April 1, 2008
Researchers Still Puzzled By Honeybee Die-off
By Laura King
Pollination by managed honeybees is vital to many crops grown in Florida.
It has been a year since Florida beekeeper David Hackenberg first noticed something was wrong.
“It’s kind of hard to explain,” Hackenberg said. “They’re gone.”
Hackenberg, owner of Hackenberg Apiaries, has been a beekeeper for more than 40 years, and he has never seen anything like it. Boxes full of honey, but no bees.
Last fall he had been checking one of his hive locations in Ruskin for bees to take south for the spring pollination season when he discovered that out of 400 hives, 360 were empty.
Hackenberg immediately pick-ed up the phone and called Jerry Hayes, Assistant Chief of Apiary Inspection at the Florida Department of Agriculture and Consumer Services. The two spent nearly an hour on the phone discussing the mystery.
“It really didn’t get any traction with me at first, because beekeepers have been losing 20 to 30 percent of their bees every year from varroa mites that were introduced in 1987, but when beekeepers started saying that their bees were just disappearing I got a little more curious, and things just kind of developed from there,” Hayes said.
The disappearances are part of a phenomenon called colony collapse disorder that has spread across the country like wildfire, producing millions of dead bees and plaguing some beekeepers with more than 80 percent losses in the past year.
“Five years ago if you talked about a 30 percent loss it was a bad deal, but now if you only have a 30 percent loss you’re not as bad off as your neighbors with those 60 and 70 percent losses,” Hackenberg said.
This year Hackenberg expects about 950 of his 3,000 hives to survive the winter season. He had been hoping to send four semi-truck loads of healthy bees to California this winter to help almond pollination, but instead he will be struggling to send two tractor-trailer loads.
“The latest estimation suggests that by 2010, California almonds will need every honeybee colony in North America just to be pollinated adequately,” said Jamie Ellis, Assistant Professor of Entomology and Nematology at the University of Florida.
But if all the bees are going to California for almond pollination, what will happen to citrus in Florida? Honeybees are responsible for one-third of Florida’s food production. Without the pollination managed honeybee colonies provide, Florida oranges, lemons, limes, and other fruits and vegetables would disappear.
For consumers, the adverse impact could mean reduced availability and higher costs of certain foods. More than 130 crops in the United States rely on the pollination that honeybees provide, and even though the United States remains a major supplier of food to the world, some statistics suggest the United States is becoming increasingly dependent on imported foods.
“Maybe it’s a moot point if we don’t care where food comes from, but I think U.S. consumers do care where food comes from,” Hayes said. “I think the U.S. has a premium product.”
The cause of colony collapse disorder is still under investigation. Researchers are considering several factors, everything from mites to malnutrition, but if honeybees serve as an environmental barometer, the loss of bees could signal a decline in the health of the environment.
“Honeybees are good biological indicators, largely because they can forage up to three miles from their colony,” Ellis said. “In that area they are exposed to any number of things. Oftentimes, you can tell a lot about what’s in the environment just by what’s in bee colonies. Bees are going out there, getting exposed to it, and bringing it back.”
Researchers now know that pesticides are part of what honeybees bring back to their colonies and that certain pesticides are highly toxic to honeybees. A study at North Carolina University in 2004 found that when insecticides are mixed with certain fungicides the toxicity of the insecticide increases a thousand fold.
“Pesticides are designed to kill bad bugs,” Hayes said. “Pesticides, when they’re used well, are a great tool to protect Florida’s agriculture and environment. The problem is that the bad bugs’ physiology is just like the good bugs’ physiology. No one is trying to kill the honeybees specifically, but they’re exposed to the same chemicals.”
Whether pesticides are the cause of the disappearances remains to be seen. Many scientists believe colony collapse disorder is caused by a combination of factors, Ellis said, which makes the disorder difficult to study. Some of those factors include chemical use in bee colonies, chemical toxins in the environment, pests, malnutrition, and disease.
“Bees are pushed very hard, and they’re fed foods that are not nutritionally complete, like natural pollen and nectar,” Hayes said. “Then we load them on a semi-truck—moving an insect’s nest, which is incredible—to take them to different time zones and different climates. Now add varroa mites and other viruses and bacteria to the mix. And we wonder why they’re dying?”
It has been a year since Hackenberg and Hayes first spoke on the phone. Researchers, faced with multiple factors to consider, race to provide a solution to the disappearance of millions of honeybees. Meanwhile, the question on the minds of Hackenberg and other beekeepers is not “Why?”, but “How long can we keep doing this?”
For more information on colony collapse disorder, contact the Division of Plant Industry, Bureau of Apiary Inspection, at (352) 372-3505, or email Jerry Hayes at hayesg@doacs.state.fl.us.
