The Silence of the Bees, Aug 07 | Disappearing Honeybees Raise Alarm


Entire bee colonies are disappearing, and scientists have not yet determined why. (PHOTO: Kurt Michael Friese)

Listen closely in your garden. Have you noticed that it is just a little quieter this year? The gentle hum of the honeybee, the buzz that is the sound of life in gardens, orchards, and farms, is diminishing all over the world, and no one knows yet quite why.

Colony Collapse Disorder

What has come to be called “Colony Collapse Disorder” (CCD) was first reported in the U.S. just last fall by Florida beekeeper David Hackenberg. Unlike the chronic problems apiaries deal with every day, such as the varroa mite, this new syndrome was puzzling, and very frightening. Whole hives, or colonies, were simply vanishing, leaving no clues. It’s not that the bees were dying, they seemed to have simply left and not returned.

According to a June 19th report in the Palm Beach Post by Susan Salisbury, “The bee crisis was first reported in Florida in November and has since been reported in 35 states, five Canadian provinces and Europe. The Apiary Inspectors of America surveyed 384 beekeeping operations—representing more than 143,000 colonies—from September 2006 to March 2007 and found a total loss of about 32 percent.”

Honeybee colonies will sometimes undergo what’s called “asexual reproduction by swarming,” wherein a portion of the colony will split off to form a new hive elsewhere. Sometimes there will be an “absconding swarm,” wherein the queen takes all the workers and drones that can travel and leaves for a new hive. But half a hive remains in the case of asexual reproduction, and when absconding a hive will wait until all the capped brood (eggs) has hatched and developed.

With CCD, there is a total absence of adult bees, and there are no carcasses left behind. The capped brood is still there, as is a store of food, both honey and pollen. The queen is noticeable outside the hive, and if there is any workforce left behind, it is made up of immature adults who refuse both their own food stores and provided feed. Here is where it gets even more mysterious. That abandoned food supply would in other cases be stolen by other bees, or attacked by secondary predators such as the wax moth or the small hive beetle. If and when they come, their attack is noticeably delayed, often by weeks.

Jerry Hayes, an apiary inspector with the Florida Department of Agriculture, is one of the members of a CCD working group that also consists of researchers from Penn State University, University of Montana, North Carolina State, Columbia University, and the U.S. Department of Agriculture. He summed it up this simply: “Bees are leaving the colony and not coming back, which is highly unusual for a social insect to leave a queen and its brood or young behind. They are seemingly going out and can’t find their way back home.”

A Potentially Disastrous Impact

The working group estimates that from 25 to 33 percent of U.S. colonies have collapsed since last fall. Some apiaries have suffered 90 percent losses. With fully one-third of agriculture dependent on bees for pollination, the potential impact on our food system worldwide may well be devastating. A 2000 Cornell University study concluded that the direct value of honeybee pollination to agriculture is more than $14.6 billion per year in the U.S. alone.

Since there has not yet been a full year of crop production since the CCD outbreak has been noticed, it is hard to measure its negative impact thus far, but the potential is enormous.

Imagine what would happen to our food supply if the honeybees were to disappear: no oranges, lemons, limes, cherries, apples, pears—in fact, no tree fruit of any kind. The whole squash and melon family would cease production. Cruciferous vegetables like broccoli and cabbage could not continue. Almonds, raspberries, avocados, alfalfa, all gone.

Possible Causes

Matt Stewart and his wife Patty operate Noble Bee Honey out of South Amana. Like most who have looked at the problem, the Stewarts feel there is more than one cause. Among them is the possibility that the common practice of feeding the bees high fructose corn syrup (HFCS) during the off-season may be partly to blame. Matt cites the opinion of Mike McInnes in the July 2007 issue of American Bee Journal, who claims that HFCS disrupts the development of young bees, which might be one stressing factor.

The Stewarts’ apiary has gone from 80 colonies in 2004 to just 30 today, and they believe factors other than CCD, notably the varroa mite, have caused their difficulties. It has been a plague on apiaries for 20 years and has annihilated 90 percent of the wild honeybee population in the U.S. However, since the likely causes of CCD are manifold, the mite may also be a causal factor in the current emergency.

Reasons for the syndrome range from insecticides, shallow gene pools, and genetic modification to electro-magnetic fields and even cell-phone use. Stewart doesn’t put much stock in that last one, the result of a recent German study: “I never let my bees use a cell phone,” he said.

While no answers are available yet, preliminary conclusions seem to be pointing toward two primary factors. First is the use (and overuse) of a class of chemicals called “neonicotinoids,” insecticides commonly used both in industrial agriculture and in home gardens since the banning of organophosphates, which themselves had a myriad of detrimental effects on the environment. Since neonicotinoids kill insects extremely effectively by becoming systemic in plants’ leaves and stems, the hypothesis is that it does so to a slightly lesser degree in the flowers and pollen. Bees take a sub-lethal dose with them to their hives; it builds up in the hive’s food and honeycombs, and eventually causes the foragers to lose their normally keen sense of direction (resulting in their disappearance).

The second potential culprit is the widespread use of Genetically Modified Organisms (GMOs), specifically so-called Bt (bacillus thuringiensis) crops. These are unlike the chemical sprays in that instead of being applied to, for example, broccoli, the plant’s genome is altered by introducing a Bt gene that itself is lethal to insects. From there—it is hypothesized—the results are similar to the neonicotinoids.

Meanwhile, organic beekeepers across the country are claiming no loss from CCD.

Hayes estimates that unless we find the cause, and control it, by this fall, the impact in the U.S. and around the world could well be catastrophic. The social upheaval associated with the loss of one-third of the crop species diversity may be more frightening still.

Without more money and more researchers, Hayes says, it will be very difficult to meet that deadline.