The Classroom – May 2019
Q A Sauna for the Bees
Thanks for all your help and humorous advice through the years, I always enjoy your column and read it first!
I have been talking with a fellow apiary inspector about the various gizmos that heat a frame or hive to “kill mites.” The one below says that one heats the hive for 1-2 hours at 40-47C (104-116F) which kills all the mites. Various ones use temperatures around that range.
Beekeepers who have kept and transported bees for their livelihood have stated that bees will die at 104F.
Research has shown that a queen’s sperm viability can drop to 20% if she’s exposed to 104F.
What’s the deal? I can see taking the queen out before treating but what about the bees? What if the thermostat isn’t calibrated correctly or does it even matter at 104-116F? See study below.
Thank you for your Advice and Wisdom!
County Bee Inspector
Somewhere in Ohio …
Hello County Bee inspector somewhere in Ohio. I worked for State Gov. in the past and understand necessary anonymity. :)
Honey bees maintain the temperature of the brood nest between 32°C (89.6F) and optimally 35°C (95F) so that the brood develops normally. This is the goal of a honey bee colony in order to be as productive and healthy as possible. “Research has shown that even small deviations (more than 0.5°C) from the optimal brood temperatures have significant influence on the development of the brood and health of the resulting adult bees. Bees raised at sub-optimal temperatures are more susceptible to certain pesticides as adults (Medrzycki, 2009). Interestingly, pupal developmental temperature affects the probability of the task allocation in the resulting adult bees (Matthias 2009).”
Everything, or most everything in this life is a tradeoff. We have this huge significant introduced parasite of Honey Bees, the Varroa destructor mite. We beekeepers have been given pesticides to keep it under control. They work but as you know there is collateral damage to our bees. Not as much as letting Varroa populations go crazy and the Varroa/Virus legacy being let loose. Killing a little bug (Varroa) on a big bug (Honey Bee) with pesticides is not perfect. But, we don’t have too many alternative choices if we are to keep our colonies alive and not turn into Varroa Bombs to “infect” other colonies of ours or our neighbors’.
Temperatures of 104F to 116.6F kills most all varroa mites. Beeswax comb starts to soften at those temperatures. Honey bees die at 114.8F. Honey bee larvae as you read above are biologically designed to develop optimally at about 93F. Queens and the sperm that is stored in them are negatively affected at higher than 93F.
I think we as beekeepers have a suite of tools to control varroa; while not perfect, some have less impact on the “bees” of all castes in a honey bee colony than others. Instead of simply and one dimensionally looking at the “Ads” online or in the magazines, I think going to the Honey Bee Health Coalition, Tools for Varroa Management Guide is a solid place to start.
Q Horizontal Hive
I would like to thank you for all of the good information you have given to everyone who reads “The Classroom,” it has inspired me to try a lot of different things in the past years. I live around 30 miles south of Dallas, Texas, and looking to trying a Horizontal Hive that will hold 30+ frames. I would like your feedback on this subject.
Thank you for the compliment and glad honey bees have inspired you as they have inspired me.
Honey bees will live in just about anything that has the minimal right cavity volume/size. African Honey Bees that you have in Texas, will live in all of the familiar and others. They will live in mailboxes, animal burrows underground, outside on tree branches, old gas tanks, under tree roots’ voids, Langstroth size bee hives, top bar hives, hollow trees, wood piles, the trunk of an old Buick in a salvage yard and on and on and on.
My concern for you Allen is not what you want to use as a movable frame hive in the subtropical climate of central Texas. My concern is where you get your bees from, where you get your Queens from, and what you do if your bees exhibit early, or in the future acquire and exhibit, overly defensive characteristics. I saw several human deaths and many pet, livestock and wild animal deaths from fatal stinging incidents while Chief of the Apiary Section in Florida, and hundreds of nonfatal stinging incidents. I just googled up African Bee stinging deaths in Texas. I don’t want you, a family member, a neighbor, or the mailman to have a bad experience.
All that to say, you can do this and do this safely and have fun but as you probably have already experienced as a beekeeper 30 miles south of Dallas, you have to be on your game with these grumpy bees.
I’ve watched our industry struggle with the mite problem since it started in the mid 80s. There have been many theories and research into how to deal with the effects of the mites. There is still a lot of mystery of why hives or even entire apiaries empty out and leave behind hives without hardly a bee, dead or alive, full of honey, that often times are never robbed at a time of the year when robbing was historically the worst.
The working theory today seems to be that the brood gets mostly dead and it’s every bee for herself exploding in all directions to find a live hive out there to join; in the process carrying mites and disease with them. The problem is I’ve never seen a hive gain bees, even if 30 empty out and only one remains. I know what drifting looks like and I don’t see it. Your thoughts.
Good morning Dale,
There are several questions here. Let me see how deep in the mud I can get, hang on. There is no mystery 30 years past Varroa introduction.
Just as a starting point, anytime a new disease or parasite is quickly introduced into a human, livestock, wild animal, insect population that has not been challenged in a Darwinian way they always die. The strong survive if their genetics allow response to this new health challenge. If not there is widespread die off and lost species. Just ask the Dinosaurs.
Same thing with introduction of varroa mites and their direct impact in feeding on honey bees, and the viruses they vector, and those viruses that were benign and latent that now ‘bloom’ and cause wide spread health issues in a honey bee colony. In order to save the beekeeping industry, not because of honey production, but because of agricultural pollination needs, varroacides (pesticides) were introduced to control varroa and stabilize the industry. It saved the industry but it didn’t get….