A number of factors, many manmade, have conspired to reduce the population of honeybees and other pollinators
July 2, 2014
Vaguely understood colony collapse disorder gets all the headlines, but here in southern New England, where commercial bees aren’t trucked in to pollinate acres and acres of almonds and apples, the biggest threat to the region’s honeybee population are a pair of tiny pests.
Varroa mites and tracheal mites, imported accidentally from Asia in the 1980s, attack honeybees in all stages of life, from larvae to adulthood, according to Rhode Island’s state apiary inspector.
“They feed on the blood of the bees,” said James Lawson, speaking about varroa mites, the most harmful pest to honeybees. These external parasites are just big enough to be seen with the naked eye, and look like mini-horseshoe crabs without the tail, he said.
When the mites suck blood, they leave wounds, where pathogens fester, said Rhode Island Beekeepers Association member Betty Mencucci. Infection kills many of a colony’s bees and eventually extinguishes the hive.
Microscopic tracheal mites clog the breathing tubes of adult bees, blocking oxygen flow and eventually suffocating them. Crawling bees outside of a hive unable to fly are likely suffering from acarine disease.
Ed Lafferty, president of the R.I. Beekeepers Association, said these pests, most notably the varroa mites, are killing feral colonies. “In the 1960s and ’70s we had a good population of bees in the wild,” he said. “You can still find them but they won’t persist. They have no staying power. The mites are wiping them out.”
Honeybees didn’t even exist in America until early European settlers introduced them. Native Americans, Lafferty said, called them the “white man’s fly.”
However, of the thousands of species worldwide, honeybees are hardly the only bees that provide pollination services free of charge — they just happen to be the most prolific because they exist in large colonies and can be easily managed.
Locally, for example, bumblebees, sweat bees and mason bees are just as capable, but do much of their work as solitary pollinators. In fact, bumblebees are such excellent pollinators that they are typically the bee of choice for pollinating greenhouses.
But, like the honeybee, the numbers of these pollinators are in decline, according to Mencucci.
“Native pollinators just aren’t around as much anymore,” the Rhode Island Bee School instructor said. “Their habitat is slowly being destroyed by parking lots and development, and from the mowing and plowing of fields.”
Natural pollinators, such as bees, birds, butterflies, beetles, bats and even the common housefly, are responsible for nearly a third of the food we eat. Pollinators transfer pollen and seeds from one flower to another, fertilizing the plant so it can grow and produce, say, watermelons or pumpkins. Without our winged friends, most notably honeybees, to spread seeds, many plants and some 100 key food crops would die off.
This essential relationship between people and pollinators makes the decline in their numbers, particularly those of honeybees, concerning. In the United States alone, more than 25 percent of the managed honeybee population has disappeared since 1990, according to the Natural Resources Defense Council (NRDC).
The world’s top pollinator is under attack on all fronts. Besides dealing with life-sucking parasites and the nasty pesticides specifically manufactured to kill them, many commercial honeybees spend the winter dining on high-fructose corn syrup — not on their own nutrient-rich honey.
Commercial beekeeping practices involve harvesting honey both in the fall and spring, which requires beekeepers to substitute sugary syrup for honey, the bee’s natural food source. It’s a practice that began in the 1970s.
If the cheap, government-subsidized corn syrup that fills soda cans and is the staple of processed junk food is good enough for humans, we may as well feed it to bees. But it’s not healthy for either of us.
Backyard beekeeper Chris Combs, founder of the organization Giving Bees A Chance!, said it doesn’t make sense to introduce an inferior substance to the hive. He describes this sugary corn syrup as the “bee equivalent to McDonald’s.”
“Bees thrive on their own high-quality, self-produced food, and having access to honey during the winter increases the well-being of the hive,” said Combs, who has been managing hives for the past eight years. “Bees live off pollen and honey, and a good, strong hive is resilient and can fight off disease. I take what I need. It’s their honey, not mine.”
The Blackstone, Mass., resident has six hives — one at his home, one at a friend’s house in Little Compton and four at Blackbird Farm in Smithfield. He harvests surplus honey available in the spring — about 100 pounds from each hive.
Combs’ concerns about fast food for bees is shared by some researchers. A team of entomologists from the University of Illinois has found a possible link between the practice of feeding commercial honeybees high-fructose corn syrup and the collapse of honeybee colonies.
The researchers haven’t suggested that this processed corn syrup is itself toxic to bees. They say their findings indicate that by eating this substitute instead of honey, bees aren’t being exposed to nutrients that help them fight off toxins, such as those found in pesticides.
When we’re not force-feeding the insects that pollinate a significant portion of the crops that feed us with empty calories, we’re spraying a pesticide that could be playing a major role in their declining health. Researchers have found that the widely used pesticide class called neonicotinoids act as a neurotoxin to bees and other insects.
This class of pesticide’s primary chemical can act like a nerve agent, compromising a bee’s ability to feed and make its way back to the hive. A French study has claimed that neonicotinoids can fog honeybee brains and alter behavior. A British study on bumblebees has reported that neonicotinoids keep the bees from supplying their hives with enough food for queen production.
Neonicotinoids, the most widely used insecticides in the world today, were introduced in the 1990s as a replacement for more damaging chemicals. While neonicotinoids don’t accumulate in human or animal tissue in the way that DDT once did, these modern pesticides are more lethal, about 6,000 times as toxic compared to the older spray, according to the International Union for Conservation of Nature.
And unlike traditional pesticides that are typically applied to the surface of plants, neonicotinoids are systemic — meaning they are absorbed and then spread throughout the entire plant, according to the Center for Food Safety (CFS). One way honeybees and other pollinators are exposed to these pesticides is through what they feed on — pollen and nectar.
Last June, in Oregon, after a landscaping company sprayed linden trees in a Target parking lot with a neonicotinoid to control aphids, some 50,000 bees died, according to the Oregon Department of Agriculture. Oregon has since suspended the use of two neonics linked to massive bee losses, and Eugene, Ore., has become the first U.S. city to ban the use of neonics on city property.
In Iowa, nearly 70 percent of the state’s bees were too sick — poisoned by toxic agricultural pesticides, according to the Sierra Club — to survive this past winter. Iowa beekeepers have called it one of the worst winters they have seen for honeybees.
Last December, the European Union began its two-year moratorium on three of the worst neonicotinoid pesticides to protect bees and other pollinators.
From blueberries to cucumbers, bees help produce more than 30 percent of the world’s food. In fact, according to Michigan State University researchers, bees are responsible for one out of every three bites of food we eat. The economic value of pollination services by bees is $365 billion annually and affects 50 percent to 80 percent of the world’s food supply, according to the researchers.
The Sierra Club calls the worldwide decline of honeybees a “catastrophe.” The organization has noted that U.S. beekeepers lost an average of 45 percent of their colonies between the end of 2012 and the end of 2013, and that, thanks in part to neonicotinoids, hives are producing 85 percent fewer queens.
In fact, concern about the decline of bee populations during the past decade, and its related impact on businesses and local economies, has grabbed the attention of the Obama administration. Late last month the president created a task force to study the problem.
In the memorandum announcing the Pollinator Health Task Force, Obama called on the participating scientists to develop a strategy within 180 day for addressing the decline of pollinators. The memorandum also specifically calls on the Environmental Protection Agency (EPA) to research the role neonicotinoids are playing.
More than a year before Obama’s June 24 announcement, in March 2013, CFS and a coalition of four beekeepers and five environmental and consumer groups filed a lawsuit against the EPA for its failure to protect pollinators from dangerous pesticides. The lawsuit is seeking the suspension of the neonicotinoids that have repeatedly been identified as highly toxic to honeybees.
Those concerned about the future of the world’s pollinators point to the rise of large-scale monoculture crops that decrease agricultural biodiversity and to the heavy use of pesticides.
“We’re still learning the problem of colony collapse disorder,” said Lawson, Rhode Island’s apiary inspector. “It’s a complex issue. There are many factors we just don’t understand yet. You can deal with mites by being vigilant, but I’m concerned for commercial bees.”
What triggers colony collapse?
U.S. beekeepers first noticed the problem in 2006: seemingly healthy bees were abandoning their hives en masse. The phenomenon was quickly dubbed colony collapse disorder. In the past eight years, nearly a third of all honeybee colonies in the United States have vanished, and the number of hives is at its lowest point in five decades, according to the NRDC.
Besides parasites, pathogens and the overuse of pesticides, there are a few other factors to consider when discussing what brought about colony collapse disorder, according to scientists and many beekeepers:
A warming climate is causing flowers to bloom earlier or later than usual. When pollinators come out of hibernation, some of the flowers that provide the food they need have already bloomed.
Habitat, such as grasslands, farmlands and shrublands, loss to development, growing crops without leaving habitat for native wildlife, and planting gardens with flowers that aren’t friendly to pollinators.
None of this bodes well for the complex organism that is a honeybee. If the lives of a hive’s honeybees are reduced by even just a few days, the colony won’t thrive or reach its potential. It will collapse.
Since 1947, the number of managed honeybee colonies in the United States has declined from 6 million to 2.5 million, according to a White House fact sheet. Given the heavy dependence of certain crops on commercial pollination, reduced honeybee populations pose a real threat to domestic agriculture, according to the Obama administration.
Honeybees are the most economically valuable pollinator in the world, and many high-value crops such as broccoli and almonds are entirely reliant upon pollination services by commercial beekeepers.
Commercial pollination is a big business, and it involves putting several million honeybees on a truck and criss-crossing the United States. It’s been estimated that the number of honeybee colonies rented annually for almond pollination ranges between 1.3 million and 1.5 million. The number of colonies rented annually for apple crop pollination is estimated to be more than 275,000.
It costs about $200 to rent a hive, according to Lafferty.
While this industry provides a vital service and helps keep America fed, there are some, such as Combs and Lafferty, who believe trucking bees around the country is a contributing factor to colony collapse disorder. Combs said the practice puts stress on a colony. Lafferty noted that the mixing of all these touring colonies has greater potential to spread parasites and disease.
“The business of beekeeping creates real problems. The bees aren’t properly cared for,” Combs said. “Colonies want to stay put, not shipped around the country. They’re feeding on almond pollen in California for a month, then it’s oranges in Florida and then blueberries in Maine. A healthy bee colony could live forever in a diversified habitat. But it’s cheaper and easier to truck bees in then it is to take care of them.”
To better protect the U.S. bee population, the NRDC says farmers must be rewarded for practices that help wild bee populations thrive, such as leaving habitat for bees in their surrounding fields, alternating crops so bees have food year-round and not using harmful pesticides. Assistance also should be provided to farmers who plan to support a wider variety of pollinators beyond just bees.
“Bees are hardy and will adapt — they’ve been surviving longer than we have — but we must do a better job caring for them by minimizing threats,” Combs said. “Honeybee hives are excellent indicators of what is good and bad in our environment.”