Sunday, October 10, 2010

In the News: CCD Research

Quite a number of you have sent me the recent New York Times article on the discovery of the cause of colony collapse disorder or CCD. Firstly, thanks to everyone who thought to send it in; I try to keep up on the news, but there is quite a bit of it. By sharing any beekeeping related tidbits you run across you not only help me keep up, but let me know what kind of things you are interested in.

I like that. I’d also like to share my interpretation of the paper and the reaction that followed.

So, as seems to be the norm in the news, the story has come across a little differently than it was originally intended. The title of the NYT article says it all: Scientists and Soldiers Solve a Bee Mystery. While I understand their enthusiasm, the actual research article on PLoS ONE makes no such claim. Rather, their research points to the combination of Nosema ceranae and an Invertebrate Iridescent Virus (IIV) as the proverbial straw that broke the camels back, NOT the exclusive causative agent of CCD.

In their relative small scale study (41 colonies) they found a statistically significant correlation between colonies suffering from CCD and a co-infection by nosema ceranae and IIV. The combination of both N. ceranae and IIV type 6 was detected in 100% of the collapsed or failing colonies in a small scale study done in 2006. Similarly, follow up studies on an observation hive undergoing collapse in 2007 and 9 colonies in Florida in 2008 showed that the combination was present in all colonies that collapsed.

Even with such a small sample size, such a strong connection is hard to ignore, but there is a fly (bee?) in the ointment for anyone who would like to believe that they found the one true cause of CCD.

In the 2006 study (n=31), N. ceranae and IIV were found in 9 and 7 of the health colonies, respectively. This clearly indicates that co-infection by these two diseases alone is not enough to result in colony collapse.

This is where the paper gets both extremely cautious and a little bit weak. While they mentioned that a variety of other parasites and diseases have been implicated in CCD and even went to far as to identify many of the co-infections present in the studied colonies, they pointedly ignored some other probable influences such as the stresses of migratory beekeeping or pesticides, both of which have been linked to CCD. These influences weren’t denied, but they weren’t accounted for or even mentioned in the study- with the exception of their control group, an isolated apiary in Montana, which they stated was non-migratory.

Normally, this wouldn’t be a big problem. It is common to limit the scope of a study to avoid over reaching or ‘sprawling’. However, an article by CNN revealed that one of the lead investigators has received a grant from BAYER, a pharmaceutical company that produces some of the neonicotinoid pesticides that other studies have linked to colony collapse. This potential conflict of interest was not noted in the paper OR to the reporter who wrote the article, casting a bit of a shadow on the impartiality of their interpretation of the data.

In the future, I hope that studies will look for not only co-infections by these two diseases, but for the presence of pesticides and other stressors as well. In the mean time, this paper has reinforced my belief (and that of many other beekeepers) that CCD isn’t caused by any single thing. Rather, it is a result of many factors such as diseases, pesticides, poor management techniques, and unsustainable practices within the commercial beekeeping industry, that have come together to form the perfect storm of colony collapse.

Keep on checking back for updates on this and other beekeeping stories!

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