My husband and I got our first hive last spring.  The hive
          produced honey and grew in population.  Early winter we put
          the hive into a building because it gets very cold in winter
          in Iowa.  The building was not heated, but served as a wind
          break.  The hive had plenty of food and we also gave
          supplemental food.  My husband looked inside recently, and
          he said they all looked dead.  None were moving around.
          Are they dead?  Do they sleep all winter?  Any ideas of why
          they died?  The hive was brand new, so disease (we hoped)
          would be kept at a minimum.  Thanks for your help.
 
          Mary