This time of year you wonder why or if you are a beekeeper. Winter losses make you question each. I share my results (both good and bad) in hopes we will all learn valuable lessons.
Since the end of January I have had additional losses, but analyzing the data may have pointed me to the biggest cause of my high losses. Remember that before varroa, winters losses typically ran at 15-25%. At this point my losses have risen to 45% (55% survival). Hopefully none of the survivors will dwindle away and via splits I can restock. From the beekeeper’s grapevine I hear other beekeepers are seeing from 0 to 100% survival. Most are in the less than 50% survival category.
My results in detail:
-Overall survival: 54.5%.
-Russian survival is at 56%. Italian survival is at 50%. Italians received a full MAQS miticide treatment. The Russians were either untreated or received a 50% MAQS dose. The survival rate for the treated and untreated Russians was the same.
-Wrapped vs unwrapped hives-same survival rates.
-Fall fed hives have an overall 68% survival. Un-fed hives have 32% survival rate.
-An unscientific (sample of one) observation: My one hive stocked with a feral swarm seems to be the strongest. (I had lifted the inner covers on all hives to insert brood builder patties)
a) Fall feeding is a definite boost to survival. In my data it is a bigger factor than queen type.
b) Russians are doing better than Italians even though partially or untreated with miticides. (Remember I am partial to Russians, so take this as you like)
c) Wrapping provided no measurable advantage for 2 years running.
d) Unscientific observation from the grapevine: Those beekeepers using miticides seem to have better survival than those who don’t use miticides. Using miticides is definitely a good short term strategy, but may not be the best long term strategy.
The difference in survival of fed versus unfed hives obviously had me intrigued. I queried two beekeepers with 100% survival. They all fall fed. In fact they were feeding twice as much sugar as I had used. They were feeding at a rate of 50 pounds per hive. I had fed roughly 25 pounds per hive. In addition the beekeepers with 100% survival had left a super of honey/sugar syrup on top of the brood chambers. The additional super provides more easily accessible food.
My next step will be to analyze each deadout during March to determine the cause of each hive’s demise; starvation, Varroa/DWV, Nosema, etc.
At this time I will probably be changing three things next year in my winter preparations.
1) Double the amount of fall feed I provide.
2) On a limited basis I will try the University of Minnesota recommendation of wintering with 3 brood chambers. In this scheme the beekeeper takes the normally untouched outer frames of honey from the two lower brood chambers and re-installs them in a third brood chamber above the cluster. During winter the bees always move vertically following the food while staying close to the warmth of the cluster. They usually don’t move horizontally until bumping into the inner cover. The 3 brood chamber scheme works with the bee’s natural tendencies and allows utilization of the unused honey from the exterior frames.
3) Continue with my changeover to Russian stock.
SEE YOU AT THE CLUB MEETING AT THE RIPON PUBLIC LIBRARY ON MARCH 12th. I AM SURE WE WILL BE DISCUSSING WINTER SURVIVAL.