As we pass through these last crazy days of yo-yoing temperatures, I have been taking advantage of the warm days to assess my beehives. I love being back with the bees. And it is wonderful to find that this year I beat the odds. My honey bees had a great winter. Of my twenty hives, my two smallest going into winter are struggling, and may yet fail. However, the rest of the hives look good and are building. With many healthy hives this spring, my mind is definitely on swarm prevention. May is swarm season in Michigan. Swarming is a honey bee colony’s natural way to reproduce. As honey bee colonies enter their spring growth phase, pollen and nectar become available and the colony fills with bees, the strongest colonies will try to reproduce by “throwing a swarm”. If this happens, the old queen and about half the bees in the colony will leave and look for a new home. They will leave behind at least one, and often many, unhatched new queens. If all goes well for the original (parent) hive, one of those queens will hatch, fly to mate and return to become the queen in the parent hive. If that fails, the parent hive will die out. When a swarm leaves a hive, the first thing it does is regroup some where near the hive for a few hours to a few days, while scout bees look for a new home. If I find the swarm during that time, and they are not too high to be reached, I can collect them and move them into a new hive. If I miss them, they will pick out their own new home and move on. To a beekeeper, a swarm that gets away is lost bees, and ultimately less honey. In additions, those bees have the potential to take up residence where they are not wanted (for example inside chimneys, soffits or walls). Therefore, my goal this time of year is to recognize when a colony is preparing to swarm, and discourage them from doing so.
Since crowding is a signal for bees to swarm, one of the things I am looking for when I visit the hives is how much space the colony has to grow. Does the queen still have room to lay her eggs? Do the worker bees have space to store pollen and honey? If not, I can try to discourage swarming by adding another hive box, in order give them more room to expand. I added boxes to a few hives this past week. I am also looking for the presence of drone brood. Brood is what we call all the young bees that are being raised in the cells of the comb. When a colony of bees begins their spring expansion, they start by raising only worker bees, but as the colony gets stronger, and their minds turn to reproduction, they will also begin to raise male bees, known as drones. Drones are bigger than worker bees, so as the young bees are sealed in to their cells for the metamorphosis from larva to bee, the drones look very different. The capped (sealed) worker brood is flat, while the drone brood sticks up above the comb, with a domed top.
Colonies will not swarm until there are drones available to mate with any new queens, as successful mating of the queen is vital to the survival of the parent colony. This week, many of my colonies had their first drone cells. The appearance of drone brood tells me that swarm season is approaching and I had better be ready to intervene.
Finally, in preparation to swarm, the colony will begin to raise a new queen. To do this, the worker bees begin by creating special cells for queens to grow in. Called queen cups, these cells are unique as they face downward. The eggs laid into the queen cups are identical to those laid for worker bees, but because their diet consists of a product from the worker bee hypopharyngeal gland, called royal jelly, the larva hatched from those eggs develop into queens. Royal jelly, also sometimes called bee milk, is fed to all the young bee larva, but only those destined to be queens receive it beyond their first few days of life. As the queen larva grow, the worker bees extend the queen cup into a structure known as a queen cell, which looks sort of like a peanut. Although there are other reasons why a colony might raise a new queen, in the spring, the desire to swarm is by far the most common. Queen cells produced for swarming are usually found along the bottom of the honey comb, and are also called swarm cells. I did not see swarm cells this past week, and hope to have two or three weeks before they begin to appear.
Once a colony starts raising swarm cells, they are determined to reproduce, and the only way to discourage a swarm is to split the hive, and let the parent hive raise a new queen. With a split, I am basically simulating a swarm by moving the old queen and a portion of the colony into a new hive box. In the window of time between the appearance of drone brood, and the appearance of swarm cells, I have the opportunity to intervene and redirect the bees from swarming with my own “suggestions” for the hives. This year I will be importing a few non-local queens because they have been bred for genetic resistance to a bee pathogen known as Varroa Destructor. As the name implies, the mites can be devastating for bee colonies. Ideally, before swarm season kicks in, I will use mite resistant queens to replace queens in those hives that struggled to control mites without my help last year. My goal is to improve my hives’ ability to handle the mites by incorporating more mite resistant genetics into my bees. In addition, over the next few weeks, hopefully before the bees begin preparing to swarm, I will makes splits on those colonies that have characteristics I want to increase in my hives, such as calm, gentle bees, good honey production and good mite management. That way, I am encouraging reproduction of the bees most valuable to my apiary, without risking loss of that reproductive effort to lost swarms. Bee work is optimally done when the temperatures are above 60 degrees, so I must wait another week or so to start, as it is predicted to be cool again until next week. But after that, things will start to get busy in the bee yard, or as one of my beekeeping friends said this week “Game on!”