Barn rat. Ways to control rodents

Pasyuk (gray barn rat) is the most unpleasant and common rodent. Every day, colonies of these pests cause irreparable damage agriculture, berry, forest plantings.

They can pose a danger to pets and human health, as they are carriers of serious diseases.

Gardeners need to be able to deal with them correctly and protect their territory from such unnecessary guests.

Description of the pasyuk rat

The animal belongs to the order of rodents and the genus of mammals. It is considered the largest rat that lives in nature in Russia.

The main characteristics of the animal: - it is a gray, ordinary rat. It has an elongated body 20-27 cm long, weighs 150-400 g, tail length 19-21 cm. The paws are pink, clawed, skeletal. barn rat has a wide muzzle and a light mustache. The ears are pointed with a pinkish tint. The fur color is grayish, close to agouti, and the belly is whitish. The border between the color of the barrels and the belly is clearly visible. The fur of young individuals is gray; with age, a reddish tint appears in it. Sometimes common black rats are found in nature. The hairs are quite coarse and have different lengths, guard hairs stand out - those that are more shiny and long.

Origin of the species

Scientists believe that this type rats appeared in eastern territory China. They were brought to Europe on merchant ships through sea communication between countries. The scientific name “Norwegian rat” was acquired in 1769 due to the mistake of the English biologist John Berkenhout, who made a rash conclusion that the rodents came to Denmark on industrial ships from Norway, although at that time they were not yet in that country.

Distribution and reproduction

In the most different corners These rodents can be found all over the world. They achieved wide distribution thanks to passive movement on merchant ships.

At the beginning of the 18th century, these rodents began to be found in every part of Europe, including Russia. Their habitat can be any part of the planet where there is water and food, as well as climatic conditions, favorable for survival.

The barn rat is very fertile. She reaches puberty at three months. At one year of age it can produce a litter of about 7-10 individuals. You can imagine how many offspring appear everywhere every year. Pasyuk is considered one of the most prolific rodents on the planet.

Lifestyle

Ordinary rats lead a crepuscular lifestyle. The activity of these individuals occurs from seven in the evening to eight in the morning, with a maximum peak at ten o’clock in the evening. They can crawl out of their shelters during the daytime if there is any need for this. They live in colonies or groups and quite aggressively protect their territory from strangers. They recognize members of their flock by smell.

In nature, shelters for them include stumps, snags, holes, and ruined nests. In urban environments, they most often live in garbage dumps, basements, landfills and sewers.

Nutrition

The diet consists of plant foods, fish and meat, grain, and any food waste. Many animals can envy the viability and resilience of pasyuks. They have high adaptive capabilities, have mental flexibility, swim and dive well, jump up to 80 cm, and reach speeds of up to 10-12 km/h.

Harm

Barn rats cause a lot of damage in households. Rodents drag away and eat bean crops from barns, damage storage containers, boxes, boxes, bags, and gnaw fruits and vegetables. On out-of-town garden plots Pests prefer to eat vegetables, berries, fruits, roots of plants and garden flowers.

Gray rats gnaw through the walls of barns and buildings, damage furniture and wires. After their teeth, not only does it become unsightly appearance living space, damage to the wiring can lead to short circuits and fires.

The rat poses a danger not only to human health. Cases often arise when rodents attack domestic animals.

Ways to control rodents

The most effective and the best means to fight rats to destroy them.

Toxic substances are sold in specialized stores large number. Types of poisons can be divided into strong and weak. The first category includes phosphate and It is a fast-acting poison. When it enters the stomach, it reacts with hydrochloric acid, which produces hydrogen phosphide, which stops breathing. To kill a rat, a three percent concentration of poison is suitable. The advantage is that if the poisoned rat is eaten by other animals, it will not cause poisoning in them.

Long-acting poisons are more suitable for controlling small rodents. It will take quite a long time for a sufficient amount of the substance to accumulate in the body to destroy the animal. The gray rat's body is resistant to poison, and this can cause addiction to it, so the type of substance will have to be changed from time to time.

How is poison used?

The main methods of use include:

Poisons with which delicacies are impregnated: bread, cheese, pieces of meat, grain. This method is the most effective and widespread.
Chemicals are also dissolved in water, milk - liquid baits.
Powdered chemicals. They pollinate the exit from the hole and other places where gray rats can be seen
Gaseous chemicals. They can be used to irrigate burrows, but this method is used with caution, especially in rooms where people live.

Mechanical traps

You should not charge the mousetrap at full power; the rat needs to get used to the left treat. In this case, she will not suspect that the trap will soon work and slam shut.

Placing mousetraps is the most in a simple way, however unreliable. A barn rat is larger than a vole, so a simple standard mousetrap will not work for it. In addition, after catching a rodent and successfully escaping, 1/2 of the rats will not come back even for the most exquisite bait.

Ultrasonic repellers

This method is quite effective. Ultrasonic waves negatively affect the psyche of rodents, which forces them to leave the territory they previously inhabited. But to achieve a good result, the device must work on an ongoing basis. In addition, when purchasing a device, it is necessary to take into account the size of the area it will be used in and the duration of the emitted wave. For sheds and barns, a standard universal repeller is suitable. If the device has to be installed on the site larger size, you need to purchase several devices.

Path closure

In order to get rid of rats in a barn or house, you can use another good method - blocking the paths. To do this, you need to calculate all the passages and paths along which the rat makes its way into the house and sprinkle calcium chloride near them; these animals cannot tolerate it. Rat loopholes and passages are also covered with cement and crushed glass; it will be extremely difficult to gnaw through such a wall.

If there is a rat, all means are good to fight it. To reach effective result, you shouldn’t settle on any particular method, but rather combine them or change them periodically. And you shouldn’t delay exterminating rats, so as not to aggravate the situation.

synonyms

Mus caraco Pallas, 1779
Mus caspius Oken, 1816
Mus decumanoides Hodgson, 1841
Mus decumanus Pallas, 1779
Mus griseipectus Milne-Edwards, 1872
Mus hibernicus Thompson, 1837
Mus humiliatus Milne-Edwards, 1868
Mus javanus Hermann, 1804
Mus magnirostris Mearns, 1905
Mus maniculatus Wagner, 1848
Mus maurus Waterhouse, 1837
Mus ouangthomae Milne-Edwards, 1871
Mus plumbeus Milne-Edwards, 1874
Mus surmolottus Severinus, 1779
Rattus norvegicus albus Hatai, 1907
Mus sylvaticus discolor Noack, 1918
Mus decumanus hybridus Bechstein, 1800
Rattus humiliatus insolatus A. B. Howell, 1927
Mus decumanus major Hoffmann, 1887
Rattus norvegicus otomoi Yamada, 1930
Mus norvegicus praestans Trouessart, 1904
Rattus norvegicus primarius Kastschenko, 1912
Epimys norvegicus socer Miller, 1914
Rattus humiliatus sowerbyi A. B. Howell, 1928

Area Security status

Taxonomy
on Wikispecies

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Gray rat, or Pasyuk(lat. Rattus norvegicus), is a mammal of the genus rats of the rodent order. Synanthropic, cosmopolitan species. Scientific name Rattus norvegicus- Norwegian rat - this species was received by misunderstanding: the English naturalist John Berkenhout, who gave it, believed that rats came to England on Norwegian ships in 1728, although in fact there were still gray rats in Norway at that time there was none, and they may have migrated from Denmark.

Appearance

Spreading

Currently, gray rats are found on all continents of the world. Only the polar and subpolar regions, Antarctica, are completely free from them; V tropical zone distributed mosaically. The resettlement of rats continues to this day; so, until the 1950s. they were not found in Alberta (Canada) and are now extremely rare there, with the exception of rats imported for research purposes.

The gray rat's homeland is believed to be in East Asia. During the Pleistocene, cooling and advancing glaciers isolated the rat population in eastern what is now China. From the east and south, their habitat was limited by the seas, from the southeast - by the mountain tropical forests of Indochina, in the west - by the desert plateaus of Central Asia, and in the north - by the vast glaciers of Siberia. Due to these natural barriers, the spread of gray rats began only in the Holocene with the onset of warming. Their natural settlement along river valleys proceeded very slowly, and for 13,000 years rats did not penetrate north of Altai, Transbaikalia and southern Primorye.

Gray rats managed to conquer the world thanks to passive settlement, mainly on sea vessels. Thus, on the Hindustan Peninsula they appeared no earlier than the 1st century. BC e. From there in the 7th century. were brought by Arab sailors to the ports of the Persian Gulf, Red Sea, and East Africa. But only at the turn of the 16th century, when maritime trade between Europe and India began, did the rapid migration of rats to more favorable climatic and economic conditions in Europe begin. By 1800, gray rats were already found in every European country; appeared in the New World in the 1770s. From Europe they were also introduced to the coast of Africa, Australia and New Zealand. Currently, Pasyuk are the dominant representative of the rat genus in Europe and North America.

Settlement in Russia and the former USSR

Subspecies

Within a view Rattus norvegicus There are 2 main lines:

East Asian ( Rattus norvegicus caraco),
Indian ( Rattus norvegicus norvegicus).

Representatives of the first are the aborigines of Eastern China, naturally populated the surrounding areas. They are distinguished by their smaller size, relatively short tail (70% of body length), brownish color and its pronounced seasonal change. They live in East Asia: Transbaikalia, Far East, o. Sakhalin, northeastern Mongolia, Central and Eastern China, the Korean Peninsula, Hokkaido and Honshu islands (Japan). All other territories are populated predominantly by representatives of the second line, which was formed from coastal populations R.n. caraco about 2000 years ago.

Habitats

The gray rat is originally a semi-aquatic species, naturally living along the banks of various reservoirs. Due to the tendency to synanthropy, omnivorousness, high research activity, quick learner and high fertility, it has adapted to life in anthropogenic landscapes and directly in human buildings. Currently, based on the nature of their connection with humans, there are 3 ecological zones where rats live:

northern zone where the rats all year round live in human buildings;
the middle (transitional) zone, where in the summer they populate natural biotopes, including littoral ones, and return to buildings in the winter. Only a fraction of the rats sometimes remain to spend the winter in natural conditions; Only settlements on large urban landfills are year-round. In the European part of the range, the southern border of this zone runs approximately along the Kharkov-Saratov-Nizhny Novgorod line, beyond the Urals - along 50° N. sh.;
southern zone, where a significant part of the population lives outside buildings all year round. On the territory of Russia these are the lower reaches of the Volga and Don, as well as the original habitat in the south of the Far East and on the island. Sakhalin, where rats constantly live away from housing, being a natural component of near-water ecosystems.

Gray rats prefer to inhabit the gently sloping banks of reservoirs, with good protective conditions - dense vegetation, voids in the soil, etc. Under natural conditions, they dig fairly simple holes 2-5 m long and up to 50-80 cm deep. Inside the holes, nesting chambers with a diameter of about 30 cm. As building materials for the nest they use any available materials: grass, leaves, feathers and wool, rags and paper. In the lower reaches of rivers during flood periods they live in hollows or build simple nests from branches in trees. In anthropogenic landscapes they inhabit the banks of artificial reservoirs, vegetable gardens, orchards and parks, wastelands, recreational areas (for example, beaches), landfills, sewers, and the edges of “filtration fields.” Required condition is the proximity of water. In cities, they sometimes rise up to 8-9 floors in buildings, but they prefer to settle in basements and on the lower floors of residential and warehouse buildings, where food supplies are available and household waste provides them with food supply. Penetrate into mine shafts, tunnels and subway shafts, vehicles. In the mountains (Greater Caucasus) they are found up to 2400 m above sea level in dwellings and up to 1400 m above sea level in vegetable gardens.

Settlement routes

Gray rats settled partly on their own, along waterways, but more often with human assistance. They move mainly by various river and sea transport; other modes of transport (railway, road transport, airplanes) - much less often. The exception is subways [ ], where rats willingly settle and live in huge numbers. Entering the city for the first time, they settle with high speed. Thus, at the beginning of the 21st century, the population of rats in Barnaul was accurately traced [ ]: in the year of their appearance they were found only in the buildings of the pier, in the 2nd year they occupied blocks near the pier, in the 3rd year they reached the city center, in the 4th year they occupied the entire city, and in the 5th year they began to populate suburban villages. The population of gray rats in Tashkent proceeded at approximately the same speed. Rats enter buildings through open entrance doors(especially in the dark) and through the ventilation openings of the basement and first floors.

Lifestyle

Activity is predominantly crepuscular and nocturnal. When settling near a person, the pasyuk easily adapts to his activity, changing its daily rhythm. Leads both solitary and group, and in nature, a colonial lifestyle. There can be several hundred individuals in a colony; in Buddhist temples, where they are constantly fed, there can be even 2000. Within the group, there are complex hierarchical relationships among the males. The group owns a territory of up to 2000 m2, which it marks with scent marks and protects from the invasion of strangers. When there is enough food, city rats often do not move further than 20 m from their nest. The routes along which rats move are usually constant and run along walls, baseboards, and pipes. They easily remember the path even through complex systems sewerage. Pasyuk is very smart - it is no coincidence that the Polish zoologist Miroslav Gushch called rats “the intellectuals of the animal world.”

Gray rats lack spatial conservatism, and they willingly settle in new territories. These are active animals with extraordinary physical characteristics. If necessary, the rat can reach speeds of up to 10 km/h, overcoming barriers up to 80 cm high while moving (they can jump up to 1 meter from a standstill). Every day a rat runs from 8 to 17 km. They swim well (can stay in water for up to 72 hours) and dive, staying in the water for a long time and even catching prey there. Rats have poor vision. The viewing angle is only 16° and provides a small coverage of space; this deficiency is compensated by frequent rotation of the head. Rats perceive the bluish-green part of the light spectrum and generally see everything in gray color. Red color means complete darkness for them. The sense of smell is well developed, but at short distances. They hear sounds with a frequency of up to 40 kHz (humans - up to 20 kHz), react sensitively to rustling noises, but do not distinguish pure tones. They can settle and successfully reproduce both in refrigerators with constant low temperatures and in boiler rooms with high temperature. Very easy to withstand high level radiation - up to 300 roentgens / hour.

Nutrition

The gray rat differs from most rodents in its increased animal-eating - it certainly needs animal proteins in its diet. In nature, among animal foods, fish and amphibians, as well as mollusks, come first; in the Far East, pasyuks actively hunt small rodents and insectivores, and destroy ground nests of birds. Rats living along the shores of ice-free seas feed on marine waste all year round. Plant foods include seeds, grains, and succulent parts of plants. Near a person, pasyuki feed on everything available food products, as well as waste, livestock and poultry feed; Fecal feeding is not uncommon. Stocks are made quite rarely.

Each rat consumes 20-25 g of food per day, eating 7-10 kg of food per year. Gray rats suffer from starvation hard and die without food after 3-4 days. They die even faster without water. Each rat drinks 30-35 ml of water per day; Eating wet food reduces the need for water to 5-10 ml per day. Experimentally, it was found that rats can exist normally when consuming food containing more than 65% moisture. If the moisture content of the feed is 45%, the rats die after 26 days, and at 14% - after 4-5.

Reproduction and lifespan

The reproductive potential of the gray rat is extremely high. In nature, rats breed mainly in the warm season; In heated rooms, reproduction can continue all year round. In the first case, there are usually 2-3 broods, in the second - up to 8 per year; the number of cubs ranges from 1 to 20, with an average of 8-10. Within 18 hours after giving birth, females again enter estrus and mate again. There are 2 peaks: spring and autumn. The abundance of animal food increases the intensity of reproduction; it also increases after incomplete deratization, compensating for population losses.

Gray, or barn, rat, pasyuk. Body length up to 250 mm, tail length up to 120 mm (always shorter than the body, on average about 80% of its length). The muzzle is wide and blunt. The auricle is short and dense, oval in shape, covered with hair more densely than that of a black rat; the entire ear, extended forward and attached to the side of the muzzle, does not reach the eye. The notch at the base of the ear is narrow, always in the form of an acute angle. The tail is always shorter than the body, sometimes almost naked, sometimes covered with short and sparse hairs. The number of scaly rings of the tail, as a rule, does not exceed 200 (146-177-200).

The foot is relatively long. The calluses on the back and front feet are relatively small. The external lower callus of the hind foot is two to three times smaller than the external upper callus and is often reduced. At the base of the toes of the hind foot there are always small folds of skin stretched between the toes. The gray rat's fur is generally coarser than that of the black and Turkestan rats. The number of nipples is usually from 10 to 12 (depending on geographical races). The head of the penis is cylindrical, its sides are parallel or slightly convex. On the side of the head, below the midline, there is a deep groove on both sides of the distal part. The annular fold weakly protrudes from the opening of the head.

The color of the upperparts ranges from relatively light, reddish-brown to darker, dirty buffy-brown. Among the bulk of hair dyed in this way, individual, harder and longer guard hairs with a metallic sheen stand out. Ventral side with dark hair bases.

The skull of the gray rat is angular, with well-developed ridges, with a slight sharpening of the nasal part; the dorsal profile line reaches its greatest height above the molars. The masseter plate of the maxillary bone is large, with a strongly protruding upper angle and an anterior edge inclined backwards. The infraorbital foramina are wide. The plate of the lower branch of the zygomatic process of the maxillary bone with a strongly protruding upper angle; in accordance with this, the entire front edge of this plate usually runs obliquely; the width of this plate, measured from its most prominent point leading edge, to its posterior edge, makes up 75-98% of the length of the upper row of molars. The outer flat side of the zygomatic process of the maxillary bone with a longitudinal depression (the outer edge is slightly raised); The greatest spacing of the cheekbones is located approximately in their last third, occasionally in the middle. The ratio of the width between the cheekbones to the condylobasal length of the skull is 0.52 (average). The parietal bones in adult individuals are not convex and are located approximately in the same plane as the frontal and interparietal; they are bordered on the sides by almost straight or slightly curved ridges running parallel or slightly diverging in a posterior direction. The tympanic chambers are less swollen than those of the black rat, their anterior angles are elongated into long tubes. The main occipital bone is wide and the tympanic chambers are not close together on their inner sides. (The length of the suture between the main sphenoid and main occipital bones is 20-30% of the auditory width of the skull). The length of the incisive foramina in relation to the condylobasal length of the skull is 16.8 (average).

Among pasyuks, as well as house mice, individual deformities, curvature of the bones of the skeleton and skull, and caries of teeth (mainly molars) are more common than among our other rodents. The latter is especially characteristic. Very often, pasyuki suffer from all kinds of skin diseases that cause hair loss. Individual skin lesions, common in such a pugnacious animal as this rat, constantly grow into purulent ulcers.

Spreading. All over the globe, except for polar countries and deserts. In the USSR it is absent in most of the central and Eastern Siberia(except for some ports of Kamchatka and islands of the Far Eastern seas) and in the deserts of Central Asia and Southern Kazakhstan; lives in Tashkent, apparently “entrenched” in some populated areas to the south of it (Ursatievskaya station, etc.), as well as in the northern and east coasts Caspian Sea. In the USSR, it apparently appeared in the main part of its range no earlier than the 16th–17th centuries, spreading from the west; reliable paleontological data on the existence of this species in the south of the European part of the USSR in prehistoric times There is no Holocene. However, in Transbaikalia, in southern regions Far East, and perhaps in the ranges of Siberia it is not a recent newcomer, but belongs to the number of native species of the fauna of Southeast Asia. Its remains have been known here since the late Pleistocene (China). In space southern Siberia from the Ural ridge to Lake Baikal appeared only at the beginning of this century, probably simultaneously with the construction of the Trans-Siberian railway, and the northern border, unlike the southern one, is not finally established here.

Biology and economic importance. The main means of passive settlement of Pasyuk are various types transport, mainly water and to a lesser extent railway. Active settlement in the warm season occurs along river valleys, along roads and railway tracks, and in urban conditions - along sewerage and other underground structures. Percentage of pasyuks moving out of human buildings in surrounding nature, is very small, and in winter all the evicted rats return to the buildings. IN rural areas Rats are especially willing to stay in railway warehouses, grain warehouses and mills. In summer they move to the outskirts of cities. By its nature, the pasyuk is an angry, quarrelsome animal; in captivity, it is almost never tamed, constantly quarrels and fights with its own kind, and rats caught in the wild are usually covered with sores from frequent bites of each other.

Based on the type of connection with humans within the range, ecological zones can be distinguished (the same as for the house mouse):
1) northern, where rats live all year round in human dwellings, mainly in populated areas located in river valleys, or large cities;
2) the middle, or transitional, zone, where in the summer some of the animals inhabit natural biotopes and return to buildings in the winter; only a part of the individuals and not every year remain here to spend the winter in wildlife, and long-term year-round existence of any significant part of the population is impossible here; however, during the period of hostilities, “wild rats” from among those living in the destroyed settlements were observed in the north-west of the RSFSR for a number of years; the southern border of this intermediate zone runs in the European part of the USSR approximately along the line Kharkov, Saratov, Gorky;
3) the southern zone, where a significant part of the population, especially those inhabiting the lower reaches of large rivers: the Volga, Don, Dniester, Prut and Danube, as well as the swamps of Transcaucasia, lives outside human habitations all year round; This also includes part of the range inhabited by the Far Eastern Pasyuk-Karako, which constantly lives (especially in the southern regions of the Far East) far from housing, along the banks of rivers, irrigation canals, among swampy reed thickets. European pasyuki also adhere to these same natural biotopes when they move out of buildings in the summer.

The gray rat is also found in vegetable gardens, vacant lots, gardens and parks, in grain fields and in stacks, where it occupies the “lower floors.” In urban conditions, it settles mainly in basements and on the lower floors of residential and warehouse buildings, where the nature of the storage of food supplies or waste provides a sufficient food supply. If available, it can even live in refrigerators with a constant temperature below -10°. Under natural conditions, it digs holes, usually quite simple; in the lower reaches of rivers during flood periods it lives in hollows or makes external nests in trees from branches.

A rat, encountered by a person and deprived of the opportunity to escape, often viciously attacks him, jumping up and trying to bite. In the wild, the pasyuk is very careful and it is not easy to catch it, especially an old animal, in a trap. Pasyuk breeding is very intensive and due to life in protected shelters, the number of litters per year can be very large.

In rural areas and on the outskirts of urban areas, the gray rat feeds mainly on garbage; Fecal feeding is also common. In natural conditions, animal food plays a significant role, with fish in the first place, and among invertebrates - mollusks; The Far Eastern pasyuk actively attacks small mouse-like rodents. Feeds on grain in the fields.

It reproduces most of the year, most intensively in the spring and summer. An adult female gives birth to up to 3 litters, with an average of 7 cubs each (from 1 to 15). Young rats at the age of 3-4 months become capable of reproduction.

The harm caused by the gray rat to humans is twofold. On the one hand, it directly destroys food (even young birds in poultry houses) or contaminates them with its fecal matter. However, pasyuk is especially harmful by gnawing on objects; Soft (and hard) containers suffer from this, as a result of which the amount of food lost through chewed packaging can be significant, many times greater than what the rat directly eats. Having settled in warehouses of textile goods, leather and especially fur, rats cause especially noticeable harm, since even minor damage to fabrics in bales and cuts discards tens of meters, and damage to leather and fur forces entire skins to be thrown out or converted into inferior grades. Extensive damage caused by rats in candy factories, especially in their most valuable departments - chocolate, has been described abroad. The strength of rats' incisors can be evidenced by the fact that they gnaw through the lead sheaths of telephone cables; In America, cases of accidents caused by short circuits due to rats gnawing wires in factories and electrical installations have been described.

The gray rat is of paramount epidemiological importance. Natural carrier of pathogens of plague, tularemia, several forms of tick-borne typhus fevers, leptospirosis diseases, erysipelas,