Disease and drought are causing damage to hive populations.
A honeybee crisis is playing out right now in the almond fields of California, where producers can’t get enough hives to pollinate their crops. An abnormally high rate of overwinter losses brought on by last year’s drought and colony collapse disorder (CCD) reduced hives available for deployment.
"They are in a panic out there right now," said David Westervelt, assistant chief of the Florida Bureau of Plant and Apiary Inspection. "I got a call yesterday that they are still about 200,000 to 300,000 hives short. If they don’t have two hives of honeybees per acre, they can’t get their crop insurance."
Almonds, the leading crop dependent on honeybee pollination, are on the bleeding edge of an apparent honeybee crisis in this country. Hive populations are steadily declining due to disease and drought, even as demand for their services increases. The result: rental prices that now hover around $200 per colony, compared to $150 per colony in 2010 and only $58 per colony in 2004.
The cause of the honeybee crisis received attention at Commodity Classic this week as part of the Bayer Crop Science Ag Issues Forum. Westervelt presented along with David Epstein, an entomologist with USDA's Office of Pest Management Policy. Together, they dissected the source of bee population declines.
CCD, a phenomenon first identified in 2006, often gets the most newspaper headlines. But the pair of experts agreed that a complex variety of factors contributes to loss of hives each year. First, 10% to 15% of colonies are lost each winter regardless of CCD, Epstein said.
Starting in 2006, winter losses shot up to 30%. Though they have been declining for the last several years, Epstein said that they may rise strongly again this winter, once all the data is tallied. That’s because of the drought, which reduced forage acres and water that bees use to cool hives. "The drought was very detrimental to beekeepers," Westervelt said.
Contrary to some newspaper headlines, "not all colony deaths are due to colony collapse disorder," said Epstein, who recently held a conference on the topic. "The consensus is that it’s not just one factor. It’s a complex set of stressors and pathogens."
Westervelt agreed that the cause of CCD is actually the synergist effect of lots of stress. "We have beekeepers that are not having a collapse," he said. "Most of them run a good operation and can treat the bees right off the bat. They keep a good handle on the situation."
Meanwhile, a lot of agriculture is at stake. In a paper published last year, Nick Calderone of Cornell University estimated that commercial bee pollinators bring $11.7 billion in agriculture directly to the economy and another $5.4 billion indirectly. The leading crops pollinated by honeybees are almonds, apples, melons and alfalfa seed. "One-third of the food we eat is directly linked to the honeybee," Esptein said.
As demand for honeybee pollination increases, the number of commercial hives is declining. At last count, in 2008, it stood at 2.4 million. That has led to a sharp rise in rental prices.
Research since the outbreak of CCD has linked more than 20 new viruses and several bacteria to the disease." There’s been more research into diseases affecting honeybees in the last six years than the last 600 years," Westervelt said.