Bee Nutrition, Feeding for Survival and Feeding for Stimulation
With winter comes the question about feeding. To get a colony through the winter and early spring if the beekeeper has taken off most of the honey surplus, the bees will need feeding at some stage.
The natural foods of bees are nectar and pollen. Nectar is the primary source for carbohydrates, and pollen for protein, fats and minerals. Most of us know that the bees turn the nectar they collect into honey, which can be stored for indefinite periods and used by the bees when there is a dearth of nectar, such as in the winter, as their source of energy. Energy that they need to keep warm and active, as well as fly a cleansing flight when the weather permits. Pollen is also stored, packed in comb covered by a drop of honey for preservation, usually close to where the brood was reared and where the winter cluster is maintained.
Let’s talk about feeding carbohydrates. With the current high value of honey compared to sugar, most commercial beekeepers will feed sugar of some sort. But the hobbyist may still save frames of honey to feed back to their bees. The honey the bees produced will be the best source of carbs, and it saves having to decide whether to feed raw sugar, dry white sugar or sugar syrup. Sometimes, however, we miscalculate and we haven’t kept enough honey to feed back, so feeding sugar to save the colony is the only option. So what to feed and when are the questions that need to be answered.
In the winter, we don’t want to stimulate the queen to begin laying, so it is probably best to feed a dry sugar. I have been told by a very experienced beekeeper that in this instance, it is better to feed raw sugar (NOT brown sugar) as it has some moisture in it, and that allows the bees to more easily work it and take it up. Using dry white sugar means that the bees need to collect water to be able to work the sugar, and again if the weather doesn’t permit them to fly, the dry white sugar may be of no benefit. In this case it might be a good idea to provide a source of water in the form of a small damp sponge in the top feeder tray that the bees can access to work the sugar. That brings up the issue of what sort of feeder to use. In feeding raw or dry sugar, a top feeder with lots of room is ideal. (Of course you would not put the chimney cap on when feeding in this way.) Sugar in this form will not stimulate the queen to lay.
As we enter early spring, the real danger time for hive starvation, I think that feeding heavy syrup is appropriate. It is easily taken up, close to the consistency of honey, and has less of a stimulative effect than thin syrup. Again, to minimise the stimulative effect, and to avoid the bees taking it all up quickly which is not the objective, being able to restrict the access to the feed is wise. Here a top feeder with limited entrance sizes, or internal division feeders with bee ladders that restrict the number of bees that can access the feed at any one time, is a good choice. My preference when feeding syrups is the internal division feeder as it is close to the winter cluster. We want the bees to easily get to the feed to avoid losing any to starvation.
When we come to mid-spring when we want to stimulate the queen to lay, the division feeder is ideal. A light syrup, but still with restricted access is what we now want. It would be best if the feed of about six litres were taken up not faster than a week. This simulates a nectar flow and will stimulate the queen to begin laying. If it is taken up too fast and stored away, the queen might not get the message.
As an aside, I avoid any external feeders or entrance feeders as I think this can generate robbing activity or attract wasps. Also external apiary feeders in my estimation can do the same, and often the strong hives dominate the communal feeders and the weaker ones continue to struggle with access.
When preparing sugar syrups, I always use a white sugar and for heavy syrup mix one litre of water with two kilos of sugar. This needs to be heated to get it to dissolve because it is close to the maximum concentration. You may need to add just a dribble more water to get all the sugar dissolved. For light syrup I use a one to one mixture. It is important not to make more than you will use immediately. Sugar syrup bought commercially is pasteurised in the process of making it, but most home made syrup isn’t, unless you boil it for a few minutes. If this isn’t done, over a matter of a few days the yeast will build up and ferment making alcohol, and this is poisonous for bees. So stay safe and just make what you will need for the next day or two. And always carry your syrup to the hives in clean containers.
I’ve copied this little paragraph by Tim Tucker, current president of the American Beekeeping Federation, that is clear and concise on how colonies can starve in the spring.
“Welcome Back! I am sure everybody is getting bees ready for spring now and doing stimulative feeding on hives that are light in stores or just short on bees. Those who haven't been keeping bees for more than a year or two will often make the mistake of thinking that the bees have made it through the winter and they will get by on their own from natural sources of nectar and pollen, but while lots of early trees and bushes may have pollen there is little or no nectar available right now. When these early pollen flows start it stimulates the bees to begin rearing brood, and three to five weeks down the road there are lots of bees that have been raised and that process uses a lot of stored honey, which can deplete the colony of stores very quickly. If they run out of stores before a good spring honey flow begins, they can starve to death in just a few days with this expanded population. So be sure to check your hives for available resources of honey and pollen and make sure they have good weight.”
Pollen and Pollen Substitutes
Protein is essential for brood development, nurse bees’ production of royal jelly, and feeding the queen. Because of the great need during the spring build-up, it is important to check whether pollen is coming into the hive, and the stores of pollen when you are planning stimulative feeding of sugar. We are fortunate in most of New Zealand that we have some good late winter/early spring sources of pollen, a primary one being gorse. On the negative, gorse being a noxious weed, most farmers are diligent in removing it. Having said that, many natives provide a good varied source of pollen, and I often sit in wonder in the spring as the bees come in with multi-coloured packages of pollen. I know that they will be well supplied with a good balanced diet.
Having checked the pollen stores, and watched how much is coming in, there may still be a need to help. It is best to have planned ahead, and in the autumn taken a good frame or two of stored pollen out of each hive to save for the spring. These are best kept in the freezer, because even with their little drop of honey capping them, they can dry out and go mouldy. Another option is to collect pollen using a pollen trap. Most hives gather much more pollen than they will need during the build up, and capturing even a week’s worth of pollen, drying it and sealing in a moisture-proof container is a good plan. It can be fed to the hive in a top feeder, or using a communal feeder placed about thirty or forty metres from the apiary. Use a bucket with a honey gate. Put the dry pollen in the bucket and leave the honey gate wide open. Add a few spoons of honey by the entrance in the bucket and hang it in a tree and the bees will find it. This will keep it dry but allow the bees good access.
Okay, you’ve checked everything and you think there is a need to feed pollen and you haven’t got any saved. So a supplement or pollen substitute is the last option. In my experience and searching for a complete pollen substitute, I have been disappointed. Ceracell has wanted to add a pollen substitute to its range, but frankly we haven’t found one that stacks up and doesn’t at some stage contribute to nousema (bee diarrhoea). There has been a real push by some suppliers and manufacturers of pollen substitutes, suggesting that they are essential in colony management, but from all the literature and courses I have attended on bee nutrition, they should be used sparingly as prolonged feeding of protein supplements will result in short-lived bees. In fact the latest course I attended, one researcher found that after the age of eight to ten days, adult field bees do not need any protein. Adult bees older than that that were fed high protein diets died. They are incapable of digesting protein and their guts were full of protein preventing the carbs from getting in. Protein then is only needed for the nurse bees to produce bee bread and royal jelly to care for the brood and the queen. So only feed pollen substitutes as a last resort and only in the spring when there is a high demand for protein for the growing brood.
Here are some useful links if you want to read more on feeding bees and bee nutrition.