May 18, 2009 | Gene Brandi will always rue the summer of 2007. That's when the California beekeeper rented half his honeybees, or 1,000 hives, to a watermelon farmer in the San Joaquin Valley at pollination time. The following winter, 50 percent of Brandi's bees were dead. "They pretty much disappeared," says Brandi, who's been keeping bees for 35 years.
Since the advent in 2006 of colony collapse disorder, the mysterious ailment that continues to decimate hives across the country, Brandi has grown accustomed to seeing up to 40 percent of his bees vanish each year, simply leave the hive in search of food and never come back. But this was different. Instead of losing bees from all his colonies, Brandi watched the ones that skipped watermelon duty continue to thrive.
Brandi discovered the watermelon farmer had irrigated his plants with imidacloprid, the world's best-selling insecticide created by Bayer CropScience Inc., one of the world's leading producers of pesticides and genetically modified vegetable seeds, with annual sales of $8.6 billion. Blended with water and applied to the soil, imidacloprid creates a moist mixture the bees likely drank from on a hot day.
Imidacloprid and clothianidin are chloronicotinoids, a synthetic compound that combines nicotine, a powerful toxin, with chlorine to attack an insect's nervous system. The chemical is applied to the seed of a plant, added to soil, or sprayed on a crop and spreads to every corner of the plant's tissue, killing the pests that feed on it.