The defensive behavior of bees

The defensive behavior of bees

Why do bees sting? Bees sting by reaction, to defend themselves and protect the colony, especially the queen.

The defensive behavior of a bee depends on a number of factors:

  • climatic conditions: wind and thunderstorm make bees more aggressive;
  • color: light colors are less aggressive than dark colors, which explains the white color of beekeeping clothing;
  • ovarian development: orphan colonies are partially composed of workers whose ovaries develop, which leads to a rise in the level of aggressiveness;
  • movement: sudden and violent movements trigger defense behavior more quickly;
  • smell: the bee does not like the smell of mammals; other odors (hair spray and lotion, chemicals) can also increase aggressiveness;
  • the time of year: the level of aggressiveness remains very low during the honey flow;
  • the bee breed: heredity influences the level of aggressiveness.

Faced with the danger, worker bees secreted an alarm pheromone, 2-heptanone, produced by their mandibular system. This pheromone puts the colony on alert.

This ketone substance can be confused, by bees, with other ketone substances, contained in certain nail polishes or with the benzophenone used as fixative in almost all the perfumes, from where the risks of stings more important for the people who are more important. use nail polish, perfumes, deodorants and other cosmetics.

When it does, an attack pheromone is common that attracts other guards who, in turn, can sting. This attack pheromone, isoamyl acetate, is produced by cells lining the venom pouch. If a bee stings, this gland continues to give the attack signal. The emitted pheromone, which smells of bananas, makes the other bees more aggressive and incites them to sting. This is why beekeepers smoke the stung part to hide this message and stop the aggression. For the others, flight or good clothing protection is then necessary. Recent studies have shown that the blasting device also emits the alarm pheromone 4-11-eicosene-1-ol.

When a worker bee stings, the venom is injected into the victim. The quantity and quality of the venom is highest (0.3 mg) when the worker is 15 days old, during which time she performs the function of guardian.

Dard d'abeille microscope

The retractable sting, located at the back of its abdomen, is rough: once planted in an epidermis, the bee can no longer remove it, the sting is then torn off with the venom pocket. When the stinging bee tries to escape, it loses its defensive weapon and will die soon after due to the tearing of its abdomen. The bee only has a few hours to live at most. It can therefore sting only once, unlike hornets or wasps whose stings are smooth.

Our first reflex is generally to remove the sting: this gesture is useful if it is well executed. If the venom sac is compressed, any remaining contents are then injected under the skin. It is therefore a question of swiping a fingernail, a credit card, or a sharp object close to the skin to remove the stinger without squeezing the venom bag.

enlever le dard

It only remains to disinfect and possibly apply an anti-inflammatory cream. In case of attack on the fingers, remember to quickly remove the rings (before the onset of edema) and remove the bracelets in the case of the hands.

The darts remaining in the clothing can impregnate the same clothing with pheromones which will trigger a new attack during the next visit: it is therefore advisable to wash the protective clothing frequently.

The vulnar apparatus

Appareil vulnérant abeille ouvrière

Only female bees have a sting. The vulnar apparatus, or sting, is actually a modification of the ovipositor, the organ used to deposit the eggs laid in parasitic insects. The vulnar apparatus includes:

Two barbed bristles which constitute the dart and which slide inside a swollen piece of chitin, the throat;

Two sheaths that protect the sting;

Venom glands. The acid gland supplies the venom reservoir, the swollen part of the throat and the alkaline gland which facilitates the lubrication of the sting;

A venom bag where it is kept;

Chitinous parts and muscles that allow the exit of the sting and the injection of the venom.

The sting or sting present on female bees is found not only in Apis mellifera, but in all aculeate hymenoptera among which are wasps, hornets, bumblebees and wild bees.

Sting reaction and allergy to bee venom

The bee sting usually causes sharp pain accompanied by local inflammation; it is generally not dangerous. Many external applications called appropriate (ointment, ice cubes, herbs, ...) are practiced and associated with taking tablets to control pain. Even without doing anything, this normal reaction disappears after a few hours or the next 2 to 3 days.

In case of a severe allergic reaction, consult an emergency doctor. The reaction to a sting becomes abnormal when manifestations occur elsewhere than at the site of the bite. For example: swelling of the face, general hives (redness), change of voice, difficulty swallowing or breathing, asthma attack, weakness, persistent vomiting, loss of consciousness, shock. In case of one or more of these symptoms, act quickly: meet a doctor or take an antihistamine and present yourself urgently to the nearest health center.

In the event of a very serious allergic reaction, leading to anaphylactic shock, an injection of adrenaline should be given within a few minutes. The injector pen must always be available. Besides, two pens are better than one, in case of malfunction or if the first injection is not enough. Adrenaline is stable at 25 ° C, therefore storage in the refrigerator is recommended only during heat stroke.

To engage in beekeeping, it would be necessary to make sure that one does not manifest any serious allergy to the sting and to the venom of bee. If this is the case, it would be better to abstain from beekeeping and to be part of another link in the beekeeping development chain.