A Long-Term Observation 2014 – 2015

Groundbreaking observations 10 years ago
By Alois Wallner, Master Beekeeper, Perwarth 7, 3263 Randegg

My question at the time was:

Is the daily natural Varroa waste in the bee colonies usable as a selection feature?

In the search for a new measurement value for varroa resistance, I started the following long-term observation in July 2014.

If this theory is true: less natural waste means less total mite waste, then I would have to recognize a lower susceptibility to varroa with a long-term observation, but it came quite differently...

For observation, two offshoots were formed in May 2014. The queens for these two offshoots came from a people who had already been selected for several years on varroa resistance.

For the preparation of the long-term observation beginning in mid-July 2014, I formed two breeding branches with one mated queen each from my best resistance people.

On the 15. August I singlely demilled both offshoots very easily with formic acid to make the mite infestation reasonably equal, after which the feeding was carried out.

On the 24. August 2024 I started with the daily count of mite waste until the 13th. July 2015, so over 323 days. For a better overview, I summarize the daily figures monthly together with the average daily waste per day and month.

The results monthly:

Summary: 323 observation days of natural mite waste yielded the following overall result:

Among Volk A, 2862 mites fell in 323 days with daily counting.
Among Volk A, 2862 mites fell in 323 days with daily counting.

The comparison: Both queens of the offshoots were descended from the same breeding people. The big difference, with Volk A, fewer mites fell in the same period around 1018 mites than among people B. Now you might think that people A would be even the fewest mites. But the de-mitilation of both peoples starting on the 14th. July 2015 brought a big surprise:

The result:

Among Volk A, 3600 mites fell.
With Volk B but only 1800 mites.

The resistance assessment:

From the daily mite waste alone, no sure judgment on the varroa resistance of a people can be made. Only the ratio of daily mite waste to the actual mite infestation after demilding provides information about the varroa resistance of a bee colony in my breeding. This ratio is called the Varroare Resistance Index. This means that a high daily mite waste can mean both, good varroa resistance or none at all!