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Depiction:
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.
The adaptive strategies of imitation make mimicry a model of a complex coevolutionary mechanism involving a first species acting as a model (e.g. Apis cerana) and a second, imitating species (e.g. Varroa destructor), very often parasitic. Varroa destructor, a parasitic mite of bees, has the ability to mimic the chemical composition of its host’s cuticle; moreover, it is also capable of modifying this composition according to the species it parasitizes.
Do you recognize the diseases?
Take the test: try to assess the diseases!
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The major concern of beekeepers at present, in our regions, is the approach of a disease coming from the East […] [known as] varroosis. […] It is a parasite that feeds on the blood of bees, which die from exhaustion. First detected in Siberia, the disease is spreading across the whole of Eurasia; it appeared in Russia, then in Eastern European countries, and has reached the Federal Republic of Germany. France and Switzerland are currently spared. Bees are not imported from countries affected by the scourge, which makes it possible to delay (or even halt?) the advance of the disease.
L’impartial, 23 March 1983.
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.
Bees play an essential role in our ecosystem because of their primary function, pollination. This activity enables plants to reproduce. Alongside wasps and butterflies, bees are among the most efficient pollinating insects. However, they remain a species that is severely threatened by various factors.
Asian bees have developed an extraordinary technique to defend themselves against attacks by giant hornets. They cover their hive with animal droppings.
Pheromones are key elements of animal communication: they are released to convey specific messages such as sexual attraction, aggression, recognition of conspecifics, etc., to members of the same species.
Figure: Proboscis extension: appetitive response of an immobilized bee to a sugar-solution reward that has contacted its antennae. Bees exposed to pheromones of different significance modify their proboscis extension behavior, thereby demonstrating the impact of these pheromones on the evaluation of the received food reward. © Martin Giurfa