On a warm May day you can see a large wasp buzzing as it goes about its business. This is a common hornet - a representative of the family of social wasps. Despite its impressive size, it is not aggressive. Vespa crabro or hornet wasp prefers to feed on fruit juice and other sweet foods. Insects live in large families with a constant hierarchy. The head of the colony is the queen - the only female capable of laying fertilized eggs. The purpose of working females and males is to serve the queen and the growing larvae.
Description of the hornet
Vespa crabro is a species of the largest wasp found in Europe. The body length of working individuals is 18-24 mm, the uterus is much larger - 25-35 mm. The appearance of females and males is almost identical, their differences are noticeable only with magnification. The number of segments in the antennae of the male is 13, and in the female 12, on the abdomen - 7 and 6, respectively. Small transparent wings fold along the back when at rest. The deep slit of the reddish-orange eyes resembles the letter "C". The surface of the body is densely covered with hairs.
Interesting fact. There are 9 subspecies of Vespa crabro in the world.
Let's get to know each other better
The classification of insects states that there is a separate genus of hornets, which belongs to the family of true wasps. Wasps that are familiar to us belong to the same family. They are called paper wasps. Thus, hornets are their close relatives. Therefore, they are very similar to them in appearance, as well as in their method of nutrition, reproduction and general lifestyle.
However, hornets have their own characteristics, both biological and behavioral. We will focus on them in our article.
Hornets are social insects that live in large families, also called colonies. By the beginning of September, their numbers can range from 400 to 800 individuals.
The family consists of one queen, several females, males and workers. Only the queen of the colony lays eggs. Therefore, to prevent mating and laying eggs by other females of the family, the queen emits a special odor. As a result, females lay unfertilized eggs, from which only drones are born.
Hornets are larger than wasps. The size of the uterus can reach 25-35 millimeters, and males and workers 22-30 millimeters. The front half of the chest and the head of the hornet are yellow. There are rings on the body - the first two are dark brown with yellow stripes, and the rest are yellow with the presence of brown spots. The body of the insect is covered with villi.
On the top of the head are three large compound eyes of a reddish-orange color. The oral apparatus of hornets has the shape of a gnawing type, but is only equipped with very strong mandibles. Females and workers have a sting, which is a modified ovipositor.
What are the different types of insects?
There are 23 species of hornets in the world, which in turn are divided into subspecies.
The most common types include:
- European, which is distinguished by red pigmentation on the head and large body. They are found throughout the Russian Federation, including Siberia. Very common in the Primorsky Territory. Also, often found in the Moscow region.
- Eastern - the body is brown in color. They live in Asia, Africa, Europe (including the vast expanses of Russia).
- Filipino - a bite leads to the death of a person. Insects are common in the Philippines.
You should know that in some countries hornets are protected by the state. For example, in Germany, a fine of 50 thousand euros will be imposed for destroying a hornet nest.
Area of residence
In the Northern Hemisphere, up to the 63rd parallel, the most common species is the common hornet. It can be found in Europe, North America, Kazakhstan, and Ukraine. In Russia, insects live over a vast territory from the European border to the Ural Mountains and Siberia. Even in the northern and eastern provinces of China they know what the European hornet looks like.
Interesting fact. Until the mid-19th century, hornet wasps were not found in North America. They were accidentally introduced by European sailors.
Wintering of insects
The peculiarity of hornets is that they lack thermoregulation. When cold weather sets in, they need to hide safely and fall into torpor. Otherwise, the insects die.
Making a nest for the winter
Insects build their homes from wood ground up by their jaws and mixed with saliva. To protect against temperature changes and other negative factors, the honeycombs themselves, in which the larvae develop, are wrapped in a wood mixture reminiscent of a paper cocoon.
The nest often resembles a pear or ball in shape. It is distinguished by amazing symmetry and precision of shape.
The larger the diameter of the wasp house, the more individuals live in it. The ability to build nests is passed on to each generation genetically. A fertilized female, the queen, wakes up after hibernation and chooses a place for the future residence of the entire swarm.
There she attaches the base and makes the first few (3-5) cells. Eggs are laid in them, the first larvae develop, from which worker representatives of the genus emerge. They also complete the construction of the hive afterwards. Nests are used only in the warm season for raising larvae in honeycombs.
Wasps settle in secluded places:
- hollows;
- animal burrows;
- under the roofs of houses;
- in the cracks of trunks;
- in rock crevices.
Wasps leave the house for the winter. Those individuals that are going to spend the winter do not specially prepare their hibernation site in any way. It is simply selected so that no one discovers the insect and accidentally destroys it. You should not be afraid that the wasp will decide to wait out the frosts in a warm human house.
When and how do they hibernate?
In mid-autumn, the hornets leave the nest and begin active mating. With the arrival of frost, they cannot maintain their metabolism and in order to survive, they hibernate. Only fertilized female hornets settle down for the winter.
The queen, drones and workers simply die. The fluid in the insect's body is represented by glycerol. Thanks to this, it does not turn into a piece of ice at sub-zero temperatures and is able to warm up and continue to function with the arrival of spring.
Where do they spend the winter?
Females always settle down for the winter in a cold place. These can be unheated abandoned premises, recesses between bricks in the outer part of the walls of residential buildings, hollows, cracks in the bark, holes, places under large stones.
Differences between a hornet and a wasp
Hornets differ from other members of the family in size and enlarged nape. These parameters immediately catch your eye. The differences are also noticeable in the nuances of color - the back, base of the abdomen and antennae of the hornet are brown, while those of the wasp are black. The basic proportions of the body structure of insects are similar; they have a thin waist, strong jaws, and a sting.
External features complement the differences in character; despite its superior size, the common hornet is less aggressive than the wasp. An attack can be provoked by approaching the nest where the hornets live in the summer.
Information. A prejudiced attitude towards hornet wasps has developed due to their impressive size and menacing buzzing sound when flying. Unreasonable fear causes active actions towards insects; a person waving his hands at it will be bitten.
Wasp eye model
Scientists have managed to construct an optical device that replicates the abilities of a wasp's eye. This is a 280 degree viewing system. Experts plan to install the unique device on aircraft, military equipment, and robots for various purposes.
The design is at the stage of improvement. Experts plan to replicate the exact model of a wasp's eye. Insects have 3 photoreceptors - near ultraviolet, blue, green, allowing them to see at relatively long distances. The wasp quickly detects movement thanks to the flickering light.
Types of hornets
There are more than two dozen varieties of hornets. Initially, insects were found only in East Asia. With the help of humans, typical inhabitants of the subtropics reached North America and Canada. In addition to the ordinary one, which is described above, it is worth considering three interesting and numerous types:
- The Asian giant hornet is the largest representative of wasps. It is not for nothing that in Taiwan they gave him the appropriate nickname - “tiger bee”. The body length reaches 60 mm, the wingspan is more than 75 mm. Its habitat: China, Korea, Japan, India, Primorsky Krai of the Russian Federation. The insect is known for its highly toxic poison, produced in large quantities. Its bite is dangerous and painful; an attack by several individuals leads to the death of a person. Japanese statistics report 40 annual deaths from the sting of the sparrow bee.
- The black hornet is similar in size to its ordinary European counterpart. It is distinguished by its black belly and brown wings. The insect is found in Transbaikalia and Primorye, as well as in India and China. An unusual fact about the development of the black hornet deserves attention. His queen deceives someone else's nest, masquerading as their queen with pheromones. The deceived family takes care of the eggs and larvae of the parasite.
- The eastern hornet is characterized by its adaptation to dry climates. The insect lives in the subtropics of Asia and America, and is widespread in southern Europe. The size of individuals is smaller than representatives of other species, the uterus reaches 30 mm, males are smaller - 16-20 mm.
Will wasps return to a hive under a roof in the spring?
After winter, the female wasps wake up. This happens when the air warms up to +15 degrees. Now they need to find a home for the warm season in order to place their offspring in it. Their appearance will not be noticeable immediately. At first, the wasps will set up their home and actively reproduce. And by mid-summer you can observe a full hive of young individuals.
Natural instinct calls the females to return to their native land. Therefore, if you do not destroy the houses of striped insects in the winter while they are empty, then in the spring a new family will settle there. How to effectively destroy a wasp nest:
- remove and throw away away from home;
- burn;
- treat with Dichlorvos or boric acid;
- sprinkle with bleach or a special repellent compound (“Raptor”, “Get”, “Alatar”).
Important: even if the nest was physically destroyed, the place where it was located must also be treated with a chemical composition. Otherwise, wasps can simply build a new home in place of the old one in their familiar territory.
You can help move the swarm to a new location, away from people. For this purpose, comfortable areas are created, protected from bright light, wind and moisture. You can lure them with sweet fruits and water with sugar.
It was not for nothing that the wasp appeared in nature. At first glance, these insects are of absolutely no use, but rather the opposite. But in fact, striped ones destroy clouds of pests in the garden in order to feed their offspring. They also promote the reproduction of flowers and plants and carry pollen. And if you do not anger them and do not interfere with the period of conception of offspring, then wasps can exist peacefully next to humans. The life cycle is short, but they accomplish a lot in a year. Until the last days, they help the offspring survive so that the food chain is not disrupted.
How do hornets—the same giant wasps that bite so painfully—winter? After all, these insects are among those animals that are not able to maintain a high body temperature. According to the logic of the structure of the physical body, at subzero temperatures insects should become a piece of ice.
However, every spring the hornets fly out from somewhere, beginning a vigorous activity of feeding and reproducing offspring. How do they manage to spend the winter, where do they hide from the cold, and most importantly, why don’t they turn into this very piece of ice?
Life cycle features
To learn more about an insect, consider its life cycle from birth to death.
Birth
A single queen gives life to an entire generation of a family of giant wasps. In the spring she finds a place to build a house for a new colony. The female makes the first honeycombs herself, then lays eggs in them. After a few days, larvae appear and require animal food. Their mother regularly goes hunting for caterpillars, beetles, butterflies and other insects. The grown larvae wrap themselves in silk thread and turn into pupae. Two weeks later, the young hornets gnaw the path of their cocoon.
Interesting. In bad rainy weather, the hornets cannot fly out of the nest, then the larvae give droplets of food to the workers.
Maturity
In July, several working males and females grow up and are ready to take care of the family. They help complete the construction of honeycombs and fly for protein for the larvae. The queen stops leaving the house and concentrates on laying eggs. How long do hornets live? The life of working females and males is very short. They grow up at the end of summer, and in September most of the individuals die. The rest survive until the first cold weather.
In early autumn, the family reaches its population peak. In the last clutch, the queen laid fertilized eggs, from which females emerged that could become new queens. Individuals born earlier had altered ovaries; their functioning was suppressed by the queen’s pheromones. Young females and males begin to swarm around the nest and mate. The insects will save the sperm obtained in the fall to found a new family. After mating, males will live for about a week. The old queen loses her ability to reproduce and is driven out onto the street or killed.
Do wasps die in winter?
In the fall, the wasps leave their nest and disappear for several months. If it remains in the same place, the first individuals will begin to return in the spring. They also begin to disappear gradually; young females disappear in October, when the temperature in the Moscow region drops to +10 degrees.
Working females are the first to die. Their life cycle is short, only a year. Before this, at the end of summer, individuals capable of giving birth to offspring mate. Then they fall into suspended animation and fall asleep until spring in order to preserve future offspring during the frost period. By the end of November, male workers die. The old queen falls asleep forever, and in the spring a new individual will take her place. Some families give birth to fertile females only at the end of August, so their cycle is slightly shifted. Even at the end of summer, the life processes inside the wasp’s body begin to slow down until they slow down so much that the insect freezes and goes into hibernation, with fatal consequences.
As a result, only the females who store the eggs survive the winter. In the spring, the swarm will recover and return to its original place of residence. In solitary species of wasps, the queens survive the winter with their offspring inside. Male hornets die in winter, but females hide until warm days arrive and survive. Wasps choose wintering places long before the onset of cold weather.
How do hornets winter?
Almost all members of the hornet colony die before the onset of winter. Only fertilized young females will remain. During the last warm days, they actively hunt, replenishing their body’s energy reserves. A decrease in daylight hours becomes a signal for the onset of diapause. This is a condition in which the body's metabolic processes are inhibited.
Where do hornets winter? They choose secluded places where they can hide from severe frosts and natural enemies - birds and mammals. Females prefer to climb under the bark of trees; the deeper they are, the greater their chances of surviving until spring. For wintering, tree hollows filled with fallen leaves, crevices in sheds, and attics are used. Females will wake up in May, when the average air temperature does not drop below 100. They will live the longest - 1 year and create a new family of common hornets.
Causes of wasps
Wasps in the house can appear for various reasons, among which it is worth highlighting the most important:
- They can be lured by various foods - meat, fish, fruits, sweet foods;
- A warm and comfortable place to locate your nest;
- Nesting for the purpose of overwintering. These insects often fly to private homes in the fall to spend the winter. Everyone knows that insects die in severe frosts;
- They can get into the house by accident. Often these creatures enter the house accidentally, for example, in search of food or water. If one wasp flies into it, then soon a whole swarm will live there.
Knowing these reasons will help make the process of controlling these insects easier. It is enough to simply create conditions in which these creatures will not be able to live.
Nutrition
Hornets can be called omnivorous insects; they are dexterous hunters, but at the same time lovers of plant food. What do hornets eat? Adults have a wide gastronomic diet:
- nectar;
- juice of ripe soft fruits (peach, pear, apple);
- berries - raspberries, blackberries, strawberries;
- aphid secretions;
- honey.
Predatory insects, except for the queen, eat their relatives only at the larval stage. Working individuals with enviable diligence shuttle between the nest and the hunting site, bringing spiders, centipedes, and worms to their offspring. Hornets cut up prey with powerful jaws, feeding protein to the growing larvae and queen, which requires strength to lay eggs. Large wasps often attack individual bees and hives. One large individual is capable of tearing apart up to 30 honey plants.
Interesting fact. Hornets do not have a long period of sleep; they are active at any time of the day. To rest, they simply freeze for a few minutes. Numerous hungry larvae, the number of which sometimes reaches up to 500, require a lot of food. A family of predatory insects is capable of destroying up to 0.5 kg of garden pests daily.
What do they eat?
Nature created hornets as predators. Therefore, they mainly feed on other insects. They not only eat live insects, but can also feast on the carcass of a recently deceased animal. Hornets eat only those bodies in which the process of putrefaction has not yet begun. The diet of striped insects is supplemented by sweet fruits and berries, which are already beginning to decompose.
They love overripe fruits: plums, apricots, peaches, strawberries, raspberries, blackberries and grapes. With pleasure they feast on all beekeeping products. A squad of several hornets is capable of destroying an entire swarm of bees. They eat and take back to their nest everything they find in an empty hive. Thus, they can be safely classified as omnivores.
Building a nest
The place for the hornets' nest should be secluded, protected from bad weather and drafts. In nature, these are tree hollows; a reduction in their number forces the queen to seek shelter close to human habitation. Sometimes females choose a nesting box, which soon becomes completely filled with tiers of honeycombs, requiring them to find a new location. Insects can simply hang a nest on a tree branch, hide it in a rock crevice, a steppe hole, or in the attic of a house or outbuilding.
If there is no rotten stump or other wood nearby, working individuals cause significant damage to young branches. With strong jaws they scrape off the bark, which they use to build a nest. Ash or birch wood is mixed with saliva and becomes the building material for the hexagonal honeycomb walls of the nest. Born architects can create real masterpieces.
The nest material resembles cardboard or corrugated paper. The expansion of the structure is carried out in tiers, from top to bottom. From the first leg, attached by the uterus, it will grow to 5-7 tiers. Honeycomb plates have up to 500 cells. The outside of the nest has the shape of a cocoon. The thickness of the protective walls is several centimeters. Interestingly, the color of the cocoon depends on the wood, the most common being brown. The shape of the nest changes depending on the stage of construction. Typically, insects flock to their home to rest at night. How many hornets are in the nest? Their number depends on the stage of development of the colony, favorable conditions, and abundance of food. The colony can number 300-400 individuals.
A large amount of remains of eaten insects, corpses of dead hornets, and other debris accumulate on the ground under the building. This landfill emits an unpleasant odor and becomes a source of parasite development. They can lead to the death of the colony.
Information. Despite the colossal efforts spent on building the nest, the insects will not settle in it next year. The young queens will find a new home.
Fighting wasps in the autumn-winter period
As they say, prepare your sled in the summer, and start fighting wasps in the winter. Just because wasps have left their nests for the winter doesn't mean they won't return in the spring. Therefore, certain work must be carried out while there is no one in the nests, or rather, as soon as the temperature outside the window drops to 9 - 10 degrees. This makes the task much easier.
First of all, it is necessary to carefully examine their possible wintering places - attics, sheds, all dark and dry corners. Look into every crevice where wasps could possibly live. If boards and other things are piled up on the site “just in case,” they should be moved to another place or rearranged. If wasps were hiding there, then if they were left without a roof over their heads, they would quickly die.
If you find a nest or something similar to it, remove it carefully and destroy it. The place where you found the remains of a wasp nest must be watered with something with a strong and pungent odor. Kerosene, for example, or dichlorvos. These measures will lead to the fact that next year the wasps will look for other nesting places. In addition, before snow falls, it is necessary to collect and burn fallen leaves, if possible, remove dry branches and trees from the area, or peel off the bark from them. Thus, we will significantly reduce the number of places where wasps can hide for the winter. The right owner will not forget to replenish supplies of insecticides. In winter, they are needed much less and, accordingly, their price is lower. Whether to collect plastic bottles for traps or not is something everyone will decide for themselves. Considering that almost all liquids are sold in such bottles, it is not advisable to collect and store them all winter.
How does a hornet bite?
The insect has a sharp and smooth sting that stings quickly and painfully. The insect's venom is not more toxic than that of a bee, and therefore the symptoms of intoxication are similar. The consequences of a bite depend on the body's reaction. Even with strong immunity, swelling and redness appear at the puncture site. If an individual manages to inject a large amount of poison by inflicting several sting strikes, inflammation occurs. With increased sensitivity to the toxin, anaphylactic shock occurs. In this case, urgent hospitalization is required.
Why does a severe allergic reaction occur? It is caused by histamine, a substance present in the chemical formula of the poison. Histamine accelerates the allergic effect, so even with a strong immune system, malaise appears. In Russia, death from the bites of the common hornet has been recorded only a few times in the history of observations. The largest number of deaths occur due to giant hornets in Asia.
The sting for hornets is a weapon of defense. It is a modified ovipositor connected to a gland that produces a toxin. The absence of notches makes it easy to remove the weapon from the wound. The introduction of poison occurs through muscle contraction. How does a hornet sting? It pierces the enemy's skin and injects a drop of toxin. The presence of a substance that acts on nerve endings causes instant pain. At the time of the bite, the insect does not use up its entire supply of poison. Otherwise, it will remain unarmed during the next attack. It takes some time for the poison to recover.
Attention. Bites in the neck area of the mouth are especially dangerous; they cause swelling of the larynx and block breathing. Due to immature immunity, children are at greater risk than adults.
For hunting, insects use their jaws, tearing prey with them. The production of potent poison and a long, strong sting indicate that they often have to repel enemy attacks on the nest.
How do these insects survive winter?
Hornets are social insects like bees or ants, in which the nest is the basis for the well-being of the species.
Hornets' homes are structures made of paper, which they make from the young bark of trees.
The nest is a round-shaped structure with honeycombs inside. This ball is hung somewhere in a secluded place. Its purpose is to place eggs in paper honeycombs and then feed the larvae there.
Insects are creatures that generally do not like to migrate far. Moreover, most of these species do not migrate at all. They prefer to live where they were born. Any mass movements of grasshoppers, called locusts, moths and other arthropods are rather an exception to the rule. So, if an insect lives where there are harsh winters, then it is adapted to survive them.
The whole rhythm of the existence of hornets in the harsh conditions of a temperate climate is similar to the rhythm of life of bees and ants. To survive and produce offspring every year, you need to sacrifice something or someone.
Ants and bees sacrifice males, who quickly die after mating. This is done in order not to waste resources on already useless individuals. In hornets, the females are in charge. They are the ones who survive the winter, and then become the founders of a new generation.
The young female leaves the parental nest towards the end of the warm period of the year, that is, at the end of August or beginning of September. At this time, the nest can reach a diameter of more than half a meter, and a length of about a meter.
During the period of maximum number of sexually mature individuals, they all leave the nest, swarm and mate. This phenomenon may seem strange, because mating occurs before the onset of cold weather. However, this is precisely the logic of successful wintering and further reproduction of offspring.
Soon after mating, the males die, and the females begin to lead a free and solitary lifestyle. They feed heavily, and in between searching for food, they look for a secluded place for winter shelter.
The wintering place should be such that a pregnant female (and this is how they sleep), having fallen into suspended animation, is completely safe. She should not be found by enemies, the cold wind, and most importantly, people. Hollows, cracks in rocks, various small cavities on the outside of human dwellings, unheated buildings, shelters under stones, fallen trunks, etc. are suitable for this.
None of the wintering insects hide inside human houses. The fact is that when cold weather sets in, when the temperature drops below 0°C, the water in the insects must freeze. However, this does not happen, because in the body of these creatures, water is replaced by glycerol, which inhibits all life processes, but most importantly, it does not turn into ice and does not break cell walls.
Danger to humans - myth or reality?
The behavior of the common hornet differs significantly depending on the distance from the nest. During flights for food for themselves, the queen and larvae, they behave peacefully. But, when a real or imaginary danger to the nest appears, the hornets mercilessly sting everyone who falls into the zone of their aggression. There are always several individuals on duty near the house for protection. In the event of an attack, they give a special alarm signal that gathers the whole family.
How dangerous are hornets to humans? The strong venom of insects when bitten causes an attack of pain. Unpleasant sensations and swelling may persist for several days. The symptoms are similar for all victims, only the intensity of the manifestation differs.
Insects jealously defend their nest, but with careful approach, you can monitor the life of the colony. The main thing is to remember a few rules of behavior:
- do not make sudden movements;
- do not touch the nest with your hands or a stick;
- do not interfere with the flight of the hornets.
It is recommended to destroy the nests of the common hornet only if there is an increased danger in the neighborhood. For example, if it is located in a used room or next to an apiary. Predators are the worst enemies of bees and beekeepers. People with hypersensitivity to poison should get rid of the neighborhood, otherwise they will be in danger. In general, large wasps are peaceful neighbors, which will also help with the destruction of pests.
Bottom line
To summarize, I would like to highlight the main thing - the meaning of hornets for people is very contradictory. On the one hand, they help - they destroy insects: flies, mosquitoes, ants and numerous agricultural pests, and also clean the gardens of overripe fruits.
But on the other hand, they destroy bees and can bite humans. If you are bitten by an insect, you should immediately take an antiallergic drug, and if you have multiple bites, immediately seek medical help. Thus, if you are not a beekeeper, then these large striped insects are more likely your friends than enemies.
