Spotting starvation, and emergency feeding in the cold

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Autumn feeding: about 20 kg, and how to get there is about getting the stores in. This page is about the months afterwards, when the stores only go down. The awkward part is that a colony can starve with food a few inches away, and the check most people rely on will not show it. Bees can starve at any time of year, but winter and spring are when it usually happens.

Hefting, and what it tells you

Hefting means tilting the hive and lifting each side in turn, one at a time, to feel the weight in your hand. Lift both sides. Stores are often not spread evenly across a box, and a heavy side can sit next to an empty one. 3 Every other week through winter is the interval the NBU gives.

It is most useful when the weather is cold, and it takes practice. What tells you the hive is heavy enough is your own memory of the same hive last month. 1

So heft everything once in late autumn, when the feeding is finished and the weight is right. That is your baseline. Be careful doing it. A hive can be heavier than you expect, so lift properly and get help if you need it. The last look before winter is where that baseline gets written down.

Isolation starvation

This is the one that catches people out. The cluster works its way to one end of the brood box and eats what is there. Then it cannot cross the cold gap to the rest. In a tight winter cluster, remote from the stores, bees starve very quickly. 3

A mild spell makes it worse rather than better. The cluster breaks up, the temperature drops again, and it re-forms somewhere that is not where the honey is.

Hefting will not show you any of this, because the weight never left the box. The NBU says so plainly, and asks for a quick look inside as well. 1 A hive that felt reassuring in December is exactly the sort that is found dead in February. If you are already looking at one, working out what happened is worth doing before you clean anything up.

Set ivy honey, the other heavy hive

Ivy is a real late source in much of the UK, and ivy honey sets very hard. To eat set honey the bees need water to soften it. If the weather keeps them in, they cannot go and get any, and a colony can die with large heavy stores of set ivy honey still in the frames. 1

There is a way to head this off, and it happens in the autumn rather than now. Feed syrup while the bees are still bringing ivy nectar in. The syrup goes into the comb mixed with the nectar, which helps stop it setting into a solid mass.

Water matters all winter for the same reason. Bees need it to use fondant and set stores, and often they take it from condensation inside the hive. 2 More on that in Water for bees.

Looking inside in winter

Pick the day. As warm and sunny as you can get, and ideally with a few bees flying, because that means they are not in a tight cluster. Lid off, look, lid on, about 20 seconds. Do not knock the cluster, because it loses heat fast and may struggle to re-form. 3

On small colonies the fact sheet asks for a look every 2 to 3 weeks on bright, calm days. Through a cold wet spring, or any other period of dearth, it asks every beekeeper to check every week or two. 1

Plenty of beekeepers will not open a hive between October and March at all, and they will tell you so. The NBU is on the other side of that argument and says it directly: briefly lifting the crown board to see whether the bees can reach their food does far less harm than starving. A clear crown board makes it easier still.

Counting what is left, without chilling the brood

If there is a super over the brood box and it is half full of honey or more, you can stop there and close up. 1 If it is empty, go into the brood box, and do it like this:

• Lift each comb halfway out rather than all the way, so the brood does not get chilled.
• Score each one for stores: none, a quarter, a half, three quarters, or full. Add them up.
• Work in from one side until you reach brood with little or no honey, then start again from the other side.
• Count a shallow frame as half a deep.
• On double brood you may only need the top box, because that is where the stores will be. If the top box is a shallow, check underneath as well.

In the active season the number to remember is two full deep combs of stores. Less than that and they may not last a fortnight, so they get fed straight away. Autumn feeding has what a full frame weighs.

One thing to check while you are in there: no queen excluder. Left in over winter, the cluster can move up through it after the stores and leave the queen below to die.

Why syrup is the wrong answer in the cold

Syrup is not a winter feed. The bees cannot process it in cold weather, so it sits there. 2 They also have to move up into the feeder to reach it, which a cold cluster will not do.

Depending on where you are, the weather and the size of the colony, bees may be unable to take syrup down and store it properly much beyond mid-October. Left standing in a feeder it grows mould. 3

There is a mechanical problem too. In the cold the sugar can crystallise in a contact feeder and block the mesh, and a rapid feeder is little use in very cold conditions. So the honest answer in January is fondant, not syrup. Making sugar syrup covers the mixes and when each is right.

Fondant, and exactly where it goes

There are two places it goes, and that is the whole choice.

• Over the feed hole in the crown board. Lay the block on with a cut in the wrapping so the bees can get at it. On a small colony, turn the crown board round so the hole sits over the cluster instead of beside it. 2
• Straight onto the top bars, over the cluster. When it is properly cold the bees can be reluctant to go up through the crown board at all, so this is the better one. You need an eke or an upturned feeder above it to make the room. 1

Put it on gently and do not disturb the cluster to do it. Then take the eke or feeder out in spring, as soon as the fondant is no longer wanted, or a colony building up will fill that space with brace comb.

Fondant has a second advantage. Bees work through it slowly, and it stirs the colony up less than syrup does, so it draws less robbing. Setting up to feed is the hardware side of it.

What a starved colony looks like

The fact sheet lists the signs, and they arrive in roughly this order. 1

• Dry cells around the brood nest. That ring normally holds nectar or honey. Dry all the way round is the first warning.
• Nibbled cappings with healthy looking pupae underneath. The bees are opening their own brood in search of food and eating it. This is the typical sign of starvation about to happen.
• Pupae on the floor or thrown out of the entrance.
• Lethargic bees. No food means no energy. They crawl into cells head first, and a colony that far gone can be lost very fast.
• A pile of dead bees on the floor, deep enough to block the entrance, with a few starving bees crawling slowly over the top of it.

Bees head-first in the cells is the sign to act on today. Not at the weekend, and not once the weather improves.

It might not be starvation

Nibbled cappings on their own are not proof. The same thing shows up with foulbrood, with a heavy varroa infestation, and with chilled brood. 1 If it is varroa you can settle it by opening a few cappings and looking for mites underneath.

The foulbrood leaflet is blunter about it. Perforated cappings should not be used as a diagnostic sign by themselves, and with American foulbrood the holes are usually ragged, sit off to one side, and have no regular shape. 4 Foulbrood is notifiable, so if that is where your mind is going, read what UK law asks of you before you do anything else.

A pile of dead bees at the entrance is not proof either. Trembling bees, and black shiny hairless ones, point at chronic bee paralysis virus instead. 5

Feeding bees too weak to feed themselves

If the colony is down to one or two combs of stores, feed it the same day, or within a day or two at the outside. 1 And if the bees are already lethargic they may not be able to reach a feeder at all, so a feeder on its own does nothing. Three ways round that:

1. Trickle it onto them. Slightly warm thin syrup, straight onto the bees between the seams. About 5 to 10 ml per seam is enough. You are not feeding the colony here, you are getting them moving so they can climb to a feeder.
2. Fill a comb. Lay an empty comb flat and trickle thin syrup into the cells on one side, with a jug or a properly cleaned out squeezy bottle. Lower it in among the bees. Do more than one frame if you can.
3. Give them capped honey. Only your own, and only from an apiary with no history of disease. Scratch the cappings open, make sure the honey is liquid and not set, and put the frame against the brood, or in the middle if they are already going.

Use the thin mix for all of this, because they can use it straight away. Making sugar syrup has it. Once they are moving they can work a feeder, and a contact feeder is the one to reach for in cool weather because it sits right above the bees. A frame feeder next to the cluster is good for keeping it going. 2