Q: Measuring Honey Production
In my reading, I am confused by beekeepers not stating the method used to measure their colony’s honey production. Is it by counting the number of frames extracted and using an estimated weight, weighing frames or supers before and after extraction, changes in hive weight before and after nectar flow, weights of jars filled after bottling, or something else? And new comb weighs something too. What is the research or industry standard? Or does it “just depend”?
John Whalley
North Carolina, May
A
Commercial beekeepers in the U.S. usually measure production by the number of 55-gallon (208 L) drums they produce. They know that one drum is about 650 lbs. (295 kgs) of honey. They can count drums and then do the math to get a rough estimate. They could also count the number of supers they produce and multiply that by the average amount of honey stored per super, but counting drums is more accurate since that shows actual harvested honey.
If a beekeeper wants to know colony-level production, they can divide the total weight of honey they produced by the number of colonies producing the honey. On a smaller scale (i.e., the hobbyist level), some beekeepers might count and average the number of supers produced per colony. I hear many beekeepers talk about the average number of supers their colonies produce. Given we know how much honey goes into a shallow, medium, and deep super, a beekeeper can estimate what each colony makes if they know the number of supers produced.
Now, let me get more technical from a scientist perspective. We scientists often need to know honey production per colony for our experiments. To do this, we weigh each super of honey we remove from the hive, extract the honey, weigh it again, and use the difference in the two weights as the amount of honey in that super. No one gets every drop of honey from the combs upon extraction. It is not possible due to the viscosity of honey in the cells. Thus, we are not really calculating all the honey produced, given some is left behind in the cells. For science purposes, though, that error is spread among all supers for all colonies. Consequently, it does not bias the results too much.
Q: Alcohol Wash vs. drone brood screen
This email came from our local beekeepers association. The point I find interesting is that brood uncapping showed more reliable results than an alcohol wash [when screening for Varroa]. I wonder if we have put too much trust on alcohol washes. Should we change our approach? We are in an area where brood is always present … drone brood most of the year.
Excerpt from referenced email:
As you are aware, in early March Varroa destructor was detected for the first time in Queensland. Since this time, it has been found in multiple commercial and recreational apiaries in the Lockyer Valley, Somerset, Quilpie, North Burnett, Gold Coast and Brisbane City Council areas. Now that the pest is in your local area, Biosecurity Queensland would like to kindly request your beekeepers conduct a hive health check and report the results to the Bee 123 form. Recently we have found a number of beekeepers reporting negative results through an alcohol wash, but have positive results when drone brood are uncapped. Because of this we recommend presence testing of varroa mite through an alcohol wash and drone brood uncapping if it is present.
Another question if I may … I regularly read that queen excluders are honey excluders. I have not done a side-by-side comparison but have never felt this to be factual. Has anybody ever done a scientific comparison to proof this or are we simply repeating an old message?
Max Lindegger
Australia, June
A
Monitoring for Varroa: This is an interesting question, and the distinction lies with the intent of monitoring. If you want to know relative Varroa populations in the hives to make a management decision, then using something like an alcohol wash or powdered sugar shake to estimate the number of Varroa per 100 adult bees is the right way to go. There is sufficient research to support this with the caveat that you could easily miss Varroa when the infestations are very low. We see that all the time here. We do not interpret a “0” alcohol wash (i.e., you wash the bees and do not recover any Varroa) as the absence of Varroa in a colony, but rather that the population is low. Per the email, it sounds like the “0” washes have led some beekeepers in Australia to report they have no Varroa, but this is not really the intent of an alcohol wash.
When you want to know if colonies have Varroa at all, then the more sampling strategies you layer on top of alcohol washes, the better information you have. In that case, you would conduct adult bee washes, screen drone brood, and even screen worker brood. You might even apply an acaricide to the hive and look for Varroa fall on some type of sticky board. I get the impression from the email sent by your beekeeping association that they want to know if Varroa are present in your hives. In that case, you would need to employ multiple sampling strategies to get a better indication of Varroa infestation. This is not an indictment against alcohol washes, but rather an indication that they are not sufficient for telling you everything you need to know in this context.
Queen excluders: This is an age-old question. I, too, have heard this many times in the past. Personally, I happen to be a queen excluder user and have often made the claim that I can make as much honey in colonies with queen excluders as those without queen excluders. I do not believe they lessen honey production. Per your email, I did a quick search for queen excluder impacts on honey production using Google Scholar. I found a few studies published on this topic, but none were conclusive enough to put this debate to rest. Nevertheless, the ones I did find showed that excluders helped honey production, contrary to the “honey excluder” mantra. As stated, I find the results inconclusive because the studies were small in scale and not conducted under what I would consider commercial-scale research. Even still, the data are favorable for excluders. I typically tell beekeepers to do what they think is best regarding excluders. As for me, I like to use them.
Q: Is pool water bad for bees?
I have just started to do a couple of beehives this year. I live on a dirt road, and next door my grandma and grandpa have a pool. And my grandpa was telling me that he pulled out the pool filter and it was filled with dead honey bees. I am not necessarily concerned about the dead honey bees, but a question crossed my mind: Is pool water bad for honey bees to drink? I have read about pesticides, and stuff like that is bad for them, but I have not read anything about pool water.
Jadyn Kuipers
Michigan, June
A
I would say that, generally speaking, pool water is not bad for bees. Honey bees collect water mainly for thermoregulatory purposes. They cool the nest using water. Water can be bad for bees if it contains toxins, for example, pesticide runoff. I do not personally own a pool, but I understand most pools contain low levels of either salt or chlorine to limit algae growth. These levels are below what would otherwise be detrimental to bees. The dead bees in your grandparents’ pool filter probably were there due to drowning rather than due to collection of toxic pool water. The bees likely fell into the pool while collecting water and were unable to get out, ultimately ending up in the filter …
