I like to flutter about the web reading articles and various posts on bees. I pick up some interesting information (you need to be discriminating about the resource!) but often lose the source of information. But this time, when I stumbled upon a post talking about the same interesting tidbit I had read several years ago, I had to share!
This has to do with what bees do in winter. People often ask –do the bees hibernate? Do they freeze? Do they die? I tell them that honey bees are still moving and living during the winter. They cluster around their queen to keep her warm and maintain warm temperatures on brood (if it’s present). To keep any one bee from actually freezing, they take turns by rotating the outside bees inward and the inward bees to the outside of the cluster. Only the queen does not rotate. Of course this is extremely interesting. But the piece de resistance is when I inform them of studies that were completed where colonies were placed in subzero freezers with ambient temperatures of -20ºF and the cluster still maintained a balmy 70ºF and more! Found a reference to the same information:
Honeybees are neither freeze tolerant nor freeze avoiding. They die of hypothermia if their body temperatures are lowered to approximately 7 degrees C. In fact, they are endotherms. Like humans and other mammals, they control their body temperatures by producing internal heat, mainly by shivering their flight muscles. In addition, they huddle together into a large mass that conserves the heat produced by the individual bees. Individuals within the cluster move in and out between the center and the outside edge of the cluster. This combination of endothermy and clustering keeps their body temperatures well above freezing right through the winter. In one experiment, when the air temperature around the cluster was kept at 5 degrees C, bees at the center of the cluster had body temperatures of 35 degrees C and temperatures of individuals on the outside edge were approximately 19 degrees C. The center of the cluster generally stays between 30 and 35 degrees C even at outside temperatures as low as -30 degrees C.
From this excellent site: http://scienceblogs.com/lifelines/2011/07/19/cunning-cuttlefish/
I like that he spoke to someone who specializes in antifreeze properties in insects.