#ixzz2r53cmiq2
What Was Behind the Honey Bee Wipeout? Everyone has a theory why the honeybees started dying off. Try malnutrition. http://www.alternet.org/environment/65289/?page=1
Is a Virus Behind the Bee Plague? Scientists have identified a virus that might have triggered the problem. http://www.technologyreview.com/Biotech/19348/
Are the Bees Dying off Because They're Too Busy?
August 11, 2007 All across America, a mysterious disease is wiping out bee colonies. This malady causes all the bees in a hive to seemingly vanish overnight, abandoning their brood in the nursery, as well as their stores of honey and pollen. Other bees and pests, which normally plunder deserted honey, shun these hives. This baffling die-off dealt a financial blow to commercial beekeepers this season and raised fears of environmental and economic disaster. For farmers, no bees means no pollination.
But pollination is happening like mad in Leah Fortin's tiny yard in North Oakland, Calif. Busy little bee bodies cover the clumps of lavender, salvia and roses that line her driveway. More bees work the malaleucas on the parking strip, those trees with shaggy bark that look like giant Q-tips when they're in bloom.
A lot of these bees -- although surely not all -- come from the hive on Fortin's roof. The unobtrusive wooden box, barely 20 inches by 16, and 13 inches high, sits on the tar-and-gravel roof of her stucco bungalow, sheltered by the chimney. Honeybees bustle in and out of the narrow slit along the bottom, delivering bundles of pollen and droplets of nectar, then hurrying out again for more.
"The neighbors call us 'The Little House on the Prairie,'" Fortin said on a recent summer afternoon. "They think I'm a kook."
Fortin, who administers after-school programs, captured this wild swarm in early May, and so far it's thriving. "My book said to take two pieces of cardboard and scoop them into a five-gallon paint can, so that's what I did," she said. "I was scared shitless. I had no idea what I was doing." She covered the can with a net and drove home. "It worked, and there they are."
Fortin put out a small jar of honey to make the new colony feel at home; since then, she's done nothing except peek at them once in a while. "It doesn't matter what you know and what you don't know," she said. "The bees know what they're doing." And what they do is pollinate.
Honeybees aren't native to North America, so indigenous plants don't need them for pollination. If all the honeybees disappeared, we'd still have corn and wheat. But most of the imported fruit and vegetable species commonly thought of as quintessentially Californian -- almonds, grapes, plums, cucumbers, cantaloupe, asparagus -- need the help of bees to wed male pollen to female pistil. Without bees, there would be no apples, no cherries, no tomatoes, no zucchini. Even tofu would be scarcer -- soybeans depend partly on the honeybee for pollination.
Most of these crops are no longer pollinated by wild honeybees. Like many indigenous insects and plants, feral honeybees have been nearly wiped out by pesticides, loss of habitat and parasites like the varroa mite.
Meanwhile, commercial beekeeping has come to resemble other kinds of factory farming. While the bees themselves retain more freedom of movement than almost any other living creature raised by man, a commercial bee lot is more like a cattle feed lot than a wild meadow.
Beehives are crammed close together in rows just a few feet apart; in the wild, a square mile supports at the most three or four hives. A wild colony's diet is diverse, comprising pollen and nectar from myriad plants. To compensate for the lack of forage around bee lots, bees are typically fed high-fructose corn syrup, the same stuff that's contributing to a human health crisis. And just like other agricultural livestock, bees become stressed when you crowd them together. They're more susceptible to diseases and parasites, less able to function naturally.
It's all making some bee scientists wonder: Is the epidemic known as Colony Collapse Disorder real, or are the bees simply being worked to death?
Big beesness
If you want to put bees' value into dollars and cents, just look at California's almond industry. Almonds are the state's second-largest crop, with farmers raking in $2.34 billion in 2005. This year's yield, grown on 615,000 acres, is expected to be a record 1.310 billion pounds, up 18 percent from last year -- despite the dire statistics about Colony Collapse Disorder.
If you drive through the heart of California's agriculture industry, the Central Valley, watching the miles of orchards in bloom, they look natural. In fact, the California almond industry depends on a herculean human effort to subvert the natural order of things. In nature, most flowers don't get pollinated. But you don't get a billion-pound harvest by letting nature take its course. In the old days, an orchard owner might invite a beekeeper to keep hives on his land in a mutually beneficial arrangement. The agribusiness way is to rent hives for the two-week almond pollination season. This year, growers paid $150 per hive, placing three to five hives per acre.
Since 1999, beekeepers in the Pacific Northwest have earned four to five times more income from pollination than from the combined sales of honey and wax, according to a survey by Oregon State University.
But it was hairy out in the fields this year, as beekeepers from around the country raced to get their hives to California before they collapsed. Some growers found themselves renting empty hives.
Thousands of beekeepers had done the math and begun building up their stock. It's not uncommon for a commercial operation to run to 10,000 hives, trucking them from California to South Dakota to Florida in the course of a single year. One million hives, or nearly half of all the hives in the United States, were hauled into California this year, according to Randy Oliver, a beekeeper in Grass Valley, Calif., who has pollinated almonds for 25 years.
For a honeybee, the lucrative almond pollination season comes at the worst possible time. The natural lifecycle of a bee colony follows the seasons, with a hibernationlike rest period during the winter. Unfortunately for the bees, California almond trees bloom around Feb. 10, a miserably rainy time of year.
A colony may rear ten to 12 generations of bees in a year. The queen moves through the hive, laying eggs in combs toward the center of the nest. The eggs hatch in three days; the larvae are fed nectar by nurse bees until they emerge from their cells in 21 days to begin work in the hive. A few are male; they're called drones because they do nothing but hang around and eat, on call in case the queen dies and a new queen needs to mate. The females get to work, spending three weeks as house bees. They may feed the larvae, keep the hive clean, attend the queen or just fan their wings to cool the hive. Some act as sentries, attempting to chase away bears, skunks and robber bees from other hives. Then they go out to forage for another three weeks, completing their lifecycle. Elderly bees don't retire; they simply fly out one day and don't return.
As the days shorten and the sun dims, the hive produces its last generation of the year. These "winter bees" must survive the cold months and live long enough to raise the vigorous new brood that will bring back the spring pollen and begin the cycle again.
"Winter bees live for about six months," Oliver said. "Come spring, when the hives are moved to almonds, these same bees that survived the winter and raised the first brood then have to go out to forage. They can't do it." Instead of gathering the pollen, the exhausted bees drop dead outside the hive, Oliver surmises.
Eric Mussen, who specializes in beekeeping (an apiculturalist) for the University of California, Davis, thinks malnutrition could be another piece of the syndrome known as Colony Collapse Disorder -- the same kind of malnutrition afflicting Fast Food Nation.
Wild bees live on water, nectar, and pollen. Nectar provides the carbohydrates they use for energy and to make honey, while pollen is a rich mix of protein, fats, minerals, vitamins, and micronutrients. But just as human food can lose nutrients from overcooking, Mussen thinks adverse weather could produce tiny changes in pollen grains, resulting in one of the mysterious symptoms of Colony Collapse Disorder -- reports that the vanished bees leave behind combs rich with pollen. Too much chilling, as well as weather that's too hot and dry, can cause pollen to become sterile by killing its protoplasm. Perhaps, he speculates, bad weather destroyed some nutrients vital to the bees as well, making the pollen useless to their bodies.
The normal dearth of pollen in the fall, combined with the drought that swept the country last year, could have created a season's worth of undernourished bee colonies -- colonies too weak to stand up to the strain of life in the agrifactory.
"Perhaps bees in that malnourished state could have made it had they not been fed on by mites and viruses," Mussen says. Like humans, all bees carry viruses, but the immune systems of healthy bees usually keeps the viral load under control. "They haven't found a bee with less than two viruses. In some apparently healthy colonies, some bees had five to six different viruses. You can't blame the viruses, but if you have a weak bee, such things can overwhelm it."
Add this to the stress of days spent bumping over the interstates, and it wouldn't be surprising that colonies can't fight off the mites and viruses that plague them. A working bee's life has become as stressful as any human cube-dweller's. Colony Collapse Disorder, then, may be no more than the result of one too many things going wrong in a bad year, surmises bee broker Denise Qualls.
"Beekeepers, especially commercial beekeepers, have always lost 10 to 20 percent of their hives when they come out here for pollination," says Qualls, whose company, Pollination Connection, helps manage the annual rush of bees from all over the country that converge on California for the almond season. "Granted, the loss is higher, but -- you know, they used to just call it bad beekeeping. Now they have a name for it."
Buzz in the backyard
Qualls thinks inbred queens are another possible factor in collapsing colonies. The queen produces all the eggs to replace workers, and she secretes pheromones that keep the hive humming. The conventional wisdom is to purchase queens bred to be gentle and good honey producers; some beekeepers replace the queen each year, because a younger queen is supposed to be healthier. "But they keep coming from the same stock," Qualls points out, so any vulnerabilities may get reinforced.
Think of all the hereditary ailments that afflict purebred dogs, and compare that with the health of your basic mutt. Maybe these queens have become the poodles of the insect world. During last year's pollination rush, Qualls says, a significant number of queens died: "They just weren't strong enough."
Maybe that's what happened to Peter Scholz. For several years, he bought a starter package -- a queen and three pounds of bees -- and carefully placed them in the hive that sits on a four-foot-square perch under a tree in the backyard of his two-story Oakland Edwardian. All through the summer, they worked the flowers. But every winter, the colony dwindled away -- or, you could say, collapsed.
Scholz gave up, but left the hive in place. Two springs ago, a feral swarm moved in. This colony is thriving, and he expects to get 50 pounds of honey this year. "It makes sense in a Darwinian way that the hives that flourish locally and swarm are the ones you want to adopt," he says.
It's a method that's worked for commercial beekeeper Steve Gentry for nearly 30 years. He keeps around a hundred hives scattered in 14 locations from here to Santa Cruz; in winter, he takes them all to the Santa Cruz Mountains to get fat on the manzanita bloom. Every colony originated from a wild swarm.
"All my hives are survivor stock," he says, ones that have managed to fight off varroa and tracheal mites, two parasites that began infecting American colonies in the 1990s. "It's survival of the fittest. If my bees swarm, there's some vitality there. Beekeepers say they don't have time for swarms. But when they don't have any bees, they'll have time."
Living among the bees
Swarming is the natural process by which a colony reproduces itself. Capturing swarms is a popular pastime for backyard beekeepers -- and it may provide insurance against whatever disasters are befalling commercial operators. A colony has to be strong, healthy and able to fight off disease in order to expend precious resources in swarming. The swarm is a group of hardy pioneers led by a queen who has proven herself through breeding and, perhaps, in combat with another queen.
In the spring, while the hive is buzzing with newborn bees and the combs drip with honey, the colony produces a second queen. The old queen flies out with a batch of drones to mate, and then takes off with a thousand or so workers to find a new home. The swarm pauses to rest and feed, gathering en masse on a tree limb or wall, while scouts look around for an attractive site. They may stay for a day or two and then move on if they don't find a good spot.
So, when Leah Fortin gets another swarm call on a hot June weekend, she throws her gear in her truck and, with neighbor and fellow beekeeper Peter Scholz, goes after it. But this mass of bees on a clump of lilies in the front yard of a house near Grizzly Peak is no longer a swarm; it's begun to set up housekeeping on several fronds of the plant. They must have been desperate; worker bees in a swarm have only three weeks to establish a new colony, lay down comb, and let the queen begin to lay eggs before they die. When it gets close to their time, they'll build comb on just about anything. But there's no way this nascent colony could have survived the winter's cold and wind.
Fortin uses a special smoker to calm the bees -- this is a standard practice, although no one knows exactly why it works. She grasps the bundle of leaves clotted with wax and snips them off. Now she has a bee bouquet. She gently places it in a five-gallon bucket.
Back at Scholz's house, it takes only minutes to put the bees into their new home. A standard beehive consists of a wooden box with a separate bottom and a lid that rests on top. Inside the box, nine or ten wooden frames hang from a ledge, like folders in a file cabinet. Each frame holds a sheet of foundation on which the bees will build their hexagonal chambers to hold eggs, developing larvae, pollen and honey.
Bees generally fly as far as four miles in search of food, but they do best when they don't have to venture more than half a mile. Pickings should be good in this heavily planted neighborhood, even though there are at least three other tame hives and one wild colony nearby.
While Fortin's North Oakland neighborhood is teeming with bees, others may have none.
The yield from Bill Smith's home orchard in the Alameda County town of Hayward, Calif., doubled after he installed his first hive five years ago. It all started with the 4-H Club. Another member had a hive near horse stables and mischievous boys, a bad combination. Smith agreed to take them: "I noticed that the following year, we got a much better fruit set around here. We really were starving for bees."
Smith claims he keeps bees only for pollination. But now there are the ten hives piled on a small trailer in a corner of his hilltop half-acre, plus a tottering stack of empty hive boxes waiting for new colonies. He is president of the Alameda County Beekeepers Association, and he's stockpiling honey to make mead. It's a sure case of bee fever.
The engineer lives with his family in a century-old house on a former chicken ranch. You can see the successive waves of development. A few two-acre pastures still dot the hill, surrounded by 1950s ranch houses. Lately, some of those pastures have been replaced by stucco mini-mansions that fill almost the entire lot.
"Don't tell the neighbors I'm here," Smith says. "They don't know." The row of yards bordering his are downhill enough that the honeysuckle-covered fence between them completely obscures their view. To the north, the hives are shielded by a thick cedar tree, and the house and garage obscure the view from the street and the south side.
Like Fortin, Smith is a laid-back beekeeper. "I hardly ever work the bees," he says. "Bees know how to take care of themselves. You give them a place to live, and they go crazy on their own."
Indeed, bees follow an internal timetable that's been bred into them through eons. Home beekeepers know that the less you try to do for the bees, the healthier they'll be. Is it some pheromone the bees put out that places you in their thrall? Or just that they're so fascinating, so soothing to watch? In any case, Smith is far from the first person to find that one hive leads to another.
"I hear about a good deal, or someone calls me up and says, 'I just captured some bees, and I have nowhere to put them.' I guess I'm just greedy," he says.
Back to nature
Although Steve Gentry says bees are a sideline for him, it's a pretty robust sideline. Gentry sells 3,000 to 4,000 pounds of Steve's Bees-branded honey every year at gourmet groceries and natural-foods stores, all small-run varietals. Right now, he's featuring chamise honey, made from the nectar of the tough, white-flowered chaparral bush. He has another lucrative business removing hives from inside the walls of homes.
While commercial beekeeping has become a high-labor, low-margin line of work, in the backyard it can be as natural and laissez-faire as you please. If you get a couple of quarts of honey, it's all good. But there is a middle ground, and people like Gentry are moving there. They're taking some tips from the Slow Food movement, offering high-quality, locally produced products at premium prices.
Marshall's Farm Honey, based in American Canyon in Napa County, is credited with being among the first companies to take honey upscale. Spencer and Helene Marshall have taken their cues from the winemakers of Sonoma County, offering small batches of varietal honey at farmers' markets. They scatter a few hives at choice locations throughout the Bay Area and isolate batches produced by the sequential wildflower and tree blooms. They encourage consumers to appreciate the "special flavor nuances and wonderful color variations" that result. The Marshalls even offer Hood Honey, described as a middle-range amber village mix, harvested from Oakland's neighborhoods.
Honey is just one product of those highly productive bees; the pollen and wax they produce are valuable, too. Exploiting them -- making use of everything possible -- is another lesson from boutique farmers.
For instance, you'd never know it from Judy Casale's house in an upscale subdivision in Castro Valley in California's Alameda County, but she whips up batches of lip balm, soap, lotion, candles and specialty honeys in her Tuscan-style kitchen. There's even one hive in her lushly landscaped backyard; her remaining stock of 34 hives is dispersed on private property throughout the Alameda County areas of Livermore and Castro Valley.
Like a lot of beekeepers, Casale got interested by chance ten years ago, after a presentation at a meeting of the California Rare Fruit Growers. "I liked the idea of backyard honey and pollination," she recalls. "I wasn't crazy about handling bees, but I got over it. The first time I poured a container of bees into a hive was pretty scary." She still completely suits up when she works the bees in her backyard, a colony with a cranky temperament.
She branched out from selling honey seven years ago. "There are only so many candles you can make, use, and sell, and I was looking for something more creative," she says. Today, her Dominique skincare line is a thriving operation that's transitioning from a hobby to a sideline business. Casale has landed accounts at several Los Angeles spas and is looking for more in the Bay Area. Her latest concoction is mojito-flavored lip balm.
Randy Oliver, the Grass Valley beekeeper, is another who looks beyond honey and wax. In fact, he looks to exploit every niche he can find. In addition to managing and renting 500 hives, he raises and sells queens and starter colonies in the spring. He teaches apiculture to bee clubs and schools, and he writes articles for journals. He's even getting into Web media, charging a small subscription fee for his website content.
Oliver wants to help commercial beekeepers get off the slippery slope of using more and more chemicals that have less and less of an effect. His 500 hives are small-time by commercial standards, but enough to prove the effectiveness of a more natural approach. He aims to be a bridge between agribusiness bees and the backyard.
Big operations have become monocultures, making more money from pollination than from honey -- and sometimes even killing off bees at the end of the season. Instead, Oliver advocates integrated pest-management strategies that keep mite populations down to reasonable levels without pesticides. At the same time, he acknowledges the professional's need to automate and minimize labor.
For example, dusting bees with powdered sugar causes varroa mites to fall off them. If you also replace the solid bottom of the hive with a screened bottom, the mites fall all the way out and have trouble crawling back in. But sprinkling powdered sugar is a lot slower than fumigating a hive, so Oliver invented a brush/cup combo that lets a beekeeper powder down a hive in just 15 seconds.
"Beekeepers, like most agriculturists, are pretty conservative and not willing to risk their operations by trying something out," he says. "They want to see other beekeepers doing something successfully and making money doing it. If they see people making money, they'll change."
http://www.alternet.org/environment/59426/
Scientists examine cause of bee die-off
- healthy bees
- David Hackenberg, owner of Hackenberg Apiaries, holds a frame which he pulled from one of his hives as he points out newly-born honeybees at his farm's hive storage area in Lewisburg, Pa., Tuesday, June 12, 2007. Scientists investigating a mysterious ailment that killed many of the nation's honeybees are concentrating on pesticides and a new pathogen as possible culprits, and some beekeepers are already trying to keep their colonies away from pesticide-exposed fields (AP Photo/Jimmy May)
LEWISBURG, Pa. -- Scientists investigating a mysterious ailment that killed many of the nation's honeybees are concentrating on pesticides and a new pathogen as possible culprits, and some beekeepers are already trying to keep their colonies away from pesticide-exposed fields.
After months of study, researchers are finding it difficult to tie the die-off to any single factor, said Maryann Frazier, a senior extension associate in Penn State University's entomology department.
"Two things right now ... that are really keeping us focused are the pathogen and the role of pesticides," Frazier said.
Scientists from Penn State and the U.S. Department of Agriculture are leading the research into colony-collapse disorder, including study of the yet-to-be identified pathogen, a microorganism capable of causing disease.
But commercial beekeeper David Hackenberg isn't waiting to take action. He's asking growers whether they use pesticides on fields before bringing his bees for pollination.
Honeybees don't just make honey; they pollinate more than 90 tasty flowering crops, including apples, nuts and citrus fruit.
Hackenberg, 58, trucks his bees around the country for pollination - from oranges in Florida to blueberries in Maine. He was the first beekeeper to report the disorder to Penn State researchers last fall, having lost nearly 75 percent of his 3,200 colonies.
He said he is convinced pesticides, and in particular a kind of pesticide called neonicotinoids, were harming his bees.
"I'm quizzing every farmer around," Hackenberg said. "If you're going to use that stuff, then you're going to have go to somebody else."
The beekeeper of 45 years is back up 2,400 colonies and doesn't want to lose his bees again.
He and his son, Davey Hackenberg, who operate Hackenberg Apiaries, are considering raising prices to cover the cost of replacing hives that may die off because of colony collapse. They charge about $90 a hive now to "lease" their bees in fields; it costs $120 to replace a hive with new bees, the Hackenbergs said.
Beekeeper Jim Aucker, of Millville, was left with just 240 of his 1,200 hives earlier this spring after the illness struck. He said he's back up to just under 600 now. He is convinced pesticides are playing a role.
"I have found spray materials in our dead hives. Whether it's 100 percent the cause, I'm not sure, but I'm positive it's not helping," Aucker said. He doesn't plan to return to fields where he thinks there might be a pesticide problem.
Daniel Weaver, president of the American Beekeeping Federation, said he wasn't surprised some beekeepers were staying away from fields with insecticides.
"I try to limit my association to growers that I know will be responsible bending over backward and to go out of their way to avoid pesticide application while the bees are flying," he said of his own colonies. "Of course, I can't escape it completely."
He also cautioned what other scientists have echoed - that bees' immune systems might be weakened and vulnerable for reasons besides pathogens and pesticides, such as mites.
Bayer Crop Science is one of the top producers of the neonicotinoid pesticides in the country, and the product has been on the market since 1994.
"We have done a significant amount of research on our products, and we are comfortable this it is not the cause," said company spokesman John Boyne, an entomologist by training.
"The current research indicates that a number of nonchemical causes may be to blame," Boyne said when asked beekeepers' concerns regarding pesticides. Bayer is cooperating with federal and university scientists.
Some of the neonicotinic pesticides are available in stores to homeowners, though some bottles may not have the same warning labels as those available commercially, researchers and beekeepers said. Bayer officials said they were not aware of the issue but were looking into it.
Some beekeepers worry fruit and vegetable growers may be spraying pesticides in ways other than the directions on labels, said University of Montana bee expert Jerry Bromenshenk. His survey of beekeepers found instances of colony collapse in about 35 states.
Reports are across the board as of mid-June, a time when bee colonies are supposed to be thriving. Some beekeepers have said they are losing bees, while others are holding steady or growing colonies again.
Hackenberg said he went to the extreme of trying to disinfect many of his hives with radiation.
But he fears what might happen if his bees get struck again. A call came in on his cell phone as he worked with a thriving hive of honeybees on a hill above his house - a caller was trying to line up bees for 2008.
"Yeah, we sell bees," Hackenberg said, "if we're still in business next year."
Mid-Atlantic Apiculture: http://maarec.cas.psu.edu/
http://seattlepi.nwsource.com/national/1501AP_Dying_Bees.html
Beekeepers here and nationwide worried about unexplained deaths
May 16, 2007 Mike Rueden of rural Seymour keeps bees to sell the honey.
When he went to check on his 80 hives this spring he found only 15 colonies had survived. The bees apparently had succumbed to the mystery disease that is affecting bees nationwide.
It’s not just Reuden’s bees. Another beekeeper, Bob Bennett of Greenville said he was wiped out, too.
“I had 45 colonies last year and had only two left this spring,” said Bennett. “Then the queens in those died and I bought more queens and they died in just the past two weeks.”
Now a nationwide investigation, congressional panels and a recent U.S. Department of Agriculture scientific workshop are swarming around the newly named “colony collapse disorder.” Says the USDA’s Kevin Hackett, “With more dead and weakened colonies, the odds are building up for real problems.”
“We lost 75 percent of our bees,” said Rueden who now is carefully nursing 14 hives in the hopes that he can salvage enough honey to get through the season.
Beekeepers report losses of 30 percent to 90 percent of their honeybee hives, according to a Congressional Research Service study in March. Some report total losses.
Rueden speculates that perhaps genetically altered crops are the culprit, crops that have little nutritional value in their pollen. But that is just a guess.
Bennett also blames pesticides for the losses.
“There is no doubt in my mind and just wait until after June 15 when the pesticide applications start,” he said. “They are getting pollen that is killing the bees.”
Rueden is making plans to try to prevent the severe losses of last winter.
“We are going to try some new things and do some divides and try to winter smaller numbers of bees in smaller hives,” he said.
New type of disorder
The $15-billion-a-year honeybee industry is about more than honey: The nimble insects pollinate 90 percent to 100 percent of at least 19 kinds of fruits, vegetables and nuts nationwide, from almonds and apples to onions and broccoli.
“Basically, everything fun and nutritious on your table — fruits, nuts, berries, everything but the grains — require bee pollinators,” Hackett says.
Beekeepers, who travel nationwide supplying pollinators to farmers, have been losing honeybees for a long time, mostly a result of suburbs snapping up habitat and the invasion in the 1980s of two foreign parasitic mite species.
As a result, bee colonies have declined 60 percent since 1947, from an estimated 5.9 million to 2.4 million, says entomologist May Berenbaum of the University of Illinois.
Each year, in fact, the bee industry supplies at least 1 million queens and packages of bees to replace lost hives, according to a 2006 National Research Council report. And sudden losses of hives have been reported since the 1800s.
But colony collapse disorder differs from past outbreaks:
- Instead of dying in place, the bees abandon the hives, leaving behind the queen and young bees.
- Remaining bees eat sparsely and suffer the symptoms — high levels of bacteria, viruses and fungi in the guts — seen by Hackenberg.
- Collapses can occur within two days, Hackett says.
- Parasites wait unusually long to invade abandoned hives.
Daniel Weaver, head of the 1,500-member American Beekeeping Federation, estimates that about 600,000 of 2 million hives (a more conservative number than other estimates) nationwide have been lost.
A colony collapse disorder working group based at Pennsylvania State University has become a central clearinghouse for all the suspected causes, which include:
- An overload of parasites, such as bloodsucking varroa mites, that have ravaged bees. The parasites reportedly spread to Hawaii only last week.
- Pesticide contamination. Hotly debated suspicion centers on whether “neonicotinoid” insecticides interfere with the foraging behavior of bees, leading them to abandon their hives.
- Fungal diseases such as Nosema ceranae, which is blamed for big bee losses in Spain. It was spotted by University of California-San Francisco researchers who were examining sample dead bees in late April.
- The rigors of traveling in trucks from crop to crop.
A complex problem
We may have a perfect storm of many problems combining to kill the bees,” Hackett says. And bees are social animals, which cue each other through “bee dances” to find food. “Something could be just disrupting bee society and causing the problem. That’s very difficult to tease out.”
Weaver says the beekeeper federation is “bombarded with lots of interesting theories,” including “far-fetched ideas like cell phones,” the notion that radio waves from mobile phones are zapping the bees’ direction-sensing abilities.
“But right now there’s not a lot of evidence to support any of these theories,” Weaver says. “We think science is the only way to get to the bottom of this.”
The USDA spends about $9 million a year on bee research, Hackett says, about half of it focused on breeding bees resistant to mites. California is undertaking a five-year, $5 million project to examine insecticides, hive care and transport as well, he says.
Weaver says researchers need perhaps $50 million over the next five years to cover studies, deeper analysis of the “leading suspects” and a national surveillance system.
“Creating healthier bees, with a good diet, better able to fight disease is the best thing we can do right now,” Hackett says. Otherwise, “when you sit down to dinner, the question will be what sort of grain do you want — corn or wheat or rice — because that’s about all the choice we’ll have left.”
http://www.postcrescent.com/apps/pbcs.dll/article?AID=/20070516/APC0101/70516100
