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Depiction:
The pavilion apiary dates back to the 19th century; its design was intended for storing baskets and hives with rear access. The apiary was meant to protect bees from wind, rain, and theft. The “Swiss” rear-access hive remains the most common management system in German-speaking Switzerland. Outside Switzerland, beekeeping is practiced mainly using multi-super hives.
In nature, bees rear queens in spring during swarming in order to multiply colonies. They also rear queens in other situations, for example when the queen no longer performs satisfactorily after several years of egg-laying, or when the queen is accidentally lost. In these particular cases, queen rearing is not associated with swarming.
Insects are not insensitive automatons: bees, wasps, flies, or ants display remarkable cognitive and emotional capacities under laboratory conditions.
Recent experiments suggest that bumblebees may experience optimism, joy, and possibly even pain. These findings raise important ethical questions concerning the treatment of insects in laboratory settings, their breeding, and the use of pesticides.
When a bee changes its role in the hive, its DNA adapts
Bees each perform a specific but flexible role within the hive. Older individuals may, if necessary, take over tasks usually carried out by younger bees. Until now, it was unknown that such behavioural changes are accompanied by adaptations at the DNA level. Each role is in fact associated with its own distinct methylation pattern.
In 2019, it came as a surprise to learn that the Varroa mite does not feed on the bees’ haemolymph but pierces their cuticle in order to ingest the so-called fat body (► see article).
Research is progressing very rapidly, and today it is known that the saliva of the adult Varroa mite allows it to keep the opening it has pierced through the membrane of the nymph or the imago wide open, in order to liquefy and then suck up the fat body. A salivary enzyme (chitinase) appears to reduce the bee’s immune defences and to play an important role in the survival of the Varroa mite … it is therefore natural to envisage blocking this enzyme as a future strategy in the fight against this deadly parasite …
Those who have already used the excuse that “housekeeping is not in my DNA” to try to avoid this chore may not have been entirely wrong. Indeed, at least in honey bees, certain shortcomings in hive hygiene appear to be linked to the overexpression of genes that impairs the detection of odors released by diseased or dead larvae.
by ALAIN SATABIN
As early as Antiquity, mathematicians observed that the shape of honeycomb cells in beehives optimizes the ratio between available volume and the amount of wax used. Demonstrating this, however, is another matter … one that has still not been fully resolved.
The deformed wing disease virus (DWV) is one of the most widespread viruses in Apis mellifera and one of the least virulent. In the absence of facilitating factors, it causes only a covert infection, that is, an infection without clinical signs.
It sticks, it stains, and we sometimes curse it when inspecting our beehives; yet it gives beekeeping one of the fragrances that contribute to its charm and is also an increasingly sought-after product, representing a growing source of income for beekeepers. Although omnipresent in our hives, propolis is the result of a harvest and a processing effort that is anything but simple for the bee. A demanding but indispensable task; for this resinous substance, whose medicinal properties have been appreciated since Antiquity, fulfils multiple functions within the colony.
by ELIZABETH TIBBETTS AND ADRIAN DYER
Recognizing the facial features of conspecifics does not require a brain as complex as one might imagine: some insects, notably bees, are remarkably adept at this.
Chemical control of harmful organisms has been known for millennia. The application of sulfur, lead, or arsenic was already practiced in ancient Greece. Closer to our time, the insecticidal properties of tobacco (nicotine) were known as early as the 17th century. In the 19th century, chemistry made major advances, and new copper sulfate–based compounds made it possible to control fungal diseases of grapevines. In the 20th century, mercury salts began to be used for seed treatment. Because of their toxicity, these substances were quickly banned.
In beekeeping supply stores, frames are available pre-assembled with or without wax, as well as frames to be assembled. For a pre-assembled frame with wax, a minimum cost of CHF 10 should be expected.
The art of economy (Janine Kevits)
Winter represents a formidable challenge for fauna, as it must cope both with cold temperatures and with food scarcity. Some insects have “chosen” to avoid it by migrating to warmer regions; this is the case, for example, of the painted lady butterfly. Others concentrate their chances of survival on a few individuals—reproductives that are abundantly nourished during the favorable season and whose task is to found a new colony on their own the following spring; this is the strategy of wasps, hornets, and other solitary bees. The honey bee, by contrast, has found a different path: it is the powerful organization of the colonies it forms that enables it to meet this challenge, by implementing two means that are entirely original in the insect world—on the one hand, the storage of reserves, and on the other, the reorganization of the colony to form the winter cluster, a system characterized by the absence of brood and by modes of functioning that differ fundamentally from those of the summer colony.
Biotechnical control methods are increasingly being promoted in the fight against varroosis. Among these, techniques that induce significant interruptions in brood development are often discussed. However, such methods are still rarely used by beekeepers, except on an experimental basis. This article analyses the relevance of brood interruption and the different techniques derived from it.
Below, you can observe in real time the variations in hive weight and the changes in colony temperature in different apiaries located in the plain and on the slope of the right bank of the Rhône.
The parasite capable of chemically mimicking two bee species
Researchers from the Institute for Research on Insect Biology (CNRS/Université François Rabelais de Tours) and the “Bees and Environment” laboratory of Inra, in collaboration with American and Chinese colleagues(1), have shown that Varroa destructor, a parasitic mite of bees that is able to imitate the chemical composition of the cuticle(2) of its host, can also modify this composition depending on the species it parasitises. This remarkable adaptive capacity could explain how this parasite of the Asian honey bee was able to colonise the European honey bee during the 20th century, thereby contributing to the decline of the species. These findings were published on 3 June 2015 in the journal Biology Letters.
As will be clear, effective control of varroa relies on anticipation rather than on reaction alone. The objective is to keep infestation levels low throughout the season in order to preserve the colony and prevent a high parasitic and viral load. Particular emphasis is placed on protecting the winter bees so as to ensure that the colony can restart under the best possible conditions. Above all, the strategy must be adapted to the season in progress. Each year is unique, and climatic variations require increasing adaptability in order to keep varroa under control.
Reviewed for you by Claude Pfefferlé
But where does the queen fly? The unprecedented case of a foraging queen! Another dogma is being challenged…
In the countryside of northern Sardinia, an Italian honey bee queen (Apis mellifera ligustica) was observed for the first time in spring 2021 while foraging on a borage flower (Borago officinalis), most likely during an orientation flight prior to mating.
