Mary Westendorf queries: "Are they dead?"
 
It's hard to call the hive as she described it (dead or not).  The usual
cause of winter loss is starvation.  Her description said there were
plenty of winter stores.  Also, starvation usually takes its toll on a
hive in the early spring, not in the height of winter.  Stores should be
sufficient to make it through a winter and the loss due to starvation
most often takes place when brood rearing commences in the early spring,
before the bees are able to bring in sufficient nutrients to maintain
the new brood.  It is at this time that supplemental feeding is most
important.
 
A description of the usual winter activity of a hive may help.  In the
winter the bees are less active, but they do not sleep all winter.  At
temperatures below 45 degrees F, the bees form a tightly packed cluster.
This cluster spends the cool/cold days and nights vibrating to generate
heat to survive.  The friction from wagging bodies and buzzing wings
generates enough heat to keep the bees warm enough to survive.  At
the center of the cluster is the queen.  The bees on the outside of the
cluster work their way to the center and the center bees take their turn
on the outside.  The fuel for the cluster is honey.  The cluster will
work its way around the frames containing winter stores and eat and buzz
its way through the winter.  The main cause of starvation in the winter
is overharvesting in the fall.
 
On days when the temperature climbs to or above 45 degrees F, the bees
will fly from the hive for cleansing flights.  On these days the bees
are able to void themselves, something they will not do in the hive.
On such days the snow around my hives is very polka dotted with bee
excrement, which explains why you should never ever locate your hives
near a neighbor's clothes line!  Thus, winter loss can be caused by too
long a stretch of cold weather when the bees are unable to take
cleansing flights (perhaps more likely in Iowa then starvation).  When
overwintering in a building, one must accommodate the bees biological
needs.  Access from the building to the great outdoors must be given,
the building must not get too warm on cold days (the bees will leave to
take their cleansing flights only to freeze when exposed to the cold
outside temperatures) and the interior of the building must also warm up
on warm days, so the bees realize that they can take cleansing flights.
If the building is located in the shade and remains cold on warm days,
the bees will never get a chance to void.  Another thing to keep in mind
is how bees orient themselves with regard to their hive.  The 'under
three feet/over three miles' rule of thumb needs to be taken into
account.  All in all, this over wintering inside a building is a tricky
thing and although I have never tried it personally, from what I have
read about it, I don't reccommend it.  My hives are located in upstate
New York (growing zone 3) and I wouldn't dream of going to the bother.
Wrapping the hives for winter protection is as far as I would go, and
for the past five years I haven't even done that, and have had no
winter losses.  Feral bees have survived for years without any special
care or human intervention.
 
Finally, a word about opening a hive in winter.  It is not necessary.
One can determine the state of a hive simply by putting an ear to the
side of a hive and listening.  You will be able to hear the hum of the
winter cluster.  Quantity of winter stores can be judged through the
weight of the hive simply by tipping the hive.  If one discoveres in the
middle of the winter that their bees don't have enough stores to make it
through the winter, there is nothing they can do at that point to help
them out anyway.  If the bees make it through the winter, be ready to feed
them in the early spring.  There is no need or reason to be poking
around a hive in the middle of the winter.  Go skiing instead!   ;-)