Autopsy of a Dead-Out
Why Did My Bees Die?
It's an all-too-common question every spring. Many beekeepers, both novice and experienced walk out to the bee yard to see how many of their colonies made it through the rough winter. There are a litany of reasons why a hive doesn't survive. We could talk about colony collapse disorder and other zebras that fly down from the center of the universe to destroy all of our hard work; but a better use of time and brain power should be spent on a more common culprit: Us.
Winter losses are common. Too common. The Bee Informed Partnership reports on annual losses each year. This data is, of course, only worth anything if we as beekeepers submit our numbers to them annually. That being said; 2017-2018 was a hard season for many beekeepers. Across the country, BIP reports an average 40% annual loss of our colonies. This includes the backyard hobbyist and the commercial beekeeper alike. In my home state of Virginia, the data showed a 65% loss, with numbers probably higher at the hobbyist level due to suspected low reporters. The heavy majority of these losses were reported in the winter.
When I get calls about dead-outs. I start by asking "why do you think the hive is dead?" The more common answers I get are:
"I opened my hive and all my bees are in a pile on the bottom board"
-Yup, that colony is dead
"There are a ton of dead bees on the landing board and ground in front of the hive"
- That one may actually be a good sign. How would the bees get out to the landing board? They were probably carried out by other bees. Housecleaning is a common chore to be done during winter when the cold weather breaks. If you have bees on your landing board, especially ones without pollen on their hind legs, this is probably just hygienic behavior of the colony trying to clean out the ones that didn't make it.
"I don't hear anything inside"
-Again, not a guarantee. hearing bees through the walls of the hive gives us comfort that the girls are still alive in there, however it is also a sign of high metabolism. Quiet bees are actually a good thing. Russian bees are known to be quiet during winter. This combined with the fact that the Russian bees go through winter with a smaller cluster can sometimes trick the beekeeper in thinking there is no bees inside, when in fact they are very efficient and doing just fine.
So once we are sure the colony is died, it is time to start the autopsy. Before even visiting the yard, I usually ask three questions that may lend themselves to finding out what may have lead to the colony's demise:
1. What were your mite counts going into winter?