I was at the Geneva Bee Conference last weekend. It was a dense, content-rich conference, very informative. Key Speakers were Tom Seeley and Mike Palmer. Here are my take-home lessons of the day:
Quiet winter clusters are preferred to active ones. With a smaller cluster that is less prone to buzzing about, energy is conserved and the colony can make it through winter with less honey.
Hives should be spaced out in the apiary wherever possible. Using wild hives as a model and noting that they are about ½ mile apart, they avoid the transfer of disease and pests. It also helps if they are placed irregularly, not in tidy straight lines like in a big apiary. This reduces innocent drifting from hive to hive and disease transmission is discouraged.
Hives should be elevated however much possible to help prevent pest damage. In nature they like to be up about 15’ but mice, ants, skunks are discouraged with only a few inches. I put most of our bees on pallets. They give some air circulation, help keep weeds out a bit and give this idea a start. A few are on big upended concrete blocks with a big concrete tile. That’s a great answer but expensive. I like to spread wood chips around to help keep down weeds.
Strong hives more easily resolve disease issues. Beekeeper can boost the populations with brood and bees from supportive nucleus colonies. Besides helping solve health issues, it’s easier to raise large queen cells and gather large honey crops.
Swarming is a good thing. It interrupts the brood cycle of varroa as well as the bees. This forces varroa to be among the bees of the hive. Bees with good hygienic traits can then clean house. The beekeeper can also intervene at this time to apply varroacides with greater impact. At Sky Barn Apiaries we use various biological varroa treaments like thymol, hopguard and oxalic acid.
Beekeepers are well served by making nucs to use for support colonies and for re-queening with desirable support nucs made with preferred breeding stock. Re-queening becomes a simple operation of removing an old queen and giving the hive brood and bees with a new queen.
The loss of genetic diversity in honeybees seems to be associated with poor health. There has been a significant reduction of diversity in the last decade. It seems prudent to continually add varieties of different stock to a beekeepers breeding strategy.
As I survey my winter losses and survivors I have learned a lot that is summed up in this article.
Many people at the Conference talked of their experience being part of an epidemic of queen loss that was high the last couple years. I had trouble with numerous queens last summer too. I wouldn’t be surprised if queen troubles go on into winter. And I believe it is much more involved than experiences with nosema ceranae.
It’s still early, but to date our bees have survived about 50%. They’re mostly good strong ones. Of the dead, most died while there was still very much honey. This indicates disease, and most likely varroa-carried viruses. I did not sample for varroa often enough and I’ve yet to take an after-treatment assessment sample. I think that should become routine.
A good number of my dead bees likely had nosema apis, which is not the same, but is often associated with dysentery feces on the combs. I’ve assumed the nosema that caused my summer deaths was n.ceranae, but I have now learned it can also kill hives in winter. So I’ve sent more samples to the Beltsville Bee Lab. The Beltsville reports usually include a few potentially fatal infestations that seem more deadly with synchronicity, the presence of varroa with nosema and chalkbrood, for example.
A few colonies died from starvation and the combs were empty. I think these were all struggling from getting emergency measures too late. I’m learning that bees begin building populations of winter bees in late summer/early fall, when the bees actually need to be in good health condition for the winter. It seems futile to put summer bees into winter with much less than a lab-type controlled environment, temp, light, and feed, like in a greenhouse. It might be easiest to take them to Florida, part of some success in days-gone-by, though also very stressful when my bees picked up American Foul Brood, the biggest, baddest contagious disease of bees.
There has been some robbing of the dead hives since we’ve had temps over 55. Robbing can be a vector of disease. It follows the demise of a hive that may have contagious pathogens. Robbing seldom happens under 50 on a fair, high pressure barometer day. Robbing doesn’t cause the demise around here. Perhaps with other species like Africans, there are incidents of extreme defensiveness, perhaps aggression, when they can rob a fairly strong colony to death. Those too are likely a stressed colony, diseased and too weak to provide enough guards. The problem with robbers is that disease organisms can be picked up and brought back to their colony.
Note: It is increasingly possible that African bees arrive in NY on trucks with a migratory operation, packages or nucleus colonies.
There is a lot to learn about the health of honeybees. It changes and continues with new pathogens arriving on the scene. Coming out of winter and assessing losses is a time of acute concern for the health of our bees.