Hibernating Bumble Bee

Recently we have had the first frosts of the winter and insects have more or less disappeared.  On my Saturday afternoon walk I turned over a log in the Wilderness and found this hibernating bumble bee, Bombus sp (Hymenoptera: Apidae).  It didn't move and, after photographing it, I carefully covered it up again without disturbing it.  Only when I got back home and looked at the photos did I notice the mites, which the photos show were moving about.

See here for a bumble bee from back in 2010, also covered in mites, that has probably just emerged from hibernation.

Photo taken in the Wilderness, Whiteknights Park, Reading University grounds, Reading, UK, on 2011-12-10.