In the frameworks of our Apivox Varroa Eliminator project, we continue to review and analyze the state of the bee's families and the mite's population living in this families, using the method of counting free fall of the mites on sticky board, and we believe that this method, although it does not yet allow one hundred percent accurate numerical data, can help to determine key points in the development of bee's families and the population of mites parasitizing on them.
For a long time scientists tried to adapt such a parameter as the mites drop, for prediction of the degree of mites, parasitizing on the bees in the colonies ... But everyone wanted to get specific numerical data, even by simply adjusting the numbers to the needed results ...
On
the basis of this method, the ministries of agriculture of the
It is believed, that it gives fairly accurate results. But sometimes it's not quite right, and sometimes it's not right at all .... We came to this conclusion for two reasons:
The first reason - is that in different works of scientists, who studied and evaluated the accuracy of all known methods of calculating of the quantity of Varroa mites in bees families, it is written, that all methods are equally not accurate at the beginning and at the end of season, when the number of mites in the family is too small. And that in these works, scientists use at least three different coefficients to translate the amount of daily free fall of mites, into the total number of mites in the family of bees. We know that scientists use this special coefficient, by which, the average daily fall of mites is multiplied ... It is equal to :
2) 120 throughout the season. (Development of the mite, Varroa jacobsoni oud., in the honeybee, Apis mellifera L., in Michigan, USA, and a comparison of diagnostic methods for detection of the mites Ahmad Al Ghamdi and Roger Hoopingarner )
3) 170-200 throughout the season. (GUÍA TÉCNICA PARA
PARA LA LUCHA Y CONTROL DE LA VARROOSIS Y USO RESPONSABLE DE MEDICAMENTOS
VETERINARIOS CONTRA LA VARROA DIRECCIÓN
GENERAL DE SANIDAD DE LA PRODUCCIÓN AGRARIA
SUBDIRECCIÓN GENERAL DE SANIDAD E HIGIENE ANIMAL Y TRAZABILIDAD)
This already suggests, that each researcher adjusted the coefficient to the situation in his apiary, or in his zone. And even this fitting does not work if used in mathematical models, which are compared then, with the real results of counting of Varroa mites in the brood and on adult bees... (Population growth of Varroa destructor (Acari: Varroidae) in honey bee colonies is affected by the number of foragers with mites Gloria DeGrandi-Hoffman Fabiana Ahumada Victor Zazueta Mona Chambers Geoffrey Hidalgo Emily Watkins deJong)
It must be said, that counting of a quantity of mites, using another methods is not much better ... Counting the quantity of mites, parasityzing on adult bees is not indicative since in summer, up to 70% of the mites are situated in the sealed brood... analysis of the sealed brood are not accurate due to the uneven distribution of the mites in the brood and due to the presence of a part of the mites on adult bees ...
Calculation of the percentage of mites in any form is also not an indicator... With different strengths of bee families, the same percentage can mean a multiple difference in the real number of mites, which, in the process of development of bee families and reproduction of mites, leads to a multiple difference in the percentage of mites when the strength of bee families will become equal...
For our project we invented our own method of calculating of mites drop. It consists in a separate count of dark - old, already participated in reproduction females, and pale-colored young female mites and deutonymphs, which died or did not fertilized by a male mite inside the cells, and were thrown out by the bees. We call this the two-graph method. So, what is its meaning ...
They all have a different color !!! Mature old fertilized females are deep red and burgundy! Young females have a bright red color that is darker or lighter depending on maturity, and the paler ones are not mature females and transparent individuals are deutonymphs ... In order to find this facts, we had to turn to authoritative documents ....
On the diagram we see once again the confirmation of our practical results - 1) Varroa mites in the summer live 2-3 months. In practice, we see about 2.5-3 months. 2) Immature and not fertilized young females do not survive. 3) The final red-brown color of Varroa mites is gained after the last molt ot the mite, when it become fully grown and capable to lay eggs. Young females does not have such a color. They are paler. The color is closer to brigh-red. Confirmation of this item we took from another document ...
(A deadly honey bee parasite The Varroa Mite PUBLISHED BY Bayer AG beecare@bayer.com www.beecare.bayer.com )
"...Graphic showing Varroa mite development stages The first development stage of the Varroa mite is a six-legged larva that develops inside its closed egg. The eight-legged protonymph emerges in the post-hatching second stage. In the third phase this protonymph develops into a deutonymph, which then becomes the adult mite. In the final nymph phase, the growing mite undergoes two immobile transitional chrysalis stages (protoand deutochrysalis). Young female nymphs are white in color and, after molting several times during the development process, turn dark reddish-brown during the last immobile stage – the deutochrysalis – and maintain this color as adult Varroa mites..."
So, the method of two graphs that we use, assumes separate counting of dead old females of the mites, dying during or after breeding, and dead young females, that did not participate in breeding. Shifting back the graph of mites drop of mature dark mites by 2.5-3 months, or by the approximate lifespan of the tick, we can talk about the approximate time of their birth, and we can analyze the events, that led to their appearance and development in the bee colony. The appearance of the mite's drop, consists of pale mites is, according to our long-term observations, a very bad sign, and speaks of an over-intensive reproduction of the mites, when it uses all brood zones for reproduction, even that are not too suitable for reproduction in terms of their parameters. Thus, using two graphs, we can learn about the past of the mite's population, about the prospects for its increase in future, and about the intensity of the process of growth of the mite's population at the moment.
In general, free fall of the mites at the time of testing is not always indicative. There are intervals, as we can see from the graphs, when there is practically no mite's drop or it is small ... This does not mean that there is no mites or its number is small... It is just mean, that the mites are waiting for suitable conditions for mass reproduction.
From the
graphs we can see, that the mass death of the mites of all ages is directly
related to the cycles of enhanced reproduction, which apparently takes away the
last strength from the old individuals and leads to their death... In this case, the idea that the mites live
for about 2-3 months and the method of shifting the graph of free fall of the
mites by 2-3 months back shows the time
of their birth, allows us to see the real time of birth of this mass of falling
mites ... And these are the months, when it seemed to us, that there was almost
no mites or very few... In particular,
so was in January-February 2020, as can be seen from the graphs below ...
The graph of free fall of the mites (mites per day) in 4 families of our experimental apiary during 2019-2020 years
An analysis of the graphs of free fall of the mites obtained by us during 1.5 years of continuous observations of 4 families of bees, shows the following ...
Almost throughout the winter, except November and December, the mite population had the opportunity to reproduce and maintain its existence, since the bees had brood due to the warm winter and wintering in a pavilion heating by the sun. This led to the fact, that the first massive release of new mites and the fall of old and immature mites coincided with the honey harvest from the willow on about April 23rd. The influx of large volumes of nectar and pollen led to the first mass release of young bees from the brood, and accordingly, to the first powerful release of the mites. The second release took place at pre-swarming time from 11 to 30 May, when the number of brood at least doubled, and was laid drone brood. All these led to the next outbreak of the mites population.
In colonies 5-1 and 5-2, the growth of the mite's population during the main honey gathering stopped due to a reduction in brood quantity due to the filling of the nest with honey, but at the end of it, the mites began to reproduce again. The family 5-1 lost its queen and was left without open brood for a couple of weeks. The mites drop in it has grown quite insignificantly, and then it sharply decreased. But in the 5-2 family, at the end of honey harvest, free fall of the mites of all ages again sharply increased to close to critical values.
In the E-1 hive, the growth of the mite's population was so strong that, when the swarming began, it led to a complete loss of the family. The reason is that this family with an old queen had already laid swarming queen cells by May 7. The sharp increase in the amount of well-heated brood resulted in a powerful increase in the mite's population. As a result, in the family, there were a lot of sick and dead larvae in the brood, and sick young bees. All infected brood was abandoned. The family, despite the removal of swarming queen cells and the division in half, flew away in the form of two swarms.
In the hive 8-1, a similar picture began with some lag behind E-1. The bees of this family also laid swarming queen cells, but the queen in this family was young, and the removal of queen cells led to the termination of the swarming mood of the family. Despite this, it was laid a lot of drone brood , which caused the subsequent increase in the mite's population. The growth of the mite's population began in this family too, but a little bit later, on the background of honey collection, since the family was not quite ready for it and began to bring marketable honey later than 5-1 and 5-2 ... In order not to lose the family, were taken a measures, as you can see on the graph, on June 23. One frame of drone brood was removed and was completely destroyed drone brood on all other frames. The fall of immature and mature mites dropped sharply. This indicates the possibility of temporarily suppressing of the development of mite's population in pre-swarming time by removing the maximum amount of drone brood. But at the end of the honey harvest, the mites were able to develop vigorously again, and the fall of the mites of all types increased sharply to close to critical values.
So, what did our observations show in general ...
1) Observations show on the example of all families, that each next burst of the mite's reproduction is at least 2-3 times stronger than the previous one. This difference roughly corresponds to the amount of mature mites fallen free during the present reproductive cycle, divided by the amount of fallen free immature mites of the previous reproductive cycle... The value is approximate, but it is confirmed in all experimental families. You can see it on the graph.
2) Observations show that swarming state of bees should be avoided by all means. It is the massive laying of drone and bee brood before swarming and, most importantly, its thorough heating by the bees, that leads to a catastrophic increase in the mite's population due to a multiple increase in the reproductive territory, comfortable for it.
What
happens in this case with the bee family? Let's have
a look...
In the course of our scientific work and acoustic monitoring of bee colonies using our Apivox Smart Monitor device, we came to understanding, of the changes, that occur in the bee nest in pre-swarming period ...
The fact is that at the beginning of the process of preparing for the swarming, the task of the family and the queen is to build up the maximum possible strength of the family before the swarm leaves. Then, dividing in two, the family will remain large enough to survive and collect honey for the wintering. To do this, the queen begins to fill all the cells in the hive suitable for this with brood ... But the nest is not the whole hive, and the bees do the following !! They start powerful heating of the ENTIRE hive ! The whole hive turns into a nest! The earliest queen cells appear on the periphery of the nest - on the second frames after the extreme honey frames ... It was at this moment when a specific acoustic signal appears in the hive, which we use as a sign of an impending swarming, which Woods considered to be a signal of young bees, and prof. Eskov mistakenly considered to be a signal of passive bees .... A signal, that accompanies heating of the hive and a signal that accompanies heating and aeration of open brood. These signals becomes so powerful, that they dominates in the hive even in the daytime, suppressing the signals associated with the work of bees on honey harvest!
This event in the life of a family of bees becomes the "golden" time for Varroa mites and the cause of the subsequent troubles of bees ... down to their death .... Now the mites can actively reproduce in a huge amount of brood, and not only in brood of worker bees, which used to be warm enough even earlier, and also to reproduce actively in drone brood... This at least doubles their breeding potential, which ultimately leads to exponential growth of the mite's population in April-June.
Such a leap in the growth of the mite's population occurs primarily in the families, which are initially ready for swarming - that is, in the families with old queens. It is possible, that this was the reason for the confidence of many beekeepers that bee families with young queens are better able to cope with the mites. But it is normal thing, in the families with young queens, bees are less prone to swarming, which means, that they are less prone to heating the entire hive and to the massive construction of drone cells, which become a "bomb" placed under the colony during swarming time. In normal times, drone brood located in cool areas of the hive does not create such an "incubator" for the mites, and colonies that do not enter the swarming state suffer from the mites much less.
The use of anti-mite's techniques associated with expansion and, as a consequence, with cooling of the nest, will worsen the mite's reproductive capabilities and, possibly, save the bees from death in the event of a high infection of the bee's colonies in spring.
Basing on this, we can say, that in springtime, early diagnosis of swarming state of bee colonies become a very important point for a beekeeper who want to get ecologically pure honey. Using Apivox Smart Monitor application, you will be able to know about it at least 2 weeks before the start of the swarming process, or even earlier, and will be able to understand, that it is high time to take measures, which will not only help to avoid losing of swarms and honey, but will also dramatically reduce the number of mites in bee colonies.
3) Observations show that if, during the next cycle of enhanced reproduction, free fall of an immature mites significantly exceeds free fall of an old mature dark mites, and has sufficiently large values, then this is a very alarming signal. It can be assumed, that not only a large number of young mites were released, but the founding females did not die ! Thanks to this, accumulates the mass of live mites, ready to participate in the new reproductive cycle, and exactly this make the next flash of reproduction so powerful.
During the main honey flow period, when the mites have less bee's brood in the nest for reproduction and worsening climatic conditions in the nest, overall reproductive opportunities of the mites reduces. Free fall of the mites sharply reduces or stops altogether ... The mites of reproductive age are waiting for the optimal moment to start laying eggs ... With a decrease in the flow of honey at the end of the main honey harvest, as well as with removal of honey by beekeepers at the end of summer, the volume of free space for laying eggs by the queen increases ... The weather conditions at this time, in August-September, are still favorable for the bee's brood rearing and for the mite's reproduction. At this time, beekeepers are trying to get as many young bees as possible, because exactly these bees will winter and form a family next year. Under these conditions, starts new powerful laying of brood by the mites, which, as a rule, leads to a powerful autumn surge of the mites population, and during release of young bees from the cells, to a strong fall of old mature females, and immature young female mites.
All this can be seen in the diagrams for families E-1 and 5-1.5-2. It was in the E-1 family, which showed the greatest growthof free fall of pale immature mites, and as a result, a sharp increase in the mites population till a critical numbers. This led to the loss of the family. In families 5-1 and 5-2, the number of immature mites falling free on sticky board was significantly less, and it needed about two months for the mite's population, to grow to almost the same size as in the E-1 family.
4) Observations show, that the state of a bee colony when a quantity of falling mature mites reaches quantity up to 5 mites per day, in principle, is not too bad for a colony of bees of almost any strength. The bees of a strong family can even withstand situation, when a quantity of falling mature mites reaches 60-70 mites per day, for up to a month. They are also can withstand situation when a quantity of falling mature mites reaches from 20 to 40 ticks per day, for 2-3 months. Of course, in the bee's family appear many damaged bees that are unable to fly, and this weakens the family and reduces its honey productivity... We can see such a situation in the graphs of three families of our experimental apiary - 5-1, 5-2, 8-1. At the same time, 8-1 and 5-1 produced about 40 kilograms of marketable honey, and a 5-2 family - 60 kilograms, while being in a stationary apiary. Thus, we can say, that the state of a bee colony when a quantity of falling mature mites reaches quantity up to 10 mites per day, in principle, is not terrible in the short term for a strong colony of bees. The danger appears when, in addition to mature dark-colored mites, immature pale-colored mites appear on sticky board. This is a signal of alarm. This is a sign of an incipient reproductive "outbreak" of the mites. So, as you can imagine, the main task of beekeeper is to combat these periodic reproductive outbreaks! Their suppression should be the main task.
What methods can be used for this... Let's consider these methods in chronological order in accordance with the life of bees ...
Wintering:
The first step in keeping bees properly in terms of Varroa mites control
- is cold wintering. This method has been known in
It is ideal, if bees, especially Carnica bees, begin to actively rear brood with the arrival of stable heat and appearance of pollen sources in nature. It is from this moment and not earlier begins the active development of bee families . At this time, if the bees have warm nest and are supplied with nectar and pollen, they build up their strength surprisingly quickly, especially in the case of the bees of Carnica breed.
In other
case, exactly population of Varroa mites, rather than the population of the
bees, develops and renews better. That is why in
Spring development till the main honey flow: The main methods of influencing the mites population in this period are: the reduction of the space suitable for the reproduction of the mites and the deterioration of the conditions, required for their reproduction. Several techniques can be involved here together or separately ...
1) Creation and maintenance of young families. Creating young families in the apiary to replace old working families by forming artificial swarms, by forming offshoots with mature queen cells, the beekeeper "kills two birds with one stone at once." Firstly - when creating such families, the brood which at this time is the main repository of the mites, is not used or is used minimally. Secondly - such colonies are easy to process in any way, including using of formic acid, which is a method, that minimally contaminates frames and honey. Thirdly - the families will have young queens, which is an excellent anti-swarming technique. Such families, as a rule, have a good start in development and begin wintering healthy and clean.
2) Suppression of swarming state of the bees in order to deprive the mites possibility of super-active reproduction in a huge amount of well-heated brood of worker bees and drones. Before the start of the main honey collection, possible methods are: the presence of young queens, expansion of the nest, removal of maximum possible amount of drone brood. Firstly, as we have already said, colonies with young queens are, in principle, much less prone to swarming. Secondly, the expansion of the nest reduces swarming mood of worker bees and deprives mites of a large, well-heated brood zone and, most importantly, a well-heated drone brood. Thirdly, the use of building frames allows not only to reduce swarming mood of the bees, but also to remove from the hive and destroy almost ninety percent of drone brood with mites in it, with a minimum expenditure of efforts and without injuring the bee family.
3) Removal of sealed brood. Removal of frames with sealed brood, which can be carried out during the period of bee's families growth, till the main honey collection, in order to prevent swarming and to create offshoots, also sharply reduces the number of mites in bee colonies, and significantly contributes to the fact, that the disease does not take on a threatening character in the main colonies until autumn, even in the absence of other mites control measures. In addition, holding such an event in June can, under certain conditions, increase honey productivity of bee's families by reducing number of bees engaged in brood rearing. At the same time, the families from which the brood was removed, can be treated with formic acid, and this treatment will be very effective at this stage.
In the process of honey collection, bees themselves usually create conditions, which are not very good for the mites reproduction ... This can be seen from the graphs of free fall of the mites in all four families. ( June-mid of July) But even at this time, it is possible to influence the mite population using methods of temporary limitation of queen egg laying, and removal of sealed brood. Unfortunately, such measures during the period of honey collection cannot be radical, otherwise there will be losses of marketable honey due to weakening of the strength of bee colonies.
Autumn preparation of bee families for wintering. It is possible that you can again use the method of removing the sealed brood, and then proceed to cooling the nest, in order to stimulate the end of brood rearing season. In this case, the first task is to interrupt the mite reproduction chain in working family. Using this method, beekeeper can remove most young mites and founding females into a separate colony, which will be a subject of radical anti-mites treatment after the entire brood will release. At the same time, in all families from which the brood will be taken, should be given new combs, in which the queens will begin to lay eggs, from which will born the bees, which will go wintering strong and healthy. At the same time, a huge number of mites will be removed from working bee colonies, and will not be able to start a new reproduction cycle. This should be done at the very beginning of the growth of peaks of free fall of the immature mites, which means, that a lot of mites already entered the brood cells for reproduction. The second task is to ensure a smooth transition of colonies to cold wintering with corresponding decrease and further termination of brood rearing.
The use of our new Apivox Varroa Eliminator project and a new method of keeping bees takes a special place. Using this method, we managed, although not to completely suppress the development of the mites population in the experimental family, but to reduce significantly their growth rates in summer ... Today we believe, that the design of the hive, although correct, is still not optimal. But even today it has certain advantages ...
- Its
design makes it easy to control the mites drop, in order to understand the
processes occurring in the mites population.
- Its
design allows to ensure the autumn transition to the winter regime and cold
wintering of bees, as well as their warming in the spring and summer.
- Its design allows to accelerate the development of families in spring and summer, while reducing the intensity of mites reproduction.
An analysis of data from the past 2019 showed, that if we can consider free fall of the mites proportional to their number in the bee colony, or to the size of the mites population, then, the growth rate of the mites population in the experimental hive number E-1 did not exceed six times, despite the fact that the family had an old queen bee and a lot brood, while control colonies, some of which had young queens born in this year, and which had less mites, had growth rates from ten to one hundred times... In this case, we are talking about relative values. The absolute values of free fall of the mites in experimental family were initially higher than in the control families, but by the fall these values were almost equal ... In the end, not the design of the hive led to the death of experimental family, but the need to conduct observations of the development of the mites population in it even till its death!
In general, new hive showed that the bees can live and develop in it, and we can select its parameters in order to suppress the development of Varroa mites to one degree or another. But this will have to be done again next season, in order to obtain more statistically reliable results.
So, we are confident that application of the above rules of keeping bees throughout the year and the use of our new hive will be able to jointly solve the problem of preserving bees and of suppressing the development of Varroa mites in their families.
Here we used diagrams and drawings from the works:
1.
Population model for the ectoparasitic mite
Varroa jacobsoni in honey bee (Apis mellifera) colonies Stephen Martin National Bee Unit, Central Science
Laboratory, Sand Hutton,
2.
Development of the mite, Varroa jacobsoni oud.,
in the honeybee, Apis mellifera L., in Michigan, USA, and a comparison of
diagnostic methods for detection of the mites Ahmad Al Ghamdi and Roger
Hoopingarner
3.
GUÍA TÉCNICA PARA PARA LA
LUCHA Y CONTROL DE LA VARROOSIS Y USO RESPONSABLE DE MEDICAMENTOS VETERINARIOS
CONTRA LA VARROA DIRECCIÓN GENERAL DE
SANIDAD DE LA PRODUCCIÓN AGRARIA
SUBDIRECCIÓN GENERAL DE SANIDAD E HIGIENE ANIMAL Y TRAZABILIDAD
4.
Population growth of Varroa destructor (Acari:
Varroidae) in honey bee colonies is affected by the number of foragers with
mites Gloria DeGrandi-Hoffman Fabiana
Ahumada Victor Zazueta Mona Chambers
Geoffrey Hidalgo Emily Watkins deJong
5.
A deadly honey bee parasite, the Varroa
mite. PUBLISHED BY Bayer AG
Copyright Sergey Glebskij 2020
© All rights reserved
https://sites.google.com/view/apivox-varroa-eliminator-eng/results-years-2019-2020
