Swarm prevention

Why they leave

Swarming is reproduction at the colony level. A colony that has built up well, run out of room and has a queen whose pheromone no longer reaches every bee decides to divide itself. The old queen leaves with roughly half the workers and the colony raises a new one.

Nothing about it is a fault. It is what success looks like if nobody intervenes.

The window

Penn State puts the peak at mid-April to mid-June in the mid-Atlantic, during spring build-up. Your own window moves with your spring. That is the period when everything matters and the rest of the year it barely does.

What to look for

• Queen cups on the bottom edges of frames, and whether they have eggs in them. Empty cups are normal, charged cups are a decision in progress.
• A brood nest with nowhere to go, wall to wall with no empty comb.
• Bees bearding heavily in weather that does not explain it.
• A colony that has stopped bringing in nectar while everything nearby is flowing.

What actually works

Give them room before they need it. Add a super while the colony is still building rather than when it is full, because by the time it is full the decision has often been made.

Open the brood nest by moving frames so there is empty comb for the queen to lay in. A brood nest with no room reads to the colony as a reason to leave.

And take the pressure off by making a split before they do it for you. A planned split is the same outcome with you choosing the timing and keeping both halves.

If they have already started

Once queen cells are charged and capped, prevention is over. Penn State is clear that the most effective response at that point is to split the colony: separate it into two, one half with the queen and the other with one or more queen cells.

You do not get to talk them out of it. You get to decide whether the division happens in your apiary or in somebody's tree.

References