A colony declines after harvest: four causes and how to recover it

The colony was strong, you took one harvest, and now numbers are thinning and the nest is not expanding. This is common in a first year, and four causes account for nearly all cases.

1. Too many honey pots taken

The most frequent cause. The colony has lost its reserve, so it must forage harder, numbers fall and the brood contracts. Prevention: always leave at least a third of the honey pots. Recovery: no further harvest for at least six months, and supplementary feeding if it is the dry season.

2. The brood was damaged

Piercing the wrong pot or breaking part of the brood mass. The colony loses that cohort of larvae and needs months to make it up. Prevention: identify the three zones clearly before touching anything.

3. The box was open too long, or opened at midday

Internal temperature spikes, wax softens, the colony is shocked. Some abscond within days. Prevention: harvest in the early morning and finish in about fifteen minutes.

4. Ants moved in afterwards

Honey spilled on the outside of the box is a signal to ants, and a colony that has just been disturbed guards its entrance less well. Prevention: wipe the box clean immediately after harvesting and check the ant-defence cups that same week.

Recovering a declining colony

• Stop all intervention. Do not open the box for at least four weeks.
• Redo the ant defence and check the shade.
• If it is the dry season with little flowering, offer light sugar water outside the box, stopping when flowering returns.
• Observe the entrance weekly rather than opening the lid.

A colony that still has brood and a queen usually recovers over one wet season. A queenless colony generally needs to be merged with another.

Frequently asked

How do I know it still has a queen?

The most reliable indirect sign is fresh brood layers appearing and larval cells expanding. Do not search for the queen — opening up to look does more damage than the answer is worth.

Does feeding sugar water adulterate the honey?

It can if fed close to harvest. Stop feeding at least two months before harvesting, and never feed colonies whose honey is sold.

Should a weak colony be merged into a strong one?

If it is very weak and queenless, yes. If it still has brood and a queen, let it recover on its own.