Overwintering of Honey Bee Colonies
Overwintering of honey bee colonies
This subject has long generated endless debate among beekeepers. There are a few excellent resources by those who have collected hard data:
Dr. Floyd Moeller was a USDA researcher who performed extensive field research to test various beekeeping management practices.
This excellent publication covers practices to improve overwintering success, and although written in 1977, most of what he wrote is still relevant.
Updates would be:
- Nosema apis has now been largely replaced by N. ceranae, which doesn’t appear to cause as much problem over winter; his recommendation to prophylactically fed fumagillin is now questionable.
- We’ve now learned that prophylactic feeding of antibiotics against brood diseases results in the development of bacterial resistance. And sulfathiozole is no longer allowed in hives.
- There is debate as to upper ventilation of hives during winter. The issue centers on whether the benefit of the induced convection current outweighs the cost of the additional heating load placed upon the colony. In most areas, simply placing dry insulation at the top of the hive, with a winter wrap in windy areas, seems to be adequate. Moisture accumulation may be the result of the cluster size being out of balance with the cavity size (too small a cluster in too large a hive).
Read Moeller’s report at: Moeller 1978 Overwintering of Honey Bee Colonies
Two other articles of great interest were by Bernart Mobus (umlaut above the o), published in ABJ back in 1998.
Mobus 1998 brood rearing in winter cluster
Mobus 1998 winter cluster part 2
I’ve also covered the subject at:
The Physics of the Winter Cluster