In everyday English, to “backfill” means to refill. So if you want to plant a bush, bury a conduit, or repair a water main, you dig a hole, do what you have to do, and then put the dirt back in. Simple enough. The meaning is only slightly different in beekeeping, but different enough to be confusing.
In beekeeping, backfilling refers to filling an empty brood cell with honey or sometimes pollen. In other words, a cell that previously held one or more generations of developing bees, is now used to store food.
This may occur at different times of year. For example, in the fall when the colony has finished drone rearing, the drone cells may be filled with honey. There are several good reasons for this: drones won’t be raised again for many months, the cells are the wrong size for workers and, since they are close to the main nest, they are convenient storage areas. A well-stocked pantry right at your finger tips—er—tarsal claws!
But there is another time when bees start backfilling . . . just before swarm season. But first, let’s back up a few weeks.
In the early spring the brood nest expands in a process that is the opposite of backfilling. As the bees use up the nectar and pollen adjacent to the brood nest, they turn those empty cells into brood-rearing cells. This allows the colony to raise many more bees—enough bees to maintain the hive and prepare for winter, as well as enough bees to swarm.
Then, as swarming time gets close, the bees begin backfilling the outermost brood cells with honey. This shrinks the nest size, which in turn decreases egg laying by the queen. It means that, after the swarm leaves, the brood nest will be small enough that the remaining bees will be able to care for it. Backfilling provides a way of scaling down the entire operation so a greatly reduced workforce can still get the job done. Ingenious!
It is important to understand the concept of backfilling if want to manage swarms. Checkerboarding—a popular but often misunderstood swarm management technique—is based on this backfilling behavior. Checkerboarding should be started at the peak of brood nest expansion, just when the nest stops getting larger and begins to shrink . . . but more on that later.
Just for the record, “backfill” can also be a noun, the name for the stuff you put in the hole, as in “They already capped the backfill.”
Rusty
HoneyBeeSuite
Backfilling a hole with dirt. Flickr photo by Archaeobobalist.
Checker boarding works wonderfully for putting off the swarming instinct and building a large population for the nectar flow.
Rusty…Can’t wait to read your post. Would you write a post on using the checker boarding method?
Herb,
That’s the plan. First some theory, then the how-to.
From what I’ve read, the queen’s laying also drops off before swarming because she is being fed less and chased around the hive by the workers to get her into flying-fit condition. So could filling more cells with honey be a result of more cells being egg-free rather than a deliberate attempt to shrink the brood nest before swarming?
It doesn’t really matter why they end up doing it as the outcome is the same, but I would love to know how conscious the bees are of their behaviour and its future effects, whether they are on automatic pilot or have some sense of how they are contributing to the future of the colony. Bit of a rambling comment sorry!
Emily,
We will probably never know since we can’t think bee. But I think the activities are related with the workers doing the backfilling and the chasing more or less simultaneously, although some sources say the backfilling may begin up to two weeks before final swarm preparations begin. Once final prep begins, which includes slimming the queen, it is virtually impossible to stop a swarm without significant interference with the colony. One thing that is certain is that the workers call the shots, not the queen.
Thanks Rusty
Can you discuss the Demaree method in the future as well as a swarm prevention method prior to colony swarming once open cells have been dsicovered.
I have read about it yet still not totally certain.
Hey Jeff, glad to hear from you. Just yesterday I was wondering where you’d gone.
Anyway, sure, I’ll do a piece on the Demaree method as soon as I finish up with checkerboarding.