Shortly after I graduated high school, commercial apiaries started to report massive losses of honeybees. Honeybees are probably the most economically valuable insects in the world, and are responsible for pollinating most of the food we eat. Here in the United States there’s an entire industry built up behind honeybees, with most US honeybees being transported to California to pollinate almonds at some point in the year.
Unfortunately there are a lot of wrong-headed things out there in the press. One common idea I see spread through facebook meme, such as the image to the left, is that biotech crops are responsible for killing the bees. This is a hypothesis that’s been pretty thoroughly researched in a variety of ways. Industry data very strongly indicates this is not the case: a recent meta analysis performed by Monsanto published in PLOS ONE reviewed experiments done by a wide variety of researchers and concluded that there were no effects on survival of bees on Bt crops. Academic research is consistent with the industry data, from a 2005 review on the nontarget effects of Bt crops in the Annual Review of Entomology:
Neither Bt cotton nor Bt maize requires bees for pollination, but cotton nectar is attractive to them and produces a useful honey. Maize pollen may be collected when other pollen sources are scarce. Pre-release honey bee biosafety tests have been conducted for each Bt crop registered in the United States, including Cry9C maize and Cry3A potatoes. Each test involved feeding bee larvae and sometimes adults with purified Cry proteins in sucrose solutions at concentrations that greatly exceeded those recorded from the pollen or nectar of the GM plants in question. In each case, no effects were observed. The rationale for requiring larval and not adult bee tests is questionable, because adult bees ingest considerable quantities of pollen in their first few days post emergence. Larvae, particularly later instars, also consume pollen along with jelly secreted by nurse adult bees, but only recently have there been attempts to quantify pollen ingestion by individual larvae. Other studies with bees fed purified Bt proteins, or pollen from Bt plants, or bees allowed to forage on Bt plants in the field have confirmed the lack of effects noted by the U.S. Environmental Protection Agency (EPA). Post-release monitoring programs are now underway to assess impacts of North American GM crops on pollinators under commercial field conditions.
Admittedly, there could be better data on this subject. For instance some of the research that’s been done has been done without some essential controls, like this German group which fed honeybee larvae a mixture of Bt pollen without determining that active Bt proteins were present in the pollen. The data, however, is generally against the idea that Bt crops harm bees. Continue reading “Colony Collapse Disorder: An Introduction” →