I’m hearing that hives loses for many beekeepers in the area are much greater than in past years. I can agree with that observation.
As part of reclaiming my dead hives, I looked a bit harder than normal and found some interesting results. Although I don’t like loosing bees, learning from all the excellent information available softens the blow.
I’ve used formic acid in the spring and had reasonably good results. I have routinely treated with Apiguard™ (thymol in gel formula), in late summer and also had good fall mite control. Looking at the 2017 results, I think got lulled into a false sense of effectiveness and hope to do two (or more) things differently this year.
First, I’m going to switch to the formulation in Apilifevar™ for late summer as some studies indicate it to be less dependent on temperature. It is always a good idea to mix treatment although the active ingredient is the same. I’ve never used it before but have had reports that it works well.
Second, I hope to be more aggressive at using mite counting techniques to keep better records of mite buildup. It is possible that a combination of the treatment not working well and the mite population having some environmental advantage that I simply missed caused the larger losses
That’s beekeeping. Time to make splits!
In reviewing the data, it was brutally cold this past year with weeks below freezing and sometimes below zero in December and January. An observed high mite concentration in January would result in a pattern of continued weakening of winter bees. They looked like they were going about their winter business but ended up head down in the cells indicating starvation. The queen was present with nectar very near by the cluster. It appears that the cluster was not large enough or had the combined energy (critical mass) to sustain winter operations and keep the cluster alive from all the dead bees in the bottom board. It is a good strategy to look at the approach to addressing PMS moving into winter, the volatility of thymol and continuing to look at techniques to more aggressively monitor mite population, Great Approach.