In the winter of 2006, bees began to die by the millions. European honey bees – the pollinating insects responsible for $15 billion worth of crops in our country each year – were gone. Commercial hives were empty except for perhaps a live queen and a little honey. Because the bees died outside the hive, they were difficult to study. Scientists, beekeepers and food lovers were alarmed.
Our increased understanding of the phenomenon known as Colony Collapse Disorder (CCD) in the years since, and the difference between Willamette Valley losses and those of the rest of the U.S., suggest both the basic cause of the problem and what steps we can take to remedy it.
As long as humans have managed honey bee hives, they’ve seen the creatures die back in the winter, but losses since 2006 were of a whole new magnitude. While historical shrinkage was 10-15% per winter, the American Bee Journal estimates the 2006 shrinkage at 45%. Dr. Ramesh Sagili, assistant professor of Horticulture at OSU Corvallis, tells Salem Weekly that the following winter of 2007, colony losses were 35.8%. 2008 had losses of 29% and in the winter of 2009 they were 34%.
“These unusually high numbers,” Dr. Sagili says, “are a huge threat for the beekeeping and agricultural industries.”
European honey bees are not native to North America but were brought over by settlers in the 1700s. They are used to pollinate an abundance of crops on which we rely: soybeans, apples, cantaloupes, cucumbers, watermelon, strawberries, blackberries, onions, pumpkins, avocados and carrots. In fact, fully one-third of crops central to our diet are only possible because of commercial honey bees.
The percentage may get even larger. A study conducted by the United Nations, published in Current Biology in 2009, found that there has been a more than 300% increase in worldwide agriculture that depends on bee pollination in the last fifty years.
The potential for a food disaster resulting from CCD is the main reason the USDA allocated $20 million for a 5-year investigation into it in 2008.
Scientists around the world have found the following:
- The introduced Varroa mite carries viruses that attack honey bees
- Insecticides, for obvious reasons, kill honey bees
- Some genetically modified crops actually produce a natural insecticide (Bt toxin) that may affect honey bees
- Bee rental and travel (local bees are trucked to California to pollinate almonds through many ag lands with numerous chemicals involved), causes stress
- Malnutrition more frequently befalls honey bees because they must forage on mono culture crops, which lack all the amino acids, vitamins and minerals they need
- Malnutrition is increasingly caused by the use of high-fructose corn syrup to feed overwintering honey bees. Some researchers are also concerned by the higher use of genetically modified corn to make this syrup.
All researchers believe that there is not one single cause but a combination of factors that result in CCD. But the unifying factor is modern agricultural practices. This includes our increasingly monocultural crop plantings, which denude the ground of competing and alternate sources of pollen for honey bees. It also includes the increase of pesticides, which cost the United States $4.3 billion dollars in 2007, kill bees that stray onto crops adjacent to the ones they are targeted to pollinate, and insinuates itself into streams and soil.
Viruses blamed most frequently for CCD wouldn’t cause the number of deaths if it weren’t for what Dr. Sagili causes the “perfect storm” of environmental factors. “Viruses like that from the Verroa mite usually don’t kill bees. We’re seeing it now because of the new stresses honey bees face. They just can’t keep up.”
Sagili works with Dr. Dewey Caron, retired professor of Entomology from Cornell who now lives in Portland. “The nature of the epidemic seems that honey bee colonies are stressed… their immune systems are unable to cope with the multiple insults and the colony spirals downwards, leading to colony demise.”
The Willamette Valley suffers fewer CCD losses than the rest of the nation, and Sagili points to factors here in Oregon that contribute to this. “We have a diversity of pollen resources, good nutrition that helps them survive. Many of the many plants we consider weeds are helpful. Himalayan blackberries, fireweed and vetch and other weeds; we have them here in abundance when compared to other states.”
Sagili estimates that Oregon lost 25% of bees in the winter of 2009 and 17% in the winter of 2010. “Though seventeen percent is too high,” Sagili says, “they’re nowhere near the national numbers.”
The practices science blames on the problem of CCD; increasing reliance on one-crop farming, pesticides, genetically modified crops and thousands of miles of bee travel, may be the reason our valley is less impacted by CCD. The discoveries also pose a question that all of us who farm, or eat, may need to answer: how industrialized do we insist our food sources be when our top pollinator dies from our methods?
For more about disappearing honeybees:
Salem Progressive Film Series presents:
The Vanishing of the Bees-a documentary that examines the alarming disappearance of honeybees (known as Colony Collapse Disorder) and the greater meaning it holds about the relationship between mankind and mother earth
Guest speakers: Mike Rodia, Willamette Valley Beekeepers Association and Carolyn Breece, Faculty Research Assistant, Entomology Program, Oregon State University.
Thursday, April 12th 7 PM
191 High Street NE