Platform for beekeeping practice and know-how

The winter survival of bee colonies is a topic that divides beekeepers because of contradictions, preconceptions, hypotheses and differing viewpoints. The experienced beekeeper relies on experience and closely monitors weather variations from November to March in order to estimate the timing of the resumption of egg laying by the queen and the volume of brood that must be kept warm. The beginner beekeeper, by contrast, is confronted with the questions raised by worried colleagues: should colonies be fed during winter or not?

What beekeepers should know about exposure, immune reactions, and protection

Among beekeepers, bee stings constitute a frequent occupational exposure, often trivialized and traditionally associated with the idea of tolerance acquired through repeated exposure. This widely held representation is based on genuine empirical observations, but it only partially reflects the documented clinical and immunological reality.

The insulation of beehives during winter has long been the subject of debate within the beekeeping community. While some studies emphasize its beneficial effects on reducing energy consumption and improving colony survival (St. Clair et al., 2022; Alburaki & Corona, 2021), others highlight its limitations and potential side effects, particularly when it disrupts the natural thermoregulation mechanisms of the superorganism (Mitchell, 2023; Minaud et al., 2024).

Some acaricides used in alternative control strategies against Varroa, such as formic acid or essential oils, do not always provide sufficient efficacy. As complementary measures, we recommend the removal of drone brood or the establishment of young colonies in spring. These interventions aim to slow the development of Varroa populations and thereby reduce infestation pressure. They have the advantage of being applicable during the main beekeeping season, whereas the use of chemotherapy would entail significant risks of contaminating honey harvests.

February is a pivotal month for the colony. Day length increases, and the queen gradually resumes laying. This resumption remains fragile: stores can become critical, temperatures are unstable, and any prolonged opening can chill the brood. The beekeeper acts mainly through observation, anticipation, and preparation, keeping interventions to a minimum.

This official factsheet describes the use of the FAM dispenser with Formivar 70% and focuses on protective measures, required equipment, key points, and a clearly structured procedure. It specifically emphasizes that formic acid (Formivar) is highly corrosive and must be handled with great care. For details and the complete instructions, the factsheet is considered the authoritative reference.

Oxalic acid is harmful to health. Vapours or dusts of this acid must not be inhaled or come into contact with the skin. It must be handled with the greatest caution. In all cases, protective goggles, acid-resistant rubber gloves, an FFP3 protective mask and long-sleeved clothing must be worn.

During treatment, make sure not to stand in the oxalic acid cloud. Colonies must be treated from the outside (not inside the bee house). As it is impossible to completely avoid contact with the vapours, we recommend wearing a half mask or a full-face mask equipped with an activated charcoal filter. This provides effective protection. Attention: filters have an expiry date and must always be stored in a sealed plastic bag.

The formation of a young colony using a nucleus with consolidated brood reduces swarming and lowers varroa pressure in production colonies. Young colonies are formed from brood frames taken from several strong and healthy colonies, from which frames are repeatedly removed in May/June—predominantly capped brood (each time one brood frame per colony).

American foulbrood is a bacterial disease. Under optimal conditions, the bacteria multiply by cell division. When conditions become unfavourable, spores are formed that remain infectious for decades. These highly infectious spores are distributed within the colony in the brood nest through the cleaning and maintenance activities of worker bees. Infection by spores occurs via the royal jelly on which larvae feed during the first 48 hours of their life. Adult bees are not infected but can act as carriers of the pathogen. A completely dried larva forming a crust may contain more than 2 billion spores.

The evaluation or selection of colonies does not concern breeders alone; it is also important for every beekeeper from the perspective of bee health. As a preventive measure, the ultimate aim is to retain only healthy and strong colonies within an apiary. This selection applies both to productive colonies and to young colonies.