Bees are starting to evolve to survive destructive varroa mite, researcher

http://www.beeculture.com/catch-buzz-bees-starting-evolve-survive-destructive-varroa-mite-researcher-says/
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By: Robin McConchie

Bees in the United States and Europe are starting to evolve through natural selection to survive a mite that has been decimating their populations.

Professor Stephen Martin, chair of animal ecology at Salford University in the United Kingdom, said in some instances bees were living with varroa mites and an associated virus, without any other treatment.

“We are trying to understand what is happening,” he said.

Although the process of evolution is slow, it has given the industry hope and sparked an interest in better beekeeping methods, with people entering the industry to try and save the bees.

“Without the beekeepers in some areas, the honey bees would have disappeared completely,” Dr Martin said.

“One of the benefits for Australia is if we can understand what is going on, we can tell you [Australian beekeepers] what to look for, what sort of set-ups work, what treatments are needed.

“It used to be very bleak for a long time, [but] the bees are sorting themselves out.

“We just need to help the beekeepers understand how to speed up that process.”

Australia will not be immune from mite

However, Dr Martin, who was a keynote speaker at the Queensland Beekeepers Conference, also warned the devastating varroa mite would get into Australia and cause serious damage to the nation’s honey bee industry and native bee populations.

He said it was a matter of when, not if, the varroa destructor mite established itself in the country’s bee colonies.

“It is a testament to your biosecurity service that it is not here yet, but we live in a global community and, as a case in Townsville recently showed, it is just a matter of time,” Dr Martin said.

“It will just come in accidentally on a passenger or in a shipping container. You are lucky so far, but eventually it will arrive.”

Dr Martin said he would not wish the introduction of varroa on anyone.

“It has spread around the world, but it is not the complete devastation some think it might be,” he said.

Varroa spreads damaging virus

Beekeeping has not collapsed in Europe or America, but it requires a huge amount of management, more intervention, and increased use of pesticides into colonies to control the mite.

“You will suffer a large number of colony losses of up to 80 to 90 per cent initially, until people start to get used to it,” Dr Martin said.

“The other big problem is you will lose all your feral colonies as well, and [with] that free pollination disappears.

Every colony that dies breeds mites and they go back to reinfest colonies even if they have been treated.”

Dr Martin said the impact on the bees was subtle because it was usually a couple of years before the colonies started to die.

But by that time, the mite had established itself around the country.

He said while the varroa mite sucked the blood of the bee, it was the transmission of a virus into the bee that really caused the damage.

“In areas where there is no virus, the bees and the mites can live together, but this is extremely rare,” he said.

“The mite is simply the vector for the virus to get into the bee.

“In Europe and America almost every single bee has got the virus.”

Dr Martin said there had been massive colony loss in the US and Europe, and many commercial beekeepers had lost their livelihood, while hobby beekeepers had stopped keeping bees.

Compounding the problem, he said, was the fact that miticides quickly developed resistance, and the virus appeared to be impacting other pollinators.

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Great idea. Lofty hopes. Meanwhile pie in the sky while my bees die if I don’t treat. I have devastating varroa at the moment, even though I have managed for it. Destructor is the right name. :cry:

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The fellow I was doing some beekeeping with uses no chemical treatments.

He has about 80 hives here in Sicily, and is certified bio/organic.
He cuts out all the drones if there is a lot, as he says that is where the varroa likes to go.
It was a bit hard seeing him squish growing bees, and cut-out such large patches of bees/brood, but in the end it seems to work for him, and save his colonies in the long run.

He also sells the larvae to some countries. Some eat it. I remember Jeff posting a video about larvae patties.

It’s one of those things where each beekeeper has to do what they feel is right and works for them. And even then, sometimes it works, and sometimes it doesn’t :frowning: As in you case.
Ah what can ye do eh?!

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@Dawn_SD that’s awful to hear.

Although we don’t have Varroa here in West Oz I have done a fair bit of reading about various bee diseases and pests. One of the theories I read about varroa control was that using foundation on your frames makes it harder for the bees to self-control varroa (I can’t recall if the foundation in question was all types or plastic only). Although it has happened over generations and generations the theory was that bees have slowly increased in overall body size due to the use of foundation helping “fix” the size of the cell they are raised in but their legs haven’t proportionally increased. A consequence of this is the bees can’t easily ‘flick’ the mite off.

Do you use (plastic?) foundation? Any chance of progressively going to foundationless on some or all frames and seeing if that helps any (I realise it is getting late in your season…)? Obviously I can’t comment on how this might assist or even if there’s any evidence to substantiate a benefit from letting bees determine the cell size versus the foundation acting as the sizing guide.

Something else that I’ve come across (elsewhere on this forum? Google? …can’t recall) for non-chemical control is the bee gym:
http://www.vita-europe.com/products/bee-gym/

Again, I can’t comment on the reality of the the above in practice. Thankfully, it isn’t an issue I have to contend with.

EDIT: I just came across this… http://www.tandfonline.com/doi/full/10.1080/00218839.2016.1260388

Grooming is a promising area for improving V. destructor management; however, from this investigation we find no detectable effect of the Bee Gym grooming device on V. destructor removal in honey bee colonies over a 2 week period. The measures used for assessing grooming efficacy are still under debate, and it is possible that an effect could be missed, or obscured by other confounding factors. Nevertheless, to our knowledge, there is currently no evidence that bees use external objects to groom. If further work is carried out on this as a potential treatment method, we therefore suggest that a sensible initial step would be to directly test the potential of grooming devices in assays with individual bees.

Thank you. I feel bad for my bees. They will probably make it, but I estimate that the hive has lost around 40% of the population in the last month or so. The mite counts exploded from under 10 per 300 bees, to around 20 in that time. At least I have 3 hives, so I have the option of combining or even stacking them with a Snelgrove board over winter. We don’t really get a winter here, just a long nectar dearth, so the queen should keep laying and perhaps can make up the lost population.

My point is, the research is fascinating, but don’t let it make you complacent. Varroa is a huge problem, and can sneak up on your hives very quickly. Unless you have time and sufficient hives to avoid treating, treat early and be aware that treating twice per year may well not be sufficient, even with VSH bees. I have now seen that myself. :blush:

I thank AQIS and the fact I live on a very big Island. And to go further, live in the even more isolated SW corner.

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