Nucs and how to use them effectively

Why ‘nucs’ are important in beekeeping

There are many uses for nucs in several beekeeping management situations. Some examples of their use are to:

  1. overwinter spare queens and bees to make up for winter losses
  2. as part of artificial swarm management
  3. introducing bought in queens
  4. make increase from a colony with queen cells

This article aims to provide detail on the type of nucs that are available, how to make up nucs and situations when they are can be part of beekeeping management.

An important point to bear in mind for all nucs is that they will require feeding otherwise they will struggle to thrive. There are various tray feeders available which are fairly cheap and are easy to fill and use. So nucs must be inspected regularly to ensure they have enough food. Pollen isn’t normally an issue as there normally enough bees to forage for their protein.

First the type of nucs. They can be wooden or made from polystyrene. Equipment manufacturers provide wooden nucs which generally hold five or six National frames but they can be quite expensive. Someone with basic carpentry skills can make a 5/6 frame nuc from timber offcuts which are just as good as those professionally made. The important point to remember when making them is to ensure bee space measurements are taken into account. If the nuc is to overwinter as a colony then the thickness of the wood should be at least 12mm to retain heat in the cold months. If they are to be used for the summer only then thinner wood is acceptable.

Another option is to modify a National brood box by placing a thin piece of ply down the centre of the box, make up two separate crown boards to cover each section and screwing a floor to the brood box. It is important that each section is bee tight otherwise bees will mingle between the two halves which must be avoided. This type of nuc is suitable to overwinter as each colony helps to keep the other warm.

Polynucs are very good at overwintering colonies as they retain heat very effectively. Some types have a well so that bees can easily be fed; other types require a frame feeder to feed the bees. Generally, polynucs take 6 National frames which allows for a reasonable size colony in springtime. The downside of polynucs is that they cannot be cleaned using a heat gun or similar whereas wooden hives are fine to do so. However, they can be cleaned with hot water and soda crystals which is very effective at removing propolis and dirt.

If a 6 frame colony is transferred to a National brood box in early spring, it can grow to a full colony within a few weeks and will produce a crop in that season. It is advisable to feed the bees with syrup when they are transferred along with the addition of drawn comb if available. Bees are reluctant to draw out comb early in the season so drawn comb from the previous year should be stored carefully overwinter, i.e. away from rodents and wax moth.

Polynucs are also available to split into two sections, thereby making two 3 frames nucs from a single box, each with their own entrance.

So there are many ways that a small container can be constructed or adapted to enable bees to overwinter.

Making up nucs.
A point to bear in mind when making up a nuc is where it will be located once stocked with bees. If in the same apiary then many bees will return to the home colony. However, if it is moved away to another apiary that is at least a couple of miles away then not so many bees are needed. Yes the three mile rule can be bent a little here as not too many foragers will find their way back to the original site as long there is forage at or near the new site.

If the intention is to make a queenless nuc then It is important that the queen is located in the main colony and caged whilst the nuc is made up. Generally, it is a good idea to take a frame of sealed brood with attendant bees from the parent colony and place in the nuc. Then add a frame of stores with bees followed by frames of empty drawn comb and or foundation. Now shake bees off frames from the parent colony into the nuc. It is better to add nurse bees to a nuc so, before shaking bees into the nuc, give the frame a medium shake. This causes mostly flyers to drop off the frame leaving nurse bees hanging on. Now shake the frame very firmly into the nuc which will dislodge the nurse bees. Do this with up to three frames from the parent colony, then close the nuc up and place it in a shady area of the apiary. The number of bees needed will depend whether it is to be placed in the parent apiary or located elsewhere.

Another consideration is the time within the season that a nuc is made up. From mid July onwards robbing by wasps or other bees can be an issue, so make the entrance small and easily defendable. Placing wasp traps nearby the apiary will help reduce this problem.

Uses for nucs.
1) Introducing a bought in queen.
Introducing queens is a topic fraught with difficulties as bees sometimes kill the queen, which is costly. The best chance of success if to have a nuc with young bees. This is where siting the nuc is relevant as if placed in the home apiary the flyers (and they are generally more aggressive) will return to the parent colony leaving behind nurse bees. Leave the nuc queenless for 24 hours after making up as they are more receptive to receiving a queen. Suspend the cage with the queen between top bars in the centre of the nuc and leave her in the cage for a further 24 hours. Now snap off the tab on the cage preventing bees access to the fondant. The nurse bees will then eat the fondant and release the queen in due course. Leave the nuc well alone for 10 to 14 days and then check for the presence of brood. When the nuc starts to build up it can be transferred to a full box if that is the intention or over wintered in the nuc box.

2)  Make increase with a queen cell.
Here it is not necessary to have mainly nurse bees so the nuc can be sited in another apiary. Again, leave it queenless for 24 hours after it is made up. Queen cells can be harvested from a colony with swarm cells, cut generously from the frame so as not to damage the queen cell. Place the cell between top bars in the centre of the nuc leaving the queen cell hanging vertically. It is better to take cells that are mature, denoted by a darkening at the tip of the cell. These cells have a well developed queen inside and there is less chance of damage to her when handling the cell.

There are various types of kit (Jenter for example) or techniques (Miller method) to force a colony to produce multiple queen cells from a queenless colony. The sealed queen cells from this approach can be cut out and added to a nuc as above. The queens emerge in due course, go on mating flights and then come into lay fairly quickly. This is a good way to produce queens from a stock with desirable traits. If the Jenter or Miller method is employed the number of successful queen cells can be established after a few days and this determines how many nucs will be needed. They can then be made up a day or two before the queens are due to emerge according to the records kept as part of the queen raising process.

3) Part of artificial swarm process
The descriptions for artificial swarming mention using another brood box to split the colony in half. However, a nuc can be used to house the queen along with a couple of frames of sealed brood, stores and empty frames. Ensure no queen cells remain on the frames that are transferred to the nuc. Move the nuc to a different spot in the apiary or another apiary, adding extra nurse bees if the nuc is to remain in the parent apiary.
In the parent colony this leaves most of the brood along with nurse and flying bees. And most importantly queen cells. It is now necessary to go through the brood box and inspect each frame for queen cells. Shaking a frame with queen cells can damage the developing queen so do not shake the frame with a queen cell that you wish to use. Place a drawing pin in this frame so that it can be identified during subsequent inspections. The aim here is to leave the colony with one sealed queen cell or two at most. If bees are left with one queen cell the queen may die in the cell for a variety of reasons. Leaving two cells is an insurance but could cause the bees to swarm if both queens emerge. In order to reduce this risk select queen cells that are very close to each other on the frame. When the first queen emerges it is easy for her find the other queen cell and allow her to kill the occupant.
Once a frame is selected and placed in the nuc the remaining frames must be inspected individually; knock down all queen cells (open and sealed) and now shake each frame firmly. It is now much easier to spot other queen cells that were covered by the adult bees. It is good policy to return to this box a few days later and shake all bees from the frames but not the one with the drawing pin. The bees may have produced more queen cells from very young larvae – sometimes bees do this and other times they don’t. So to avoid losing a swarm this second inspection is important.

4) Make increase from a colony with swarm queen cells
When a good tempered productive colony makes queen cells it is a good opportunity to make several nucs from it. Locate the queen if still present and cage her. If there are enough queen cells on multiple frames up to four nucs can be made up. Place two frames from the parent colony in each nuc, one of which has a well developed queen cell. It is not necessary to knock down spare queen cells as these nucs are unlikely to swarm if more than one queen emerges. Add additional frames of drawn comb and or foundation.

Now, move the parent hive to another location in the apiary and place the four nucs in a circle around the location of the original hive, all pointing inwards to the parent’s hive original spot. Flying bees will return to this location and normally populate the nucs in a fairly even way.

The queen is returned to the parent hive and extra frames added to make up for the eight that were placed in the nucs. Add the supers on top of the colony containing the queen. This colony will now build up again and will be able to overwinter if that is the intention.

5) Housing swarms
Beekeepers are often called upon to collect swarms and nucs are an ideal home for them for a short time. As a nuc is small in size they are easy to transport if necessary. It is good practice to have a separate apiary for swarms so they can be checked for disease and temper before moving them to main apiaries. When they have been checked it is easy to move them elsewhere in order to transfer them to a full box.

Wally Thrale