Varroa project 2014 –>

This test is accomplished and funded by LP:s biodling bee equipement supplier, Arne Andersson sideline beekeeper and Erik Österlund sideline beekeeper.

 

GOAL FOR THE PROJECT

The goal for this test is to see if it is possible:

  • to improve mite resistance in apiaries with 5-10 colonies,
  • to understand the impact of ”isolation” of 3-5 km (3-4 miles) to other beekeepers
  • to understand the role of small cell size in the broodnest
  • to see the role of differentiated treatment of varroa mites, that is treatment of only those colonies that exceed a defined varroa level

 

PLANNED MANAGEMENT

Avoid silent robbery

The colonies should be managed as similar as possible to a beekeeper that want to increase the number of colonies with an extensive management method. It should interfere as little as possible with the bees activities and avoid disturbing parameters, which could happen when you open the colonies often, like for example starting robbing in nectar droughts. It could be enough with silent robbery, a robbery activity that you don’t notice. That could be enough to destroy a test, in that the varroa populations are evened out

3% strategy

Therefore we decided to maximize the number of hives for the two main groups in this test to 10 hives (5+5). We also decided to make two or three alcohol washes with 1 dl of bees to monitor the varroa level during the season. When the Varroa level was higher than 3% we planned to treat with thymol. If it appeared wingless bees in or in front of a hive treatment was also to be performed.

Use of thymol

We decided to use dish cloth pads drenched with fluid thymol mixed with a minimal amount of rubbing alcohol (to lower the melting point of the thymol crystals) as treatment against mites when decision was made to treat. You can see how they are done and used in this article: http://elgon.es/resistancebreeding.html

Crop and feeding

If possible a harvest should be taken and sugar solution (or honey) fed at the end of season after harvest to ensure enough food for winter. The goal should be to leave a fair amount of honey for winter, if possible as much as you think your bees have got genetics to make it through the length of your winters.

Nucs and splits

Increase are made by making so called walk away splits that remain in the same apiary as the mother colony. These are allowed make there own queens, or supplied with mature queen cells made from a good colony in the apiary. This should also be the swarm prevention method.

Elgon and Carnica/Carniolan

We choose to use two different types of bees in the project. One type that has been selected for varroa resistance during many years, Elgon, that has been bred with this purpose since 1989. Another type that hasn’t been selected less, but in other traits are good, pure bred Carnica/Carniolan bees.

 

FITNESS

Increase of the number of colonies

The number of colonies wintered each autumn would be a way to measure the difference in success between the two parts (large and small cell size) of each main group, Elgons and Carniolans. To be counted in the increase would be the colonies that are brought out from the apiaries and the project, a kind of crop. What we measure will thus be the production of new colonies and survival of colonies to the next season, the difference of fitness. If colonies survive to the next season is not only dependent on the varroa and virus levels in the colonies, but also on other circumstances that influence the survival and how a colony thrive, for example other pathogens like nosema and quality of food like pollen throughout the season.

Start and number of years

Instead of starting the project with 5+5 colonies with each type of bees, we have choosen to start from a fewer number of hives and increase the numbers. And we plan to continue the project for at least 3-4 years. We have choosen areas for the test that are low in nectar and pollen sources. That’s also a reason why the number of hives are restricted to five in each part, which makes a total maximum for each type of bees 5+5 colonies, 5 small cell and 5 large cell.

 

CARNICA

Four Carniolan colonies, all of them being sister queens from a pure bred Carnica/Carniolan stock, were divided in two groups with 30 m between the groups. These groups were placed in a deeply forested area far enough from the Elgon bees. Here it was no farm in the neighborhood, like it is where the Elgon bees are placed. One group was established on Mann Lake’s standard plastic frame, 4.95 mm cell size. The other on Anel plastic frames with 5.5 mm cell size. Frame size medium (448 x 159 m). Hive type well insulated styren plastic boxes.

The Carnica bees 2014-2015

The Carniolan queens we received in 2013 were introduced into Elgon small cell (SC) colonies on 4.9 mm cell size shallow sized frames (448 x 137 mm). The Elgons are adapted to SC during many years and if nurse bees fed and born in SC should be of importance that criterium should then be met for this test. The Carniolans in their homeland could not draw and thus live well on ”SC”. Here they were adapted immediately through this process, but they could not draw wax foundation 4.9 well even though they lived well on 4.9. Probably because they were not genetically adapted to small cells. Mann Lakes 4.9 they could draw well. Probably because of the high plastic cell wall starters which they couldn’t remodel

In 2014 half of the Carniolans got only Mann Lake’s 4.9 (SC), half got Anels 5.5 (large cell, LC). During 2014 they were this way transferred to these two types of frames. Increasing cell size in the LC-group up to 5.5 was no problem either as they were adapted to 5.5 in their genetics before they came here.

All the Carnica/Carniolan colonies were treated with thymol in 2013, but not much, and in September 2014 after they were moved to their test destination. No DWV-bees were observed in 2014.

The LC part of the Carnica bees 2015

In 2015 in June the LC-group (both colonies) showed 6% varroa level and crippled winged bees, one colony quite badly. They both got one treatment with two homemade thymol pads with about 5 gr thymol each. The LC-bees gave no crop. The Varroa level had not increased again very much and was only about 1 %.

The SC part of the Carnica bees 2015

The SC colonies had 0.3% and 1% varroa level respectively. In beginning of June a so called walk away split was made from one of the SC-colonies. The new queen then of course mated to very closely related drones.

The strongest SC-colony gave a small crop.

In September the SC-colonies still had only around 1% Varroa level. None of the colonies got any treatment in the autumn due to the low varroa levels. The SC-colonies thus got no treatment at all in 2015.

The Carnica bees 2016

The LC part of the Carnica bees 2016

The weakest of thee LC colonies didn’t make it through winter. The second one looked fine in May.

The weather was then rainy and chilly for several weeks, and when the beekeeper returned in late May to monitor varroa levels, in the remaining LC-colony he only found some dead brood and a few dead bees on the bottom.

The SC part of the Carnica bees 2016

In spring 2016 the now three SC-colonies were doing fine, two of them though small in size.

In the three SC-colonies the varroa levels were 3-4% in late May and some crippled winged bees appeared. Thymol pads were applied in June. A walk away split was made from the strongest SC-colony. The weather was unfavorable and the other three robbed the split. It thus died.

In September the three SC-colonies looked fine and got no treatment. The bees superceded the three year old queen.

The Carnica bees 2016-2017

The three SC-colonies were moved to an apiary with better resources for nectar and pollen. Some more pure bred Carnica queens were received in 2016. They will be used to biuld up the test apiaries again. Daughters will be bred from these and mated in the apiary with drones from the survivor colonies of the SC bees.

The whole season of 2016 was bad in producing nectar and pollen. The colonies had a hard time growing in size. It was late in the season when complementary feeding in preparation for winter was done that they grew somewhat in strength. That was the reason these bees were moved to a better place for food.

All three colonies actually were weaker than wanted going into winter. Two colonies made it through winter. The third and weakest died. This colony had probably survived if it had been fed honey (or fondant) and pollen during the worst nectar- and pollen drought periods.

 

ELGON

Six Elgon colonies of two different mother lines divided in two groups with 3 colonies each were set up. These groups were placed in a deeply forested area with a small farm in the neighbourhood. The two groups were placed about 700 meters from each other. One group got Mann Lake’s standard plastic frame with small cells (SC), 4.95 mm cell size. The other got Anel plastic frames with Large cells (LC), 5.5 mm.

Two sister groups were used. One sister group consisted of 4 queens, 2 SC and 2 LC. The other sister group had two queens, 1 SC and 1 LC. Frame size is medium, (448 x 159 mm). Hive type with well insulated styren plastic boxes.

The Elgon bees 2014-2015

The Elgon groups were established with new queens in 2014 and transfered successfully to Mann Lake’s 4.9 and with big difficulties to Anels 5.5.

The queens in the LC colonies were very hesitant to lay in their large cells. One queen totally refused.The broodnest of that queen consisted of only two shallow SC-frames. The resulting colony was of course small going into winter in 2014, but it wintered together with the other two LC colonies in their test apiary.

Most of the colonies, SC and LC, were treated in 2014 with thymol but mostly only in May. So this Elgon test groups of 3+3 were not managed in regard to the Varroa mites, similar to the Carnica groups. In the Carnica colonies the varroa populations were evened out between them, by treating them with home made thymol pads in September 2014.

The Elgon test colonies were taken from different apiaries and the varroa level in the colonies were not known when they were brought to the test site in late August. Earlier in 2014 the colonies who had wingless bees were treated with thymol, in May that was.

The LC part of the Elgon bees 2014-2015

In spring 2015 the Elgon LC group continued to create problems as the bees protested against using LC combs for brood by supersedure their queens, probably in an adaption process.

In April before grafting time and any drones were flying one LC-colony was queenless. The new virgin queen had of course failed to mate and was gone. I combined the queenless colony with the mini colony (the one with the queen that had refused to lay but in the two shallows). This queen still refused to lay in any other comb than the two shallows, so I tried to fool them by giving them a couple of 5.3 mm cell sized plastic frames on each side of the SC combs. That worked. When the 5.3 were filled on each side of the 4.9 they started on the 5.5 next to the 5.3.

It seems it is the workers that prepare the cells for laying, not the queens that are deciding in which cells to lay. (This experience is also in line with what is written in old books from beginning of 1900, that when broodnest have 5.1 you could use 5.6 in honey supers without excluder as the queen didn’t lay in the 5.6.)

In late April 2015 the third (now the second as the other two were combined) LC-colony had a virgin. They were also trying to supersedure their queen. No drones available yet. So she failed. The colony got a queen cell in second half of May. That queen got laying. This colony had 5% varroa level in August and got thymol.

The first colony (former first and second combined) got a small piece of thymol (actually both parts that were combined got half a piece each) early in spring to help against eventual patoghen problems as they had different kind of problems (weak but queenright and queenless). This colony showed only 0.3% Varroa level in August and got no treatment.

The SC part of the Elgon bees 2014-2015

In 2015 the three Elgon SC colonies developed well. Splits were made from two of them. One failed, but finally got a laying queen very late in season. It ended up weak. It was lost during coming winter, the only loss of the Elgons. The smallest of the overwintered colonies had a queen that was laying badly. It was killed and replaced by a ripe queencell.

Four of the now five colonies showed crippled winged bees in July and had Varroa levels between 2-7%. Even the 2% colony showed a few DWV-bees telling me the virus levels in the colonies were quite high. One 3% had no DWV, the weak one mentioned above and it was the only one that didn’t get treatment.

Because the varroa populations in the colonies weren’t allowed to grow strongly (still there were enough viruses in 2015 after years of somewhat higher varroa and virus pressure in the Elgon apiaries of Erik Österlund), the virus amounts in the colonies decreased and also there was no silent robbery. And the varroa populations were evened out at a low level. Thus the situation now was much more comparable with the varroalevels in the Carnica colonies in autumn 2014

The Elgon bees had better nectar flows than the Carnica in 2015 and the Elgon colonies gave a good crop from the Heather in 2015. The average crop was about the same for both SC and LC colonies. In August none of the SC Elgons had above 3% varroa level. They had 0%-3%, and got no more thymol. No colony swarmed in any of the test apiaries.

The Elgon bees 2016

In spring 2016 one of the Elgons, the very weak one in the SC-group died (as mentioned above). Both LC colonies survived.

The LC part of the Elgon bees 2016

In the LC-group splits were made from both colonies. Weather was bad and one failed to produce a laying queen. It got a new ripe queen cell. The parts with the ”old” queens (from the year before) both superseded their queens, in line with experiences in 2015. This year they waited until beginning of summer when there were drones around. Maybe the bees had adapted somewhat to LC now.

The season of 2016 was very bad so no crop was secured from the LC-group. In spring the varroa levels were 0.3% in all four colonies (they became four after splitting in late May). In early September it was 0% – 8.6% – 0.9% – 4%. The two with highest levels were treated with thymol. The other two not. We can see that two colonies had very low levels of Varroa mites. This indicates a good genetic set up for Varroa resistance, also to be able to work with large cells apparently. The queens in the colonies with low Varroa level are sisters, mated in the test apiary. They are daughters to one of the colonies in the apiary, one in a split. The other as a result of supersedure in the mother colony producing this split.

The SC part of the Elgon bees 2016

The four remaining colonies in the SC-group gave a split each. Season was bad and two of the splits failed. A small crop was secured from the strongest of the colonies.

The two colonies with two year old queens supersedured these later in season. The 6 colonies all had 0.3% varroa levels in spring. In August the varroa levels were between 0-1.7%. As we had decided not to keep more than five colonies in each of the four parts of the test, colony no 6 of the SC-ones (the one with 1.7%) was removed from the test area. It wastreated with a small amount of formic acid to get an idea of the mite load and also test the shaker method. It fell 10 mites in a couple of days. The other 5 colonies remaining at the test site didn’t get any treatment.

The Elgon bees in the beginning of 2017

All four colonies in the LC group wintered well, in spite of that two of them were almost too weak, those that had had the highest Varroa levels and been treated.

One of the five SC colonies defecated a lot on the outside of the hive, though not much inside. They did not have a large amount of honey left for winter the previous autumn. And it was of good wintering quality. The winter before all colonies had had a large amount of difficult winter honey, from heather. The colony that died was the strongest and smallest Varroa level. It measured 0% on 400 bees. The was a good amount of food left in the hive after it had died. The colony had an old queen, and just a few meters there had been quite some traffic during late winter from a tree harvester. The other colonies looked fine, with almost no defecation.

Harvest and Varroa level 2015 and 2016 in SC and LC parts of the Carnica bees. The sites for Carnica and Elgon bees are not comparable as the Carnica site was didn’t have the same amount of food sources. Click on the picture to get it bigger and of better quality.

 

Harvest and Varroa level 2015 and 2016 in the SC and LC parts of the Elgon bees.

RESULTS

Losses

The losses in the Elgon groups have been quite normal, on the lower side. It has in percentage been higher in the Carnica groups, especially among the LC bees. The higher amount of losses can be explained by the low availability of pollen and nectar, especially during 2016. That’s why the test site for the Carnica bees has been moved. One conclusion is that during times with small amounts of available pollen and nectar a solution could be to feed the colonies fondant/honey and pollen to develop healthier and stronger colonies better adapted to survive winter.

The strategy of 3 %

The strategy to measure the Varroa level a couple of times during the season and use Varroa treatment (dish cloth pads, about 50 x 58 x 1.5 mm [2”x2”x1/16”], drenched in thymol) when/if the Varroa level is higher than 3 % (only treatmnent in these colonies, not in those below 3 %) has minimized reinfestation, maybe altogether. You thus get a true picture of the Varroa level in the colonies and thus a better selection of the most resistant colonies and the most susceptible ones. You could for example have expected that the different cell size groups had affected each other so that eventual difference in the varroa levels had evened out, especially among the Carnica bees as the two groups there were only 30 m apart.

Little need for Varroa treatment

Relatively little of Varroa treatment has been used, probably partly explained by the absence of reinfestation, no silent robbing. Most treatment has been used in the LC colonies of both the Elgon (2016 when reinfestation had been removed) and Carnica (2015, in 2016 there was no LC left) colonies.

The strategy of 3 % seems to have eliminated the need of Varroa treatment in the SC part of the Elgon bees due to elimination of reinfestation and enough good development of the varroa resistance with the Elgon bees.

This strategy has also lessened the need for varroa treatment to every second year with the SC part of the Carnica colonies and the need for treatment then has been small. Thymol in this context has been effective.

Cell size and fitness

In the LC part of the Carnica bees the need for treatment has been bigger probably because of a quicker development of the Varroa population. It seems fitness has been lower here probably partly due to the bad pollen and nectar availability. But fitness may also be lower because of other reasons. The Carnica LC colony that died in May did not die due to high varroa level. Lack of protein and/or other pathogens (like nosema) can be the cause. The Carnica test site is moved to a place with better food sources.

One can object to this conclusion of lower fitness for LC bees because the number of colonies are low.

On the other hand were all original queens in the Carnica group sisters and all colonies in SC and LC groups (Elgon and Carnica) are behaving consistent in this respect. And any difference in fitness between the two cell size groups among the Carnica bees should have been to the advantage of the LC colonies because the SC colonies had become inbred. Usually follows a lower immune system with inbreeding. Possible impact of this small distance would have been small(-er) difference in the varroa levels between the two groups due to evening out of the varroa populations. The 3% strategy, measuring varroa levels and treatment when it was above 3%, lowered the varroa populations enough to eliminate (totally or enough) the silent robbery.

In 2016 the only colonies that needed treatment were in the LC colonies of the Elgon bees. It should though be noted that with a stock of bees that have been selected for Varroa resistance it is possible to find colonies that are resistant also on large cells. Two colonies (with sisters queens) had very low levels of Varroa mites.

The honey crops, the bee strength of the colonies indicates, and the resulting number of colonies in the SC and LC parts of the stocks of bees indicates that it is no disadvantage to use small cells in the broodnest, rather the contrary.

 Summary of production of new bee colonies, increase in the number of wintered bee colonies. These figures could be seen as a measure of the vitality of the different cell size groups. There is a difference to the benefit of SC bees both in the E group (Elgon bees) and the C group (Carnica bees). Click on the pictures to get them bigger and of better quality.

 

Suggestion on a breeding program for increasing Varroa resistance in a bee population. The background for these suggestion is the results of this project, so far.

 

1500 Varroa Treatment Free

  South Dakota is Buffalo and Indian land in the northern part of the Midwest.

I talked to Chris Baldwin some time ago. He is a commercial beekeeper running about 1500 bee colonies. In summer his bees are closer to his home in South Dakota. In February they pollinate Almonds in California. After that they are going to east Texas for queen breeding and splitting. Focus in handling the mites is not eliminating the mites, says Chris. It’s eliminating susceptible bees.

 Beginning of November the bees go to Texas for winter. February 1 to California for Almond pollination. March to Texas for splitting and supering. May to South Dakota for honey. (Basic map illusttration: http-//d-maps.com_carte.php?num_car=5184&lang=en)

Chris hasn’t been treating his bees against mites for more than ten years. Last Coumaphos 2003, Only Oxalic 2004 and 2005. Nothing in 2006 and finally Thymol in 2007. After that nothing. He’s loosing bees yes, but not because of mites really. He’s keeping bees like bees were kept before the arrival of the Varroa mite. When he talked to another commercial beekeeper recently, his comment about Chris’ bees was that they probably could handle all farmers chemicals better as they didn’t had to deal with miticides as well in their hives.

Blacklisted

When he shares his experiences with others he is many times surprised of the response, or lack of response. Maybe some think he’s earning money on selling queens from his “pretended varroa resistant bee stock”. Maybe because almost all(?) scientists say you must treat against mites to get your bees to survive. But Chris don’t do that. He lives on his bees producing honey and pollinating crops.

There are so many examples now of treatment free operations for many years that we can write down a working plan to produce resistant stocks. It’s not telling the whole truth leaving out the growing number of treatment free beekeepers and their working plans for their success.

When he talks to scientists, many well known, about his bees, they look kind of strange in silence for a while and then walk away. They don’t show up at his yards wanting to investigate his bees and methods to find out more, as you would expect.

Chris has good references, the bee inspectors in his areas in South Dakota and Texas.

Once he had a columnist from a bee journal showing up asking and looking at his operation. I’m sure the readers would have loved to know more about how Chris is managing his bees. But he’s doing many things the opposite way to what many times is preached from the front.

No wonder he said to me he feels like he’s blacklisted. By whom and why, if that’s the case?

A bigger picture

After some additional communication with Chris about his operation the picture gets more clear and gives more food for thought. It’s really interesting and valuable to put his experiences and management system beside others’ to get a better understanding of our fascinating honey bee and what it means to us as an economic resource and understanding its role in nature.

California in February

Chris may well be the only big commercial beekeeper focused on pollination services that is treatment free when it comes too the Varroa mite. His bees are exposed to agricultural chemicals, drifting of other beekeepers’ bees into his colonies (which may well bring mites and pathogens of different kinds) and his bees visiting weakened hives to rob from (and pick up mites and pathogens).

It’s not difficult to understand that his bees might well have problems due to this. Pathogens like nosema, plus chemical residues from spraying of the almonds for example and extra mites and viruses picked up will make life hard for the bees when they go back east Texas in March after almond pollination in California.

  After pollination in California the bees go to Texas, here ready for supering.

Texas in March

The colonies return to Texas in late March. There they are supered for growth and maybe honey production. April flows in Texas are unpredictable.

Not all colonies went to California from Texas February 1 for pollination of the almonds. The remainder are scattered to out yards for buildup and also prepared for cellbuilding, which begins in early March in Texas. Nucs are made in March and April.

Africanization is not a problem in east Texas and his number of hives is big. So his drones dominate the air well. Also there are few fives from other beekeepers in his area.

 Preparing cellbuilders in early March with colonies that stayed in Texas when the main part went to California.

Securing cellbuilding

In a commercial operation every part in the system have to work good enough to make the system work and bring food on the table. One part that is maybe more critical than others is cellbuilding in the queen breeding part.

European Foulbrood has grown to a persistent problem in America. It may well bee due to increasing amounts of chemical residues in for example wax combs putting higher pressure on the immune system of the bees.

Chris will not have the chemical residues from miticides, which may well help his bees keep a better standard on their immune system than bees in other commercial outfits. Still he can during springtime at just the time of cellbuilding experience some problems from European Foulbrood. To be sure he will be able to produce the number of queen cells he needs, he gives the colonies involved some tetracycline in spring. That takes care of this problem efficiently. This is the only drug he uses.

 Colonies prepared for going from Texas to South Dakota for honey production during summer.

Summer in South Dakota

Colonies that have collected enough of honey for a food reserve are shipped to South Dakota for the clover flow, starting early May. Or they may stay in Texas longer for the Chinese Tallow tree bloom. It is often a difficult decision which will give the best flow.

 After harvest in October iSouth Dakota. Honey supers are removed.

Winter in Texas

Harvesting of honey may begin in July and go through October in South Dakota. The bees are fed if necessary, then shipped to Texas early November, hopefully before the first blizzard in South Dakota.

 544 colonies loaded for transport from South Dakota to Texas in November. Another 544 colonies are waiting to be loaded.

Annual losses

During summer about 20% of the colonies are lost due to queen problems. At least partly these queen problems may come from the rough circumstances in the pollination services environment. Pathogens and chemicals picked up there. In January the die offs are taken care off, as well as the bees alive. If necessary colonies are fed. Winterlosses and losses experienced after the almonds in California can together be 10-20%.

This makes a total annual loss of about 40%, which these days is the average in America, wheather you treat against mites or not. Quite some years ago now Chris had a “CCD-year” with 70% losses. But weather was favorable and he could recover colony numbers from remaining colonies in one season.

40% losses is a little too high, but up to 30% are okey for Chris in his management system. Actually some amount of losses are more or less needed to weed out the worst colonies and multiply the best to improve the stock continuously and keep the numbers stable. Also to minimize the swarming through making nucs. He is not into selling colonies or queens. He gets his income from pollination services and honey production.

Hive configuration

Beekeepers love to discuss different details in their management system. One is the hive configuration. And you can have quite animated discussions going on concerning how good or bad this or that part is, for example 8 or 10 frame boxes and medium or Langstroth boxes. What you many times forget is that each part of a management system, including the hive configurtaion’s different parts, is a result of this whole management system in which each part fits well enough for the beekeeper. If you change one part, you may have to change also other parts to make the system work well for you. And special circumstances for you may play a role why you have chosen the solutions you use.

Chris Baldwin uses a 10-frame system with a shallow box (5 & 11/16”; frame 448 x 137 mm) on the bottom. It is always there. It’s kind of an expansion space which the bees use as they want, more or less without control from the beekeeper. The bees remodel, tear down and build back, the combs in the frames there. Sometimes they are bad in shape, sometimes a lot of drone comb, sometimes good looking well used by the bees.

The next box is a Langstroth deep with 9 combs (frame 448 x 232 mm) and a plastic division feeder. It’s tight, but that keeps out burr comb. When moving combs the feeder is first taken out to make space for easier handling. This is the broodnest all the time. Then comes the queen excluder. The supers are normally 8 combs in 10 frame deep boxes and medium boxes (the latter frame 448 x 159 mm) with metal spacers. Almost no plastic combs are used, but wired wax foundation in wooden frames, since many years.

The bees

Colonies can grow very big on this set up. His bees uses the combs for brood efficiently. They are much more conservative, frugal with food reserves, than common Italians in America. He has always liked the darker kind of bees, Caucasian and Carniolan types. Today he has all colors. He started selecting among his bees creating his own stock many years ago. When the Russians came on the scene he started buying breeder queens of those and they changed the game concerning Varroa resistance. He refers to his friend Kirk Webster having the same experience using Russians.

Old combs

He uses no system for wax renewal. Well, he does in a way. After the queen breeding and nuc season is over, when a colony dwindle, for example looses its queen or having a failing queen, he doesn’t have any queen cells to save such colonies.

Broodnest boxes, deeps and shallows from these failing colonies go on top on other colonies as honey supers. After harvesting these boxes are extracted separately. The uncapper has adjustable cutting depths. When extracting brood combs he sets the uncapper on the deepest cut settings. It really cleans up the oldest nastiest comb.

Many of his brood nest boxes stay out in the field for years, but a certain number do get extracted and thus cleaned up quite a bit. He only cull combs that look horrible or have broken frames. Most of his combs are more than forty years old.

Nucs

He in first place uses the extracted brood combs when making nucs. He starts the nucs with three good deep brood frames and fills up the box with extracted deep combs and maybe a food comb. This box is put on a shallow extracted box. The nuc gets a ripe queen cell and maybe a good feed.

Broodnest

This hive setup, which has a smaller brood nest than many others use (many use two deeps), works fine in his management system. As annual losses are somewhat high (which is the “normal” average in America) many nucs are made. Still the colonies have time to grow to be strong enough for both pollination and honey production. And this is done just perfect with this 1 and ½ box broodnest setup. When he moves hives, he can take a bigger number, 4 stories with 4 hives on a pallet, 544 on a truckload.

Cellsize

Chris doesn’t really care about cellsize. If he did he maybe would have to change management system when it comes to wax renewal. He hasn’t found any reason for using more labor in this part of his beekeeping.

So what is the cellsize in his combs? Today when he buys wooden frames with plasic foundation (these are cheapest and quickest to get at work into the system), most common is 5.4 mm, to begin with. Forty years ago who knows, maybe 5.2 mm was what was bought, (sizes 5.1-5.6 was available). But during the years cell volume has shrinked of course due cocoon residues. When old combs have been cut down, the cell bottoms have been left untouched. The parts of the combs closest to the midribs are “smaller cell” still, by the added cocoon residues. But the compactness of a real small cell comb is not there (more cells per area unit).

Living life

Beekeeping makes you nature focused and Chris often observes wildlife while working the bees. Deer, antelope, hawks, eagles, owls, praire dogs, coyotes, pheasants, grouse, badgers and so on. He once saw six bull elk out on the praire. At another time a golden eagle carried off a coyote. The land in South Dakota isn’t as flat as it appears many times, but it’s so treeless that you often can see horizon to horizon.

What about next season then? Weather comes up differing with cold and heat, drought and rain. And we need rain too besides sun. Next season will always be better!

Chris Baldwin is doing his share in putting food on the table in US through his bees’ pollination services, and yes, somewhat also on many other tables around the world that import almonds.

Reworked website with new info

Hello dear beekeepers!

I’ve been reworking my old website. not my blogs. The English part became ready enough to be published and I launched it on http://elgon.es

elgon-website

There are quite some new material there. In the article “Resistance breeding” some of the experiences from 2016, very positive and quite important experiences. On that topic there will be more info later on.

This website is so called responsive, which most are these days. It means that it automatically adapt to different screen sizes, down to that of a cell phone. It’s made with and easy working and free app called Rocket Cake.

Bees grooming, shaking and biting mite

Already in 2002 Sven-Olof Ohlsson in Munsala Finland filmed bees grooming, shaking and biting mites. I have published two of his video clips on YouTube for him. You can see one here where the the mite had attached fast between thorax and the abdomen. The poor bee seemed to never stop shaking to get the other bees to help her. Ohlsson stopped filming after 20 minutes, but the bee didn’t.

Here you see a successful bee removing and biting the mite. Another bee gave it a bite as well. It moved too much.

Lasting learning?

In one of the recent blogposts I wrote about non-resistant bee colonies against varoa mite, learning from resistant worker bees how to deal with the mites and being resistant. It seems now that these colonies that has learned resistance have to have worker bees from genetically resistant colonies drifting into them continuously to stay resistant.

This resistance went on for at least a couple of years. I referred to experiences of Hans-Otto Johnsen and Terje Reinertsen (http://www.elgon.es/diary/?p=880)in Norway and Magnus Kranshammar (http://www.elgon.es/diary/?p=890)in Sweden.

A.) In the Norwegian cases colonies with queens from non-resistant stock originally were kept in apiaries together with resistant bee colonies. Bees are kept on small cells.

B.) In Magnus’ case it was somewhat similar as the colony of the original queen, which was the result of genetically selected resistance, and splits from it with queens of originally non-resistant stock, were kept in the same apiary. The total number of colonies was not big here. These bees were kept on large cells.

A.) A couple of years ago Hans-Otto started a variety of the first tests he made mentioned in the blogpost above. He introduced virgin queens of non-resistant stock into splits from his Elgon-stock. In this test he didn’t place these new colonies in apiaries together with his resistant stock. Instead he placed them in an apiary of their own in the forest, a lot more than 2 miles (3 km) from other bees. For two years these colonies functioned without problems concerning Varroa.

This autumn they all showed crippled winged bees. He made a test with the Bee Shaker (http://www.elgon.es/diary/?p=794). About 35 mites from 300 bees. 11-12% Varroa level. Probably there was resistance in the colonies at least the first year as long as the old worker bees were alive.

In an apiary all colonies will share more or less worker bees with each other. The whole apiary works more or less together. This depends of course also on how much worker bees from different colonies drift. In an apiary with resistant colonies, bees from resistant colonies will help keeping non-resistant colonies resistant. (And if the non-resistant colonies are many compared to for example a single resistant, this may create problems for the resistant one.)

B.) Two splits from a colony with a queen of non-resistant stock, which anyway were resistant, were moved to an apiary of their own in a forest about 2 miles (3 km) from other bees.

The mother colony of the splits was kept in the same apiary as the colony with a resistant queen (which was still alive this year). It was this resistant queen’s colony that gave bees to this mother colony of the described splits. So you could expect some drifting had occurred with resistant worker bees now living in the colony with the non-resistant queen. Thus some good resistant worker bees were living in the splits as well to begin with, until they died their natural death.

Drones from the non-resistant queen of the mother colony of the splits were of course present in these. But of course there were also drones in some colonies 2 miles (3 km) away. Those colonies were of Elgon heritage, but not of the very best variety of resistant stock. The splits got virgin queens from an Elgon colony of good resistant quality. The Varroa level was initially very low in the splits, about 0.3% (without treatment this year or the previous year).

The splits developed very well after the queens were mated and laying. In the beginning of September the Varroa level was 2% and 3.3% respectively. It had increased more than expected, but was not alarmingly high. The cell size in those splits was initially 5.4 mm, that is large cell size. (Resistant thus in spite of the large cells.) The story of those bees are told here: http://www.elgon.es/diary/?p=890. But the virgins came from established small cell size colonies since many years. The plastic combs used for increase were small cell. The 3.3% part had relatively somewhat more left of large cell combs.

131mk1 One of the splits in case B. The original large cell combs are of an old Swedish (as well as an American) size, 12”x12” (30 x 30 cm). With the help of adapters these combs are placed in boxes which hold Jumbo sized frames (448 x 286 mm) plus a deeper bottom board. The combs used for increase are small cell plastic Langstroth from Mann Lake (http://www.mannlakeltd.com/beekeeping-supplies/category/page19.html).

C.) In a project that has been going for a couple of years now, one apiary was placed a lot more than 2 miles (3 km) from other bees. The queens were of non-Elgon, non-resistant, large cell bees. They were introduced into Elgon colonies on small cells in 2013. In autumn 2014 they were moved to their test apiary and treated with a small amount of Thymol to ensure an in the test initially small and quite even population of Varroa mites. They had during 2014 been standing in apiaries with Elgon colonies. Thus probably containing some drifted Elgon worker bees. The test apiary was poor from a nectar point of view. In 2015 the Varroa level in autumn was low, around 1%. A split was made during 2015 and queens shifted to daughters made in the split in two of the units. The virgins were mated in this apiary. One of the originally queens, all had been sisters initially, were still left in its colony. The new queens were of course very inbred as the available drones were very closely related to the virgins.

In the middle of the summer 2016 the Varroa level was 3-4%. A couple of weeks later all three colonies showed crippled winged bees. They were treated with two pads with 5gr Thymol each (once) after which they recovered.

Conclusions

The experiences given here makes it probable that there are more than one component necessary for a queen of a non-resistant stock to have a resistant colony. First the colony with a non-resistant queen must become resistant. It can become resistant quickly in two ways. (One may ask whether it is desirable to deliberately do this.)

1.) Worker bees from a resistant colony can be united with a non-resistant colony through shifting the places of a resistant and a non-resistant colony. Most of the other colones in the apiary are resistant. It is uncertain how many of the colonies that should be genetically resistant.

2.) Splitting a resistant colony and giving the split(s) virgin or laying queens of non-resistant stock.

To maintain this resistance achieved, still with a queen of non-resistant stock in the colony, when the first resistant worker bees that came along with the splits are worn out and dead, new resistant worker bees have to come into the colony in some way. (Resistant worker bees are bees in colonies that show resistant behavior to such an extent that their colony can rid themselves of mites through different kind of hygienic traits.) It seems the number of resistant worker bees needed to come from other colonyies “per time unit”, are not very many. By just keeping the colony in an apiary with resistant colonies this seems to be achieved, probably through drifting of worker bees between the colonies in the apiary.

In all cases above, A, B and C there were no new resistant worker bees drifting into the colonies. In case B though virgin queens from a resistant queen were introduced, but no new bees from the original resistant stock were re-introduced. Instead new workers with probably better genetic set-up for resistance were born. But there were now probably no, or very few, resistant worker bees left that could teach newborn bees. At least this is a conclusion that is close at hand, to explain the increase of the Varroa level. It will be interesting to see what will happen further on in these two colonies. Hopefully the virgins were mated to other drones than those that came along in the splits from the genetically non-resistant queen.

No shortcut

It is thus no shortcut to get resistant bees, to split genetically resistant colonies and introduce whatever kind of queens into those splits (of non-resistant heritage)! What these experiences tell us is how important it is to increase your number of colonies and replacing the dead outs by splitting the best resistant colonies. The very best might many times be to let those splits raise their own queens. And in addition to this breed queens from good resistant colonies of good heritage in being resistant.

Factors for reinvasion

Robbing

Several years ago, it was common that there were always noticeable, even many bees flying around the ventilation and the door to the extraction room. It has become less and less bees every year. This year there have been virtually none. However wasps have been in abundance. Even though I often walked through the door in July and extracted some of the honey then. And it was no honey flow then.
Last year’s breeding queen no 1 gave many new queens working the colonies this year. That has apparently had a big effect this year. Last year, I used a lot of thymol as wingless bees appeared in many colonies. This year I barely needed to use any thymol at all. I find it hard to draw any other conclusion than that my bees have become more resistant to varroa.
However, there are a few colonies in some apiaries which are close to other Beekeepers bees where the mite level suddenly increased quite some in late July/August onwards for a few weeks. It seems to indicate so-called silent robbery from my colonies from hives that are affected by larger amounts of mites so that they do not maintain a good entrance defense.
Then when I was told about the problems some beekeepers had in Finland with imported Italian bees when it comes to how quick they were to rob and as often as these colonies must be treated against Varroa, I made a connection here.
Bees that are not inclined to rob have less problems with reinvasion of mites. Bees that have less problems with reinvasion can be called more resistant to Varroa.

Drifting

Another factor that is important for reinvasion is the tendency to return to wrong hive, to drift. I have sold a few queens to countries further south in Europe. I got some feedback recently from a beekeeper in Germany who this year introduced two Elgon queens with differing color, one light and one dark. (One of the features I do not attach great importance to is the color and therefore it can vary a lot.)
Her carniolan bees drift a lot, she has noted. Now she split a hive in two and put the two parts very close together with the entrances adjacent. She noticed that Elgon colony with striped bees contains only striped bees. The hive with without beige striped bees, had only dark bees, no bees with beige stripes. None of these colonies’ bees thus drifted to the neighbor.
It seems that part of the Elgon bees’ better resistance can be explained that they are less inclined to rob and that they drift less.

Reinvasion is worst

Last year 2015 was a bad year for the bees in more than one respect. Long cold spring and bad summer. But late summer was good as was the autumn. The bees could recover and prepare for next year.

Fresh pollen was low in spring 2015 . The immune system wasn’t at its best. And the bees couldn’t fly as much as they needed. Where nosema was present it could infect new bees instead of disappear with sick bees as those couldn’t make it back to the hive.

I treated more hives and used more Thymol last year than I had done earlier years. Early in the season I saw what was coming and decided to try some new strategies to get forward on the path to better Varroa resistance and finally get rid of chemicals.

Leif Hjalmarsson

Very often I have reminded myself of the experiences from an apiary of Leif Hjalmarsson in the southern part of Sweden. He got 5 Elgon queens from me already in 1997 and established an apiary at least 2 miles from other bees. The bees to which he introduced the queens had been treated with Apistan for about 5 years and were very low in number of mites. The bees had probably been adapted somewhat to the presence of the mite. Leif used large cell size, 5.4 mm. He never had to use any miticide on those bees until he died early this year. I do miss him! He was dear friend and a good beekeeper.

Already when we started to combine the Monticola bee with our Swedish bees there could be seen resistance traits. Therefore I had hoped that Varroa mites would be no problems when they arrived in my apiaries. This would not be the case. Even though I had as well regressed my bees to small cell size, 4.9 mm.

I have been wondering since 2008 when the mite started to create problems, why they were a problem for my bees with me, but not for “my” bees with Leif? Last year I decided I had to let the fact that Leif Hjalmarsson established this apiary of his more than 2 miles from other bees affect how I designed my bee management. I want of course to get better resistance with my bees in my apiaries.

A lot of focus had to be put on avoiding reinvasion, bees picking up mites from colonies with high infestation level of mites, within my own apiaries and others within about 1.5 miles.

Better selection 2015

But the difficult circumstances for the bees last year also meant that selection pressure was stronger and it was easier to choose a good breeder, if there was any. And there were good breeders, especially colony S241 which I have mentioned in an earlier blog post, but also C243. I introduced many new queens in my colonies last year, especially from S241. I had only found one mite in S241 in the brood when I tried to found out the VSH degree. And that mite had no offspring.

1. Project 1, 3 miles from other bees in a forested area started in autumn 2014. I had not treated the colonies in this project in that autumn when the project apiary was established. During 2015 I treated a couple of colonies when they showed crippled winged bees. The varroa level was not alarmingly high, so virus effects came early in infestation. Evidently reinvasion from the colonies with DWV didn’t occur very much to the other colonies in the project apiary, as in autumn 2015 varroa level was low in all colonies. Varroa level was also very low this spring 2016, and so it is now late in summer 2016.

Bee shaker1 The Bee Shaker is a valuable tool in getting a quick and easy figure of the Varroa level in the bee colonies in an apiary. Type in the search box: Bee Shaker – at the top of this blog, and you will find more info about it.

2. Project 2 started late summer 2015 as I treated all colonies in an apiary 1.5 miles from other bees of mine with an effective pesticide/miticide in August that year (I hated to do use it), to mimic somewhat how the apiary of Hjalmarsson was established. The varroa level now in August 2016 was surprisingly low, almost not detectable. It was in this apiary I had planned to reduce Varroa level by removing all capped brood frames twice with a week in between, in those colonies showing higher Varroa level than 3%. The highest level now in August was 0.3%.

Bee shaker2 The Bee Shaker will help you to decide if any colonies has to be removed (or any other action taken) from your apiary in which you are developing the Varroa resistance in your bees. It’s a simple and quick method, but you kill 300 bees. That is though nothing compared to numerous bees dying if you do nothing. Viruses and mites killing thousands of bees besides the normal die offs from worn out bees in their daily work, where tens of thousands of bees are dying.

3. Those colonies I decided last year I would shift queens in this year, I treated with thymol in April/May this spring even if they showed no signs of Varroa or virus symptoms. With this I think I secured that those colonies wouldn’t produce mites that could reinvade the other colonies in the apiary. These kind of apiaries are the most numerous of mine. I have not checked the varroa level in all colonies spring and late summer in these apiaries.

Up til now in late August 2016 I have found this odd colony in just a few apiaries, showing one wingless bee. I have tested those colonies with the bee shaker for the Varroa level and only found a few colonies with a Varroa level higher than 3 %.

In one apiary I had this colony with a decreasing varroa level during the season. Three weeks after the early August measurement with just above 1 % Varroa level, I made a new measurement. Now it showed 5 %! Too many mites for the colony to have produced it during these three weeks. Less than a mile away there is another beekeeper, with Elgon bees, but not selected for Varroa resistance for some years. No wingless bees. The colony had probably picked up the many mites from one of his colonies. I didn’t treat, but gave it a sticky board on the bottom to check the natural downfall. And a new Varroa level check will be done in a month. Hopefully this colony will be able to reduce the Varroa level. We’ll see.

An apiary at the edge

Let’s look at one apiary at the edge of “my” Elgon area. With that I mean that drones from other beekeepers’ bees can influence the matings of virgin queens. Also the risk of reinvasion is of course higher. Last year was of course not only difficult for my bees but also for the bees of other beekeepers. In this apiary I treated two colonies quite a lot last year, and also this spring and shifted their queens. The other colonies in this apiary has not been treated this year. But they were all treated last year with Thymol. Now in August I saw a bee that looked like it had the beginning of wings being crippled in one of those colonies. So I tested the Varroa level, 4 mites in 350 bees = 1.1 % Varroa level. It got no treatment of course. Very pleasing result.

A couple of small apiaries

I have a couple of small apiaries in which I checked all colonies with the Bee shaker in spring this year, 0 or a couple of mites in 300 bees. No colonies treated this spring as I didn’t plan to shift any queens this year. I had shifted some last year. I checked these apiaries now in August.

In one of the small apiaries with two colonies and a split I found 4 mites in one of the big colonies and 32 (!) in 300 bees in the other. This was too many in the later colony for it to be able to produce them by itself. No crippled winged bees. Also a sign of that those mites were picked up from somewhere else. This colony had a history of needing Thymol every year, so I chose to treat with Thymol and am planning to finally shift the queen next year. 500 meter away is double the amount of hives of another beekeeper (with Elgon bees which were not from my selection in recent years). He had had problems with one of his colonies.

The situation in the other small apiary will be described later in a blogg post of its own.

Avoid reinvasion when bees adapt

The conclusion is that it’s very important to avoid reinvasion of mites when your bees are developing their ability to control the Varroa mites. They need mites to do that, but no or few extra mites from other colnies that makes it more difficult for them to survive.

On the other hand can the explanation for the better varroa resistance with my bees, as it seems, partly be explained by the fact that I shifted quite some queens last year to S241-daughters. Bess from their colonies will drift somewhat into other colonies, as bees from all colonies do. In this case these drifted bees may well help controlling the Varroa level and possibly also teaching the original bees of the colony to fight mites better.

Genetics is of course important when bees adapt, changes in the composition of the DNA. Selection by culling the worst and multiplying the best. But bees adapt too quickly for the genetic changes to explain in all. Epigentic changes is of uttermost importance here, changes how the existing DNA is expressed, how it’s used. It’s impossible to explain the resistance developing in S. America and S. Africa in about 5 years in any other way. As epigenetic changes occur when environmental changes act upon the chemical environment closest to the bees. The precense of the Varroa causes chemical changes in the bees, in the brood cells, etc. These epigenetical changes are inherited to next generations until new environmental changes cause other epigenetical changes. We understand that chemical help against Varroa will hinder the bees’ own control mechanisms to develop fully. There will be a balance act of avoiding all kinds of miticides as much as possible without letting the bee colonies die. Avoiding reinvasion will be very important then helping the bees developing their control mechanisms fully.

As was pointed out in a previous blog post, my bees are held on small cells, which may contribute to the very low overall mite level. The mite level in Leif Hjalmarsson’s apiary he didn’t treat for many years was at least in the beginning when we measured substantially higher. He used large cells.

I’m convinced that when the bees have learnt how to control mites effectively they can handle reinavsion of mites as well, maybe also in larger numbers. I would call that VISH (Varroa Intruder Sensitive Hygiene.:)) I suspect this can take some years. Then they probably sometimes need some reinvasion to keep their skill at a high level.

Small cell size important in breeding Varroa resistance

After reading the blogpost ”Breakthrough?” an European PhD-Scientist wrote me an email with the following comment:

After reading your post I realized that you do have small cell size, but you’re not mentioning it in the actual post. To make sure that the reader’s get the full picture, the main components of your management system, this should be explained for them.

For instance, for me it’s a fact, that the cellsize used in a selection program is a factor incorporated in the population just like springfeeding appears to create a dependency of that feed to make bees start an explosive spring behavior.

As our bees are still wild animals, you can select whatever you like (or forget to see as selection-factor) to specialize your bees. Feel very good that your selection works.

But looking at the picture I have, some more ’vitality’ comes with better Varroa control. More or less ’Race’-independent. Question for me: ’slight inbreeding effect’?”

A valuable comment which gives food for thought. Thanks!

Small cell size (SC) is so natural for me, that it’s the normal thing. I forget it sometimes. Those small quick bees flying directly into the entrance are what I expect when looking at a bee colony.

It’s interesting Eric Erickson in Tucson when he started his breeding project for Varroa resistance found that many survivors that he used in his program were on 5.1 mm cell size. This was quite smaller than the most common 5.4 mm. http://www.elgon.es/diary/?p=457

Eric_EricksonF Eric Erickson when I and Hans-Otto Johnsen visited him and Lenard Hines about ten years ago talking Varroa resistance.

Erickson is said to have been forced to retire earlier than he should have. He died earlier this year (2016) well above his 70th year. There were nice obituaries, but I couldn’t find a word about his Varroa resistance program. Strange.

Every spring since I started to take my bees down to small cell size, when I took care of the dead outs after winter I saw that many combs were poorly drawn. The bees had many times failed to follow the 4.9-pattern and drawn patches of sometimes bigger worker cells and sometimes a lot of drone cells. Also when managing struggling colonies during the season the same observation was many times made. This year very little of this was seen. But I still have some colonies that can’t follow the 4.9 pattern when drawing their own combs (but they do well on already drawn small cell combs, especially colonies with heritage from queens from other beekeepers I have found interesting to try.

At the same time I’m aware that there are beekeepers that havn’t treated against Varroa for many years that still use large cell sizes. I draw he conclusion that it is possible to keep bees on large cell size and still be treatment free. But I see very little reason for not going down in cell size. The most important reason is that the bees themselves go smaller when given the chance. It must have something to do with their fitness and survival, not actually in first place in relation to Varroa.

Concerning the earlier blog post “Breakthrough?” and that I have used very little Thymol this year. Last year at the end of July I had used Thymol on about 70% of the colonies. This year at the same time of the year I have used Thymol on 2 colonies out of about 150 (I had about 150 last year too). I find it hard to believe that the only reason would be a successful breeder queen. I think better pollen availability this year has given a better immune system. And reinvasion I think is less problematic. With the latter in mind, I can imagine that adaptation to better control the mites is developing in the bees. And the absence of chemicals, in this case thymol, do not disturb this adaptation.

Another change in management is that I don’t move bees between apiaries. When making splits they stay in the same apiary. If there’s only one colony in a yard I split that colony and build up the apiary again this way (from now on). Some minor movements of bees have been done though.

Breakthrough?

Last year I saw more wingless bees than I had expected and I used more thymol than I had expected. I realized that I could partially thank the bad weather fort thias. The bees had got too little of pollen. Their immune system was not at its peak.
It was not easy to find suitable breeder queens, ie, who showed great varroa resistance. I found a colony that had not needed varroa treatment for a few years and it had not had any wingless bees. VSH test could not be done as I found only one mite in more than 100 pupae. And this mite had no offspring. So if you would allow it to determine the VSH-level, this would be 100% VSH. However, the so-called statistical significance was non-existent because of the low number of mites (just one single one). Well, the low number of mites were decisive. S241 was last year’s most important breeder colony.
This summer, I have not seen much of mites and almost no wingless bees so far. Some odd mites in 4 colonies, of more than 140 hives. Well, those who got the most thymol last year, got Thymol in May this year and then got its Queen replaced. So that’s one explanation, about 15 colonies. A colony that was a split from one of those 15, which raised a queen of their own was the first. Due to it’s history it got Thymol as soon as I saw the wingless bee. The queen will be shifted.

A problem hive had got a daughter of S241 last year. A Beeshaker test though showed 0% varroa level. Viruses still a problem in spite of no mites? 

The other day I saw a wingless bee on the hard board in front of the entrance of a colony that had got a lot of Thymol last year. It did not get Thymol in May as it was shifting its queen in May, I found a dead virgin on the hard board and drew that conclusion. I decided to make a test with the Bee shaker due to the wingless bee. I did it yesterday, July 20, 19 mites out of minimum 300 bees , 6.3% varroa level. The hive got Thymol.

1DWV 19 mites, 6.3% Varroa level – Thymol.

Today I came to an apiary with a daughter of the 241 (introduced in 2015) which have had no need for Varroa treatment in a couple of years, neither 2014 nor 2015. This colony was now a strong colony that given a good crop. With still some time to go for eventual more honey to come.

241d No need for treatment for a couple of years (2014 and 2015) plus probably this year. Actually lower Varroa level now compared with spring ( at least not bigger).

In May, I tested interesting candidates for being breeders with the Bee shaker. This 241-daughter was among those of course. The Varroa level was 2%. I didn’t give it Thymol as this was not more than 3%. I had several colonies, including several 241-daughters, that got only a few grams of thymol in spring 2015, which showed no mites at all (zero) out of more than 300 bees. The two best with different heritage (one was a 241-daughter) I used as breeders this year.

1% 4 mites, 1,3% Varroa level now.

2% -colony I tested today July 21 regarding the Varroa level, 4 mites out of a little more than 300 bees. 1.3% infestation level. At least not higher Varroa level after 2.5 months. A strong hive that has given a good crop. The Varroa level would have been much higher if the bees could not get rid of mites themselves. This colony has thus been able to get rid of mites by themselves. What a great feeling!
Now this does probably not only depend on the queen. It was introduced to a colony that had not needed any treatment for at least a year. The worker bees might have learned the new queen’s bees some tricks how to deal with mites. It would not surprise me if there is a combination of reasons for the mite fighting ability of this colony. http://www.elgon.es/diary/?p=880 http://www.elgon.es/diary/?p=890

Wingless bees and varroa level

Before varroan came there could be seen occasional bees with undeveloped/deformed wings in spring. Maybe it was the influence of DWV, Deformed Wing Virus. But it may also have been chilled brood. During the final phase of the pupa development to finished bee the wings are formed. Cold nights and too much of brood could maybe have caused undeveloped wings.

Today, one can probably assume that when you see a wingless bee, it’s DWV responsible. Varroa mites are paving the way for many viruses into pupae and adult bees that had not previously bothered bees. Moreover, these viruses multiply in mites. So today mites spread viruses more efficiently than when the mite had just arrived in Europe. Why that is so is another interesting discussion that probably involves the use of miticides.

 

The Bee Shaker

The Bee Shaker is a great way to keep track of the level of mites in the bee colony, especially in spring and late summer, so the amount of virus can be kept reasonably low by allowing people to fight the mite if it exceeds a certain degree of infestation. (If that is the strategy chosen.) A good benchmark that many use today is 3%, three mites on one hundred bees (9 mites in 300 bees/1 deciliter of bees).

It also means that to develop a bee stock towards better varroa resistance, you don’t treat against the mite, especially below a mite level of 3%, whenever in the season it is measured.

But if there are wingless bees in the bee colony? It’s usually a sign of DWV and thus too many mites. Here is the Bee Shaker again a good tool, to find out if there really is a high degree of infestation of mites when you see a wingless bee. If you decide to treat against mites if the level is high you might do it to prevent the spread of mites to other colonies nearby.

 

A colony with a wingless bee

Last year’s breeder queens seem to have produced many queens that have given colonies that control the mites quite well. One of these daughter queens was introduced to a colony that had problems with mites. Perhaps the biggest problem was virus.

This colony was quite weak in this spring and developed slowly, compared to the other colonies in the apiary. I concluded that I would have to check the brood nest to find out the cause. Maybe the colony was shifting their queen?

On a later visit to the apiary about June 20, I saw one, only one, wingless live bee on the hard board in front of the entrance. I then looked in the brood nest, but saw no more wingless bees on the brood frames. But the brood frames had a so called shot gun pattern with a lot of “holes” where you would have expected capped brood as the other cells on the comb contained capped brood. Many pupae seemed to have been removed by the bees. Most likely not due to inbreeding as the queen had mated in the apiary and the number Elgon colonies in the neighborhood was quite high. No trace of any brood disease could be seen so I concluded that a likely cause could be cleaning out of varroa-infested brood. Or could the bees detect virus in the pupae and remove it, without there being a mite in the cell, and remove the pupae?

Could that be the reason why the colony developed so slowly – that the bees were throwing out mites? How had they managed? The wingless bee could indicate that they had not done so well and that the amount of mites was big. Now it was time for a Bee Shaker test to find out the level of Varroa infestation. (Here you can read more about The Bee Shaker, its uses and possibilities: http://www.elgon.es/diary/?p=809)

Here you can see a video clip when doing this test (sorry I’m talking my mother tounge Swedish):

The sample showed zero (0) mites! Then it’s no use to treat, There were far too few mites in the colony. Why had there been a wingless bee recently before the test?

VarroaVirus The brood frames looked less spotty and the colony stronger.

July 8 I was visiting the apiary again. Once again I saw a wingless bee on the hardboard. But now I knew the Varroa level was low. Still no use treating. I looked in the brood nest. The colony was a little stronger still and the brood frames had fewer “holes”. The bees look healthy. They were recovering.

Virus apparently remain in the colony for a while after mites are eradicated – by the beekeeper or the bees.