# Seeley Lab Study: Small cavities and frequent swarms, primary resistance to mites



## max2 (Dec 24, 2009)

"Colonies in small hives swarmed more often, had lower Varroa infestation rates, had less disease, and had higher survival compared to colonies in large hives.

and one would assume had lower production?


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## enjambres (Jun 30, 2013)

A thoughtful reader could conclude that the long-term survival of feral colonies was primarily related to factors other than any genetic changes in the bees themselves. Which would call into question the popular idea that one could somehow capture this survival-success by incorporating feral bees in your apiary's genetic profile. Or that Bond-style experiments would be either successful, or meaningful, at least in terms of the bees' developing any heritable trait that would give them protection from the ravages of V. dest.

Enj.


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## K Wieland (Sep 15, 2011)

I, too wonder about the honey production. The only mention is the 200kg harvested from the large hives. No honey was taken from the small hives? Too bad data wasn't taken of hive weight so that swarms could be tied to individual hives. I have seen some pretty cool data on hive weight.

I wonder if this relates to the overwintering in nucs that seems to work well.


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## Kamon A. Reynolds (Apr 15, 2012)

This is why I beleive treatment free can be done but not on a profitable scale. Anyone can split bees and sell stock (and mites)

To produce large honey crops of 100lbs plus and keep bees strong for pollination without treatment is something else.


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## Dubhe (Jul 19, 2007)

I have to question the validity of this study. It's comparing apples with oranges by mixing cavity size and swarm prevention manipulations. I believe the results would be more meaningful if cavity size alone were compared and stocking both sets with bees from the same line.


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## warrior (Nov 21, 2005)

I would say you're right. My experience with ferals is that when moved into standard equipment and managed for production, large cavity, they crash from mites.


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## Nabber86 (Apr 15, 2009)

From the bees perspective, small colonies and frequent swarming are keeping the species alive. As long as they have enough honey stores to survive, they couldn't care less how productive they are for our needs.


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## Dubhe (Jul 19, 2007)

Exactly, that's why AHB are as successful as they are. But their tendency for throwing large numbers of swarms is likely their successful strategy, not their chosen cavity space. A study could be designed to see if small cavity space correlates with increased swarm rates (very likely), but it would compare small with unmanipulated large space hives.


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## wfarler (Jul 9, 2003)

Seeley does good work. His paper on Cell Size is one of the best attempts to quantify whether or not small cells actually are responsible for reduced varroa populations. He concluded no. He looked at the most hypothesized reasons - emergence time, room for the varroa larvae to feed and grow, level of brood food. Nothing checked out and the results from the test hives were pretty much the same.

That suggests to me that something else is at play when the organic small cell beeks become successful at going without treatments. Seeley set out to look for the other mechanisms. His CV says he is currently pursuing 3 hypotheses - Varroa in the wild evolved, Feral colonies evolved or the Wild Cavity had something to do with it. I assume this study is about the cavity conditions.

Interestingly, many organic beeks are strong believers in walk away splits which leaves one colony broodless. We know a break in the brood cycle interrupts varroa life cycle.

Spivak showed that hygienic behavior does exist and can be selected. Hygienic bees tear out infested brood thus destroying the varroa larvae. It is possible that organic beeks are inadvertently selecting for hygienic behaviour.

Some organic beeks have reported faster emergence time which can reduce the number of varroa larvae that successfully emerge (they have to finish pupating before the bee emerges or they die). These beeks attribute this to small cell but it is possible that once again they are inadvertently selecting for shorter emergence time by going treatment free and using survivor stock. If either of these conditions are true it would be a case of mistaking correlation for causation.


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## Nabber86 (Apr 15, 2009)

I think that it pretty obvious that if a colony uses up it's space, the colony is going to swarm. Smaller space = more swarming. That's why we open up the brood nest in the spring and don't let the queen get honey bound.


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## lharder (Mar 21, 2015)

The missing context in this discussion is the genetic bottleneck Arnot Forest bees have gone through when varroa came through. We KNOW that genetic adaptation has taken place. This may explain why feral bees have an advantage with early survival, however surviving year to year is only a starting point. Inter colony competition means that reproductive success depends on handling pests and disease better than its neighbors. The big cavity is the big prize. Take and hold it and you dominate the local genetic neighborhood. 

Remember each piece of research is only part of the puzzle. Rarely does one piece of research explain in itself what is going on. Especially in a subject as complicated as host/pest/disease/symbiont relationships in widely differing environments.


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## Phoebee (Jan 29, 2014)

Every time this discussion comes up, I start wondering about the other side of the equation. One poster mentioned that people wind up "selling mites" along with their bees.

No doubt. As was explained to me here while I was waiting for our first two nucs, they ALL have mites. Maybe now you can get treated packages that don't, but the soon will, unless you live on an island.

But what keeps bugging me about attempts to breed mite-resistant bees is that bees raise a new queen every couple of years, while mites raise, what, 20 generations a year? So breeding mites might actually be a quicker solution. Due to their incestuous reproductive behavior, they don't actually crossbreed much. Supposedly, _V. jacobson_i is far less a problem that _V. destructor_. And this has had me wondering if the success of some TF beekeepers in their own apiaries, that fails to be reproduced at other apiaries, is due to the strain of mites they have, and not their bees. Distinguishing the two species takes gene sequencing. I estimate the number of people in this forum with gene sequencing equipment to be somewhere between 0 and 2. We don't know which ones we have.

How many feral or domesticated survivor colonies have been analyzed to see which species of mite they carry?

Have there been any studies on crowding out _destructor_ by near extermination (summer treatment with formic acid to kill the majority, winter broodless treatment with OAV to kill the survivors), followed by introduction of less dangerous mites? I'm not saying this would be THE solution, but I think the study would be informative.


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## wildbranch2007 (Dec 3, 2008)

Nabber86 said:


> As long as they have enough honey stores to survive, they couldn't care less how productive they are for our needs.


traitors they bee


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## Michael Bush (Aug 2, 2002)

>How many feral or domesticated survivor colonies have been analyzed to see which species of mite they carry?

In North America and almost all of the rest of the world the Varroa they are dealing with are Varroa destructor. The jacobsoni designation that was in common use has been replaced with "destructor" (as of the year 2000) for what is common in the world now, due to mDNA testing.

http://www.theviable.de/2011/10/27/how-varroa-became-destructor-the-story-of-a-name/
https://en.wikipedia.org/wiki/Varroa_jacobsoni
https://en.wikipedia.org/wiki/Varroa_destructor

>Have there been any studies on crowding out destructor

I can't seem to verify it with several sources, but my understanding is that V. jacobsoni only infests A. cerana. All of the Varroa that are in North America (and pretty much everywhere on A. mellifera) are V. destructor.

http://link.springer.com/article/10.1023/A:1006456720416#page-1

"Other studies reported here also show that only two of the 18 different haplotypes concealed within the complex of mites infesting A. cerana have become pests of A. mellifera worldwide. Both belong to V. destructor, and they are not V. jacobsoni."


Here is a study on both types on cerana:
https://hal.archives-ouvertes.fr/hal-00892174/


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## JWChesnut (Jul 31, 2013)

Phoebee said:


> E Supposedly, _V. jacobson_i is far less a problem that _V. destructor_.


There are several regional variants of V. destructor. The worldwide pest is the Korean mitotype. The Japanese mitotype was introduced to Brazil, and according to studies there was less destructive, but was replaced by the more fecund Korean strain.

Last year, a mDNA/DNA study found in Vietnam the strains of V. destructor inhabiting domestic A. mellifera and inhabiting wild A. cerana were different and (apparently) did not interbreed.

Studies in Hawaii, New Zealand, and northern Scotland (all on the invasion front of Varroa) have demonstrated that the Virus DWV selects for highest virulence in the presence of Varroa.

The oft-repeated meme that Varroa will evolve to less destructive forms to "restore the balance of nature" is a pernicious example of the "peaceable kingdom" fallacy. A virulent DWV (the actual killer) has strong evolutionary inertia to maintain virulence because its mode of reproduction is horizontal (hive to hive) transmission. 

I speculate that the Korean strain of Varroa was selected for virulence due to the prescence of an "invasive" species -- the introduction of European bees. Survival in nature is always relative, and if you die slightly less slowly than your competitor, you are "successful". A. cerana swarms 6x or greater per year (indicating the natural death rate is enormous). This swarm tendency indicates strong competition for nest cavity and forage, and a high colony failure rate. Introduce a competitor, and A. cerana would have an evolutionary incentive to harbor a more virulent version of its parasite. A virulent parasite that eliminates competition is an evolutionary win for the put-upon host of the parasite. The virulence co-evolved with the interaction of the invasive A. mellifera and the resident A. cerana.


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## Dubhe (Jul 19, 2007)

JWChesnut said:


> A virulent parasite that eliminates competition is an evolutionary win for the put-upon host of the parasite. The virulence co-evolved with the interaction of the invasive A. mellifera and the resident A. cerana.


Now that's a fascinating way to look at evolutionary benefits of virulence, and thank you for explaining it so clearly. A question: peaceable kingdom fallacy notwithstanding, do you think that the benefit of virulence might change in areas that don't harbor A. cerana?


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## Phoebee (Jan 29, 2014)

JWChesnut said:


> The oft-repeated meme that Varroa will evolve to less destructive forms to "restore the balance of nature" is a pernicious example of the "peaceable kingdom" fallacy. A virulent DWV (the actual killer) has strong evolutionary inertia to maintain virulence because its mode of reproduction is horizontal (hive to hive) transmission.


We've had this conversation before. And again, I will point out that the reason DWV and other viruses can get away with this horizontal transmission avarice is that we keep giving them more hives to infect. If this were in nature, they would kill hives until they isolated themselves, and then die out. Possibly that would be an extinction event for honeybees, but it would also be the last of the virulent virus, unless it could find another host.

But in apiaries where humans are scrambling to replace losses, the virus may spread with abandon. If, better yet, the bees are loaded on to trucks and taken to a central point every year, where viruses may be freely exchanged, so much the better for the virus. Modern beekeeping is pointedly not nature, it is a managed livestock situation.

Hospitals have much the same effect with humans.

So we created this and we have to deal with it. And it is why I'm IPM, not TF. But hopeful.


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## lharder (Mar 21, 2015)

Vectors and virulence is only part of the story. Ectoparasites are ubiquitous and according to this theory social critters especially should have been wiped out by diseases carried by them. The black death had a horrendous effect on Europe, but it didn't wipe it out. Not even close. Its not that the theory isn't useful, its just not a complete explanation.


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## Dubhe (Jul 19, 2007)

Agreed, for sure. We're at the beginning stages of understanding the role of the microbiome and how it relates to survival. The line between good guys and bad guys is not so clear cut it seems, and evolution is relentlessly efficient. As beekeepers, we're trying to maintain a static balance of an organism and its environment to suit our specific purpose, but Mother Nature will never really let that happen.


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## JWChesnut (Jul 31, 2013)

Phoebee said:


> We've had this conversation before. And again, I will point out that the reason DWV and other viruses can get away with this horizontal transmission avarice is that we keep giving them more hives to infect. If this were in nature, they would kill hives until they isolated themselves, and then die out.


Yours is a speculative claim, representative of the Aristotelian logic that seems to have infected beekeepers. 

Real world science has studied DWV in the wild highlands of north western Scotland, along an invasion front on the tip of the South Island New Zealand, and on Big Island Hawaii. At none of these sites are there a plethora of "evil commercial beekeepers" messing with the "natural harmonious balance of nature". 

Horizontal transmission of disease is an effective, evolved mode of transmission, selected by organisms for its utility. It is not some aberrant freak created by unthinking capitalists of the modern age. 

Could honeybee distribution respond to DWV? Of course, and widely scattered, and quickly ephemeral hives would be an obvious coping mechanism. Not a pattern conducive to human harvest.


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## Phoebee (Jan 29, 2014)

JWChesnut said:


> Yours is a speculative claim, representative of the Aristotelian logic that seems to have infected beekeepers.
> 
> Real world science has studied DWV in the wild highlands of north western Scotland, along an invasion front on the tip of the South Island New Zealand, and on Big Island Hawaii. At none of these sites are there a plethora of "evil commercial beekeepers" messing with the "natural harmonious balance of nature".
> 
> ...


Where did I say beekeepers were evil? I'm one and I treat. I wish I didn't have to, but I'm a realist.

I don't know what makes my logic Aristotelian. Am I to suppose that Aristotle was illogical? Unscientific, perhaps, but nothing like at twisted as the Pythagoreans. 

But let's look at the history of this problem. First, _Apis mellifera_ is not in North America by an act of nature. We brought 'em. And _Varroa_ didn't walk here either. And the conditions under which bees are being kept are apiaries, not wild or feral hives widely spaced in trees about the countryside. So mites and diseases they carry with a penchant for "horizontal transmission" don't have far to go. We create ideal conditions for this, and we replace colonies as fast as they succumb.

This is a manmade problem and we get to deal with it. Not by vilifying each other, but by trying to find the best way out of this mess. And since it is a complex problem, that means more than one strategy. Will we have to treat forever, or will we somehow find a natural control?

I have no anwswer. Just questions and hopes. 

On the way home from our apiary today, we noticed the outyard several miles from us, not populated last year, now has its former complement of hives, fresh off the almonds. Good news/bad news. Lord knows what viruses came with them, but I do know they will have some diversity of locally-adapted genes carried by their drones. Last year we would have been skunked on mating opportunities had we not scored the nuc of Russians just in time, because the outyard was not there to provide mates for the queens we were raising from our one surviving hive. 

Will we threaten the commercial hives with a mite bomb? Rather unlikely. Yesterday I spotted a total of one mite on the IPM board of the Russians. The main VSH hive got a dose of OAV in January and is as close to clean as they come. The two nucs are also in good shape. Next week all the bees will get together on the Autumn Olive between the two apiaries and all that will change.


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## Nabber86 (Apr 15, 2009)

JWChesnut said:


> Horizontal transmission of disease is an effective, evolved mode of transmission, selected by organisms for its utility. t.


Apollogies for for being somewhat pedantic, but organisms don't _select_ traits. 

I think Socrates may have said that. opcorn:


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## wfarler (Jul 9, 2003)

For varroa and bees to naturally evolve to a point of balance the bee population would have to collapse to the point that varroa ha f difficulty finding a host. Then over a long period bees would have to evolve some mechanism to cope (like hygienic behavior) or die out.


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## sqkcrk (Dec 10, 2005)

max2 said:


> and one would assume had lower production?


I would assume so. How can you have a "small cavity and swarming" and harvestable honey? One would have to run a hive with room for that honey to be stored in, in other words, a larger than a small cavity. You can't have it both ways.


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## sqkcrk (Dec 10, 2005)

Phoebee said:


> But what keeps bugging me about attempts to breed mite-resistant bees is that bees raise a new queen every couple of years, while mites raise, what, 20 generations a year?


No, Phoebee, a colony of bees raises queens much more frequently than that. Not only annually, but often queens are replaced by a colony between swarm season and the Fall.

The frequency of the mite life cycle is what one can track to determine when best to apply a miticide.


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## lharder (Mar 21, 2015)

But what keeps bugging me about attempts to breed mite-resistant bees is that bees raise a new queen every couple of years, while mites raise, what, 20 generations a year? 

The same argument can be applied to all multicellular life, yet here we are discussing it. There is obviously more at work. Some get stuck on theories and ignore the other evidence to the contrary. There are examples of bees without treatments, even bees in large spaces clustered in apiaries. There are some places where mite/disease pressure is so extreme that comprehensive treatment programs may be needed. If horizontal transmission made high viral virulence inevitable, then this wouldn't be. Other explanations are needed. Another explanation is that it is movement of bees interregionally is creating chaotic disease dynamics.


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