Coevolution of Honey Bees and Varroa Mites: A New Paper

[mike bispham]

I think I'm with you, Solomon.

Honestly, I think letting them alone in terms of selecting for survival is all any of us are really qualified to do. There are just too many things we don't (and may never understand about the bees).

I think we must continue to select for traditional traits like temperament and production levels, as these are things that are important to our interaction with them. But in terms of survival, I think survival itself is the only trustworthy indicator.

Adam

I'm with you both on this - as an ideal. But the question was: how does a large commercial operation go over to treatment free without loss...

For myself: I source survivors, don't treat or manipulate, and don't feed. I only propagate - from the best. So my bees _are_ survivors in every sense.

One of the things I aim to do is carefully support, and definiately don't downgrade, my local breeding pool. I want feral bees around me, sending their genes inward, and I want to be able to think I understand their needs. So my bees are selected to be strong (which I think benefits the ferals) and to carry no impeding traits. They know when to build, when to raise winter bees and when to store. They are local bees tuning themselves constantly to local conditions. I haven't yet felt the need to select for temperament or quietness on the frames. (I worry - probably foolishly - that gentle bees might be more prone to robbing)

Mike

[Solomon Parker]

I'm with you both on this - as an ideal. But the question was: how does a large commercial operation go over to treatment free without loss...

If it is possible for bees to survive long term (this is a big if and I am not yet certain it can be done) then it will be done using queens produced treatment free. I believe it will also require wholesale removal of old combs as well. But it won't just be a two step thing. Queens produced treatment free will most likely come from stationary operations. The few performers that result from migratory operation must continually be recycled back into the breeding program so that a treatment-free migratory bee will be developed. But even that will result in some loss. So it's a conundrum.

[jbeshearse]

It is not really either or. Both the treatment free/feral populations and the managed populations will eventually reach the same level or mite tolerance/ resistance. It will take the treated managed populations longer to get there but they will eventually get there, just as the treatment free will. Managed treated colonies that have the necessary genes to survive untreated are not killed off or managed out. They survive better than the rest of their treated kin. The only reason it will take the treated bees longer to reach that point is that the populations are larger and the treatments mean non resistant bees will continue to survive until the treatment free gene works it's way into the entire population.

[mike bispham]

It is not really either or. Both the treatment free/feral populations and the managed populations will eventually reach the same level or mite tolerance/ resistance. It will take the treated managed populations longer to get there but they will eventually get there, just as the treatment free will.

Hi,

This is not what the science of evolutionary biology or the art of breeding foresee. Organisms adapt to their environment. An environment in which a beekeeper supplies treatments offers no selective pressure toward adaptation - in this case mite resistance. It just won't happen - unless those same beekeepers also systematically select for the best and eliminate the worst strains. That's just the way things work, and what is needed. As the paper that forms the subject of this thread states:

"Coevolution by natural selection in this system has been hindered for European honey bee hosts since apicultural practices remove the mite and consequently the selective pressures required for such a process." (Post #1 of this thread)

Managed treated colonies that have the necessary genes to survive untreated are not killed off or managed out. They survive better than the rest of their treated kin. The only reason it will take the treated bees longer to reach that point is that the populations are larger and the treatments mean non resistant bees will continue to survive until the treatment free gene works it's way into the entire population.

That's possible in most cases - because most bee populations have the necessary traits in about 10% of the individuals. But it all hinges on just what is meant by 'managed'! If they are systematically selected and propagated to promote resistant strains (and that includes keeping non-resistant strains out of the breeding pool...) then that will happen. But that's best described as 'managed toward non-treatment'.

If, to take the other extreme, they're managed by systematic treatment and/or importing of non-resistant queens, it'll never happen. The selective pressure just isn't there. Even if you started with good resistant stock you'd very soon breed the resistance right out again.

It really is 'either/or'. One consequense of that is the unfortunate corrollary: if you're not part of the solution then you're part of the problem.

Best wishes,

Mike

[mike bispham]

If it is possible for bees to survive long term (this is a big if and I am not yet certain it can be done) then it will be done using queens produced treatment free. I believe it will also require wholesale removal of old combs as well. But it won't just be a two step thing. Queens produced treatment free will most likely come from stationary operations. The few performers that result from migratory operation must continually be recycled back into the breeding program so that a treatment-free migratory bee will be developed. But even that will result in some loss. So it's a conundrum.

I think it might be worth remembering that this is all about adopting the right _process_. There isn't some endpoint where we can all relax and stop breeding purposefully. The bees, and the mites, and the viruses constantly adapt, and we must guide their evolution through selective propagation - always. This is what happens in every other field of husbandry - and must.

The possible alternative is a heathly feral population in which nature does the breeding for us. (Note many livestock animals are constantly refreshed by the injection of wild or semi-wild stock. In the UK most breeding sheep are first crosses of 'hefted' upland (mountain) flocks - essentially survivor strains - with carefully raised lowland breeds. The same thing happens with moorland ponies.)

Such a state would not reliably supply highly productive hives - that would need further breeding. But it would go a long way to taking care of essential health. Nor would it stop occasional population crashes. These things are part of nature; populations rebuild - usually rapidly from the (resistant - and newly invigorated) survivors.

Back to my point: maintaining a population necessarly involves selective propagation. Mite resistance has to be built into the list of desirable characteristics, and selected routinely. There will never bee a once-and-for-all-time resistant strain. Management has to be about managing the ever-needed ongoing process of maintaining resistance. It needs to be done wherever bees are purposefully reproduced.

To the extent that that happens things will improve. Where it doesn't they will probably get worse. That's just nature correcting poor husbandry.

Mike

[Detroit Bees]

Ladies and Gentlemen,

I think this is a fantastic thread with many, many insightful and intelligent questions and responses and I thank you for all that I have learned so far.

Here is my uneducated point of view as a noob to bee keeping and a semi-weekend scientist:

No matter what the breeding/husbandry history of a particular "wild" animal, both good and bad traits are going to be transferred from one generation to the next. Neither man nor nature can select out just the "bad" traits and keep just the "good". What's good for my Detroit bees may be terrible for your Houston bees based on innumerable factors. So we will continue to raise "better" bees for our purpose based on those innumerable factors.

Before man tamed his first bee hive, bees did just fine in nature. Good colonies lived and died and so did the bad ones. I think that ultimately, Mother Nature will breed the best bees and, if left alone, bees will be fine no matter where they live or what other pests are thrown at them.

What we as bee keepers are faced with is breeding out our own bad traits that we bred into bees. We want bees that are docile and productive and resistant (plus more good traits) of course, but can we have all of them at once? I understand we want our cake and to eat it, but this is not nature's way. Nature breeds fighters who aren't docile...how can you have both?

I think what we as bee keepers need to do is adapt ourselves to the bees that can survive any problem thrown at them. Build a better bee suit that can protect you from aggressive bees, build a better hive to help bees be more productive, keep all the man made problems out of a bee's life so they don't have to work so hard to be resistant to chemicals, cities, pollution, etc...leave bees alone in a natural place without man's influence and they will survive and prosper just like they did for thousands of years before we came along to "keep" them.

Nature will select the best traits for the geography and topography and every other kind of "ography" you can throw at a species. However, nature doesn't live on your time line or mine...and no amount of husbandry will make it do so. This entire problem and most others are man made and now we as the small time sect, must try to reverse the bad things we have done. Bees survived just fine without us and if we leave them alone they will again...perhaps not on our timeline. We want what we want and we want it now...

As for correcting these issues, how can we do all these things? I am not so smart to have any great insight into that. This thread (and forum) has opened my eyes to many new issues both small and large scale with regards to bees and I thank you all for that.

Respectfully,

Peter

[WLC]

There are a few problems that remain:

"Mechanistic explanations of the bees’ ability to suppress
mite reproductive success remain unknown."

Until they can 'bottle' mite resistance, there's no way to make use of it.

Secondly, there have been many attempts to sell "mite resistant bees", and they generally fall flat, with the exception of hygienic bees, and they still understand only about 30% of what makes those bees hygienic.

So, while the paper demonstrates the existence of mite resistant bees that have a mechanism other than hygienic behavior, we're still where we were before.

[crofter]

Peter, I agree with your philosophy: I do question the part though, that bees always have adapted and always will if we just let them; that indeed may not be a given. In Mother's Nature, extinction of species and succession by something better suited to changing conditions, is much more common than adaptation and survival. One wrong adaptiive turn can, and has lead many species into a fatal evolutionary blind alley.

Unfortunately mans actions are responsible for most of the stressors in the adaption process, or more exactly he is directly the organism that must be defeated for others to survive. It is a leap of faith to suggest he might have the ability to wisely steer the permanent solution of the conflicts. My advice is that we should be very afraid of any simplistic solutions. Unforseen consequences can sure bite us in the butt!

[Adam Foster Collins]

There are a few problems that remain:

"Mechanistic explanations of the bees’ ability to suppress
mite reproductive success remain unknown."

Until they can 'bottle' mite resistance, there's no way to make use of it. ...So, while the paper demonstrates the existence of mite resistant bees that have a mechanism other than hygienic behavior, we're still where we were before.

That's my big problem with the whole discussion of mites. We don't actually have a solid grasp of the mite/bee relationship, and really don't understand completely the different methods a bee might employ to deal with them. So we can't really select for it specifically. And if we try, we might very well be selecting against some of them. VSH is one we know, but it might be only one of several important mite-resistant traits. How do we find the rest of them if we continue treating?

That's why I think the first selection criteria has to be survival. If you don't treat at all, and the bees survive the presence of mites and continue to winter, then the mite resistance (whatever that actually is) is "in there", so to speak. If I get a population of bees that is consistently living and thriving in the presence of mites, then don't I have "mite resistant bees"?

Isn't it possible - even likely - that we may never know the full range of the honeybee's ability to deal with mites until AFTER we have stopped treating and let her fully adjust to deal with mites on her own? And that allowing the bee to do her thing naturally, might be the only way for her to get there - that human beings may have no other way of assisting her?

Adam

[mike bispham]

I do question the part though, that bees always have adapted and always will if we just let them; that indeed may not be a given. In Mother's Nature, extinction of species and succession by something better suited to changing conditions, is much more common than adaptation and survival. One wrong adaptiive turn can, and has lead many species into a fatal evolutionary blind alley.

'Adaptation' is something that occurs in every generation. It may lead to larger changes (even new species) further down the line, or it may more or less reverse a short while - or any time later - when conditions are such that the old set up is favoured. We can say, without fear of dispute, that bees have adapted conditinuously for 20 million years or so, without changing a great deal.

This perspective forces us to challenge your statement; and indeed, to forcefully reverse it: adaptation is far far more common than extinction. As to an adaptive turn leading to a fatal evolutionary alley, I'd like to see some documented examples or references.

Furthermore such adaptaion is utterly necessary. From the first paragraph of the paper:

"Coevolutionary theories in the study of host–parasite interactions
indicate that antagonistic reciprocal selection pressures
will lead to an “arms race” with a series of adaptations
and counter-adaptations by the host and parasite (Thompson
1994)."

Unfortunately mans actions are responsible for most of the stressors in the adaption process, or more exactly he is directly the organism that must be defeated for others to survive.

Yes. In this case his action is the frustration of the essential process of adaptation - in every generation, such that the honey bee can keep up in its 'arms race' with mites. He must be defeated by... stopping this systematic frustration.

All this is key background understanding, forming the basis for the study. You rather have things back to front, and dramatically underestimate the forceful nature of scientific studies. This isn't up for argument, its fact.

It is a leap of faith to suggest he might have the ability to wisely steer the permanent solution of the conflicts. My advice is that we should be very afraid of any simplistic solutions. Unforseen consequences can sure bite us in the butt!

This is not a 'simplistic solution': its the logical application of straightfoward evolutionary biology and breeding practices, as embedded in this (and other) scientific studies, corroborated by thousands of empirical observations of bee/mite relations. It is observant of, and in agreement with, many other similar studies. It does not contradict any aspects of scientific understanding. You can take it as read - or stand pretty much alone against the body of scientific understanding of the relations between hosts and parasites generally, and the application of that understanding here.

Mike

[Adam Foster Collins]

I have to wonder how much good anyone is able to do by going treatment free, if their apiaries are within mating range of others who continue to do treatments.

How much can be accomplished if the majority of beekeepers are treating their bees?

Adam

[crofter]

Mike, I am not disputing the premise of the article. I think there are plenty of occasions where introduced species have wiped out others whose adaptive processes did not work fast enough. That is not to say that their existing mechanisms were faulty. Mans meddling or abrupt climate change can be devastating to species already in severe competition. When man has the power to change conditions so rapidly he interferes with the natural pace of things. If he makes an opps in one direction should he be allowed to make what he considers a rectifying move in the other? That is where I caution simplistic solutions. Perhaps loss of genetic material is not a consideration but I believe it will be hard for scientific man to avoid that while trying to steer the mite/bee adaptive process to include his objectives. I worry that future defensive properties may be lost in the process of dealing with the recent and current and perhaps temporary, problem of Asian mites.

I would like to think that Science is altruistic but it seems to have some skeletons in its closet and would do well to have some big picture generalists looking over the shoulder of the specialists when tinkering with mother nature. Though it would be the wisest thing to do, I dont think we have the collective will to back off and let nature take its course.

[Solomon Parker]

Until they can 'bottle' mite resistance, there's no way to make use of it.

If that's the answer you're looking for, it won't be found. You're asking to bottle something found only after throwing away the bottle. It's the same sort of concept of people who come to this forum looking for, and I quote: "treatment-free treatments."

Think outside the bottle.

[heaflaw]

I agree with Solomon. Species have successfully adapted to adverse conditions for millions of years without humans understanding the mechanisms. It would be more efficient if we understood the mechanisms and could more easily monitor them to spread them around, but I don't see why it's necessary at all.

[WLC]

Let's not forget that folks have been selling bees that they claim are mite resistant, but the claim doesn't work out even if the bees were resistant for the seller.

It generally hasn't worked when resistant bees are moved to a different environment for some very obvious reasons. The pests and pathogens in the new location are different.

For instance, if you switched the locations of the bees from Avignon, France and Gotland, Sweden, then you might find the very same thing that has been reported again and again. The resistance seems to disappear.

That being said, it's OK to try, just in case you happen to have bees that are universally mite resistant.

As for 'bottling' mite resistance, VSH is one example, maybe there are others that can be found if we bother to look.

As for the treatment-free-treatmentrs remark, I thought that we might be looking for good genetics, or something similar.

[jbeshearse]

I have to wonder how much good anyone is able to do by going treatment free, if their apiaries are within mating range of others who continue to do treatments.

How much can be accomplished if the majority of beekeepers are treating their bees?

Adam

Host/parasite relationships are almost always a cycle. As the parasite species grows to virulent, the host species declines. Until such a time that the parasite species declines to a level which allows the host species to rebound.

Treatment free or treated will have little to no effect on the overall honeybee resurgence. After the majority of feral (treatment free) colonies perished (probably 90%+), those that remained had better coping mechanisms and are slowly rebuilding populations. The managed populations are experiencing the same thing. Treatments do not kill that 10% of the managed population that would have survived anyway. The managed population may take longer to to reach the same level of hardiness as the ferals (treatment free), as those that are not adapted are treated and thus survive. In reality, treatments are an effective way to insure overall populations do not severely decline before the species rebounds on it's own. I don't think it is an either or scenario, I think both practices are working together for the good of the species.

That said, it is a cycle and eventually the parasites will overburden again and the host populations will crash.

In the referenced study, if the population of isolated bees that enjoyed success because the mites were not as successful in reproduction, were exposed to a mite population that reproduces better, two things would happen. First, the less successful mite population will die out as the more reproductive moves in (survival of the fittest). Second, the bee population would decline just as the un-isolated bees did. Unless the bees themselves are suppressing the reproductive ability of the mites.

[mike bispham]

Hi Crofter,

I agree with all you say, except that part which seems to be saying 'carry on treating, because to do otherwise risks losing genetic diversity'.

Its easy to label a proposed solution (or rather, an understanding of the mechanisms in play that can lead to solutions) 'simplistic'. But it seems to me to be a case of: give a dog a bad name and kill it'. In what way are the things here - the principles and the actions they indicate ' simplistic'? I think you make a charge with that term, and I think it requires justification.

Marla Spivak, whose method I've indicated might be of interest to large commercial operations wishes to wean their bees off the meds, makes a specifical global point along these lines: It is best for this to occur at a local level, so that genetic diversity is maintained, rather than to have central breeding operations which could easily narrow diversity alarmingly.

It isn't the case that nobody is thinking about this. And its a good point. But it isn't a reason to do nothing - to carry on with the meds.

There is ample evidence showing that where bees are able to be free of treatments their natural defences are bought to the surface by natural selection, and the age-old problem of a new introduced parasite is taken care of. In what way can that be said to be simplistic, or meddling?

I think 'backing off and letting nature take its course' is precisely what many of us are willing to do - on a local basis - and that the evidence we will provide will strengthen the diagnosis: the biggest health problem bees face is addiction to meds.

Mike

[mike bispham]

If that's the answer you're looking for, it won't be found. You're asking to bottle something found only after throwing away the bottle. It's the same sort of concept of people who come to this forum looking for, and I quote: "treatment-free treatments."

Think outside the bottle.

I'm not so sure. To build selection against mite-vunerability into your management system seems to me to be bottling it. What you have to sell is the understanding: the selective propagation process is the key. (If you can, start with stock that gives you a fighting chance)

Mike

[mike bispham]

Until such a time that the parasite species declines to a level which allows the host species to rebound.

What you mean is 'until such time that the host-parasite pair reach an accomodation that allows both to rebound.' From there on those hosts better at reducing the effect of the parasite will prosper at the expense of those less well able to control them.

Treatment free or treated will have little to no effect on the overall honeybee resurgence.

This is inconsistent with the stand taken in the paper; to the effect: it is treatments that prevent the co-evolution of host and parasite (and virus).

After the majority of feral (treatment free) colonies perished (probably 90%+), those that remained had better coping mechanisms and are slowly rebuilding populations.

Where they are free of the influence of treated drones the rebuilding is rapid

The managed populations are experiencing the same thing.

They are? What is your evidence for this claim?

Treatments do not kill that 10% of the managed population that would have survived anyway.

No, but they do allow the other 90% to reproduce freely. That prevents adptation. Entirely. If you subjested a 'survivor' population to the same regime, within a few years they'd be equally vulnerable.

The managed population may take longer to to reach the same level of hardiness as the ferals (treatment free), as those that are not adapted are treated and thus survive.

It isn't a case of taking longer. It will never happen because (as the paper reminds us) selective pressure is removed by treating.

In reality, treatments are an effective way to insure overall populations do not severely decline before the species rebounds on it's own.

There is absolutely no evidence that this is the case, and it flies in the face of fundamental evolutionary biology. It directly contradicts the clear statements, made by the authors.

Bees have a natural defence mechanism - shared by all living things: die-back to resistant strains: rebuild from resistant strains. This process carries no cost in terms of diversity.

Treatments frustrate that process entirely, and on an ongoing basis. Treating corrodes diversity by preventing the re-emergence of feral bees around apiaries.

I don't think it is an either or scenario, I think both practices are working together for the good of the species.

To think is easy. To make a convincing case you'll need to show where evolutionary biology is going wrong - and write a clear account. I don't think that will be so easy.

In the referenced study, if the population of isolated bees that enjoyed success because the mites were not as successful in reproduction, were exposed to a mite population that reproduces better, two things would happen. First, the less successful mite population will die out as the more reproductive moves in (survival of the fittest). Second, the bee population would decline just as the un-isolated bees did. Unless the bees themselves are suppressing the reproductive ability of the mites.

I think there is a measure of truth in this. The co-evolution, the study shows us, is local, and there is no reason to think either offers universal protection. With that said, both strains, with their separate defence mechanisms, would offer at least some protection against highly fecund mites. It would be interesting to see if one did more than another.

Mike

[mike bispham]

I have to wonder how much good anyone is able to do by going treatment free, if their apiaries are within mating range of others who continue to do treatments.

How much can be accomplished if the majority of beekeepers are treating their bees?

This is highly relevant. I think the best strategy is to try to swamp your local breeding pool with good drones. Forming local breeding clubs is one route, large self-suffiencient hives on outstands at a bit of a distance another. Keeping away from large treating apiaries a third. Having lots of hives is much better than just a few - I think my hives probably outnumber those treating within drone range. Be among survivor feral colonies. Those are my strategies anyway.

I think that largeness in bee colonies is very indicative of success and influence. Very big colonies tend to produce large drone populations, and only get that way by being well adapted to the environment. And drones carry a copy of the queen's genes - if she's a good-un they are a powerful transmitter of her genes - twice as much as ordinary - proper - males.

I think that competitive mating is a powerful mechanism for adaptive health in bees as other species. The largest generally win the mating competition, and the same underlying evolutionary driver that sees big males mating with the majority of females in many mammal species (through harem arrangements) works too with big bee colonies. For that reason my mating outstand drone hives will be unlimited brood nest colonies, made from my best.

Mike