A most important regulatory tool in manipulating honey bee colonies is the smoker. See contributor Dave Cushman’s description of the apparatus and its various forms. Lighting the smoker is often problematic for some beekeepers. See this example of how to get the job done from a long-time Ohio bee inspector John Grafton.
Several other examples can be found on youtube.com. It takes time and patience to get good, cool smoke for a period of time. The history of the smoker is full of ingenious ideas as noted by Paul Jackson, retired from The Texas Department of Agriculture.
A most-often-asked question by the novice is how smoke works in calming a colony so the beekeeper can manipulate it with less chance of being stung. There have been several stock answers. One is that smoke makes the insects “think” their tree or house is on fire. Therefore, workers engorge themselves with honey in case they have to abandon the nest. This process makes them calmer (some say more “content”). And when their abdomens are distended after taking on honey, it is thought workers find it more difficult to sting intruders.
There is, however, another answer that is less anthropomorphic. Worker honey bees produce “alarm pheromone” when disturbed. In contrast to the royal and brood pheromones, the reaction to this substance is much quicker and more direct. Thus, it is called a “releaser” as opposed to a “primer” chemical, which really acts like a hormone. Alarm pheromone is also volatile and smells like bananas (isopentyl acetate) or blue cheese (2-heptanone). Smoke introduced into a colony masks the odor of these alarm signals and the bees fail to communicate with each other that they are threatened by an intruder.
P. K. Visscher and colleagues have put the latter hypothesis to the test (J. Insect Behavior 8:11-18, 1995). They used an electroantennograph, which translates chemical signals from the antenna into electrical signals that are transcribed on paper. Use of smoke caused antennae to be 50 percent less sensitive to both alarm pheromones. This effect was reversible, however, and antennal response returned to normal in 10 to 20 minutes. The investigators also tested floral odor and found the same responses, suggesting that smoke has a more generalized effect, and is not specific for alarm pheromones.
There’s not much research on the actual process of smoking honey bees. It ‘s rather like an art form; not too much, not too little. Thus, I have come to characterize its use rather like the Tao of smoking bees, employing the concept that “more might be less” and taking one’s time is a good strategy to avoid defensiveness. Contributor Jim Fischer writes that smoke is nasty stuff in general concurring that using as little as possible is the best strategy.
Other uses of smoke are also possible in a bee colony. Most recently, that from tobacco has been reported to reduce Varroa populations. Unfortunately, this natural material is difficult to control, and the exact dosage that kills mites but doesn’t harm bees is unknown. “Smoking” Dr. Frank Eischen, working at the Weslaco Bee Laboratory, has taken this idea to another level (USDA ARS Agricultural Research, August 1997). So far, he has treated bees with the smoke of over 40 plants. The technique is to take cages with 300 to 400 mite-infested bees, expose them to smoke for 60 seconds while covered in plastic, and then count the number of mites that fall off. Most smokes don’t kill the mites, it seems, they are simply knocked off the bees. If not caught by a sticky board, the mites, like the bees, “pick themselves up, dust themselves off and do it all over again.” It is not clear, Dr. Eischen says, whether the mites are confused or just irritated. Two materials that show the most promise are smoke from creosote bush and dried grapefruit leaves.
Dr. Eischen emphasizes that this smoke treatment is only experimental at the present time; he does not yet recommend the process. There are too many unknowns. And other drawbacks to this technology exist. Mites in the brood are not killed, and so the smoke treatment must be repeated several times as bees and mites emerge. It becomes important, therefore, to determine what chronic smoking with tobacco or other plants might do to a colony. Given recent debates about the effects of smoking in humans, the prognosis is not good. Too much smoke can also contaminate hive products. There is evidence that heavily smoking honey supers when removing them from a colony can give the resultant honey an off flavor.
There remain questions about disrupting the delicate balance of honey bee social structure, which relies on pheromones for internal control as described above and elsewhere. Now we know that smoke can interfere with the releaser alarm pheromone, albeit only temporarily. What might it do to the more long-term, and perhaps more significant, primer pheromone communication that takes place within a honey bee colony?
Finally, it must be remembered that all smoke is not the same. Smoker fuel it turns out is a neglected part of most analyses, but an important variable in the smoker use. See a number of ways smokers can be used to manage bees via contributor Dave Cushman.