It wasn't the polar vortex or lack of insulation that did this hive in. The colony was dead before the cold weather even presented a problem. When last inspected, this colony was robust and actively bringing in nectar. I suspect warm weather through October may have contributed*, or perhaps the cause was varroa. What do you think?
Some background on this colony. The hive was stocked with a package of Carniolans in April 2013. It had the benefit of a full set of drawn combs and honey stores (long story there) so all they had to do was build up. It overwintered fine, and Marty let me know that the box was "full of bees" in late June. It was filling with honey, too. We harvested in July, August, and September (just two combs each visit). Labor Day weekend, I think the colony was occupying about 15 combs and had 4 full combs as Winter stores. One might think that's not enough honey, but the flow was still good in September and Carnies are pretty conservative.
Normally, I button up my hives by Halloween but I'm learning that keeping a hive in an outyard redefines what's normal, and we neglected the hive for the remainder of September and the entire month of October. When we finally visited post-Thanksgiving, we found the empty hive. No pile of bees in front so definitely not pesticide poisoning. No big pile of bees inside the hive either. No pile of shredded wax so definitely not robbing.
So, what do you think?
No #bees. Is the cause varroa? http:/bit.ly//1A222R0 pic.twitter.com/g1RzbIc4Dl
— HB (@Hello_Kitty_) November 29, 2014