It is hard to overestimate the importance of bees in the food chain. Almonds, carrots, melons, apricots, cherries, pears, apples, prunes, plums, cantaloupe, onions, avocados, kiwi, blueberries, cranberries and many more fruits and vegetables depend on honeybee pollination. In fact, of the 100 crop species that provide 90% of the world’s food, over 70 are pollinated by bees. Meat, milk and cheese production are reliant on pollinated crops that animals eat. The monetary value of honey bees as commercial pollinators in the United States is estimated at about $15-$20 billion annually. “It’s hard to imagine American agriculture without bees,” stated Dan Rather recently in an investigative report, Bee Aware. And while bees struggle against many obstacles to survive — environmental pollution, climate change, infections, and poor diet from low-protein monoculture crops — the role of pesticides, particularly systemic pesticides, has been initially played down.
The industry has said all along that this class of pesticides is safe. In the meantime, many critics contend that the Environmental Protection Agency (EPA) has not been asking the right questions, focusing on the short term lethal impact of pesticides rather than analyzing the complicated ways in which pesticides interact, the sublethal dozes of pesticides and the interaction with other stressors.
Honey Bees and Colony Collapse Disorder
About six or seven years ago, beekeepers started to notice massive disappearance of bees which led to the collapse of bee colonies. Beekeepers were reporting collapses of anywhere between 30-90% of bee colonies each winter. Some beekeepers feared the loss of nearly all of their colonies. This was far worse than anything witnessed before. And while the health of beehives has been on a decline since the 1980s, as a result of new pathogens and pests, such as Varroa and tracheal mites, this new phenomenon, which came to be known as Colony Collapse Disorder (CCD), had no immediate explanation.
CCD is often associated with: a) rapid loss of adult worker bees, b) few or no dead bees found in the hive, c) presence of immature bees (brood), d) small cluster of bees with live queen present, and e) pollen and honey stores in hive.
“I have never seen colonies collapse like this,” stated Dennis vanEngelsdorp, State Apiarist with the Pennsylvania Department of Agriculture (PDA) and senior extension associate in entomology for Penn State, for a Penn State publication. Maryann Frazier, a senior extension associate at Penn State, similarly stated, “[t]hey’re leaving behind their brood, the honey, the pollen, all their resources. For bees, this is very, very odd behavior.”
“We could be seeing the end of beekeeping,” Tom Theobald, a Colorado beekeeper and one of the founders of the Boulder County Beekeepers’ Association, told me in an interview earlier this month. Mr. Theobald has been concerned about the impact of pesticides, and in particular, systemic pesticides, on bees for a long time. Ever since he experienced heavy losses of his hives sometime in 2006, however, he has been critical of the EPA’s approval of one particular systemic pesticide, clothianidin, and asking questions which challenge the core basis of America’s pesticide policy.
What’s All the Pesticide Buzz About?
Many factors were considered as the cause of CCD. “We blamed it on mites, viruses and a lot of other stuff because we didn’t know what to blame it on,” commented another beekeeper, David Hackenberg. It was not until recently, however, that pesticides were given a serious consideration. Researchers like James Frazier, Ph.D, a professor of entomology at Penn State’s College of Agricultural Sciences, and his team have been actively studying CCD and paying particular attention to pesticides since at least 2007. In a study published in March 2010, Professor Frazier and his team found in hives across the United States, on average, six different pesticides, and in some cases, as many as 39 pesticides. Such a high level of pesticides is “beyond the level that was expected when the chemicals were introduced and approved for use.” While the study did not focus on any one particular pesticide, but rather analyzed the presence of multiple pesticides and demonstrated the presence of high pesticide levels in pollen and wax, “[a]lmost 60% of the 259 wax and 350 pollen samples contained at least one systemic pesticide…” The authors’ concluded that the “98 pesticides and metabolites detected in mixtures up to 214 ppm in bee pollen alone represents a remarkably high level for toxic contaminants in the brood and adult food of this pollinator.”
Professor Frazier’s concern and that of an increasing number of other researchers and beekeepers is that the long term exposure to pesticides may cause sublethal impact on honey bees that alters their behavior, learning, memory and development. Furthermore, “[w]hile exposure to many of these neurotoxicants elicits acute and sublethal reductions in honey bee fitness, the effects of these materials in combinations and their direct involvement in CCD remain to be determined.”
Strangely, pesticide manufacturers are not required to test for the interaction with other chemicals. But the results of recent studies “certainly indicate that pesticides are very likely involved and that interactions with other stressors are very likely factors contributing to CCD and the decline of honey bee health,” stated Professor Frazier in a recent article.
For Tom Theobald, who has experienced significant honey bee losses, the answer was in his bee yard. An analysis of his hives in the spring and fall of 2006, in which he did not find a high population of mites, and based on what he knew about clothianidin, led him to further research this pesticide and the EPA’s approval process. Clothianidin, a systemic pesticide of neonicotinoid family, affects the an insect’s central nervous system, resulting in paralysis and death. Mr. Theobald’s article in July 2010 about the impact of clothianidin on bees and the pesticide registration process that allowed it to be marketed, despite serious concerns of the EPA’s scientists, further confirmed what Professor Frazier and many others have been saying: that the EPA’s registration process for systemic pesticides is inadequate.
I will continue the examination of the honey bee collapse with an in-depth look at systemic pesticides and the role GMOs play in this unfolding crisis. Stay tuned!