Practical Beekeeping – Healthy bees by natural keeping

Fresh pollen not concentrated feed

Wolfgang Ritter

Keywords: balanced nutrition, bee forage, pollen supplement

In an intact environment with a variety of flowers, swarms of wild honey bees settle in nesting places offering everything that they need. Today this is more difficult and beekeepers have to care for the survival of their bee colonies. While lack of carbohydrate can be met to some extent, very little is known about proteins.

Honey bees are strict vegetarians and balanced nutrition facilitates optimal development of the bee colony. Important food components are proteins, minerals, fats, vitamins, carbohydrates and water. If one or more of these are missing, colony strength decreases and each bees’ life is shortened – suffering more because of diseases, and this often ends in death of the whole colony.

As beekeepers we should constantly survey our colonies’ food stocks. Within a flight radius of up to three kilometres, a large variety of forage should be available throughout the season. Some beekeepers take care only that bees gather enough nectar and/ or honeydew with the aim of taking a good honey harvest, and they do not pay attention to pollen supply. Pollen is the only source of protein and it provides also other important nutrients. Depending on colony strength and the season, a colony needs 20–55 kg of pollen every year. Due to seasonal variation in vegetation, pollen supply varies considerably during the year.

Fluctuating pollen supply

The pollen supply in Germany (temperate climate with a forage break in winter) shows a critical phase in spring, between cleansing flights and the beginning of fruit tree blossoming, when older winter bees are replaced by newly reared young summer bees within a short time, and a sufficient supply of pollen is crucial. Hazelnut is often too early but some willow species such as the sallow are important sources of pollen. From April to June, pollen variety is extremely good, because most flowering plants are blooming during long daylight hours. From July onwards (when daytime is getting shorter) variety begins to decrease. It can then be necessary to migrate colonies to nectar plants known to be also good pollen providers. American goldenrod Solidago is an important plant that flowers in summer and during harvest. Himalayan balsam Impatiens glandulifera also supplies a late pollen source. However the spreading of these non-native plant species should be avoided because beekeepers are committed to environmental protection. It is much better to use late flowering indigenous plants such as cornflower, mustards and trefoil.

Quantity and quality of pollen

The value of a pollen source is often judged by the frequency of bee visits. However, this is not a firm indicator of good provision for a colony. How much pollen needs to be gathered depends more on the content of crude proteins. Rape pollen contains 25% crude protein, while maize pollen contains 15%.

The real value of a certain pollen for the bee colony is defined not only by its crude protein content, but also by its composition.

Proteins consist of amino acids, ten of which are classified as essential for bees. Bees need different quantities of all of these. If one or several of the amino acids are absent, or present only in small quantity, the bee colony tries to balance this by an increased frequency of pollen flights. Pollen with low crude protein content, yet with a small amount of the most important amino acids, may be critical for a colony.

Fat content seems to be adequate in all kinds of pollen. It is mainly the fatty acids that are important for bees.

Little is known about bees’ vitamin requirements. It is possible that they need B complex vitamins as do other insects. Vitamins do not persist in stored pollen, and so the value of pollen stocks is often overestimated. If pollen is infested by bacteria or mildew it becomes harmful for bees. Best for the bee colony is freshly harvested pollen – from as many different plant species as possible.

In spring in temperate climates bees use their first foraging flights to gather hazelnut and willow pollen

All photos © J Schwenkel

Layers of pollen in the cells indicate the availability of a variety of bee food

Large stocks of pollen alone are not sufficient to encourage breeding. Freshness and variety are what matter

Positive and negative pollen contents

Newly gathered pollen contains – as well as the pollen that the bees store in the cells (bee bread) – many so-called ‘good’ bacteria and fungi. These antagonists (opponents) in the gut flora and in the nest are essential for the bee colony’s resistance to numerous diseases. In a field test, those colonies that fell ill from chalkbrood showed only a few (quantity and species) of these bacteria in the intestinal tract. Many of these bacteria enter the colony via pollen. The number and type of bacteria contained by pollen depends on the plant species and also the region where the plants are growing. A varied diet with many different kinds of pollen must therefore be the aim.

Gathered pollen may contain also pesticide residue. Depending on the substance(s) and their concentration, brood damage is often the result. But even sub-lethal doses may change bees’ behaviour and weaken their immune systems. Therefore, agro-industrial areas should be avoided as far as possible.

Pollen diversity instead of concentrated feed

Many beekeepers believe that by using feed such as soya flour to replace pollen, something positive can be initiated. Here much is promised but only rarely have sufficient tests been carried out. Not everything is valid for every location. Sometimes there can be more damage than good. The fact is that we know little about the importance of certain constituents of pollen for bee health. The requirements of growing brood and adult bees are different. Therefore we are groping in the dark regarding the appropriate composition of feed as a pollen supplement.

We must conclude that bees are weakened and made ill not only by Varroa and pesticides, but also by poor food and bad nutrition. You should not make the same mistake as often made in industrial animal keeping to substitute by giving bees concentrated feed. This could cover at least the basic requirements. It is much better to choose the apiary site at the start according to the bees’ needs and to improve food sources in the vicinity. A varied diet is a precondition for strong resilience and good health - not only for bees! In short, natural beekeeping is only possible if bees are naturally fed.

**The original article has checklist on 'Are my bees in a position to feed themselves naturally?' which is not available on this mobile friendly version.

Author details OIE, Reference Laboratory at CVUA Freiburg, Am Moosweiher 2, D79108 Freiburg, Germany ritter@beehealth.info

Bfd acknowledges www.diebiene.de as the original source of this article