Honey bee CCD update
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
If you have been listening to radio or reading papers the last few weeks, chances are that you have already heard about the alarming honey bee die-offs around the country. The phenomenon is officially named Colony Collapse Disorder (CCD). This disorder has the media all excited because it is large in scale (27 states are affected), came in quick (Colonies that were fine in August or September became collapsed around October and November.), and hit people hard (Many beekeepers with hundreds to thousands of colonies are losing 50 to 90 percent of their colonies.). Nationally, it is estimated that we have lost about 600,000 colonies. The worst of all, we do not yet know what causes it!
The symptom seems to be for bees simply to disappear. That is why initially peopled called it disappearing disease (or fall dwindle disease). A colony with 30,000 bees checked one week ago – apparently healthy with lots of honey and pollen – suddenly has nothing, or a handful of bees with a queen left, but with lots of food and many frames of capped brood left. Very few dead bees are found inside the hive or near the entrance. Strangely, wax moths, small hive beetles, and robbing bees are slow in moving into such newly abandoned colonies – two to three weeks later – while normally they move into defenseless colonies right away.
I just attended an emergency conference in Washington, DC a few days ago and we had a brainstorming session on possible causes of CCD, what we should research and where to obtain the funding. The short answer is that we still do not know what is the cause of CCD. A list of culprits include nosema ceranae (a protozoan parasite that infects adult bee mid-gut), viruses, varroa mites, or a new pathogen. Tracheal mites, pesticide use, various supplemental feeds are tentatively excluded. It is interesting that someone at the meeting reprinted an article published in 1897, complaining about the same symptoms seen in Colorado as what we are seeing today: most workers gone with a queen and some workers with lots of brood left in colonies. That was prior to both the varroa and tracheal mites, prior to the use of neonicotinoids (and organophosphates and pyrethroids).
It seems almond growers in California, who need about half of the bees in the country (about 1.2 million colonies) did not have an obvious shortage of bees for pollination, but they did see a $15-25 per colony increase in price. Blueberry growers in Maine are experiencing a 50 percent increase in bee prices, one grower told me. I do not think Michigan will be as bad, but I would not be surprised if you see a $10 per colony increase in price.
Dr. Huang's work is funded in part by MSU's AgBioResearch.