The warm Saturday (40°F/5°C) should have seen cleansing flights but there were none. Out we went to thump the hives with rubber mallet in hopes of rousting a guard bee or two or, at least, raising a buzz audible through our stethoscope. No joy at all.
Removing the roof from Beatrix exposed some mouse nesting material atop the eke, which itself was intact. Lifting the eke and opening the hive we found combs of plentiful honey and, as expected, dead bees, most on the floor and a lesser number in cluster. There was also a snugly nested live mouse, which we evicted. At least there was no sign of damp.
Disheartened and learning nothing useful from our comb-by-comb inspection we gave Clarissa and Dorcas the most cursory of examinations merely to establish that they were mouse-free and turned to Dr. Meghan Milbrath for professional help in conducting the post mortem on the other two hives. While she rightly warned us that it could be difficult to come to a specific conclusion for the reasons for a deadout, we were rightly certain that she could point out things we had missed and their significance.
The following Tuesday we opened Clarissa and Dr. Milbrath worked her way through the hive from the follower board towards the brood nest. The combs began with a good number full of honey. Then a few less full and with some uncured honey. Finally in the brood nest, a small cluster around the original marked queen at the top of the comb. And eggs! Also a small bit of bee feces. But her most critical observation was how many of the odd flecks of detritus on the floor were dead varroa. Dorcas showed a similar pattern with an even larger brood chamber. We had certainly been lulled into false security by the lore that says first-year colonies need not worry about varroa. While often true any colony with a lot of brood is vulnerable, even a first-year if it grows to strength quickly.
The scenario proposed by Dr. Milbrath as likely is that the varroa weakened and killed many of the winter bees, those produced at the end of summer. That alone could have doomed our colonies but the warm spell we had made things worse by prompting the queen to lay eggs. When the temperature again dropped the diminished colony could not re-enter cluster as it fecklessly tried to keep the new brood warm and was further diminished. In addition the uncured honey may have fermented and sickened any consumers. Finally the tendency to climb rather than move to another comb for food would work against such a small colony even if it were not stuck trying to protect brood.
To prevent a recurrence with the nucs we have ordered for this year our plan is:
Some of these are leading us away from our inclination to let the bees manage on their own as they see fit but that has not been working out well for them.
2015 January 23
Beginning Another Year BeelessPosted by theprospectofbees under Uncategorized | Tags: beekeeping, deadout, Dr. Meghan Milbrath, mouse, varroa |