Uniting Colonies

Uniting colonies means combining two honey bee colonies into a single, strong colony under one queen, without fighting. In most cases, uniting a weak or queenless colony is a better decision than taking it into winter on its own; the safest method is slow uniting with newspaper.

Why unite colonies?

In beekeeping, strength matters more than the number of colonies. A colony that goes into winter weak struggles to keep its cluster warm, uses its stores inefficiently and often comes out in spring either dead or too weak to be of use. Uniting two weak colonies turns the risk of losing both into one strong colony.

Uniting is not a failure but resource management: it is the way to use bees, stores and combs most efficiently.

When should colonies be united?

• Colonies going into winter weak: Colonies that barely cover a few frames in autumn are united with a strong colony or with each other.
• Queenless colony: If the queen has been lost and a frame of eggs or a new queen cannot be given (for example in autumn, when there are no drones left), uniting is the safest way out.
• Laying worker colony: This colony will not put itself right on its own, and it usually does not accept a new queen either.
• Failing queen: A queen that lays only drone eggs or produces very irregular brood can be removed and the colony united.
• Building strength before the flow: During the main nectar flow, two medium-strength colonies usually produce less honey than one strong colony. For this reason some beekeepers unite before the flow.
• Returning a swarm or split: Splits made to prevent swarming can be reunited with the parent colony during the flow.

When should you not unite?

A colony with a high varroa load should also be treated before uniting; otherwise the mites and the viruses they carry pass into the healthy colony. "Weak + weak = strong" is not always true: if both colonies are weak for the same reason (disease, a poor queen line), uniting only makes the problem bigger.

Choosing the queen to keep

When uniting, decide in advance which queen will stay and remove the other. If two queens are left together, one will die, but it is the colony, not the beekeeper, that decides which one survives.

• Age: A young queen is preferred; the marking colour makes it easier to know her age.
• Brood pattern: The queen that produces a compact, solid, even brood nest stays.
• Temperament: Choose the queen whose bees are calm and stay on the comb.
• Health: The queen of the colony that shows no disease or chalkbrood stays.

Uniting with the newspaper method: step by step

The newspaper method is the most common and safest way of uniting colonies. The bees meet gradually as they chew through the paper; during this time the colony odours mix and fighting is largely prevented.

1. Remove a queen: The day before uniting, or on the same day, find and remove the queen who will not stay.
2. Work in the late afternoon or evening: The foragers have returned to the hive and the risk of robbing is lower.
3. Open the colony whose queen will stay: Remove the crown board, leaving the tops of the frames exposed.
4. Lay a single sheet of newspaper: Lay one sheet of newspaper covering the whole box. Do not use glossy, coated paper; the bees cannot chew through it.
5. Make a few small holes: A few holes the size of a pencil tip give the bees a starting point. Large tears lead to fighting.
6. Put the other colony on top: Place the box of the colony that has been made queenless, with its frames, on top of the newspaper and close the hive.
7. Reduce the entrance: The united colony must be protected against robbing for a few days.
8. Wait: The bees usually unite within one or two days by chewing through the paper. Seeing shreds of paper in front of the entrance shows that it is working.

Uniting in single-box hives

In single-box hives, the frames of the two colonies can be placed with an empty box on top of the newspaper. A few days after uniting, the frames are gathered into a single box: brood in the middle, honey and pollen frames at the sides, and empty and old combs removed.

Other methods of uniting

• Direct uniting by masking odours: During a strong nectar flow or between hives standing very close together, bees can be united directly by mixing their odours with light syrup or smoke. It is risky during a dearth.
• Shaking out (for a laying worker colony): The bees of the laying worker colony are shaken onto the grass some distance from the hive. Bees that can fly disperse into neighbouring hives and are accepted; most of the laying workers cannot return. The empty hive is removed immediately.
• Uniting with a queen cage: Two queenless groups are united and a new queen is introduced in a cage. This serves both to unite and to requeen.

Hive position: bees return to the old site

Forager bees memorise the location of their hive. If you move a hive more than a few metres to unite it, a large proportion of the foragers return to the old site and, finding no hive there, drift off or are lost. To avoid this:

• Bring the hives to be united closer over a few days, half a metre to a metre each day; or
• Move the hive to another apiary more than a few kilometres away and unite it there; or
• Leave a small box at the old site and, in the evening, shake the bees that have gathered there into the united colony.

After uniting, placing an obstacle (a branch, a board) in front of the hive at its new position helps the bees learn the new location.

Checking after uniting

Leave the hive alone for a few days, then check it:

• Has the newspaper been chewed through? The bees carry the remnants out.
• Is there a pile of dead bees? Many dead bees in front of the entrance or on the floor are a sign of fighting; this usually comes from making too many holes in the newspaper or uniting during a dearth.
• Is the queen laying? Fresh eggs show that the queen has been accepted.
• Have queen cells been built? If queen cells are seen in the united colony, the queen's status should be checked.
• Arrangement: The brood should be gathered into a single block; surplus boxes and empty combs should be removed so that the colony is reduced to a volume it can keep warm.