This article is intended to provoke comments. Please send in your thoughts if you think you
see something we didn’t.
Gerard took some pictures of a neighbor’s hive which died
this past winter. The owner said all
appeared to be going well until mid-December, when the hive suddenly died. Also the beekeeper did NOT use any miticide. The
hive had already been partially cleaned up prior to Gerard seeing it. Gerard then shared the pictures with two other beekeepers and together they
tried to deduce what happened to the hive.
This first picture shows randomly distributed capped drone
brood.
The second picture shows some bees head first into empty
cells. (Remember the hive had been
partially cleaned up. There may have
been many more bees in this condition.)
This close-up also shows what may be varroa poop (excrement) near the
mouth of some cells. See the little white gobs on the cells walls.
Using these limited clues our trio of beekeepers have
attempted to deduce what may have happened.
Here is what they have postulated.
1)
The randomly capped drone brood in the middle of
the frame is usually a sign of laying workers. Laying worked usually emerge only after a few
weeks of being queenless.
2)
Then take into account the drone brood takes 3 1/2 weeks to mature and emerge. This means
the hive was likely to have been queenless for a period of at least 6 weeks.
3)
The loss of the queen would of itself cause the
hive population to dwindle and die out during the winter.
4)
A second possibility is that it could also have
been a sick queen which began laying drones only and in a random pattern, but
this considered less likely.
5)
The "head first bees in cells" is not considered
overly significant. When the bees are in
cluster this is the position of many of the bees when they are in tight
cluster. They occupy the cells in order to
maximize the bee density to conserve heat.
6)
The presence of the varroa poop is not
surprising. All hives have varroa mites
in them. We also know deformed wing virus (DWV) is
carried by varroa. The sigificance here is that the cell cleaner bees have not removed it. Unfortunately the
hive was cleaned prior to Gerard seeing it, so he could not look for K-wing or
short abdomen worker bees which are characteristic of DWV.
Our 3 man team is divided between
queenlessness and varroa/DWV as the root cause of the hive’s death.
So what do you think killed this
hive? Please post your thoughts in the
comments section.
Another interesting
observation. This beekeeper lost 2 of
3 hives. The living hive is next to a
planting of hops. There was some
speculation the hops may have been controlling the varroa. If you are not aware, Hopguard miticide is derived from hops. Discounting this theory is the fact that one of the deceased hives is located only 200 yards away. It also should have received the benefit of the hops.
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