Black widow spider or karakurt. Description, photo, video

Stretch film is a very convenient packaging material with high elasticity, strength and almost complete permeability to light. For this reason, many summer residents began to actively use it to cover greenhouses and greenhouses. So, a greenhouse made of stretch film - how to make it yourself? We will talk about this further. Reviews indicate that working with this material is quite simple, but care and precision are required.

Migration of the poisonous Karakurt (Black Widow) to Russia. Video (00:04:44)

In recent years, the poisonous Central Asian Karakurt spiders have increasingly begun to migrate to the southern and central zone of Russia: Rostov region, Krasnodar region) and the Southern Urals (Orenburg region) and Ukraine (Kirovograd, Dnepropetrovsk, Kharkov, Lugansk, Kherson regions). They were also often seen in the Moscow region! The reason could be either global warming or simply a hot, dry summer and warm autumn. Global climate change is leading to the fact that the border of the arid zone is steadily moving north. There is also devastation in the countryside when active agricultural work is not carried out. Abandoned fields and farms, where no one will disturb karakurts, are a wonderful place where they breed and multiply. The bite of an adult female can be dangerous to humans and can kill a camel or horse, but the venom is safe for goats and sheep. Karakurt (Latrodectus tredecimguttatus) or steppe spider is a species of poisonous spider from the genus of black widows. Distinctive features are thirteen dots or spots on the upper side of the abdomen. Found in desert and steppe zones (Central Asia, Iran, Afghanistan, the Mediterranean coast, Crimea, the Caucasus, as well as America and Australia). Karakurt females begin to migrate in June-July in search of a suitable place for breeding. And it is at this time that most bites occur. After a person is bitten, a small red spot is visible at the site of the bite, which quickly disappears, but then the poison begins to act, and a sharp pain engulfs the site of the bite. Strong excitement begins, the victim experiences an inexplicable strong fear of death, spasms and suffocation, from which people with a weak heart most often die. After 10-15 minutes, terrible pain appears in the abdomen, lower back and chest, and the legs go numb. Headache, dizziness and vomiting are often observed. Characterized by blueness of the face, bradycardia and pulse arrhythmia, and the appearance of protein in the urine. Later, the patient becomes lethargic, but behaves restlessly, severe pain deprives him of sleep. After 3-5 days, the victim develops characteristic skin rashes and the condition improves. Recovery occurs after 2-3 weeks, but weakness usually remains for more than a month. If help is not provided in time, death may occur. So in the Kherson region over the past 25 years - 500 people were bitten. Of these, 10 people died. After the mating season, the female karakurt kills and eats the male and begins to build cocoons. And in September, intense death of karakurts begins; by the end of October, all adult individuals die, only spiders in cocoons remain to overwinter.

Origin of the species and description

Photo: Karakurt spider

Karakurt belongs to the arthropod arachnids, is a representative of the order of spiders, the family of web spiders, classified in the genus black widows, a species of karakurt.

The exact period of origin of the ancient ancestors of modern spiders - arachnids - is quite difficult to establish, since they do not have a shell, and the chitinous layer is destroyed quite quickly. However, scientists and researchers still manage to occasionally discover such finds. Most often, the remains of the ancient ancestors of modern spiders were preserved in amber. The discovered findings made it possible not only to recreate the external image of the ancient ancestor of arthropods, but also to obtain entire pictures in the form of a frozen mating process, or weaving a web.

Video: Karakurt spider

Ancient amber finds allowed scientists to conclude that spiders already existed approximately 300 - 330 million years ago. On the territory of modern China, scientists have discovered fossils of ancient arthropods. In these finds, the shapes and body structure of insects were very clearly visible. It is in this area that the remains of the most ancient spider, Attercopus fimbriunguis, were discovered. The ancient representative of arthropods had small sizes, not exceeding five millimeters, and a long tail, which was about a fifth of the length of the body.

It was used by insects to secrete sticky threads. They were involuntarily released and used by ancient spiders to line burrows, wrap cocoons, and attract individuals of the opposite sex. Ancient arthropods of that time had a slightly different body structure. In addition to having a tail, which is absent in modern insects, they had an incompletely fused head and abdomen.

Presumably the first spiders appeared on Gondwana. With the formation of Pangea, they rapidly began to multiply and inhabited almost all parts of the Earth. Subsequent ice ages somewhat reduced the habitat areas of arachnids. These insects were characterized by fairly rapid spread and modification. At the beginning of the Carboniferous, they tended to lose the division of the cephalothorax and abdomen. Scientists say that the remains of spiders, which date back to 150-180 million years, allow us to conclude that the arthropods of that time were practically no different from modern spiders.

Black widows attack Russia. Video (00:03:13)

To combat karakurts, arachnologists - spider experts - recommend treating your garden plot with chemicals. It is noteworthy that the black widow does not attack people herself. She can bite if, for example, you step on her. The karakurt poison spreads throughout the body instantly. If you do not go to the hospital in time, death occurs within two days. At the moment of the bite, the victim does not feel pain; it occurs only after 10-15 minutes. Sharp pain appears in the lower back, abdomen, chest, breathing is impaired, and convulsions occur. With timely treatment, recovery occurs in 2-3 weeks. Karakurt is a fairly large spider, reaching 2 centimeters in length. The spider is black in color and has 13 red spots on its back. It is considered the most dangerous spider in Russia. Karakurts are rapidly spreading across dozens of regions of the country. The Volgograd region is now experiencing a real invasion. There are traditionally a lot of them in Crimea. Cases of bites have been recorded in the Urals, Saratov, Orenburg and Novosibirsk regions. According to experts, with such dynamics, the Moscow region is next in line. The rapid advance of the karakurt deep into Russia is alarming; the scale of the danger is impressive: the “kiss” of a black widow is 15 times more poisonous than the bite of a rattlesnake. In several regions of Russia, almost 20 people have suffered from poisonous spiders, six are in intensive care. The poisonous spider has been spotted not only in the south of the country, but also in Novosibirsk and Moscow, where the karakurt (the official name of the insect) is driven by the heat from its traditional habitats - the Central Asian steppes. By the way, they tried to settle in the Moscow region a couple of years ago. Fortunately, it hasn't worked out yet.

Appearance and features

Photo: Karakurt spider in Russia

These species of spiders have very pronounced sexual dimorphism. The female is significantly larger than the males. The average body size of one female individual is approximately 2-2.5 centimeters, male - 0.7-0.9 centimeters. The spider is quite easy to distinguish from other arthropods. The body and long limbs are black with red spots on the abdomen. In some arthropods they may have a white edge. They often disappear after reaching puberty, leaving the body a solid black color.

The arthropod has four pairs of long limbs located on both sides of the body. The longest are the first and last pairs. The two pairs of limbs that are located in the middle are shorter. They are covered with special hairs that allow them to easily approach a victim caught in the viscous spider threads. Spiders have a special gland that produces powerful poison. It is designed to paralyze and kill insects. Also, with its help, karakurts kill small steppe rodents, whose burrows they subsequently occupy.

Newborn small spiders are almost transparent. However, after the first molt, the body acquires a darker shade, and whitish circles appear on the abdomen, arranged in three rows. After each subsequent molt, the insect’s body becomes darker and the circles become red. The more often a spider molts, the faster it matures. The frequency and multiplicity of molting depends on a sufficient amount of food supply. Male individuals most often, after the sixth or seventh molt, stop feeding heavily and begin searching for a female to continue the race.

Interesting fact: Surprisingly, Karakurts have blue blood. This is due to the fact that it is not the scarlet hemoglobin that is responsible for the color of the blood, but hemocyanin, which gives the blood a blue tint.

The most poisonous spiders in the world TOP 10. Video (00:04:00)

Rating: The deadliest spiders in the world The most poisonous spider in the world, according to the Guinness Book of Records, is the “Brazilian wandering spider.” The spider got its name because it does not sit in one place and does not weave webs, but actively moves in search of food. Another extremely dangerous spider is the Black Widow, or in our language Karakurt, which can be found in the Caucasus and Crimea. I present to your attention the rating of the 10 most poisonous and dangerous spiders on planet Earth 10. Yellow spider Sak (Cheiracanthium Punctorium) 9. Fringed Ornamental Tarantula 8. Chinese tarantula Chinese Bird Spider 7. Mouse Spider 6. Brown or Chilean spider recluse Brown and Chilean Recluse Spider 5. Redback spider 4. Black widow (Karakurt) 3. Sydney funnel-web spider 2. Six-eyed sand spider. 1. Brazilian wandering spider

Advantages

The Cinderella incubator has an almost 100% hatchability rate. The chamber is designed for 70 eggs, but if you remove the mechanism with automatic reversal, then for 98 eggs, as can be seen in the photo. If you take eggs other than chicken, you can fit even more.

The device consumes 50 W. It is connected to a regular 220 W network. The instructions for Cinderella describe the process of connecting the device to a car battery if necessary.

The Cinderella incubator contains a device with automatic turning. During the day he can carefully turn the eggs ten times. The device comes with a special grill for 70 eggs, a thermometer, and detailed instructions for setting up all functions.

Foundation for a greenhouse

To build a greenhouse using stretch film, you do not need to build a foundation. For example, if you use wood to install the frame, then to fully strengthen the structure you will need to install a simple base made of ceramic bricks or wooden beams. If a frame made of propylene pipes is used, then good soil compaction will be sufficient.

For structures more than one and a half meters in height, it is best to use additional frame fastening so that gusts of wind do not blow away your greenhouse.

Assembly

The installation of the greenhouse begins with the installation of the frame. At the same time, they take into account what material it is made of. For heavy wood or metal, first assemble the ends, then proceed to the bottom trim. Then they move on to installing vertical supports and making the top trim.

The lightweight structure made of polypropylene arches is simply buried in the ground after preliminary compaction. For reliability, they make a strapping from below, laying out wooden blocks and attaching vertical supports to them with clamps or corners.

Wrapping the prepared frame with stretch film begins from the top. To begin with, make one turn in the horizontal direction, covering all support points. Then winding is done. The initial layer is laid without overlap. Then subsequent layers are laid from top to bottom, overlapping the previous one by a third of the width. This method retains the greatest thermal conductivity.

Determining sex in rabbits

Male genitals

Female genitals

It is quite difficult to determine the sex of rabbits by appearance. In this subtitle of the article we will tell you how to correctly determine the sex of an animal. To do this, take the rabbit with your left hand in the area where the cervical and thoracic vertebrae are located, and then turn it over with its belly up and with two fingers of your right hand (let it be the index and middle finger) pinch the tail at the very beginning. Then, with your thumb, slowly pull the skin in front of the rabbit's genitals (in the direction of its head). If you see a downward curved penis, you have an adult male in your hands, but if you see a hole with a tubercle in it, then the male is young. In females, the genitals look like an oblong slit, which narrows towards the tail.

Material calculations

In order to estimate the level of future costs, we will try to make an approximate calculation of the amount of materials for the construction of a standard version of a greenhouse made of stretch film.

First of all, for the frame structure you will need:

• For the manufacture of walls there are four corner beams 60x60x2500 mm, the same amount for piping along the lower and upper levels;
• For diagonal struts on the walls, you will need six pieces of 40x40x3000 mm slats;
• To make a hatch and a window, five pieces of timber 50x50x2000 mm, you can also make an entrance door from it;
• For the roof truss system, four triangles are made; in total, 16 slats of 40x40 mm, 300 cm long, are required.

The amount of stretch film must be calculated based on the total surface area of ​​the greenhouse, taking into account the roof slopes. In theory, the stretch coating should be laid with an overlap of at least 10% of the width of the film; in practice, stretch film is simply purchased with a reserve.

Standard tape for manual wrapping and packaging of goods has a width of 450-500 mm; one such roll contains 300 m of material or 120-150 m2. If you are making a regular greenhouse, one roll is enough, but if you plan to use a greenhouse made of stretch film in winter, then the number of layers will need to be increased at least three times, which means it is enough to purchase two reels.

Options and schemes for greenhouses made of stretch film

Despite the certain democratic nature of the material, stretch film requires compliance with certain rules for laying the cladding. In theory, it is possible to cover a greenhouse with stretch film if the frame is rounded or dome-shaped, if it occurs to someone to build a similar type of greenhouse.

But to keep the cladding on the rounded surface, you will have to make incredible efforts.

Therefore, in order to avoid unnecessary problems, it is recommended to build a greenhouse with your own hands from stretch film of a more traditional design, for example, a rectangular or square type. Moreover, the dimensions of the stretch film strip were planned and selected specifically for packaging in the form of boxes.

In the simplest case, a small greenhouse can be built on a flat roof in just a few hours of work.

You don’t have to worry about strength, the stretch film tightens and firmly holds the frame of the building

Essentially, these are several stakes or racks of timber driven into the ground at the corners of the greenhouse. Instead of a roof and floor, latticework made of wooden slats is laid. You can build such a greenhouse from stretch film in one visit to the dacha, and after the end of the season, the structure can be very easily disassembled and stored in a shed.

Harm from swimming beetles

By settling in artificial reservoirs, swimming beetles can cause serious harm to fish farms. Insects eat the fry, which sometimes leads to the destruction of an entire population of fish. To destroy a dangerous pest, the following control methods should be used:

1. You need to drain all the water from the pond and treat the bottom with slaked lime.
2. To increase water circulation, you can install a fountain in the pond. Beetles do not tolerate fast currents and will soon leave your property.
3. Breed crucian carp - natural enemies of swimming swimmers.

Which stretch film to choose for a greenhouse

You can often come across the opinion that for the manufacture of small greenhouse greenhouse buildings, the type and brand of stretch material is not particularly important. In fact, both PVC and polypropylene material will work for most small greenhouses.

Important! Film for food packaging, even in theory, cannot be considered as a covering for greenhouses. The first heavy rain will destroy the greenhouse; even reinforcement with adhesive tape will not save it.

If you plan to build a full-fledged greenhouse 3x4 meters, then it is best to choose EVA stretch film with a thickness of at least 20 microns. There are brands with a thickness of 30 microns; working with such stretch coatings is quite difficult, since you have to lay the film by hand, and this requires significant physical effort.

You must definitely pay attention to the thickness, since most stretch films sold have a characteristic of 17-20 microns.

Proper marten hunting video with husky

It is not always possible to see the good work of a hunter and his dog, which can be exemplary for all beginners.

This video contains footage of a hunt with a husky. One mature hunter goes into the snowy forest to hunt down a marten. After a certain time, his faithful assistant finds a trail that leads to a large and dry tree.

It becomes clear that the marten climbed into an empty tree trunk. Now we need to try to drive the animal out of there. The hunter takes an ax and begins to knock on the trunk, but nothing happens. The decision is made to cut down the tree.

Next, a cut is made in one place on the felled tree, which resembles a kind of pocket. The hunter thrusts a stick into it to drive the beast out, but this does not help.

The following frames are accompanied by cutting another pocket from the opposite side. Only after these actions does the marten jump out of the tree trunk and rush to run away.

Laika instantly rushes to grab her, but doesn’t have time. She climbs a tree and begins to rush around the branches. The hunters' first shot misses, but the second hits the target.

Additional Tips

To successfully breed rabbits, there are many factors to consider. For optimal mating, you need to follow simple recommendations:

• proper nutrition - no obesity when the pet is full;
• hygiene of the animal and its place of residence;
• checking the health of animals, including from a veterinarian;
• lack of sexual intercourse during molting;
• carrying out control matings to check the sexual maturity of both participants in the mating.

How to mate rabbits

For proper mating of rabbits, it is necessary to remember that the female must be placed in the cage with the male, and not vice versa. This is done because in a new environment the male may simply get scared and be inactive. Remove anything from the cage that might interfere with the rabbits' covering. For example, drinking bowls, feeders, etc. A female rabbit can be considered covered if, after the female, the male falls to the side with a characteristic squeak. He can remain in this position for several seconds. If the female's covering is questioned, it must be repeated. After mating, place the female rabbit in a specially prepared cage.

It also happens that the female rabbit does not accept the male well. If you have such female rabbits, then after four to five hours, the female rabbit can be placed again with this male. If the female rabbit does not accept the male well the second time, then he needs to be changed. After another five days, you need to carry out the so-called control mating. If your female rabbit is already pregnant, she will not let the male in. If during the control mating the male still covers the female rabbit, then after five days you will need to place her again with the male.

Important parameters

Wrapping with stretch film is an easy way to update your existing greenhouse. A ready-made frame made of any type of material will be suitable. However, special attention should be paid to the choice of film. If construction has to start from scratch, it is necessary to choose the type of structure, its dimensions, and even the type of foundation.

Base and materials

A foundation for such a greenhouse is not required. If the frame is heavy, for example, wooden, solid, then it is permissible to make a small base from timber or brick. In this way, rotting of the main supports can be prevented. If propylene tubes are used as a frame, you can get by with a standard seal of the selected area. If the walls are large and the height is more than one and a half meters, it is necessary to securely fasten the greenhouse frame to the ground. The film will not be elastic after stretching, so the wind will affect the entire area. If the soil allows, you can dig the supports deeply; a more reliable option is to strengthen them with a lower frame made of heavy materials.

When choosing stretch film, you should pay attention to the thickness, raw materials and barrier properties. You can compare several types according to the parameters indicated in the table:

The best option for a greenhouse would be films made of PVC or polypropylene. Kling materials are too thin; at least 5-7 layers are required for sufficient insulation, but light transmission in this case drops sharply. Polystyrene compounds are too inelastic; EVA films have better mechanical characteristics, but their cost is several times higher, so it is not recommended to use them for homemade greenhouses.

In Europe, PVC products are not used because they are considered toxic. But in some countries there is no such ban.

When working with film, it is necessary to take into account its type in order to avoid common mistakes. Polystyrene products have little stretch, while PVC compositions can extend 3-4 times. The recommended stretching rate is no more than three times. Thus, it is possible to maintain firmness, elasticity, strength and achieve a strong connection between layers of material. Thermal welding is not used: under the influence of temperature, stretch materials melt and shrink, and no fixing occurs. It is also unacceptable to pierce metal fasteners in free areas where there is no strong support around the perimeter. Any adhesives must be used carefully. Some chemical elements can literally “eat away” the film.

Design

An arc-shaped design is considered optimal. It can be assembled from vertical supports and film; nothing else is required. At the same time, you can achieve almost any height by choosing a frame of the required thickness. This form does not require the construction of a base or roof; if necessary, each individual element can be replaced.

When choosing the shape of a future greenhouse, it is necessary to take into account the level of snow load and the possible impact of condensation. If the heifer is year-round, stingrays are required. It is extremely difficult to construct a gable roof from film; the arc shape, in turn, will not allow snow to accumulate on top of the structure, so collapse is unlikely. Inside, condensation will flow down the walls, which is also desirable. The soil will thus be moistened and no drops will fall on the leaves.