Friday, November 28, 2008

Tubes Bottom Boards Improve Beehive Product Quality

By Jean-Pierre LE PABIC

[Editor’s Note: This presentation is part of the Second National Apitherapy Congress, Expo and Workshops with International Participation held November 21-24, 2008, in Iasi, Romania.]

1 – Introduction

The tubes bottom board has been available for sale in France since 2002. Having previously used it for nearly a decade at that time, I had the conviction that it was useful for the bees, mainly in helping them to combat Varroa mites but also for fostering a more populous colony in spring. That is why I took the gamble to produce it and propose it to beekeepers.

A great deal of information flowed from the keepers using the tubes boards. Some observations only served to confirm my experiences but some others were new and then good surprises.

All of the field work evolved into conducting comparative experiments under protocol to confirm or disproof beekeepers observations and eventually to quantify each point. The results were very positive.

Many questions remain unanswered, especially as to the means by which the tubes bottom board gets its efficiency. For some questions, we can venture a hypothesis, for others we are not yet ready.

Future experiments will have to provide more information about the way the tubes bottom board works but will also show more on the bees colonies themselves.

2 - Description of the Tubes Bottom Board

The tubes bottom board consists of: a wooden frame; several tubes; and three struts. The tubes are held in place by the struts. The gaps between the tubes are about 3.5 mm. Bees cannot pass through them. Hive waste as well as Varroa mites fall through the funnel shaped openings and can be examined under the hive.

3 – History of the Tubes Bottom Board

The tubes bottom board was invented in 1993 by Marcel Legris, a beekeeper from Marseille in the south of France. At that time, it was discovered that numerous feral bee colonies survived without any anti-Varroa treatment. The belief being that the reason was a certain amount of Varroa mites fell out of the cluster to disappear under the colony in places unvisited by the bees. The tubes bottom board was originally created to reproduce those conditions.

The Legris design was made with rigid tubes fitted into holes recessed into the wooden frame on each side. The tubes were expensive and manufacturing was complicated. The lack of profitability quickly caused Mr. Legris to close the business.

Having purchased some of these boards and using them in my apiary, the positive observations I made compelled me to seek a more affordable design for the board.

This was accomplished in 2002 and allowed me to introduce the new tubes bottom board under the “HAPPYKEEPER” brand name. As already indicated, the tubes are no longer fitted into holes inside the frame but rather held in place by three struts punched from plastic sheets. It was then possible to use less expensive polyethylene tubes on which nothing will stick. Because the tubes are not rigid nor perfectly round, a strut is placed in the middle to keep them parallel.

4 - Beekeepers Observations

The first observation can be easily seen by anybody, preferably in September or October. It was reported to me very early by a beekeeper living near my home. He was desperate. Having a very high mite infestation rate, even though he was using mesh boards. He wanted to try the tubes boards as a last resort. In less than a week he came back telling me that “as soon as he had replaced the mesh boards with the tubes boards, the mite falls increased considerably”. This same observation was reported to me by several other keepers. It cannot however be witnessed at just any time because mite falls occur only from September until April.

The second observation which I was soon told about is the cleanliness of the tubes board in spring. Many beekeepers at first bought only a few tubes boards to try, but this advantage inspired them to quickly equip the rest of their hives.

Regarding the cleanliness of the tubes board, if it is not clean in spring, it means there is something wrong in the colony. Usually it is queenless.

Many beekeepers using the tubes bottom board no longer treat. In my case, not since April 1997 and not in return of a weak colony as may be the case with other kinds of bottom boards. On the contrary. The colonies on tubes bottom boards are reported to be populating earlier and to be stronger in spring.

In my personal apiary, I measured infestations rates about 2 to 3% in spring after a few years without any treatment.

On the other hand, beekeepers who have not dared to stop treatments are not encouraged to do so because their infestation rates do not decrease very much.

The last point to be made is that a beekeeper having his hives at a high altitude in the Alps reported very low temperatures : 3 weeks in January and 3 weeks in February at about -10 °C / 14 F and occasionally at - 15 °C / 5 F. And all his colonies were alive and perfectly healthy in spring on tubes boards.

This collective knowledge was a basis for creating written protocols to carry out experiments which took place in Toulouse from January until October 2005 and in Vesoul from January 2006 until June 2007.

5 - Protocol Controlled Experiments

5.1 - Toulouse Conditions

Climate: In Toulouse, min and max average temperatures in winter are about 2 °C and 10 °C, 36-50 F. In summer they are about 17 °C and 28 °C, 63-82 F. There are about 50 mm of rainfall per month from July until March; about 70 mm from April until June.

Number of colonies: There were ten colonies on tubes boards and ten on mesh boards.

Bees: Bees were Buckfast and queens were sisters.

Last anti-Varroa treatment: Last anti-Varroa treatment was applied in August 2004.

5.2 - Vesoul Conditions

Climate: In Vesoul, min and max average temperatures in winter are about -1 °C / 30 F and 5 °C / 41 F. In summer they are about 15 °C / 59 F and 25 °C / 77 F. There are between 80 and 100 mm / 3-4” of rainfall per month all year round

Number of colonies: There were ten colonies on tubes boards and ten on mesh boards.

Bees: Bees were black bees and queens were sisters.

Last anti-Varroa treatment : Last anti-Varroa treatment was Apivar applied from September until December 2005

5.3 - Outstanding Results

Brood surface in spring: In hives equipped with tubes boards, there was 25% more brood surface in May in Toulouse, and 93% more brood surface in April in Vesoul.

Average honey harvest per hive in spring: There was no honey flow in spring in Toulouse. In Vesoul, the average honey harvest was 3,6 kg with tubes boards; 1,8 kg with mesh boards.

Varroa mite falls: In Toulouse, Varroa mite falls were mainly higher on tubes boards at the beginning of the experiment when the boards were first put in place. No increase of mite falls was observed in September. In Vesoul, they were equal between January and August and 3 times higher on tubes boards from September till January. They were nearly 5 times higher after replacing a mesh board with a tubes board; less than half after replacing a tubes board with a mesh board.

Infestation rates:

Toulouse (Sept 2005)
In Toulouse, infestation rates with tubes boards were from 1.1% to 8%, 5.5% on average.
With mesh boards they were from 5.4% to 20.1%, 8.9% on average.
Vesoul (June 2007)
In Vesoul, infestation rates with tubes boards were from 1.5% to 6.5%, 4.4% on average.
With mesh boards they were from 1.7% to 11.6%, 6.1% on average.
No correlation was found between infestation rates and mite falls.

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6 - Analysis

In my opinion, the key point is the substantial increase in mite falls after replacement of a mesh board with a tubes board. Many beekeepers observations were further validated by the Vesoul trial. Nothing can change in a hive so rapidly, except ventilation. We may then assume that the tubes bottom board is effective because it allows bees to ventilate inside the hive according to their needs and therefore to provide a healthy atmosphere around the cluster, perfectly suited to their needs at the time.

Further studies are necessary to qualify this point.

Although infestation rates are significantly lower with tubes boards, they are not all immediately below 5%, which is the spring infestation rate under which treatments are unnecessary.

These results only serve as the basis for more long term monitoring studies and timely measurements without anti-Varroa treatment to determine stabilizing infestation rates. Further experiments should then meet the following specifications:

- Start in September
- No summer or autumn anti-Varroa treatment before starting. Most treatments are poisonous to bees also and it seems like they weaken the colony in such a way that mites re-infestation occurs faster. It seems that a few years are necessary to reach stabilized infestation rates.
- Measurement of infestation rates each spring over several years.

Being given that I received only positive feedback from beekeepers, there is every reason to be very optimistic about the results. However, in case it should be found necessary, queens breeders could include colony hygienic behavior towards Varroa mites in their selection criteria.

It is often considered that mite falls alone are a good measurement of infestation rates in a colony. It was demonstrated in Vesoul that such is not the case.

It is usually noticed that there is practically no mite fall from May until August on non treated colonies (an increase in September was seen in Vesoul but not in Toulouse). It appears that mite populations increase in summer only to be mostly eradicated in winter. This element should be investigated further.

Another very important advantage is that the bees raise much more brood in spring, resulting in stronger colonies and therefore better harvests.

7 - Some Different Types of Tubes Boards

The first tubes boards sizes were Langstroth / Dadant 10 frames and 12 frames. Struts punched from polypropylene plastic sheets were utilized. Recently the board was enhanced by replacing the punched struts with molded polyethylene struts in the Langstroth / Dadant 10 f board. The enhancement resulted in a more attractive product although functionally equivalent.

A 10 f bottom pollen trap has also been developed. The general problem with this type of pollen trap is that hive waste is mixed with the pollen. Mycosis which have about the same density as the pollen pellets are particularly difficult to eliminate. Moreover, pollen pellets may be stained with sticky hive waste particles.

In the tubes pollen trap, most of the hive waste is eliminated at the rear of the board through the openings between the tubes. Larger pieces of debris are taken outside by the cleaning bees through the drones holes. As a result, pollen contains only very few bee body particles which can be industrially eliminated easily by ventilation while hobbyists can simply use their mouth to blow them away.

Another exclusive to this pollen trap is the rotating pollen comb. By turning it from outside, you put the pollen trap in or out of service. And it is not confusing the bees because their way in or out is always the same.

I have not personally seen any changes in the strength of the colonies nor in Varroa mites infestations compared to the standard bottom board.

8 – Conclusion

We cannot yet say, without reservation, that any and all colonies would stay strong against Varroa mites without any treatment on the tubes board. However, an effective anti-Varroa result was demonstrated in the experiments of Toulouse and Vesoul.

On the other hand, beekeepers observations can be seen as reliable. It is then very likely that an apiary using tubes boards will eventually not need any treatment and enable the production of hive products undoubtedly free of any substance extraneous to the hive.

The ability of the pollen trap to produce pristine pollen is an extra benefit. All of these advantages represent the promise for top shelf, high quality Beehive products for Apitherapy.

A lot of work remains to be done.

The experiments in Toulouse and Vesoul have to be re-done more accurately, for longer periods of time and under various climates. Other parameters of experimentation must be identified and well defined to discover and comprehend exactly how the tubes bottom board functions and eventually to upgrade its design.

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