Monday morning myth: small-cell foundation discourages Varroa mites

The idea that small-cell foundation may limit the reproduction of Varroa mites resurfaces frequently. However, carefully controlled research has shown that mites may actually increase on small cell foundation. A carefully researched paper on the subject by Berry, Owens, and Delaplane was recently published in the journal Apidologie and can be downloaded here.

In the states, small-cell foundation has cells that are 4.9 mm wide and standard foundation has cells that are 5.3 mm wide. But what we now call “small cell” was actually the natural cell size back in the early 1900s. At that time bee breeders thought that they could improve on honey bees by growing bigger bees that would produce more honey.

They created these beasts by manufacturing foundation with larger cells. Sure enough, in not too many generations, the bee larvae filled the cells and the resulting adult bees were bigger. We are still using these “big bees” today.

Then in 1995 some scientists noticed that Africanized bees—which are slightly smaller than European bees—had lower mite counts. So the idea was born that the natural (smaller) cell size might impede the growth of Varroa mites. This idea was supported by earlier research that showed that when immature male mites are squeezed between the bee pupae and the cell walls, they often die.

With this in mind, beekeepers started regressing their colonies. That is, they tried to do the opposite of what the beekeepers in the early 1900s did: they provided smaller foundation in the hope that male mites would get squeezed to death in the tight confines of the smaller cells.

But, just as bees on large foundation grow bigger, bees on small foundation become smaller. So, in not too many generations, the male mites were no longer squished against the cell walls—and everything was just fine and dandy in mitedom.

This is not to say regressing to small cells is a bad thing. In fact, other research shows that natural sized bees may be more efficient pollinators and more healthy in general. But don’t count on small cells to take care of your mite problem . . . it just won’t happen.

Rusty
HoneyBeeSuite

Comments

Lisa

So…what happens to the size of the bees when they’re allowed to build their own cells whatever size they’d prefer? Do they continue to build for the size they are now if they’re “big bees”? Or do they regress naturally back to being smaller? Four of my five hives live foundationless, and build their own. I notice at least a couple of the hives of bees seem small, compared to a lot of bees I see, and I never really thought about it being “more natural” for them to be that size.

Rusty

Lisa,

Really good question. Bees allowed to build foundationless comb will regress to a natural size, but not all at once. It seems that the “big bees” cannot build a natural size (4.9 mm) cell because they are just too big to fit inside while they are building it. But without foundation to guide them they will build something smaller than a commercial-size cell. These cells may be about 5.1 or 5.2 mm as opposed to the 5.5 mm they grew up in. After a few more generations they will end up building natural size comb.

I have natural comb in my top bar hive and those bees seem smaller to me. I’m getting more interested in natural comb, and I’m probably going to convert my Langs to foundationless this coming year. It’s kind of scary how presumptuous “man” can be. We try to change everything and then wonder why it’s not as good as it was. Hmm.

jess

I’m going to try to convert my Lang to foundationless this year, not so much to build smaller bees, but mostly because I’ve heard that there can be a lot of pesticide accumulation in foundation. Actually, I let them build foundationless in their upper western box last year right before winter started… I haven’t been in to check it out yet. I’m half afraid, and half excited to see what I find.

Rusty

Jess,

I agree; that’s my main motivation as well. Companies buy wax from all over the country and melt it down in one big pot and roll it out. It’s known to have all sorts of pesticides and antibiotics in it.

The situation reminds me of Fast Food Nation where they talk about how many cows can be represented in one hamburger. Rather than having substances from thousands of beehives, I’d rather go without foundation altogether–just like I go without meat.

Phillip

I began keeping bees in July 2010. When I started off, I did what I was told, but when it came time to add another brood box to my hives, I added some foundationless frames, only 5 or 6 placed between fully drawn frames. The foundationless frames were filled with lots and lots of drone brood, which were later filled with honey. So, judging from my limited experience, you can expect a large number of drones when your bees first go foundationless. But things apparently balance out inside the hive after a while.

This year I’m starting up two nucs, and I plan to go foundationless right from the start. Last summer when I saw the bees building on the foundationless frames, it was thrilling. If you haven’t seen that up close and personal before, you’ll love it.

Rusty

Phillip,

Here’s another post to look at: this one is on the proportions of drone cells in free-form brood comb. You will always have more drones going foundationless but that’s not such a bad thing.

Matt

Rusty,

Some of your ideas are worth debating. The couple who discovered small cell are Ed and Dee Lusby. Sadly Ed passed away in 2006 but Dee is going strong. She runs the Organic Beekeepers List under Yahoo-Groups. I encourage you and anyone who read your above post to copy and paste it to the Organic Beekeepers list and your mind will be blown with the responses you get.

Matt

Rusty

Matt,

First of all, the above post is not “my idea” but a restatement of a published scientific paper. I cannot take any credit.

Secondly, when it comes to dismissal of scientific evidence in favor of hearsay, nothing surprises me. We have a planet full of people who do not believe the climate is changing, who seem to believe that pesticides are good to eat, and who still believe Colony Collapse Disorder is caused by cell towers. My neighbor even believes that an old Soviet satellite caused hurricane Katrina. But wanting to believe in something does not make it so.

Show me peer-reviewed statistically significant scientific evidence derived from reproducible controlled experimentation that small cell foundation will control Varroa mites and I will reconsider. In the meantime, I pass.

Mark

I haven’t read the paper, so please correct me if I’m wrong. But, the supposition is that natural cell size reduces the varroa problem. Note, this is NOT necessarily reducing the population of varroa mites, not small cell.

What is at play is the ratio of size of drone cell to worker cell. Since it will be larger in natural cell the mites will more likely tend to the drone cells. And they do. If you use small cell foundation you haven’t done a thing as the ratio hasn’t really changed as the bees are discouraged from building drone cell the way they like.

So, if the paper says they’ve debunked small cell for varroa control by only testing with foundation they’ve missed the point completely.

Mark.

Rusty

Mark,

I’m not sure I follow you, so bear with me a moment. The hypothesis was that small cell (or natural cell) reduces Varroa mites. I don’t think it has anything to do with the ratio of drone cell size to worker cell size. Although more mites can hatch from a drone cell because of the longer development time, what attracts the mites to the drone cell is probably a pheromone. So the relative size won’t matter; mites will always be attracted to the drone cells. And when drone cells are unavailable, the mites will use worker cells anyway.

It’s been a while since I read that paper, but other papers have since been published which also conclude that small cell doesn’t inhibit mite production.

Mortimer Wilson

Greetings Rusty….i have been making and using small cell foundation from 2003 and i use no chemicals in my hives….guess what?? small cell does work 100%!!

Doug

I have read many accounts of small cell, “natural beekeepers” losing their hives over winter. V. mites will still affect them. If you don’t knock enough mites down, in late August to September, to keep your newly hatched winter bees from getting the virus, you will lose hives. No matter how much faith you have in any system of beekeeping, keep an eye on mite count. I have been letting my bees draw their own comb for two years. Just because I am too cheap to buy foundation. It works very well for me. I have some pretty small bees and really nice frames of comb. The mites still seem to like it, so I fog them with FGMO and Thymol Crystals, once a week. I can almost hear them hitting the bottom board.

Rusty

I absolutely agree. Although beekeepers have different ways of treating mites, if you do nothing you will eventually lose your bees to a mite-transmitted disease.

Keith

So, I would guess like you do, that Mortimer Wilson is in a dream or living a myth since 2003 up until 2011. How can this be? He is succeeding using small cell comb for 8 years and claims success over Varroa, he must be daffy along with all the others using small cell combs to control Varroa.

Phillip

I got into foundationless frames partially because I read about how natural cell size helps reduced mites and other diseases. Even if it’s not true, I love the look of foundationless comb as it’s being built and I’m glad I went down that path. And the bees seem to like it, so that’s good enough for me.

As for small cells reducing mite populations, I hope I never know. We don’t have mites in Newfoundland (yet). I recently read that Australia is being invaded by Asian honey bees and the mites that come with them, and apparently there’s nothing they can do about it. Bad news for a lot of commercial beekeepers, including those in the US who rely heavily on Australian imports to save their pollination colonies.

Rusty

Phillip,

I actually believe that natural cell size reduces mites and other diseases, I just don’t think it eliminates them. Natural-sized cells produce natural-sized bees, and that’s got to be a good thing.

You’re fortunate not to have mites. You should do anything in your power to keep it that way. Give the young ones a curfew and a cell phone before they get into trouble.

Bill Castro

The Asian bee invasion that Phillip speaks of is a tremendous problem for Australian keepers. Asian bees carry tropilaelaps, which are similar to varroa, but smaller and much worse. Their incubation period is shorter making the proliferation of tropilaelaps a huge problem. The Asian bee also has a robbing personality and they seem to raid European bee nests dry. If the tropilaelaps are able to come to the USA, we will see a major collapse of the beekeeping industry that will dwarf what happened when varroa made its arrival here . . . LETS STOP IMPORTING BEES!!!!

Ed. note: see Tropilaelaps clareae: another scary creature for bees

Doug

I too believe that natural cell is a good thing. I think it reduces mite levels to some extent, since I don’t seem to have mite problems as bad a some of my friends that use large foundation. I just don’t think it is a cure all, probably far from it. Natural cell, leaving plenty of honey in the hives for the bees, and less industrial agricultural forage, and more natural meadow forage is my plan for healthy bees. Most of my bees are heading for the mountains this summer. I tried alfalfa fields and other crops in heavy agricultural areas. Too many piles of dead bees. Now that we know the people in charge of protecting the environment are actually in bed with the people bent on destroying it, we have to protect ourselves. A different approach now, to create a new and different niche, outside of the machine.

Will in Sydney

Hi Phillip, Rusty, et al.

Just thought I’d add something about the occurrence of Asian bees (Apis cerana) in Australia.

It’s true that A. cerana (Java strain) have been found in far northern Australia (Queensland) after arriving in a boat mast in Cairns harbour, May 2007. So far, A. cerana swarms destroyed and examined in Queensland have not been infected with any Varroa [http://www.honeybee.org.au/pdf/Asianbeeeradication.pdf].

A worrying fact is that A. cerana in Papua New Guinea coexists with two kinds of Varroa mites, V. destructor and V. jacobsoni . . . although there seems to be some debate in the literature about the phylogenetics of these two mites. Maybe they are just variants of the same Varroa species.

In addition, V. destructor has been present in our other neighbourning country, New Zealand since 2000. It seems it is only a matter of time before it’s observed in Australian hives.

It does not however seem currently present in Australia. For regular (quarterly) updates about this, please check the Australian Animal Health Surveillance Quarterly Reports. [http://www.animalhealthaustralia.com.au/aahc/programs/adsp/nahis/ahsq.cfm]

AAHS have set up a National Sentinel Hive Program to monitor bee diseases and parasites in all states. From the Q4 report for 2010, there were 8 investigations after possible reports of Varroa from sentinel hives in the state of Victoria. All 3 were false. That’s the current news.

Regards from a sunny Sydney!

António Hermenegildo

Hello!

There is no doubt that small cell foundation although it may reduce the incidence of diseases, will not eliminate varroa, nor its consequences.

In Portugal there is a kind of traditional hive called “cortiço” that is made of the outer layer of the trunk or branches of the tree “Quercus Suber”. They do not use foundation, but only natural comb. After the introduction of varroa, in the 80`s, all those that were not treated, died after three or four years.

My best regards,
António.

Rusty

Interesting information, António. Thank you. There is much to be gained from observing the bees in different parts of the world. This is a good example.

Oscar

Great Discussion!

Only seems reasonable if bees become smaller via smaller cell size, mites can do likewise.

However, based on my very limited (!) understanding, mites strongly prefer drone cells presumably for 2 reasons: more space AND more lengthy incubation period.

A primary argument for small cell is reduced incubation time . . . small cell brood is said to be emerging between 2-3 days sooner than large cell. Small cell advocates argue that this, coupled with hygienic behavior breeding, eliminates the need for routine treatment. They strongly recommend continued monitoring and treatment of the colonies displaying a problem, which they say are precious few.

My question is “where’s the science?” Historically the science process has often taken quite some time to produce information. I suggest we do what we can to advocate the process get into high gear on this subject and the world wide wax “contamination” subject.

SoMDBeekeeper

Well, I can’t help myself. I gotta chime in on this one for a second :) I read the study and I respect the researchers however I have a huge problem with how this study was conducted. I understand, fully, the scientific method. But, sometimes nature just doesn’t play by the rigid rules that have to be followed to produce a “Scientific Paper.” I could pick apart their research line by line but I won’t bore you with that. Instead I will quote one line only; “In August 2006, bees were collected from a variety of existing colonies (irrespective of rearing history) and combined in large cages to achieve a homogeneous mixture of bees and Varroa mites….”

SAY WHAT!?!?!?

Can anyone else see why this detail alone makes the entire study a joke? Also, take a look at where the funding for the study came from. Ok, ’nuff said.

I liken the varroa mite to the black plague that swept through Europe years and years ago. It killed a lot of people. But the people that survived carried on a gene that made their offspring “immune” to the plague.

Now imagine if they had some treatment back then that didn’t cure the plague, but instead it managed the symptoms. Well, the people selling the stuff would be rich and it would have taken a LOT longer for the plague to go away wouldn’t it?

That’s how I see the Honeybee industry right now. We have big business out there selling “silver bullets” and getting rich off of beekeepers. Meanwhile the bees are still dying, albeit slower, but never getting past their problems genetically.

I say go treatment-free and make splits off the survivors and so on. We need bees that can fix their own problems and survive in spite of their “keepers” and the current onslaught of pests and diseases =)

Just my $0.02

Cheers,
SoMDBeekeeper

Rusty

When the honey bee genome was mapped, researchers were amazed to find that honey bees don’t have near the number of genes that confer immunity to pests, diseases, and toxins that other insects have. Insects like mosquitoes and cockroaches–even fruit flies–have vast numbers of these genes that allow them to quickly and efficiently build up immunity to everything from parasites to insecticides. Honey bees have very few of these genes and that is why breeding resistant bees is very difficult and very little has come from it. Obviously, breeding would be the best solution, and if it were that easy it would already be done.

By the way, anyone can pick apart a research paper. The real skill is in designing a better scientific protocol. Be my guest.

beeman2009

Rusty,

You are right, anyone can pick apart a research paper, but I would like to quote you if I may, “The real skill is in designing a better scientific protocol. Be my guest.” I would submit to you that the real skill is to leave the bees alone!!!! Let them do what they know how to do and have been doing since their beginning. I would also like to point out that “scientific protocol” as you put it is partly to blame for the mess we have now or would you deny what folks like A.I. Root did to the honeybee? Now I’m not saying that mites would never have been a problem if the bees were left alone anymore than you can say that small cell absolutely does not work. I have been small cell & chemical free since I started in 2008 and if the live testimony of people who are doing what you say does not work isn’t good enough for you, then you are closed minded and will never allow anything or anyone to stand on their own merit.

I don’t mean to be argumentative, but the scientific track record on many things has fallen far short of the hoped for effect. Could it be that enlarging the honeybee & the use of chemicals in the hive fall into this category? Guess no one will ever know!

beeman2009

Rusty

I am a scientist; I believe in the scientific method and verification using statistical analysis. I make no apology for this. The fact remains that paper after published paper has found no statistically significant correlation between small-cell bees and varroa mite populations. Most of the these papers are available online where anyone can read and evaluate them. Several new ones have come out since I wrote that post.

The difference between what a lot of hobbyists are claiming to see and what the researchers are finding probably lies within the exogenous variables, that is, variables that are not controlled or not taken into consideration by the hobbyists. These could be anything including the geographical location of the hives, the food sources, the ambient pesticide load, the competing insects, the water source, the hive dimensions, the feeding regimen, the type of supplements given, the orientation of the hive, the structural materials in the hive, the local gene pool of the bees, the local gene pool of the mites. Truly the list is endless.

To prove otherwise, hobbyists would need to do controlled studies in their own apiaries where they treat all their hives exactly alike except some would be small cell and some would be pre-stamped foundation. Once results are achieved the numbers would have to be analyzed statistically to see if the differences are within normal stochastic variability or if they are truly significant (where p < 0.05). This is another tricky step.

When an individual makes a claim such as yours, we call that anecdotal evidence. It is interesting and it may be a starting point for further research, but it doesn't prove anything because we can't tell if it is the small-cell causing the effect or something else you are doing. The various factors can't be separated from each other. That is why scientists do controlled experimentation where they hold as many factors as possible constant and just change the one they are studying.

Finally your comment, "the scientific track record on many things has fallen far short of the hoped for effect" shows a lack of understanding of the scientific method. Pure science doesn't hope for one outcome or another. A good scientist looks at a question, designs an experiment, and looks at the outcome. The result is what it is.

Bill Castro

Hello all, I like this subject and I have some good experience with small cell (SC). I use SC exclusively in all the brood supers of every hive. My reasoning is that it can only help the bees with their daily culling of brood by detecting which cells are infested with varroa. I also believe that SC brood can have a shorter incubation period, thus disrupting the varroa life cycle. This also will drive the varroa towards the drone combs to allow for much easier culling of infected drone brood. I run mostly Russian bees and every spring I see the same thing . . . lots of drone brood being culled out and flown away. My apiary, consisting of several yards, all have low mite drop counts. I do use some foundation in the honey supers, but mostly go foundationless. I extract all foundation and foundationless and make some comb honey.

I have met and spoken with Dee Lusby on several occasions in great detail about her research and findings with SC. I don’t think that SC will “eliminate” the varroa problems bees face. But I do think it gives the bees an advantage, however small, to get a handle on infested brood cells and culling that brood to prevent further infestation and possible infection with DWV. Besides, giving our bees any advantage to stay a healthy productive colony is worth it . . . NO???

Sergey

I am new at this forum and in beekeeping. This forum is fantastic! I spent quite a bit of time “researching” the Internet for more natural ways of beekeeping. It is my understanding that varroa mites are naturally occurring in beehives and mainly parasitize drones. With bigger cell size, bees get bigger and varroa start attacking not only drones but working bees and THIS creates a problem.

Returning to natural cells should eventually return varroa under control with the condition that everybody will switch to natural cells and practice natural beekeeping. As far as I do understand, there are two aspects of varroa control: natural cells (keep varroa from working bees) and space between frames. From what I read, industrial beekeepers were not only instrumental in changing cell size for their benefit but also reduced the space between frames, which creates crowded conditions [enabling] parasites to travel from bee to bee spreading the infestation.

Based on my readings, for amateur beekeeping it is reasonably easy to control varroa following simple steps: (1) use foundationless frames to have natural cells; (2) use 8 frames in 10-frames box; (3) use bottom screen for better ventilation and varroa control.

I am utilizing these conditions for 6 months and quite happy with results: foundationless frames with bigger space between them works great — no crossings at all, honeycomb is straight and much thicker than in frames with foundation; screen prevents mites from re-entering the hive and also provides necessary air flow control in the beehive. The additional benefit of such a setup . . . is they have at least 30% more honey, they are thicker.

Therel Utsey

I would like for you to give me some information on the small hive beetles. Is there a trap of some kind I could build or what can I do? I live near Charleston, South Carolina. Also one of my hives just swarmed. What should I do? Do I need to look in the hive? If so, how long before I go in? Thank you. I really enjoy reading all the information you put on the web . Thanks, Therel. I have three hives and I want to increase the number to about ten.

Rusty

Therel,

There are many kinds of plastic beetle traps available that fit in the hive and are usually filled with vegetable oil. They are very inexpensive so you can probably buy them cheaper than you can make them. Try the website at Brushy Mountain Bee Farm. They are close to you.

After your hive swarms you need to check to see that a new queen is replacing the old one. It will take awhile for the new queen to hatch, mature, mate, and start laying eggs. You should see some evidence of egg-laying within two to three weeks. If no eggs are showing up by then you will have to provide the hive with eggs and/or very young larvae, a swarm cell, a virgin queen, or a mated queen.

shelby

Back to small cell for a moment. I seem to remember one benefit being resistance to tracheal mites due to smaller bee.

bill castro

The upsizing of cell sizes done at the turn of the century resulted in many issues including the advancement of tracheal mites and eventually the perfect storm for varroa and brood diseases. If a colony is put on small cell foundation (SC) and allowed to regress through the season, that same colony will eventually no longer be pulling large sized cells for brood rearing. Most times bees will be pulling larger cell sizes for drones and honey stores while worker cells will be much smaller than modern conventional commercial foundations. Regression takes more than 1 season to accomplish, but with sincere patience and good management we can have bees that require nothing more than seasonal checks, splits for propagating, and harvesting the honey.

Sarah

When I was watching my honeybees on the bush honeysuckles this spring some seemed to be smaller than others. Can their size vary or am I imagining things?

Rusty

Sarah,

Yes. Size, coloring and lots of other things can vary. Remember that sister bees have the same mother but a variety of fathers.

Jim Whatley

Down here in Texas there’s a bee company called Bee Weaver. They were losing the mite battle by using chemicals and decided to let nature take its course. The bees that survived naturally were then used to breed their new colonies. They seem to be having great success for several years now without chemicals. It is true that their mite-resistant bee may be a little ‘hotter’ temperament due to Africanized influence. The honey production has been outstanding. I have a colony of their bees and although you do need your protective gear to work the hive, the bees don’t seem to notice me standing within a few feet of the hive.

I allowed my colony to build their own comb and am not using chemicals . . . we’ll see???

Rakesh

We have thought about bees but we need to do more research. We live in a subdivision and we are not sure how our neighbors would feel about it.

Aram

Bee Wrangler has done a few experiments with small cell. His conclusion was that 40 percent should be small cell, 40-50% larger cell, and 10-20% drone cell. I might be a little off on percentages, but I believe I am pretty close. In the fall/winter the center frames with small cells will be used to raise small cell bees, as the growing season proceeds and bees move to the periphery, they use large cells for summer bees. Larger bees are just a bit more efficient at nectar gathering. The drone cells will be used for drones and honey storage as needed. The most interesting finding was that bees will be larger in the summer regardless of the cell size. They just get better fed. All-small-cell hives are nearly impossible to maintain if one gets larger than a 5 frame nuc. They rework the frames for drones. Drones are such a cheap propagation method, and each worker’s genetic make up will have an equal chance of being spread out. With only 1 or 2 swarms per year, the virgin queen is unlikely to be a full sister to any worker bee.

Jim Whatley

According to ‘unscientific’ studies, it is said the mites are not necessarily reduced simply by cell or bee size. The positive results are gained by smaller bees being more vigorous in cleaning themselves (and others) of the mites and the mites fall harmlessly out the bottom of the hive. I would enjoy hearing other thoughts along (pro/con) about this theory.

Troy

I wish people would comment with an understanding between correlation and causality.

Varroa mites may correlate to early 20th century larger bees, but so does growth of automobiles and paved roads.

The question is one of causality: did bigger bees cause more ailments or not?

Until I see data that supports that, I believe that cars are equally likely to have caused bee disease increases over the past century.

Andrey

I’m not sure why Rusty talked about the size of the bees and squeezing of the mites in the article. Why don’t you be more open minded about it? What about the fact that the longer the the pupa stays in the cell the more mites will form? The sooner the pupa comes out the less mites are on it!

Rusty

Andrey,

I wrote about the size of bees and the squeezing of mites because that is the subject of my post.

Mike

Hello Rusty,

I’m a new beekeeper. my hive is from last summer. It is very strong, but I don’t think I had much to do with that. I have the hive for pollination on my farm. I have cherry, plums, pears, apples for fruits that I’m testing for compatibility where I live in Quebec, Canada. So, a few years ago I was dismayed to see the Japanese beetle in my fields attacking all my fruit plants.

I tried many homemade brews from the net but those that seemed to work, worked well on my plants as well! I do my own chipping and put some around my small cherry plants to control grass. Well, I have not had a Japanese beetle since, and that”s two years now. My hive is raised about 18 inches above ground and I spread wood chips on the ground. I don’t have any mites, not one and I’ve been looking since Christmas. Since this costs little to try I thought I might share this for everyone and see if this helps any.

Jim Whatley

Mike, could you share what type of wood you used for chips??? Or was it just a mixture of whatever. We have primarily juniper, oak, & mesquite.

Mike

Hello Jim,

It was a mix from the fence line but poplar was one. One other thing, the hive is along a machine shed made of cedar.