Bees do it -- pollinate crops, that is -- but there are fewer and fewer buzzing around and doing that important agricultural work in Pennsylvania and the rest of the nation.
Charles Vorisek, president of the Pennsylvania State Beekeepers Association, said the state's beekeepers probably have lost more than half of their colonies over the winter, and that could affect fruit and vegetable crop production.
"We don't have solid survey numbers yet, but I've been talking with beekeepers for the last couple of months and we've taken quite a hit this year," said Mr. Vorisek, who owns a commercial honey and pollination operation near Linesville, Crawford County. "It's not unusual for me to hear 50 percent to 70 percent colony losses."
Pennsylvania beekeepers lost 38 percent of their honeybee colonies last year, according to Bee Informed, a partnership of the U.S. Department of Agriculture and the National Institute of Food and Agriculture formed to address bee colony decline.
Mr. Vorisek, who lost 60 of the 135 hives he manages for honey production and commercial pollination, said he bought some replacement bees from Florida and moved some hives to pollinate an apple orchard Friday morning.
"Apple orchards are very reliant on commercial beekeepers, and they do a good job of reloading to make sure they have the colonies to fulfill their contracts," Mr. Vorisek said. "But some might have to go with fewer bees, and that means there won't be as much of a crop."
A federal report released Thursday said the loss of bee colonies, which has averaged 30 percent a year since 2006 and could climb as high as 50 percent in the U.S. this year, is due to an array of factors, including parasites and diseases, lack of genetic diversity, modern monoculture farming practices and pesticide exposure.
Prior to 2006, when colony collapse disorder, or CCD, was first identified, commercial beekeepers could expect to lose about 1 in 10 hives over a winter.
"Pesticides are definitely part of the story, and are contributing to the overall decline of bees and other pollinators. I do think they're a major factor," said Maryann Frazier, a honeybee researcher at Penn State University.
The scientific report -- by the federal Department of Agriculture, the Environmental Protection Agency and a host of scientists and beekeepers -- said "additional research is needed to determine risks presented by pesticides."
Coincidentally, European Union officials moved last week to ban pesticides known as neonicotinoids, which are produced from nicotine and, according to Ms. Frazier, are highly toxic to a wide range of pollinators, including honeybees, bumblebees, butterflies, hummingbirds and bats.
"I don't think it will fix things if we eliminate just those pesticides," she said, noting that one recent study found six pesticide chemicals in a bee hive pollen sample. "We're facing a very serious problem because bees have been responsible for pollinating a wide variety of fruits and vegetables.
"Apples are a big crop in the state and are being pollinated now. We'll see how that goes, but we've already seen shortages of bees to pollinate almonds in California and blueberries in Maine."
The decline in the number of honeybee hives means they can't do it as much or as well. And that threatens to cause reduced fruit, nut and vegetable production and increased consumer prices. About one-third of the nation's crops are pollinated by honeybees, producing up to $30 billion worth of food and beverages annually, the federal report said.
In addition to apples, Pennsylvania crops dependent on commercial honeybee pollination include pumpkins, raspberries, squash, watermelon and cucumbers.
Pennsylvania has 2,700 registered beekeepers and more than 5,000 bee yards containing 42,000 bee colonies.
Dennis vanEngelsdorp, a research scientist in the University of Maryland's entomology department and Pennsylvania's former state apiarist, said climate change reflected in drought, increased length of the growing season and seasonal shifts could be contributing factors to honeybee demise along with pesticide exposure and lack of good bee forage as more land is used for corn and soybean production due to higher prices for those crops.
Mr. vanEngelsdorp, who heads the Bee Informed partnership, said the EPA also needs to take a closer look at pesticide use and exposure.
The problem will probably get worse before it gets better, said Ms. Frazier, who said a turnaround won't happen until beekeepers change some of their bee management practices involving chemical controls of mites and diseases affecting bees, and agriculture reduces its use of multiple pesticides that bees are exposed to.
"The EPA has to change the way it evaluates pesticides and protects the environment," Ms. Frazier said. "It's not taking into account that bees are exposed to multiple pesticides or consider the combinations that can chemically react and bio-accumulate to become more toxic."
Nicole Bucher, a spokeswoman for the state Department of Agriculture, declined requests to make apiary experts, including state apiarist Karen Roccasecca, available for interviews.
Ms. Bucher issued the following statement, "The Pennsylvania Department of Agriculture is concerned about the impact of a reduced bee population in the state and is following the research being done nationally and by our partners at Penn State."
Don Hopey: email@example.com or 412-263-1983.