Bee colony decimation in upper volga (Veniamin Novikov)

Bee colony decimation in upper volga.

The beekeeping season of 2007 was not rewarding for beekeepers in the city of Yaroslavl, Russia. Considerable losses of bee colonies were registered throughout the region, with several apiaries totally or partially died off. Affected was not just Yaroslavl region but neighboring regions of Vologodsk, Kostroma and Ivanovo as well. Similar tragedies were registered in some other regions, though less tragic, but no less significant.

Simultaneously, some press publications on the bee colony decimation and even catastrophic die-offs of bees appeared in western countries. The USA lost about 70 percent of bee colonies in the eastern states and around 60 percent in the western states. Such European countries as Greece, Italy, Spain, Portugal, Germany, and Switzerland were also affected, as well as the south-west of England, Scotland and Wales in Great Britain.

I am not going to address problems in the West; there are enough issues in Russia. Neither am I going to touch upon other Russian regions. I am going to concentrate on a specific area in Yaroslavl region. Above-mentioned are three neighboring regions that have similar climatic and weather conditions and a honey-yielding base as Yaroslavl region. One might suppose that the reasons for their bee colony losses were similar.

The honey yield in Yaroslavl in 2007 was half lower than usual. The agricultural fair Honey Feast that took place in Yaroslavl in March 2008 did not host a single exhibiting beekeeper from Yaroslavl due to a mundane reason. They simply had nothing to sell. To make matters worse, bees started to disappear in late August and September. It did not resemble a bees’ departure when a bee colony that is weak or has lost its queen bee abandons the nest and dissolves in other bee colonies. Beekeepers claim that bees literally disappeared. Different reasons, including inconceivable ones, were put forward. The topic turned into a hot discussion in the United Beekeepers’ Forum. However, facts were not enough to infer the reasons.

Almost all beekeepers in Yaroslavl region have now counted their losses and revised their bee colony numbers. There is some data that allows making a few conclusions. Below are sample statistics gathered by the village council of Velikoe Selo, Tutaev district. My choice of the statistics was due to the fact that I have been to almost all the apiaries and met their owners, I know the number of bee colonies, beekeeping conditions and losses.
Velikoe Selo – 3 apiaries, 40 bee colonies. 5 colonies left.

Runovskoe – an apiary of 25 bee colonies. 2 or 3 left.

Stoyanovo – an apiary of 14 bee colonies. One left.

Tsvetkovo – 2 apiaries, 17 bee colonies. 3 colonies left.

Barinovo – an apiary of 32 bee colonies. 2 left.

Aksyontsevo – 3 apiaries, 22 bee colonies. 18 colonies left.

Out of the total number of 150 only 33 bee colonies survived.

Let us consider some of the possible reasons for the decimation. The list is as follows:
• Varroa mites;

• weather conditions;

• disease (a known or an unknown one);

• mobile telecommunications;

• divine forces.
I would like to start with the last point. Although, to my mind, it is quite probable, divine forces as a reason for the decimation might not seem likely to beekeepers-atheists. Besides that, it is beyond our expertise, and its hardly possible influence is global. Let us leave it aside the article (though keeping in mind the core of our existence) and turn to more down-to-earth factors.

If mobile telecommunications affected bees, the impact is barely noticeable. The argument is that mobile telecommunications have been in use in Russia for a few years now and in the West for decades. The recent tragedy with bees burst out for the first time in the history of mobile telecommunications. The die-off cases registered earlier had been thoroughly studied and explained. Nonetheless, I kept in mind the possibility while collecting facts and attempted to analyze them. The die-offs of bee colonies were registered in the proximity of retranslating towers and in locations where no towers were erected. For example, Velikoe Selo put the blame on their retranslating tower. However, the tower is not in operation and might do as much damage as an exhaust pipe of a boiler room.

Now over to the disease factor. A sample of bees was taken to a regional veterinary lab. No serious disease was detected in the sample, as the official conclusion went. There still exists a possibility of a new and not-yet-researched disease, but such a possibility is very unlikely, given the remoteness of developed agricultural regions. The arrival of such a disease is even less likely, although it is essential to consider this factor in the future.

Thus, there are two factors left: the Varroa mite and the weather. It is the Varroa mite that is believed to be at least one of the reasons for the tragedy, if not the main reason. Both the results of the spring audit and the analysis of the 2007 weather conditions support this assumption.

Before moving to any further search for the reason for the bee colony decimation, I suggest we turn to another matter. I would like to take a brief look into the reasons of the poor honey harvest in 2007. It would allow studying the monthly weather charts of 2007. The charts will be required to investigate the reasons for the die-offs of bees. The honey harvest was low in the southern parts of Russia, which is explained by droughts. What happened in Yaroslavl then?

The early arrival of spring 2007 in Yaroslavl forced beekeepers to put out their hives two or three weeks ahead of the usual schedule, on 20-22 March 2007 (see chart March-April). It was then that thoroughly checked, packaged and insulated bee colonies commenced their development. April’s low temperatures did not allow a proper honey flow from the willow that regularly yielded good amounts of commercial honey. Warm days were scarce in April; thus the main carbohydrates were last year’s honey supplies. Besides last year’s supplies, proteins were sufficient due to alder, hazel and willow trees. Pollen was always in abundance here.

The cool weather forced a large number of bees to work inside their hives, and bee colonies grew fast. Where only a few bee colonies used to be ready to swarm (or ready to divide colonies and make nuclei) by mid-May, all colonies were ready to swarm by that time in 2007. The swarming could have been slowed down by the honey flow in gardens, but it was very rainy at that time. The very high temperatures of the second half of May also produced a positive impact on the faster swarming. Almost all apiaries where bees can swarm freely, which are in majority in villages, were swarming. (see chart May).

Late May and the first half of June in Yaroslavl region is the time when bees do not fly out. To be precise, not a half of June, rather 20 or even 25 days. Honey gathering is only possible from acacia trees and daisies at that time, with acacia trees being few in number and daisies producing a lot of pollen but little nectar. Being at the peak of their activity, bee swarms were in a tough situation and, as I presume, had to decelerate their brood growth. The number of worker bees that had to fly out was too big. What is more, it was 9 days of non-stop raining. Other areas might have had rain on other days, but the trend was overall the same.

To top it all, five days were showery and three days were rainy out of the last eight days in June that mark the start of honey-gathering (see chart June).

Rainy days carried well into July. Although the air temperature was high enough, one should agree that 19 rainy days in a month is not good for honey flow (see chart July). Some notes from a diary: “July 2nd. What a shame! It has been a week that the rain will not stop”; “July 12th. The first day without rain and it is so hot. Linden will yield nothing”. Indeed, it did not yield anything. Linden trees rarely yield honey; nonetheless, its honey flow is good enough to sustain bees.

There came August. It was raining on warm days and extremely hot on other days when no flower or plant, not even the strong meadow knapweed, would yield nectar (see chart August).

As a proverb goes, “A beekeeper shall never have a bad year”. It is true but, unfortunately, only partly. There are years when a beekeeper’s skills can minimize losses but never avoid them. 2007 is an example. Some beekeepers bought commercial honey, though in much smaller quantities. Other bought a little, whereas the rest did not buy any. Luckily, there was no need to feed bees. We will later comment on those beekeepers that extracted more honey than required and hence had to feed bees with syrup.

Therefore, one of the reasons for the poor honey harvest was a force major in the form of weather conditions. The second reason, as you might have already guessed, was the Varroa mite. A combination of the both reasons did not allow proper commercial honey yield. Additionally, they had a direct negative impact on bee colonies that resulted in their decimation.

Let us turn back to the main subject of the article, using the charts where required.

As mentioned above, bee colonies needed to make considerable additional efforts (as well as to have additional number of bees) to collect enough honey supplies in such unfavorable conditions. Although it takes place during the honey harvest in any year, a reduction in the number of bees in bee colonies was particularly high in 2007. Bees would have been able to deal with the situation if it had not been for the disastrous Varroa mite.

The exceptionally early spring and the exceptionally hot August created favorable conditions for all insects to produce more brood. People who go to the forest noticed how early and in what abundance different mites, ticks and lice emerged; how many fleas were found in houses and apartments. For example, insecticides were constantly sold out in stores of Tutaev.

The Varroa mite was no exception. The mite was found in August in apiaries where beekeepers had performed the spring clean-up of beehives. What could one expect to see in apiaries where the clean-up had not been done? Beekeepers that replaced winter trays a few days after the hives had been put out discovered an astonishing number of dead Varroa mites. Frankly speaking, it was the first time in my life I had ever seen anything like that. This all was despite the fact that the beekeeper treated each nest with a mite insecticide in spring 2007. The same treatment was performed in the previous autumn but a bit late. The straps treated with the insecticide were left in the hive till next spring, and the trays were not cleaned up before the overwintering.

Experienced beekeepers remember the year of 1978, when almost all apiaries were affected by the Varroa mite and bees died out in populated beekeeping areas. Only a few bee colonies survived, and beekeepers had to divide them among each other and build up on swarms. As a matter of fact, bee swarms were not sold but given out free of charge (oh, the good old times).

It was the Varroa mite that finished off bees that had already been weakened by the poor honey harvest. Even if one assumes that a queen bee started to lay as many eggs as it could, the mite would kill the major part of the brood and the rest of it would cease to live. Bee colonies never flew away anywhere. It was the queen bee that left and never returned, as it always does. And there was no replacement for it. That is why hives with enough fodder supplies lost all or most of their bees, a fact that was recorded by all beekeepers that lost bee colonies.

Now I would like to turn back to beekeepers that feed their bees with sugar syrup. I will not bore you with my contemplation of positive or negative sides of autumn feeding. Beekeepers are well informed about that. I want to emphasize that the feeding became the last drop in that particular situation. Even those bee colonies that had a hypothetical chance to survive were doomed. They died off the last, during their overwintering. No other objective reason for their die-off in winter could be found.

There was enough fodder.

September temperatures were quite moderate according to early autumn averages. Rainy days were not many. (see chart September).

The first week of October was warm, and bee colonies were able to take the last fly-out quite late in autumn (see chart October).

The winter was mild, even outdoor overwintering did not cause too much damage to bee colonies. There only were 22 days with temperatures below 16 degrees Celsius. It was a little damp. But one could say the microclimate in bee houses was ideal.

It is time to draw conclusions, although they are clear for everyone to see. Everyone will make their own conclusions.

My conclusions are merely mine. I am just a man and may be wrong. I might have made a wrong conclusion. But it seems quite unlikely.

The bad weather was an important factor, because if it had been for the weather, the mite would not have appeared in such great numbers. Nonetheless, beekeepers played the critical part. It was beekeepers who had not paid enough attention to anti-mite treatments and thus caused the disastrous spread of the Varroa mite and, as a result, the die-offs of bee colonies.

P.S. Albert Einstein, the prominent scientist, once predicted if honeybees died off, then human beings would only have four years to live.

Regretfully, I cannot discuss the article by correspondence: The beekeeping season has already started, and I will be busy with bees. I would like to invite all interested parties to the United Beekeepers’ Forum for discussion. Your ideas and contributions are highly welcome there.

Veniamin Novikov

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