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Have you heard about the honeybee crisis? Sometimes beekeepers discover that their hives have dwindled or gone extinct over the winter. Such events are usually rare, however, and multiple colony collapses are typically local phenomena. But across America, beekeepers are now reporting alarming numbers of hive deaths. A 20% loss over the winter is normal, but beekeepers in California report losses up to 60% and losses have been even higher in Texas and on the east coast.

My dad’s been keeping bees since 1977. He started the hobby when we lived in suburban Maryland, on a half-acre yard cultivated with peach, pear, apple, plum and cherry trees, hedges of blackberries and raspberries, blueberry bushes, a strawberry patch, a full vegetable garden and a perimeter of grapes. The hives were tucked between a neighbor’s evergreen and our chinese chestnut (I associated that region of the yard with painful sharp things) and got lots of sun—a perfect environment, even if the surrounding neighborhood exhibited a far more suburban landscape. In those days, my dad says, he occasionally got honey yields as high as an impressive 110 pounds per hive. But talking with him on the phone yesterday, he declared, “The golden age of beekeeping is over.” In the late 1980s, he began finding mite infestations in his hives. Soon other beekeepers at the Susquehanna Beekeepers’ Association meetings were reporting similar problems, and domestic bee colonies never really recovered. About a decade ago, my parents moved to a rural part of the county. Close by are fields farmed with soybean, corn, oats and sunflowers, but the surrounding woods shade the hives and the microenvironment is just a little too damp. Last year my dad had three hives, but this spring he’s left with just one. Is it the mites? Is it part of the nationwide trend of colony deaths?

My dad in the golden age of beekeeping, 1978.

Part of what’s brought the national decline of bee colonies to popular attention is the puzzling fact that no one knows what’s causing it. The syndrome’s been given its own name: colony collapse disorder, or CCD. But unlike mite infestations, viral diseases, or other afflictions which show evidence of infection, the only symptom of CCD is an absent colony. The assumption, of course, is that the bees leave the hive and die out in the field. But why? An article this week in PLoS outlines dozens of possible agents, including diseases, agricultural and medicinal chemicals, genetically modified crops, high stress brought on by new handling procedures in the industrial bee market, and finally difficulty in maintaining brood temperatures, which could be a result of any of the previous factors. According to a recent article in the NY Times, Maryland has been spared the CCD trend that has been silencing hives across the rest of the country—though the state has still suffered high bee mortality. The 45% loss Maryland beekeepers report is being attributed to unseasonably warm weather in November and December. The high temperatures induced premature brood bearing, so the January cold snap froze many of the bees right there in the hive, as they persisted in tending the broods instead of getting food and staying warm. But this doesn’t comport with my dad’s experience, who opened his boxes this spring to find two of his hives empty and one seriously weakened.

My aunt Geanie in 1984.

Confirming the obvious, my dad explains: “Bees don’t stand around and chat. They have their job and they get right to it.” But this spring he observed behavior he had never seen before. Rather than busy, the bees looked lazy and confused. As a child, sitting in a lawn chair near the house, I used to watch the bees zero in on the white hive boxes and then zoom back out, unidirectional. During the active day hours, the airspace a dozen yards away was transformed into a 3D highway. But in the warm days of this spring, my dad has watched the workers fumble, circle and buzz haphazardly in front of the hive. They’re not foraging for this season’s nectar, and without honey stores, he doesn’t expect the hive to live through next winter. Apparently, the bees have cognitive or behavioral problems. Perhaps the bees that venture from the hive are dying away from it because they can’t find their way back. But what’s causing the malfunction? If anything, my dad’s bees last year were unusually healthy, the strongest hive producing an astounding 170 pounds of surplus honey. The honey was different, too, a new flavor produced from the neighbor’s new crop: alfalfa. The talk among other Maryland beekeepers is that genetically modified, “Roundup Ready” alfalfa, engineered to tolerate the herbicide Roundup, may be harmful to honeybees. The science articles I scanned don’t evidence this concern; there are no data suggesting that GM crops harm honeybees, and the PLoS paper points out that states like Illinois, with high loads of GM farming but no real CCD problem, suggest that the culprit lies elsewhere. Still, it’s easy for me to imagine that the profound anthropogenic influences on our environments, even in the last few years, are behind the honeybee mystery. If we discover the cause of CCD, the answer will be embedded in the local ecology. Bee deaths are not the only worrying phenomenon sweeping rural Harford County, Maryland. My dad covered his hives with a tarp this weekend to shield them from a helicopter spraying pesticide against gypsy moths. Four neighbors have lost a total of about 15 acres of foliage to the unstoppable larvae, the worst in anyone’s memory. “It looks like winter,” my dad said of the denuded trees, and he’s not sure if they will survive. So far the pests have not made the leap across the gravel road, and my dad is hoping the season, or pesticide, will work in his favor.

This entry was posted on Friday, June 15th, 2007 at 4:13 pm and is filed under Phenomena. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.