This bee, Osmia ribifloris (on a barberry flower), is an effective pollinator of commercial blueberries and is one of several relatives of the blue orchard bee, Osmia lignaria. Similar in appearance, the blue orchard bee is also a successful commercial pollinator that is now being evaluated for use in a wider range of crops.
Since 2006, farmers, scientists and apiarists have been mystified by the systematic disappearance of bees throughout the Northern Hemisphere.
The phenomenon, known as “colony collapse disorder,” has wiped out up to 90% of the bee population during some seasons. The environmental consequences could be devastating - bees are responsible for pollinating wildflowers, which could affect the bird and butterfly populations, as well as the nation’s fruit and vegetable crops. Here in California, commercial growers rely on honeybees to pollinate avocado, almond, cherry, and plum trees. Colony collapse disorder has been blamed on everything from climate change, cell phones and malnutrition to genetically modified crops and parasites that turn bees into “zombies.”
But two studies just published in the journal Science now point to a certain class of pesticides as the cause. In a study conducted at Scotland’s University of Stirling, bumblebees exposed to neonicotinoids, which are used to control aphids and beetles, produced 85% fewer queens and gained up to 12% less weight than control colonies. Another study from the French National Institute for Agricultural Research, which focused on honeybees, found that the pesticide caused the bees to become “intoxicated” and unable to find their way back to their hives.
Is this the final word on colony collapse? Are there alternative ways to protect our food supply and our bee population? What can be done to save the world’s bees – or is it already too late?
Jeff Pettis, research leader, U.S. Department of Agriculture’s Bee Research Laboratory