Methods of relative accounting of game animals. Novikov G.A. Field studies of the ecology of terrestrial vertebrates. Quantitative census of terrestrial vertebrates. Quantitative census of mammals. General instructions. Accounting for mouse-like mammals Methods for

Modern hunting cannot exist without taking into account the objects on which it is built. Therefore, recording animals that are hunted is an integral part of the activities of all hunting farms, a reliable prerequisite for the rational use and protection of animals. The accounting provides for the annual identification of existing stocks of animals in the lands and the determination on this basis of acceptable norms for their removal by hunters without harming reproduction.

18.1. Forms of organization of accounting work and methods of accounting for game animals

In our country, the organization of accounting work related to determining the number of game animals is carried out by a specially authorized state body - it was organized to ensure operational state control over the state of hunting resources in the Russian Federation by streamlining and bringing into a unified system the work on accounting of the state hunting fund, improving the methodological level and improvement of the organization of registration of game animals.

Counts of game animals on the territory of Russia should be carried out using uniform methods. Before the development and approval of a unified set of accounting methods for all types of hunting resources, and this is a serious long-term work, in the practice of hunting, accounting work for a number of species is carried out in accordance with the scientific and methodological recommendations of game management institutions, scientists and hunting specialists.

According to the Regulations on the State Service for Registration of Hunting Resources, records of game animals in designated hunting areas are carried out by hunting users and at the expense of these organizations.

Counts of game animals are carried out by district game managers, game wardens of the hunting supervision service, game wardens of commercial and sporting farms, game wardens of hunting farms; Qualified professional hunters are involved in the census. In the districts, the organization of registration work and the collection of registration material is carried out by the district game manager. In state fishing farms and hunting farms of hunter societies, the organization of accounting work is carried out by the game manager of the farm.

Ground work in the areas is carried out by census takers, including qualified professional hunters. The district game warden provides census workers with forms and brief instructions for conducting censuses, provides oral instructions on methods, sets deadlines for carrying out work and submitting completed registration forms.

Methods for recording game animals and forms of organizing accounting work are extremely diverse (Table 18.1).

Table 18.1

Methods for field census of the number of game animals (according to V.A. Kuzyakin, 1979)

Animal detection methods	Relative accounting methods	Absolute accounting methods
		Solid	Selective
			On trial plots	Tape	Combined
					Linear	Other combined
Visual: ground aerial surveys
Following activities:
Footprints in the snow Defecation Mainly by ear with the help of a dog Accounting for catch by boats

Note. The numbers indicate the following accounting methods: 1 – detection of birds and animals on routes; 2 – counts of waterfowl and woodcock at dawn; 3 – recording of animals in places of concentration (at watering places, salt licks, crossings, etc.); 4 – route counting of animals based on tracks in the snow; 5 – recording of defecation of ungulates, hares, and upland game; 6 – counting of upland game by holes; 7 – accounting of various animal species according to the frequency of occurrence of other traces of vital activity: gnaws, flutters, feathers, scraps of wool, etc.; 8 – recording of capercaillie and black grouse at leks; 9 – counting of deer and elk during the roar; 10 – counting of swamp and field game by votes from one point; 11 – accounting of squirrels and hares according to the time spent by the dog searching for one animal; 12 – trap-day method for counting small animals; 13 – aerial photography of herds of ungulates (reindeer, etc.); 14 – aerial photography of waterfowl in aggregations (wintering areas); 15 – counting of beavers by settlement; 16 – recording of arctic fox, fox, badger in burrows; 17 – counting semi-aquatic mammals (otters, minks, muskrats, beavers) in burrows with the help of a dog; 18 – mapping of individual areas of broods and single individuals of upland, field and swamp game; recording of waterfowl in individual water bodies; 19 – aerial survey of ungulates and large predators at large sample sites; 20 – mapping of individual and group areas of animals based on tracks in the snow (sight and salary with internal routes, usually with repetitions); 21 – frame with tracking; 22 – salary with run; 23 – accounting of ungulates, upland game by defecation on small sample sites; 24 – counting foxes, arctic foxes, badgers in burrows on large sites; 25 – mapping of individual areas of hibernating animals (bear, badger); 26 – detection with the help of a dog and mapping of all squirrels, hibernating animals and game birds on test plots; 27 – complete shooting of animals (squirrels, martens, sable) on a naturally isolated test site in a short time; 28 – recording of upland, field, and swamp game on tapes of constant or variable width; 29 – route aerial survey of ungulates and large predators; 30 – accounting of ungulates and upland game by excrement; 31 – counting of upland game by holes; 32 – counting hazel grouse with decoy and white partridge by voice; 33 – route surveys of squirrels and upland game with a dog; 34 – accounting of animals with registration of the number of crossings of daily tracks along the route and the use of daily tracks; 35 – recording of animals with registration of the number of individuals whose tracks crossed the route, and using the diameter of the animals’ daily range; 36 – relative accounting of animals by tracks in combination with any method of absolute accounting; 37 – relative counting of birds by holes and tracks in combination with any absolute counting method; 38 – relative accounting of squirrels and hares by the time one animal is spent by a dog in combination with any method of absolute accounting of these species; 39 – recording of animal kills at trial sites and relative recording of traces of activity (in the snow, etc. ) before and after fishing.

Methods for recording game animals and forms of organization are divided according to the following criteria:

according to the territory covered– censuses over large areas, censuses in limited areas (districts, individual farms);

by accounting objects– species-specific counts (counts of one species of animal), complex counts (counts of several species simultaneously on the same routes using the same methods);

on the use of transport equipment– aerial surveys, ground surveys (on foot, automobile, etc.);

by the nature of accounting– field (direct) censuses, questionnaire surveys (based on the methodology of field surveys; based on an eye assessment of the abundance of animals and trends in its changes; expert assessment by highly qualified census takers);

by the method of extrapolation of sample accounting data– the division can be carried out according to the land to which the data applies, for example: forest, field, total area, types of land, detours, farms, landscapes, tracts, natural areas, etc.;

by methods of detecting animals– visually of the animals themselves, by traces of their activity (footprints in the snow; defecation; shelters; others), by ear, with the help of a dog, with the help of self-catchers.

The results of all types of censuses are processed using variation statistics methods to determine the statistical error of the counts, establish their accuracy and calculate the maximum possible statistical error.

Based on the nature of the obtained mathematical parameters, the following methods are distinguished:

relative accounting(as a result, relative indicators are obtained - the abundance of animals, suitable for comparison across different recording sites, years, seasons, hours of the day, etc. Examples of such indicators: the number of animals encountered per day of routes along the land; the number of tracks per unit length of the route; average volume of catch per hunter per unit of time, etc.);

absolute accounting(allow you to calculate the total number of animals in a certain territory); the latter are divided into continuous (the territory is covered entirely by the census) and selective censuses (the census is carried out over a limited area, and then the data from this census are extrapolated to much larger territories); sample counts are divided into tape(recording on route strips, when the trial area is extended along the route, and its width is disproportionately less than its length), surveys on trial plots(the trial area is compact, and if it is rectangular, then the sides of this rectangle are commensurate with each other) and combined(combines two or more accounting methods or methods of collecting accounting material).

Accounting work has a seasonal aspect. In accordance with seasonality, guidelines for conducting censuses are also being developed. Thus, the Methodological Instructions for organizing, conducting and processing data on winter route census of game animals in the RSFSR (TsNIL Glavokhoty, 1990) determine the methodology for conducting route census of animals and birds in the winter. Methodological guidelines for recording the number of game animals in the forest fund of the Russian Federation (Rosgiproles, 1997) consider the specifics of conducting censuses in different seasons of the year.

Novikov G.A.
"Field research of ecology
terrestrial vertebrates"
(ed. "Soviet Science" 1949)

Chapter IV
Quantitative census of terrestrial vertebrates

Quantitative census of mammals

General instructions

Determination of the number of mammals is carried out in three main ways:

1) Counting animals through direct observations on routes, sample sites or aggregation sites;
2) Following the tracks;
3) By catching.

Depending on the ecology of the species, one or another technique is used. Below we will look at the most common and practical ways to count the most important groups of mammals, starting with mouse-like rodents and shrews.

Accounting for mouse-like mammals

Establishing even the relative abundance of mouse-like mammals (small rodents and shrews) is fraught with significant difficulties, because almost all of them are burrowers, many are nocturnal, and therefore the possibilities of counting through direct observations are very limited, and often completely absent. This forces one to resort to all sorts of, sometimes very labor-intensive, auxiliary techniques (catching with traps, digging and pouring out of holes, etc.).

The ecological characteristics of small animals and the nature of their habitats determine the preferential development of relative accounting. Some zoologists (Yurgenson and others) generally believe that an absolute count of mouse-like rodents (at least in the forest) is impossible. However, they are wrong; continuous counting is possible, but it is only associated with great difficulty and therefore has no prospects for mass application. Absolute accounting in the forest is especially difficult.

Depending on the task and the adopted methodology, quantitative accounting is carried out either on routes, or on sites, or, finally, without taking into account the territory. The selection of test routes and sites for counting rodents is subject to the same requirements as for birds - they must represent the most typical areas, both in terms of habitat conditions and the population of animals. The last circumstance is especially important in this case, since many species are distributed extremely unevenly, forming dense colonies in some places, and completely absent in others. Because of this, if the sites are located incorrectly, their number is insufficient or their area is small, major miscalculations are possible. The sites should not be less than 0.25 hectares, preferably 1 hectare or even more. An elongated rectangular shape is preferable to a square one, as it allows you to more fully cover various conditions. In some cases (see below) round platforms are used.

To obtain reliable information about the density of rodents, the area of ​​the recorded territory should relate to the total area of ​​a given biotope or area as a whole, as approximately 1: 100 and up to 1: 500 (Obolensky, 1931).

As a result of surveys at the sites, in addition to data on the numerical ratio of species in a given biotope, we obtain data on the population density of small mammals per unit area. Under homogeneous conditions and uniform distribution of animals throughout the territory, it is quite sufficient to establish the number of individuals per 1 hectare of a typical area. But if the landscape is mosaic, with a rapid and variegated change in soil-orographic and phytocenotic conditions, then it is more correct to use the concept of “united hectare” introduced by Yu. M. Rall (1936). This concept takes into account the percentage of different biotopes in nature and the number of rodents in each of these biotopes. “Let’s imagine,” writes Rall, “that the area under study contains three main stations A, B, C. Based on comprehensive survey sites (i.e., laid down to record not just one, but all types of small rodents. G.N.) the density of any type of rodent per 1 hectare in these stations is equal to a, b, c, respectively. Of 100% of this area in nature, stations are occupied by: A - 40%, B - 10% and C - 50%. If on an abstract combined hectare (i.e., a hectare that includes three stations) we take the density of rodents according to the ratios of the stations themselves, then we get a density on the combined hectare P, equal in our example (after reduction to a common denominator):

P= 4a +B +5c / 10

Thus, we establish abundance per unit area, taking into account the mosaic distribution of conditions and animals in the habitat, as opposed to the total high and low densities that are usually used in ecological studies. From this point of view, the use of the concept of a combined hectare gives all calculations incomparably greater specificity and reality and should be widely used not only when processing census results at sites, but also on routes, where changes in living conditions should also always be noted.

Typically, quantitative censuses of small mammals cover all species at once, despite the ecological differences between them. Rall proposes to call this method complex, as opposed to specific. However, in a number of cases, when it is necessary to study species with specific behavioral characteristics that are not amenable to standard accounting methods (for example, lemmings, steppe pieds, etc.), then they are taken into account specifically.

The most common and well-established method of relative quantitative counting of small mammals is counting using ordinary crushers, developed by V. N. Shnitnikov (1929), P. B. Yurgenson (1934) and A. N. Formozov (1937). In its modern form, this technique boils down to the following: in the place designated for the census, 20 crushers are placed in a straight line, 5 m apart from each other.

The crushers are placed, as in collecting, under shelters. The standard bait is crusts of black rye bread (preferably with butter), cut into cubes 1-2 cm in diameter. The registration lasts 5 days.

Inspection is carried out once a day - in the morning. Days during which it rained all the time or only at night, as well as especially cold or windy nights, are excluded from the total count as obviously unprofitable.

In practice, this is determined by the complete absence of production on all transects.

If the animal is not caught, but the trap is clearly released by him (the bait is chewed, excrement remains), then this one is also equal to the caught specimen and is taken into account in the overall results. To avoid such cases, the traps need to be guarded as sensitively as possible, but not so much that they slam shut from the wind, a fallen leaf, etc. from extraneous light touches. The bait should always be fresh and be sure to be replaced after rain or heavy dew; It is advisable to renew the oil daily.

Since the accounting results largely depend on the operation of the presses, the greatest attention should be paid to their placement and alertness.

The census results are updated as the number of trap days increases. Jurgenson believes that in order to fully characterize the number of mice in any forest biotope, it is necessary to lay 20 tape samples with a total number of trap-days equal to 1000.

The results of counting with crushers on a tape sample are expressed by two types of indicators:

1) the number of animals caught in 100 trap-days (harvest rate indicator),
2) the number of all and individual species per 0.1 hectares (sample area) and per 1 hectare.

Accounting with crushers has a number of undeniable advantages, which have ensured its widespread use in various types of research. The advantages of the technique include the following:

1) The technique is simple, does not require complex equipment, or a lot of labor and money.
2) Using crushers with standard bait you can catch almost all types of mouse-like mammals, including shrews.
3) Accounting provides quite satisfactory indicators for monitoring population dynamics and comparative assessment of the population of different biotopes.
4) The technique is characterized by significant efficiency, providing fairly massive data in a short period of time (with the help of 200 traps, 1 person in 5 days can obtain 1000 trap-days, which is quite enough to characterize the biotope).
5) A 100 m long strip sample provides data on the relative density of the animal population per unit area and is a good representation of average conditions.
6) Accounting is applicable both in open landscapes and in forests, and not only in summer, but also in winter.
7) Due to the simplicity and simplicity of the equipment, the technique facilitates standardization and, thanks to this, obtaining comparable data.
8) All caught animals can be used for current work.

Along with this, the described method has serious disadvantages:

1) First of all, some animals cannot be caught with crushers, in particular, lemmings and steppe pieds, which are very important in their areas of distribution. The opinion that shrews do not easily fall into traps (Snigirevskaya, 1939; Popov, 1945) is refuted by a number of authors (Yurgenson, 1939; Formozov, 1945; Bashenina, 1947).
2) The results of catching and, therefore, accounting are influenced by the quality of the trap and the personal abilities of the person doing the accounting.
3) The same bait has different effectiveness due to weather conditions and the nature of the biotope (food supply, etc.).
4) Technical imperfection in the design of the crushers, sometimes slammed not only by animals, but even by insects and slugs.
5) With high population densities and a one-time inspection of traps, density indicators are underestimated, compared with those found in nature, since each trap can catch a maximum of one animal per day. Nevertheless, relative counting using crusher traps is currently the most accessible and effective, especially in the forest zone.

To quantitatively count the water rat, one has to resort to steel arc traps (No. 0-1), combining catches with direct counts of the animals, their nests and feeding tables. Based on the instructions for counting the number of rodents, published in 1945 by the State Institute of Microbiology and Epidemiology of the South-East of the USSR (Saratov) and the personal experience of A. N. Formozov (1947), we can recommend the following options for the method of quantitative counting of the water rat in various conditions:

1. “Trap-linear” technique. Arc traps without bait are placed at all water rat burrows along the coastline on several sections of the coast 50-100 m long, separated from one another by equal intervals (to eliminate arbitrary selection of areas). Traps are inspected daily, caught animals are removed, and slammed traps are alerted again. The traps remain for several days until the catch drops sharply. The results of catching are listed for 1 km of the same type of coastline. The population indicator is the number of rats caught in a kilometer area.

2. “Trap-platform” technique. It is used in “diffuse” settlements of water rats away from the coastline (on sedge hummocks, semi-flooded thickets of willows, cattails, reeds, wet meadows, etc.). Traps are placed on areas of 0.25-0.5 hectares near all burrows, on dining tables and at the crossings of feeding paths of water rats. If there are a lot of holes, their number is reduced by preliminary digging and traps are placed only near the opened passages. The trapping lasts two days, with traps being inspected twice (morning and evening). The accounting results are listed per 1 hectare.

3. In late autumn, and in the south, in areas with little snow, and in winter, during the transition of water rats to underground life, the trap-area technique is modified by installing traps in underground passages.

4. During high water, when water rats concentrate on narrow strips of manes, bushes, etc. along the banks of rivers, the animals are counted from a boat moving along the shore. Recalculation is done at 1 km of the route.

5. In conditions of extensive settlements in reed and sedge thickets in shallow waters, nests can be counted on sites or strips of 0.25-0.5 hectares, dividing nests into brood (large) and single. Knowing the average population of nests, the number of water rats per 1 hectare is calculated.

6. In places where nests are barely noticeable and there is nowhere to set traps (lots of water, no hummocks, etc.), you have to limit yourself to an eye assessment of the abundance of rats (in points from 0 to 5), counting the number of feeding tables in small areas, tapes or per unit length of the coast, and then converting the obtained indicators to 1 km or 1 hectare.

In contrast to the method of quantitative counting with crushers, another is being put forward - counting at trial sites using catch cylinders. Initially developed by Delivron, it was applied on a large scale in the Bashkir Nature Reserve by E. M. Snigirevskaya (1939). The essence of this technique comes down to the following. In the studied biotopes, three test plots measuring 50 X 50 m, i.e. 0.25 hectares, are established three times a summer. Each site is divided into a network of elongated rectangles with a side length of 5 and 10 l.

To do this, mutually perpendicular lines are marked with stakes, running in one direction at a distance of 10, and perpendicular to it - at a distance of 5 m from each other. Using specially made scrapers, paths 12-15 cm wide are dug along the lines marked inside the square and its delimiting lines; in this case, only the upper part of the turf is removed, and the exposed soil is trampled down. At each corner of the rectangles, i.e. at the intersection of paths, a trap jar is dug into the ground. It is more convenient to use Zimmer iron cylinders with a depth of 30 cm, a width of 10-12 cm, with a socket of 4-5 cm and a hole in the bottom to drain rainwater. The cylinders are made in such a way that three pieces fit into one another.

Snigirevskaya replaced the iron cylinders with ordinary clay jars (jugs), which, of course, are much more cumbersome. Krynki or cylinders are buried in the ground slightly below its surface. There are 66 traps installed at each site.

Rodents that prefer to run along paths rather than on grass, which impedes their movement, end up in jugs and most of them die of starvation. Snigirevskaya gives a very high assessment of this technique, especially emphasizing that it is possible to catch species in jugs that are not caught at all or are very difficult to catch in crushers (wood mouse, little mouse; shrews accounted for over 60% of all caught animals). Once installed, the trapping banks operate automatically, do not depend on the quality of the bait and produce large catches (over three summers, Snigirevskaya caught over 5,000 animals).

However, the method of accounting using trap jars suffers from such serious shortcomings that they exclude the possibility of its mass application, except for long-term stationary studies that do not require great efficiency. Detailed criticism is contained in the articles of Jurgenson (1939) and V. A. Popov (1945). The main disadvantages of the analyzed methodology are:

1) The traps used are very cumbersome, especially if you use clay jugs. To deliver them to the registration site, it is necessary to take a cart, and therefore test sites can only be set up near roads, which Snigirevskaya herself notes (1947) and which is in no way acceptable.
2) Setting up a trial plot is very labor-intensive, since you need to dig 66 holes and dig 850 m of paths. According to A. T. Lepin, this requires the labor of 2 workers for 1-2 days (depending on the hardness of the soil).
3) With high groundwater levels and rocky soil, burying jugs is almost impossible.
4) Large area sizes and a square shape, as shown above, are inconvenient.
5) Cleared paths, especially in dense bushes, greatly change the natural conditions.
6) Jugs are by no means universal traps and even some mouse-like rodents (for example, yellow-throated mice) jump out of them.
7) With large initial costs of labor and time for installation and extreme cumbersomeness, the method gives large catches solely due to the large number of trap days and therefore cannot be considered particularly intensive, as it seems. It can be recommended for obtaining bulk material for biological analysis rather than for quantitative purposes. Our attempt to use it in biocenotic studies in the Forest on Vorskla Nature Reserve convinced us of the impracticality of this technique. However, one cannot agree with the unconditional denial of this method by P. B. Jurgenson. V. A. Popov is right when he considers it necessary to simplify the technique of laying sites.

One of these attempts is the method of counting using trap trenches in combination with belt catching with crushers, proposed and tested over ten years by V. A. Popov (1945). “In the most typical place for the study area, earthen trenches were dug 15 m long and 40-55 cm deep (experience has shown that the depth of the ditch is not of great importance for the cunning of the animals), with a trench bottom width of 20-25 cm, and surface of 30-35 cm due to the slight inclination of one wall of the trench.

When digging a trench, the earth is thrown to one side, the one that is limited by the vertical wall of the trench. To construct a trench, depending on the nature and density of the tree stand and the density of the soil, it takes from 1.5 to 4 hours. At the ends of the trench, stepping back a meter from the edge, they dig in flush with the bottom of the trench along an iron cylinder 50 cm high and 20-25 cm wide (the width of the bottom of the trench). It is good to pour 5-8 cm of water into the cylinders, which is covered with leaves or grass. Otherwise, mice, voles and insects caught in the cylinders may be eaten by shrews, reducing the reliability of the count. The trenches are inspected every morning. All animals caught in the trapping cylinders are counted. This method can count not only voles and mice, but also shrews, frogs, lizards and insects.

We took the number of animals caught during 10 days of trench operation as an indicator of the abundance of micromammalia. At each station, we laid two trenches, placing them in the most typical places for the area under study, but no closer than 150 m from one another. We consider the period of time sufficient to obtain an idea of ​​the species composition and relative stocks of animals to be the work of two trenches for 10 days, i.e. 20 daily trenches. If it was necessary to obtain more detailed data on the fauna of the site, we increased the work of the trenches to 20-30 days, and for environmental studies we carried out trapping during the entire snow-free period.

“This method provides completely objective data, is simple and does not require a highly qualified worker (except for choosing a location for laying trenches).

“The negative side of the method is the difficulty in constructing trenches in places with high groundwater levels - along the banks of reservoirs, swampy lowlands, alder forests, etc. In addition, it must be taken into account that with the trench method a relatively small area of ​​the studied station is covered and, if desired, To further characterize the micromammalia fauna, it is necessary to increase the number of trenches or supplement this method with tape counting with Gero traps. The latter was widely used by us.”

Analyzing the results of accounting with trenches and traps given in Popov’s article, we ultimately come to the same conclusions as with regard to the methodology

Snigirevskaya - this technique cannot be considered as the main one, capable of replacing tape accounting with crushers. It is curious that Popov himself writes that “... both accounting methods give fairly close indicators,” but, we add, the Jurgenson-Formozov methodology is incomparably more flexible, operational and applicable in a wide variety of conditions, which cannot be said about the methods associated with excavation work.

The difficulties of direct observation of mouse-like rodents, the lack of objectivity of the results of catches with crushers involuntarily suggest the idea of ​​finding other methods of relative quantitative recording and, above all, establishing the possibility of using rodent burrows as a guiding feature. In steppe regions, counting burrows is widely used, but in a closed landscape it, of course, cannot play a big role.

Since the burrows of different species of mouse-like rodents are quite difficult to distinguish from each other and are very often used simultaneously by several species, counting burrows can only give summary indicators of the relative abundance of mouse-like rodents as a whole, without differentiation by species. At most, burrows can be divided into small ones (mouse-like rodents) and large ones (gophers, hamsters, jerboas, etc.). It is impossible to judge by the number of holes the number of animals inhabiting them, because one animal usually uses several holes.

Since the entrances to uninhabited burrows gradually, over the course of 2-3 months, become swollen, crumble and close, then by the presence of entrances one can judge the presence of animals here at least in the last 3 months before the survey, and by a number of other signs (see above) - to identify from among the still preserved entrances the truly inhabited ones. This makes it possible to use burrow counts for relative accounting purposes.

Holes are counted on routes or at sites. Formozov (1937) recommends conducting route censuses of the number of rodents in the spring, immediately after the snow melts, in the summer - during haymaking and harvesting of winter crops, in the autumn - after the harvest is completed and in the middle of winter - during thaws and fresh snowfall.

The routes, perhaps more straightforward, diverge along radii from the observation point. The length of each route is up to 10 km, and their total length for each recording period must be at least 50 km.

Distance is measured using maps, telephone poles or a pedometer.

The width of the count strip is taken from 2-3 m, depending on the density of burrows and the density of the grass stand. To simplify the counting technique, Rall (1947) recommends using limiters in the form of a rope or stick with hanging rods. This device is carried slowly by two workers in front of the counter. During long-term route calculations, the limiter can be the rear of the cart on which the counter rides.

The routes should evenly cover all the most important areas, as is always required in linear surveys. Route directions are marked on the ground and must remain unchanged from year to year in areas of perennial crops, pastures, pastures, virgin steppe, in ravines and on inconvenient lands. On arable land, you should try to lay routes as close as possible to the count lines in the previous season. “When taking a route survey of crop infestation, in order to avoid damage to the latter, it is advisable to move along roads, boundaries and outskirts facing virgin lands, fallow lands and other uncultivated lands. It should be borne in mind that rodents in fields are especially willing to stay in areas with an undisturbed turf layer (virgin soil, boundaries, roads) and from here they begin to move, populating the crops.

Therefore, the infestation of crops measured from a boundary or road will always be higher than the average infestation of the entire area of ​​a given crop. This must be specified in a note to the accounting data. Laying tapes along roads and boundaries makes it possible to detect the appearance of rodents on crops earlier than this can be done when studying the deep parts of the sown areas.” Not only burrows must be counted, but also cracks in the soil, which often form in the steppe during hot times and are readily inhabited by rodents (especially the steppe lemming, herd vole and others). The population of a crack is determined by the presence of ears of corn, fresh stems, etc., dragged there. Burrows are divided into inhabited, or residential, and uninhabited. In this case, the following categories and guiding features can be established:

"1. Inhabited burrow (fresh food remains, fresh droppings, freshly dug soil, traces of urine, paw prints in the dust, the rodent itself is noted looking out of the burrow, etc.).
2. Open hole (free passage into the hole).
3. A hole covered in cobwebs (often found in recently abandoned holes).
4. A hole, partly covered with earth or plant debris.
5. A hole, more than half or completely covered with rags and earth.”

We can propose an even more effective way of establishing the habitability of burrows, which is widely used when counting in areas - digging burrows.

During the count, all burrows are trampled or tightly filled with earth. According to Rall (1947), it is convenient to cover the entrance holes with lumps or plates of dry livestock droppings. The burrow should be closed tightly enough so that the shelter will not be disturbed by snakes, lizards or beetles.

During precise environmental work, the entrance openings are blocked by twigs of weeds, straw, etc. placed crosswise, which do not interfere with natural ventilation and the movement of insects and reptiles. The next day after digging, the number of opened holes is counted, which are taken to be residential, although it must be borne in mind that one animal can open several entrances. In general, it is very important to distinguish between residential and non-residential burrows when counting and processing data, since only by the number of the former can one judge the approximate abundance of rodents, but at the same time, the ratio between the number of residential and non-residential burrows and the change in this ratio indicates the direction of population dynamics - its growth or extinction.

Route accounting allows you to quickly survey large areas and does not require highly qualified workers, which is why it is accepted by land authorities.

The counting of burrows on the sites is carried out in the same way as on the routes.

The sites are 100-250 square meters in size. m, but in such a way that a total of 0.25-1 hectares were surveyed for every 200-500 hectares of the total area of ​​the registration area (Vinogradov and Obolensky, 1932). With uniform distribution of rodents, the sites can have the shape of squares, and with colonial (spotted) distribution, more objective indicators give elongated rectangles 2-3 m wide. When counting burrows in fields among forest belts, you should take just such sites, placing them in all main types of field crops in a straight line across the entire field, starting from the edge of the strip deep into the crop, since under these conditions rodents are distributed very unevenly and are usually concentrated near tree plantings. Therefore, the distance between the sites on the periphery of the field should be less than in the center.

The method of laying out sites developed by N.B. Birulya (1934) has proven itself to be excellent: “The trial area is set out in the shape of a circle, for which a wooden stake is taken, about 1-1.5 m high. It is hammered in the center of the area chosen for recording. A ring of thick wire is put on the stake so that it rotates freely around the stake, but does not slide to its base, but is always at a height of 70-130 cm from the surface of the ground. One end of a cord (fishing cord, antenna cord, etc.) is tied to this ring. The entire cord, 30-60 m long, is marked every 3 m with twine loops. Then two willow rods 1.5-2 m long are taken. At one end, each of the rods is attached to a loop. The opposite end remains free. The first rod is tied to the very end of the cord, the second - retreating 3 m inside the circle to the next loop.

“When counting, the worker, holding the free end of the cord and holding it at approximately chest height, moves in a circle. The observer walks next to the worker, stepping back a little and inside the circle, and counts all the holes that come across between the willow twigs dragging along the ground. Having made a full circle, the worker transfers the outermost rod to the next loop and winds the remaining 3 m of cord. So, sequentially, in concentric circles, all the burrows within the plots are counted.

“As can be seen from the description, the length of the cord is at the same time the length of the radius of the trial area. Therefore, the required size of the test area is selected by changing the length of the cord. With a cord length of 28.2 m, the area of ​​the circle is 0.25 hectares, with 40 m - 0.5 hectares, with 56.5 m - 1 hectare, etc. It is clear that the width of the counting strip can also be adjusted by increasing or decreasing the distance between the loops to which the rods are attached.

“It goes without saying that the device can only be used in open steppe conditions devoid of tall bushes.

“This method completely solves the problems. A certain radius of each of the concentric circles automatically eliminates the possibility of repeatedly walking in the same place, without leaving any missed space. The rods dragging along the ground always maintain the standard width of the registration strip. The observer just has to go and count the holes.

“The circle method, when compared with the rectangular area method, has the following advantages:

1) The circle method gives greater accuracy and is less tiring for the examiner.
2) With this method of counting, there is no need to have a measuring tape or tape measure.
3) If it is necessary to re-count in the same place, the circle requires the construction of one sign, which is easier to put up and then find. With the square method, you need to put four signs.
4) Very labor-intensive aspects of work, such as cutting out the sides and corners of a site, placing corner marks, necessary with the method of rectangular areas, are completely eliminated with our method.”

Finding and counting holes in the forest is fraught with such difficulties that it cannot be used for quantitative accounting purposes, with the exception of certain special cases. For example, D.N. Kashkarov (1945) describes a census of voles (Microtus carruthersi) carried out in the Zaaminsky Nature Reserve by N.V. Minin. These voles dig burrows exclusively under the crowns of juniper trees. On an area of ​​1 hectare, 83 trees were counted, of which 58 had burrows, and 25 did not.

The average percentage of infection ranged from 64.8 to 70%. Catching under the trees for several days made it possible to approximately determine the number of rodents living there and make calculations per 1 hectare.

We practiced counting burrows in small sample plots during biocenotic studies in the spruce forests of the Lapland Nature Reserve.

When working in an open landscape, the method of quantitative counting through continuous excavation of burrows and catching rodents on test sites is widely used, which brings us closer to an absolute count of rodents. At the same time, this work provides the researcher with abundant material for biological analysis.

Excavation of holes is carried out on test sites. Their number should be such that it covers at least 300-500 burrows for each biotope. “Before starting to excavate a large complex colony,” advises Formozov (1937), “it is necessary to thoroughly understand the location of individual groups of burrows and work according to a known system, pushing animals from less complex shelters to more complex ones. When the work is done in the reverse order, when a large group of holes is opened first, animals escaping from the spare holes are often hidden under layers of earth in a large dug up area, which necessitates repeated work in the same place. In the area allocated for work (recording) all groups of burrows are subject to excavation, regardless of whether there are traces of rodents near them or not... When excavating, one should gradually, meter by meter, open the passages, moving in each group of burrows from their periphery to center. It can be useful to make it difficult for animals to run across to neighboring colonies, when starting excavations, to open up all the available passages for some distance before going deeper to the nesting chamber. In place of the opened areas, it is advisable to leave trenches with steep walls, 10-12 cm high. This is quite enough to delay for some time the running of not only a vole or pied, but even a faster mouse, which makes it much easier to catch animals jumping out of deep parts of the burrow... For each opened group of burrows, the number of passages is counted, and a general count of burrows in a complex of groups is also given, uniting them into one colony, if its boundaries are clearly visible. At high population densities, when there are no boundaries between colonies, and all burrows connected by ground paths and underground passages merge into one huge town, a total count of the number of burrows (burrows) is given. Each site designated for recording and excavation must be located within the boundaries of one particular rodent station... The pits formed at the excavation site are filled up and leveled immediately upon completion of the work.”

When excavating burrows, simultaneity is of great importance. Depending on the hardness of the soil, excavation requires more or less physical labor, but under any conditions cannot be carried out by one observer, since it is impossible to simultaneously dig, catch quickly escaping animals and keep the necessary records. “The results of excavation accounting can vary significantly depending on the skill, conscientiousness of the workers and the qualifications of the specialist, the ability to look for holes where animals are hidden and understand the labyrinths. The breaking of each hole must take place under vigilant control, and this complicates the work of the observer in the presence of several workers” (Rall, 1936). According to Rall, due to this, accounting by excavating holes “...is available only in certain circumstances and, first of all, in the hands of an experienced field ecologist who has material resources.”

Counting by continuous digging of holes and catching animals is applicable, in addition to steppe species, to lemmings. The easiest way to dig up burrows is the Ob lemming, since its burrows in most cases are located in a peat layer that can be easily dug out with a knife (Sdobnikov, 1938).

When processing excavation data, the following points are noted:

1. The total area of ​​the excavation sites surveyed.
2. The total number of burrows dug and the number of burrows by rodent species.
3. Average number of burrows per 1 ha of the most important biotopes; the same for rodent species.
4. Average number of burrows in a colony or group.
5. The total number of inhabited and uninhabited colonies or groups of burrows. The same - as a percentage of the total amount of colonies studied. (All colonies and groups in which rodents or fresh food remains were found are considered inhabited.)
6. Total number of rodents caught by species.
7. Average number of burrows (movements) per rodent (including cubs).

If for some reason it is impossible to dig holes (for example, on arable land), pouring water on the animals is used. For this, it is best to use a large barrel on a cart and iron buckets, and on walking routes - canvas ones.

V.A. Popov (1944) used winter snow-covered surface nests for the relative accounting of the common vole - this most widespread inhabitant of meadows and fields. These almost spherical nests woven from grass, lying on the surface of the ground, are especially noticeable during the period of snow melting and before the development of a closed grass cover. Surface nests were counted along routes laid in characteristic vole habitats. “During the surveys, the length of the station crossed in steps and the number of nests found there were recorded. It is better to do the accounting together. One, having marked some landmark (a separate tree, bush, haystack, etc.), walks in a straight line, counting steps and marking the stations crossed with a counting tape. The second one counts the nests and inspects them, reporting the results for entry into a notebook. In order for the width of the counting strip to be constant at all times, the census takers are connected with a cord 20 m long. The length of the counting route should not be less than 3-5 km, i.e. 6-10 hectares.” As Popov's observations in Tatarstan showed, the data on counting vole nests are in good agreement with the calculation of them by catching them with crushers. At the same time, counting surface nests is very simple and can therefore be used as an auxiliary method for the relative counting of some species of small rodents.

Recently, successful attempts have been made to use it for the purpose of relative accounting of dogs. They have proven themselves especially well in the tundra when counting lemmings, which, as is known, are very difficult to catch with ordinary crushers. With some training, the dog not only learns not to eat animals, but even to catch them alive. It is better to keep the dog on a leash, which, although it affects its performance, allows you to maintain the known width of the recording tape. Not only caught rodents are taken into account, but also those that the dog hunted but was unable to catch. With some skill, you can see by the dog’s behavior what kind of animal it is hunting for - a lemming, a Middendorff’s vole, etc.

Route survey with a dog gives the best results in the open tundra, but in dense bushes it is almost impossible (Korzinkina, 1946). Of course, this method is very relative and comparable only when using the same dog or when assessed in points.

Lemmings can also be counted on routes on foot, on reindeer and from reindeer sleds. “Walking across the tundra on foot, the observer notes in a notebook all the lemmings that have run out in a strip 2 m wide. The counting strip will be the same width when riding a deer. When riding on a sled pulled by three reindeer, the width of the strip increases to 4 m.”

The best results are obtained when working “in clear, calm weather with slight frost, when lemmings are most active and, moreover, are easily driven out from under cover by both a walking person and especially trotting deer.” Along the way, a visual survey is carried out and the boundaries of the main habitats of lemmings are marked, or the distance is measured with a pedometer. The obtained data are corrected by continuous catches on sample sites and recalculated to the total area (Romanov and Dubrovsky, 1937).

As an auxiliary means of determining the relative intensity of migration of Norwegian lemmings in the Lapland Nature Reserve, the number of carcasses of animals that drowned in the lake while trying to swim across it and were thrown onto the sandy shore was used (Nasimovich, Novikov and Semenov-Tyan-Shansky, 1948).

The relative accounting of small rodents based on the pellets of birds of prey and owls, proposed by I. G. Pidoplichka (1930 and others), has proven itself to be excellent in the steppe regions and has become widespread there. S.I. Obolensky (1945) even considers it the main method for recording harmful rodents. The technique boils down to the massive collection of bird pellets, extracting animal bones from them, identifying them and statistically processing the resulting material. The collection can be entrusted to technical assistants. Collection proceeds quickly; according to Obolensky, comprehensive material for an area of ​​200-500 square meters. km can be collected in literally two or three days. At the same time, exceptionally abundant material falls into the hands of the collector, amounting to many hundreds and even thousands of rodent specimens. For example, based on bones from pellets collected during 12 excursions in the area of ​​the Karaganda Agricultural Experimental Station in 1942, the presence of at least 4519 animals was established (Obolensky, 1945). The number and species composition of exterminated rodents is determined by the number of upper and lower jaws. The remaining parts of the skeleton provide additional material. To facilitate and clarify the definition, it is useful to prepare in advance, by sewing onto pieces of cardboard, all the main parts of the skeleton of rodents of the local fauna, in order to have samples for comparison with bones from pellets.

If pellets are collected regularly in a known area and the places where they accumulate are completely cleared, then by the number of pellets themselves one can judge the relative abundance of small mammals at a given time. The relative abundance of different species of animals is determined from the bones of the pellets. Although small animals become prey for predators not strictly proportional to their numbers, but depending on the method of hunting of the predator, the behavior of the animals and the nature of the habitat, nevertheless, as the observations of both Pidoplichka and Obolensky showed, “... digital indicators of the number of different species of animals established by the number of their bones in pellets, they characterize the quantitative relationships of these animals in nature quite close to reality and are especially suitable for determining the composition of the population of mouse-like rodents” (Obolensky, 1945).

But observations of the birds of prey themselves, and their relative quantitative counts can be used as an indirect indicator of the abundance of rodents, since in general we can say that the numbers of both are in direct proportion. Particularly noteworthy are the field, meadow and steppe harrier, short-eared owl, steppe eagle, snowy owl, partly the rough-legged buzzard and the buzzard. “The abundance of predators in winter indicates the well-being of the ongoing wintering of rodents, which in the event of a favorable spring creates a threat of an increase in their numbers. The abundance of predators during the nesting period indicates that the rodent population has successfully survived the critical period of winter and spring; the threat of a sharp increase in the number of rodents is becoming real. Finally, in autumn, an increase in the number of predators due to the addition of those migrating from neighboring areas to the local nesting ones indicates a significant increase in the number of animals over the summer. In some cases, systematic monitoring of predators makes it possible not only to establish the presence of an existing outbreak of “mouse scourge,” but to a certain extent to predict it.

Observations of predators cannot replace direct observations of the life of a population of small rodents, but they serve as a very useful addition, since predators are clearly visible and easier to take into account. The latter is especially striking when there are few rodents, when their population turns out to be dispersed and difficult to count” (Formozov, 1934).

The original method of quantitative accounting using ringing was proposed by V.V. Raevsky (1934). “The method of quantitative accounting we propose,” writes the named author, “is similar to that used in physiology, when it is necessary to determine the total amount of blood in a living organism. So, after inhaling a certain amount of CO (carbon monoxide - carbon monoxide) or after introducing a colloidal dye into the blood, the content of foreign impurities in a small measured volume of blood is determined; the total amount of the latter is derived from the dilution thus obtained.

“In exactly the same way, those and we, wanting to determine the number of individuals of any species in an isolated observation area (an island, a colony, a sharply limited station), catch some of them, ring them and release them back, and in subsequent samples obtained by catching, shooting, collecting dead animals, etc., the percentage of occurrence of the specimens we have noted is determined.

“Blood circulation in the body guarantees physiologists the uniform distribution of all its elements, and therefore the likelihood that the percentage of impurities in the sample taken will be the same as in the entire volume of blood being tested. When determining the percentage of ringing by taking a sample from one point, we must also be sure that the ringed specimens are distributed fairly evenly throughout the total mass of the population under study... Such a uniform distribution of ringed individuals in the population that we need is not only possible, but, given certain conditions, obviously occurs in nature..."

Raevsky applied his technique when studying the ecology of house mice in the North Caucasus, where they accumulate in huge numbers in stacks of straw. The mice are caught by hand, ringed (see below for a description of the ringing technique) and released back. A few days later n3 is produced; catching, the number of ringed and unbanded animals among those caught is counted, and the percentage of ringed animals is calculated. Knowing the number of ringed animals released for the first time (n) and having now established the percentage of marked individuals in the population (a), we can calculate the total number of rodents in the study population (N) using the formula

N=n x 100/a

For example, 26 mice were ringed and released back into the stack. A few days later, 108 rodents were caught here, including 13 ringed rodents (12%). Using the formula, we find that the entire population consists of 216 animals:

N= 26 x 100 / 12 =216

If there were several repeated catches, then the population size is calculated using the arithmetic mean.

Tests carried out by Raevsky showed high accuracy (more than 96%) of his technique.

“For the practical application of the method of quantitative accounting by ringing, you need to have the following prerequisites:

"1. Banding of the species under study should not present too many technical difficulties, otherwise a sufficiently high percentage of banding will not be ensured.
"2. The researcher must be sure that during the time elapsed from the moment of banding to taking the sample, if it is taken from one point, there has been a uniform distribution of individuals within the population.
"3. The animal population being counted must live in a limited area.
"4. Knowledge of the biology and ecology of the species should provide the observer with the opportunity to make appropriate adjustments to the obtained figures (for example, reproduction in the period between banding and sampling, etc.).”

According to Raevsky, the method of counting by ringing is quite applicable not only to mouse-like rodents, but also to ground squirrels, gerbils, water rats, bats and other mass animals living in dense colonies.

When reconnaissance studies of mouse-like mammals, one should not miss any opportunities to characterize the state of their population and, in particular, use an eye-based assessment of their numbers. Numerous correspondents can be involved in this work, as the organizations of the crop protection service and the service for forecasting the number of game animals successfully do.

N.V. Bashenina and N.P. Lavrov (1941) propose the following scheme for determining the number of small rodents (see p. 299).

According to Bashenina (1947), the visual assessment given by the correspondents is in good agreement with the results of quantitative counts on tape samples with crushers and with the counting of residential burrows along the routes.

When counting by eye, the scale for estimating numbers in points, proposed by Yu. A. Isakov (1947), can be used:

0 - The species is completely absent from the area.
1 - The number of species is very small.
2 - The number is below average.
3 - The number is average.
4 - The number is high, noticeably higher than average.
5 - Mass reproduction of the species.

At the same time, they use all kinds of observations both on the animals themselves and on the traces of their activity - paw prints on the snow and dust, food, the number of winter nests melting from under the snow in the spring, etc., since together they can give there is a lot of interesting and important information and it is good to complement the quantitative data.

Thus, we have at our disposal a number of methods for estimating the number of small mammals that have both positive and negative properties, and it is up to the ecologist to choose the method that best suits the assigned tasks and working conditions.

However, none of the listed methods provides data on the absolute number of animals in the study area. Meanwhile, these data are very necessary for both theoretical and applied problems.

Some fairly successful approaches to this goal are the method of completely excavating holes and catching rodents.

But it is applicable only in open landscape conditions. In the forest, an absolute count of small mammals is theoretically conceivable through their continuous catching in pre-isolated areas.

A. A. Pershakov (1934) suggests laying test plots measuring 10 x 10 m or 10 x 20 m, which should be surrounded by two earthen ditches, about 70-100 cm deep and a bottom width of 25 cm. The internal slope of the internal ditch is gentle, at an angle 45 degrees, and the outer one is vertical. The outer protective groove has a square cross-section. In the corners of the ditches, flush with the bottom, trapping cans are dug in. The inner ditch serves to catch animals escaping from the test site, and the outer one protects against animals from entering from the outside. In addition to trapping cans, crushers are used and, finally, trees are cut down and even stumps are uprooted. This shows how labor-intensive it is to lay out each site. It is possible that while digging ditches, some of the animals will run away.

E.I. Orlov and his colleagues (1937, 1939) isolated the areas with a steel mesh, and then caught the animals with crushers. The site is shaped like a square or rectangle with an area of ​​400 square meters. m and is fenced with a steel mesh with 5 mm cells. The height of the mesh above the ground is 70 cm; in addition, to avoid undermining, it is buried 10 cm into the ground. A double-sided tin cornice, 25-30 cm wide, is installed along the upper edge of the mesh, preventing animals from climbing over the fence. The mesh is fixed on vertical iron posts that are stuck into the ground. The catch of animals living in an isolated sample area is carried out over 3-5 days using crushers and other traps so as not to miss a single animal. The number of traps should be sufficiently large (80; m), at least one for every 5 square meters. m. After the final isolation of the site and placement of traps, a schematic plan of the site is drawn up, on which burrows, bushes, trees, stumps, numbers of traps, and subsequently - places where animals are caught are marked (Fig. 73). Catching stops after nothing has been caught in any of the crushers for three days. You should take into account the possibility of some rodents leaving the fenced area along tree branches.

The construction of such an isolated site requires significant material costs (mesh, tin, etc.) and is, as the authors themselves admit, a cumbersome and labor-intensive task. It takes 30-40 man-hours to lay out the site.

Rice. 73. Schematic plan of an isolated area for counting mouse-like mammals (from Orlov et al.)

Therefore, accounting on isolated sites cannot yet find application on a wide scale, but only in special stationary studies, for example, in the study of forest biocenoses, where obtaining absolute indicators is absolutely necessary.

First of all, it is important to establish the number of species being studied, population density, since it is closely related to the entire ecology of animals and is of diverse theoretical and applied interest.

Without data on the number of species included in a biocenosis, it is impossible to judge their significance, it is impossible to imagine the structure of the biocenosis and its dynamics in space and time, and it is impossible to study the dynamics of populations of individual species.

Knowledge of the number of animals is necessary for the proper organization of pest control, in particular, for making forecasts for the mass appearance of rodents; population density has a direct impact on the spread of a number of epizootics; Quantitative recording of commercial and game animals is the basis for hunting management planning.

The main objective of quantitative censuses is to obtain data on the number of individuals in a known area, or at least on the relative abundance of species. In accordance with this, two types of quantitative accounting are usually distinguished - absolute and relative. However, it is impossible to draw a sharp line between them, since only in relatively rare cases is it possible to obtain a truly complete picture of the abundance of any species in a given area; usually, so-called absolute counts provide only more or less accurate results. This is not surprising, given the enormous difficulties associated with counting terrestrial vertebrates, which are characterized by great mobility, caution and secrecy. Even the relative quantitative accounting of mammals, birds and reptiles is incomparably more difficult than the accounting of invertebrates, and even more so of plant objects. This leads to the main requirement for any method of quantitative recording of vertebrates - it must be based primarily on the ecology of the animals being counted in a given specific environment.

Therefore, quantitative accounting should be preceded by preliminary familiarization with the main features of animal ecology and the biotopes of the study area. The following points are of greatest importance, as shown by I.V. Zharkov (1939):

1) The nature of distribution by habitat;

2) The tendency to form more or less permanent groups: herds, flocks, broods, etc.;

3) The presence of more or less clearly defined hunting areas, overlapping one another or isolated;

4) Tendency to form more or less regular seasonal accumulations;

5) Daily and seasonal changes in activity;

6) Daily and seasonal migrations and migrations.

Therefore, the methodology must be very flexible and different for different life forms of animals in different landscape and geographical conditions and in different seasons of the year. Attempts to excessively unify the methodology are doomed to failure. However, for any particular group of animals, one must strive to standardize accounting techniques in order to obtain completely comparable results. Along with the specified requirements, the quantitative accounting methodology must provide sufficiently accurate (in relation to the research objectives) results and, moreover, be downtime.

Thus, to summarize, we can say that the quantitative accounting methodology should be built on the basis of the ecology of the species being taken into account, landscape-geographical conditions, season, specific objectives of the study or economic activity and give, with minimal effort and expense, the most reliable results. Failure to comply with any of the above conditions will have a negative impact on performance.

Quantitative recording of terrestrial vertebrates is of two types: linear and areal. In the first case, individuals are counted along a more or less long line, on both sides of it, and the duration of the count is determined either by time (an hour, two, etc.) or by a known distance. As for the width of the registration strip, some authors do not precisely record it, but determine it solely by the distance at which reliable recognition of animals is possible by ear, with the naked eye and through binoculars, so that somewhere in the steppe this strip is for some species (for example, meadow whitings or pipits) will be equal to a few meters or tens of meters, and for others (large feathered predators) - hundreds of meters, which is acceptable only when studying and recording one species. But more often the count is made at a certain distance from the main line, sometimes greater or less depending on the nature of the terrain and species composition. In this last case, we essentially get the same area accounting with the only difference that the accounting area has the form of a highly elongated quadrangle. A linear survey, in which the terrain is intersected at a more or less significant distance, is often called an ecological section, or, in the terminology of American ecologists, a transect.

When counting on areas, an area of ​​square or other shape and size, determined by the species characteristics of the animals, is first allocated on the ground.

Both transects and sites should be laid out in a fairly typical and uniform area to facilitate the subsequent recalculation of the obtained data for the entire area of ​​the biotope under study. Generalizing the census results on heterogeneous areas (including several biotopes at the same time, which is quite possible in a mosaic landscape) will require some special techniques, which we will discuss below, in the section on rodents.

When setting up census plots, one must also take into account the fact that even in relatively uniform biotopes, animals are unevenly distributed. The more complex and heterogeneous the living conditions, the more complex the nature of dispersion is.

Depending on the ecology of the animals, the census can be carried out by direct observations (by ear, with the naked eye or with binoculars), by indirect signs (traces, burrows, excrement, pellets, etc.) or, finally, by capture.

The census can cover both permanent groups of animals and their seasonal concentrations, and can also be carried out during seasonal movements.

Data obtained from animal counts, for ease of comparison, are usually recalculated per kilometer of track (for linear counting), per hectare or square kilometer (for counting on trial plots). For hunting and commercial animals, it is advisable to take larger areas - 1000 hectares, i.e. 10 sq. km. The numbers related to this area are called indicators. If accounting data or figures characterizing the number of hunted animals and birds are related to the total area of ​​the entire study area or hunting area, then total area indicators are obtained (indicated for brevity by the corresponding letter symbol; see below). When determining the relative number of animals for individual biotopes or habitats (lands) characteristic of them, indicators are obtained by land (indicated by the same letters, but with an additional icon).

The indicator obtained by dividing the number of animals by a particular area is called the stock indicator (z and z1). When using data on the relative accounting of animals by tracks, they are recalculated either per 1000 hectares or per 10 km of path and obtain the accounting indicator (y and y1). Production indicators are designated d and d1; output indicators (i.e., workpieces) are v and v1.

When organizing quantitative accounting and processing the results obtained, you have to operate with quantitative indicators that need not only a biological, but also a mathematical explanation. In connection with the latter, the following considerations by Prof. P.V. Terentyeva (in litt.): “Unfortunately, the mathematical theory of quantitative accounting has not only not yet been developed, but most researchers do not even have a clear understanding of what exactly the numbers they receive represent. From a statistical point of view, any quantitative count (with the exception of rare cases of a complete, absolute count of all individuals throughout the entire territory) is a “sample study”: from the “general population” (the entire area, biotope or population), one or more “samples” of that or other size. The following propositions can be mathematically proven:

1. The more samples are taken from the general population, the more reliable the result.

2. The larger the area or size of each sample, the more revealing the data obtained.

3. The distribution of sample plots within a homogeneous biotope should not be biased, otherwise the data obtained will lose their indicativeness (“representativeness”). In many cases, a staggered order can be recommended.

4. The more variable the phenomenon and, accordingly, the obtained indicators, the greater the repetition of observations and the number of samples should be.

5. Mass phenomena and rough dependencies are captured even with a small number of samples and repetitions, and vice versa.

6. The final accuracy of the statistical result depends to a greater extent on the number of repetitions than on the scrupulousness of an individual observation. Of course, it is necessary, however, to strictly adhere to the standardization of the methodology.

7. The reliability of transferring the results of sample studies to the general population (“extrapolation”) is higher, the larger the area or part of the total population that was covered by samples and the greater the replication.

The exact expression of the listed dependencies can be derived from the formulas of any course in mathematical statistics.”

Accounting for game animals on the territory of the Russian Federation is carried out according to uniform methods approved by the Main Directorate of Hunting and Nature Reserves. Before the development and approval of a unified set of accounting methods for all types of hunting resources, and this is a serious long-term work, in the practice of hunting, accounting work for a number of species is carried out in accordance with the scientific and methodological recommendations of game management institutions, scientists and hunting specialists. There are already methodological guidelines in place for many areas of improving accounting work.

According to the Regulations on the State Service for Registration of Hunting Resources of the Russian Federation, records of game animals in designated hunting areas are carried out by hunting users and at the expense of these organizations.

The registration of game animals is carried out by district game managers, game wardens of the hunting supervision service, game wardens of commercial and sporting farms, and game wardens of hunting farms; Qualified professional hunters are involved in the census. In the districts, the organization of registration work and the collection of registration material is carried out by the district game manager. In hunting farms and hunting farms of hunter societies, the organization of accounting work is carried out by the game manager of the farm.

Ground work in the areas is carried out by census takers, including qualified professional hunters. The district game warden provides census workers with forms and brief instructions for conducting censuses, provides oral instructions on methods, sets deadlines for carrying out work and submitting completed registration forms in duplicate.

During census work directly on the hunting grounds of industrial farms of the Far North, the main attention is paid to fur-bearing game animals. Ungulates over large areas are counted, as a rule, with the help of aircraft.

Winter registration of game animals

The route card is filled out at the accommodation. The number of tracks of different species of animals is calculated according to the route diagram for different lands, data on bird sightings, the length of the route by land category are transferred, and all other columns are filled in. A separate card is filled out for each route.

Traces of daily animal remains are carried out throughout the entire recording period. This work is entrusted to the most knowledgeable and competent hunters. It is advisable for each accountant to collect the daily traces of various types of animals.

To determine the number of game animals based on winter route census materials, it is necessary to know the average travel length of each species. This value is calculated based on tracking a sufficiently large number of daily tracks of individual animals.

Many animals can lie down several times during the day, so determining how old a track is in some cases can be difficult. To avoid mistakes, tracking should be carried out one day after at least a small powder.

Some ungulates have a clear daily rhythm: the length of their tracks can be determined exactly within a daily interval as follows. On the first day, the census taker goes out into the area and follows a fresh trail to find the animal. When approaching an animal (which can be judged by the state of the trail), extreme caution is necessary so as not to disturb the pursued animal. The daily trail is followed on the second day “to catch up” from the place of the first meeting to the point of its re-discovery. In this case, you should calculate the speed of your movement in such a way as to catch up with the animal 24 hours after the first meeting. When tracking, it is not recommended to scare away the animal until it is registered visually, which requires the census taker to be extremely careful. If the animal is nevertheless startled, this is usually easily determined by the nature of the trail or the noise of the fleeing animal. The final point of tracking in this case should be considered the place where the animal was before flushing.

Sometimes it is possible to hunt down individual individuals in two, three or more days. The description of such a move is of great value, since it is equivalent to two, three, etc., tracking. If such a move is made, when recording at the top of the tracking card, you should indicate that this is a two-, three-, four-day move of the animal. Sometimes they trail a herd (roe deer, elk, deer), a brood (boar) or a couple of animals. In this case, the number of individuals in the observed group is indicated next to the name of the animal species, at the top of the card.

A commercial hunter, as he accumulates experience of a long stay in hunting grounds, learns very complex patterns of behavior of wild animals and birds, knows their way of life very well, which allows him to carry out professional censuses.

Weather. Days with moderate frost, without precipitation and wind carrying drifting snow are favorable for tracking. On days with snowfalls, blizzards or crust on which the animal leaves no traces or leaves only faintly visible prints, work cannot be carried out.

You need to have with you a large format notebook or tablet, a compass and a tape measure (instead of a tape measure, you can use a stick with divisions marked on it).

It is more convenient to work together. In this case, after finding the trail, the trackers disperse: one follows the trail to the resting place or place where the animal settles, and the second follows the trail “to the heel” to the place where the animal was after the powder. Thus, the entire daily movement of the animal is completely exhausted. If the accountant works alone, he, depending on local conditions, first follows the trail or “heel”, and then in the opposite direction.

Measuring the length of the diurnal cycle. The length of the animal's course is measured in steps. Depending on the depth and condition of the snow, as well as whether a person is walking or skiing, the length of the step varies greatly. Therefore, you should measure your step several times during each trail. To do this, measure 10 steps and the resulting result is divided by 10. The average step length (with an accuracy of 1 cm) is recorded in a book.

Record. The trail tracking plan is sketched out schematically in a book or on a tablet. The number of steps is recorded on the same diagram. It is advisable to take measurements over small segments (for example, from the bedding area to the feeding area; during feeding; from the feeding area to the area where the animal stood, etc.). On these segments they mark which lands the animal walked through. Upon returning home, they fill out a “tracking card” and redraw the tracking diagram on the back of it. The tracking card is handed over to the district game warden or another person responsible for registration work in the area.

Processing of accounting data. The data from several routes of one meter are summarized and entered into the table as a separate line. Add up the length of the route for each category of land and the number of animals encountered in each category of land.

Then the accounting indicator Pu is determined: the number of tracks is divided by the length of the route (km) and multiplied by 10, to obtain the average number of tracks encountered per 10 km of the route.

To determine population density, the counting indicator (the number of tracks per 10 km of route) is multiplied by the conversion factor K. It is equal to 1.57 divided by the average length (km) of the animal’s daily movement. The coefficient is determined by the State Hunting Accounting Center of the Russian Federation and reported to regional hunting organizations. It can also be calculated based on tracking data in the region, if quite a lot of separate tracking has been carried out for each type of animal. The coefficient can also be determined by comparing animal counts at trial sites and routes, if the combined count was carried out in the same places and at the same time.

example. On an area of ​​300 hectares, 8 white hares were counted. In these places, an average of 24.3 hare tracks are found per 10 km of route. The population density P of hares at the site is equal to P - (8:300) x 1000 = 26.7 individuals per 1000 hectares. The conversion factor will be K= R/P = 26.7/24.3= 1.1.

If all the names of quantities are met, the population density is obtained in individuals per 1000 hectares.

Accounting of the main species of wild ungulates

The most common method is aerial census of ungulates, which is determined by the ease of surveying large areas and the possibility of obtaining a significant volume of primary material. Aerial surveys using photographic equipment to determine the number of ungulate populations (wild reindeer) in open spaces of the tundra and visual surveys of elk in the forest zone have become widespread.

For commercial hunters, accounting based on encounters and discovered traces of life activity is most acceptable. Being on his property for a long time, the fisherman usually knows quite accurately how many moose are kept and where; he is able to mark this on the site map in relation to the area

habitat. So, if animals are kept in a floodplain complex, then the number of moose is determined per 1 thousand hectares of these particular lands, etc. The exception is the so-called “camps”, when animals in winter gather from surrounding lands for relatively small food and areas with little snow. The population density, that is, the number of animals per 1 thousand hectares of such land, will not be characteristic of all other types of land, even those similar to the places of “stalls”, but where elk, for some reason, are not found in such numbers. In this case, visual accounting must be carried out precisely according to the “posts”.

In winter, excrement surveys can be carried out for elk, deer, and roe deer. During the period of feeding on woody food, that is, in winter, the excrement of ungulates differs in appearance from those excreted at other times of the year. The number of bowel movements in moose is relatively stable. Knowing the number of excrements left by elk over a certain period of time, it is possible to determine their number per animal for the entire winter season. The number of excrements varies depending on the habitat and age-sex structure of the animal population.

The census is carried out in early spring. To do this, you need to know the duration of the period of use of tree feed and the average number of excrements per day. The beginning of the period of feeding on winter food coincides with the appearance of the autumn color of the vegetation, and the end coincides with the appearance of the first leaves of the tree species eaten by elk: willow, aspen, birch and rowan. The average period of feeding on winter food for moose is 200 days.

The average number of defecations per “average” moose is determined by tracking the daily movement of the animal in the area where census work is carried out. Thus, in the northern regions, one adult moose produces 12-17 piles of excrement per day.

Determining the winter population of animals is possible only in places with a relatively constant number of animals. The census is carried out immediately after the snow melts, before the grass cover appears. Counting routes 4 m wide (the distance at which excrement is clearly visible) are laid in all types of land, in proportion to their area, that is, in large areas, more routes are laid and, conversely, in smaller ones, fewer routes are laid. Discovered old piles of excrement, which are usually covered with last year's grass and have a more intense black color, and fade in the sun, are not counted. To summarize, by means of simple arithmetic calculations it is possible to determine the density of the elk population in certain areas in the past winter, and therefore have a definite forecast for the next hunting season.

The moose habitat area is 100 thousand hectares; the duration of elk excrement in winter is 200 days; daily number of bowel movements (number of piles on average per animal) 15; total route length 120 km; registration area (registration tape area) 0.4x120=48 hectares; the number of recorded excrements is 240. The number of piles per 1 thousand hectares = 1000x240/48 = 5000. The density of moose (individuals per thousand hectares) = 5000/200x15 = 1.6. Total number of moose (individuals) = 1.6x100=160.

Registration of fur animals

Sable population count. According to the current methodological recommendations for counting the number of sable, this work is recommended to be carried out at the end or after the end of fishing, in February - March, before the appearance of crust. The technique of counting sable varies depending on the methods of counting.

Route relative accounting based on tracks. In contrast to absolute counts (also called quantitative), with relative counts it is not individual animals that are recorded, but their fresh, no more than a day old, tracks crossing the route. The accountant does not take on the task of determining the number of individuals (sables) and thereby avoids mistakes. The counting indicator is the number of tracks per 10 km of route (by type of land). Relative accounting is carried out on all routes through hunting grounds, i.e. at registration sites and during transitions from one site to another. Clerks continuously monitor the length of the route on the map, the duration of the move (by the clock) and by eye (with subsequent reconciliation on the map).

The routes cross lands and forests without choice, adhering to approximately the same direction. In mountain forest valleys they go “half a mountain”, without repeating the small bends of the river. In the sub-alpine belt there are edges of forest stands and elfin pine.

The route is marked by outlines M 1:10,000 and 1:25,000.

All traces no more than a day old are recorded, including all traces of animals that cross the route several times. A single daily wake is taken as one wake, a double and a reverse one - as two. A fattening is counted as one track (if the animal left the fattening in the direction from which it came); the path is taken to be four tracks. If the records are kept based on traces that are two days old, then their number is divided by two. For three- or more-day-old powder, in order to avoid confusion, only fresh—one-day-old traces—are taken into account. The outline of the route, drawn on the same day in the evening on a scale diagram, is the main primary accounting document.

Counting sable on trial sites (mapping the distribution of sables) is the main method of absolute (quantitative) counting. Sables are counted by their tracks in relatively small areas that differ in composition, food supply or degree of industrialization of the land.

Animals are mobile, their number on the counting site changes over time. Therefore, to obtain estimated population density indicators, several (at least three) test sites are laid out in each type or complex of land. A site located in the same type of land is preferable, but it is rarely possible to choose one. More often, sites are laid out in land complexes characteristic of the region, guided when choosing by knowledge of the area and data from exploration routes. It is desirable that the registration area be limited to lands that are unproductive or unusual for sable - chars, open fields, open valleys. Typically, the site includes a forested valley of a small river with streams and valleys flowing into it, or 2-3 adjacent valleys. The shape of the site is preferably round or square, but it can also be elongated depending on the configuration of forests, topography and other terrain features.

A site where there are no tracks or only one sable is counted does not give the right to calculate the population density of the animal. The boundaries of the site must be expanded until traces of at least two sables are discovered. With an expected density of less than one sable per 1000 hectares, the minimum area will be about 2.0 thousand hectares (20 km2), preferably somewhat larger. Smaller sites can only be established at a density of 3 or more sables per 1000 hectares.

The test site is passed through a network of routes, with the same outlines being maintained as in the case of relative accounting. The difference is that the recorder undertakes to determine the number of sables that left tracks (crossed the route). The tracks of individual animals are distinguished by size, sex of the animal, individual characteristics, and always by the direction of travel. The tracks belonging to the same sable are “grouped” on the outline (connected by a dotted line that follows the animal’s path). Errors in determining the number of individuals will be approximately the same in the direction of exaggeration or understatement and will overlap to a large extent. The “counted” sables from the outlines of the routes are transferred to the diagram of the trial site: in this way their distribution is mapped and the number is counted.

The routes pass the boundaries of the registration area, cross large homogeneous forests and low-value lands in order to more fully characterize them. Along 50 km2 of sable lands, it is necessary to pass at least 70-100 km of survey routes: this means that when laying parallel routes, they should pass 1-1.5 km from each other.

Multiple tracks make it difficult to keep track, so it is advisable to cross out the “recorded” tracks of animals – “overwrite them” so that on the way back, or repeating the route, it is easy to notice fresh tracks.

When carrying out exploration work in areas uninhabited and sparsely populated by sable, it is recommended to count on a route tape using additional indicators and coefficients for calculating the stock.

Recording on a route tape, the width of which is taken to be the average length of a sable's daily course, is widely used in winter route recording.

To calculate density, it is necessary to obtain, by tracking “model” sables, the average length of a sable’s daily walk that is reliable for a given area and time.

Having ready-made indicators of relative accounting, density is calculated in a simplified way: the conversion factor (K = 1.57), taken from formula (1), is multiplied by the number of tracks per 10 km of route.

Counting sable on a route tape, the width of which is taken to be the average diameter of the daily habitat of one animal, requires the census taker to have special skills in “reading” tracks, just as when counting animals on a test site.

In terms of the technique of execution, the outlines of this survey do not differ from the routes on the test site: all traces of one day ago are marked on them, based on the direction, size and other features of which the number of individuals crossing the route per day is determined. Traces belonging to one animal are “grouped”. The width of the counting tape is determined by tracking “model” sables.

The population count of squirrels is carried out in the autumn, during the pre-harvest period. For the European part of the Russian Federation, the best time is October, for the regions of the North and Siberia - the second half of September, since at this time it is possible to count the cubs of the second brood who left the nests, while the total mass of animals has basically already completed their migrations. To count with a husky, 3-5 routes are selected in the most typical natural conditions for a given area. The length of each route is 10-15 km.

The results of the count depend on weather conditions, which determine the activity of the squirrel and the performance of the dog. The greatest influence is exerted by wind, air temperature and precipitation. The census is carried out at a wind speed of no more than 11-13 m/s, at which large branches on the trees sway. When the wind is stronger, the dog not only hears the animal poorly, but may not even notice its movement. As a rule, when there is a strong wind in dense dark coniferous stands, the squirrel walks low, and in light coniferous or sparse dark coniferous forests it is less active. It is also necessary to take into account that the forest weakens the force of the wind.

For accounting, the most favorable air temperature is from 2 to 5 °C, but they can also be carried out at temperatures from -15 to 15 °C. A decrease in temperature below -15 °C reduces the activity of the animal, and an increase above 15 °C impairs the dog’s work, which negatively affects the reliability of records due to an increase in the number of omissions. An increase in temperature after frosty weather, when the squirrel is active and feeds for a long time, is favorable for surveys.

The routes are laid in typical squirrel lands, mainly in coniferous forest plantations, in such a way as to cover all the features of the relief and vegetation: stream forests, watersheds, edges, gorges. It is impossible to carry out censuses mainly in squirrel areas, otherwise the data on the number of animals will be overestimated.

To lay out routes, you can use the neighborhood network, but not roads and dirt paths, since the dog passes part of the route along them and, therefore, does not search for the animal.

Before conducting surveys, prepare a simple diagram of the area for future work and mark routes on it. In addition, the accountant must have a compass and watch, a notebook, pencils, route forms and preferably a pedometer.

Accounting for game animals with a dog

The dog must work well on squirrels, have a smooth and fast “shuttle” or “circular” search, not moving further than 100-300 m from the counter. A dog with a very broad or straightforward search is unsuitable for accounting work.

The width of the counting tape is determined by the width of the dog's search and is calculated by doubling the distance from the route line to the place where the squirrel was found by the dog, being equal to 50-100 m in dark coniferous stands, 200-220 m in light coniferous stands. The distance is determined by counting steps. If you have a pedometer, record its indicators at the beginning of the passage of each new type of habitat of the animal, indicating the age of the forest stand: spruce forest (ripe, ripening, middle-aged, young), etc. If there is no pedometer, at the beginning of the passage of each new habitat of the animal, record the time in hours and minutes , which makes it possible to calculate the length of the entire route and each habitat of the animal based on the sum of time. Typically, in forest areas, the walking speed of the census taker is 2 km/h, increasing to 3 km/h in the forests, not counting the time it takes to approach and look out for the animal.

The best way is to measure the route and its segments with a curvimeter or ruler on a large-scale map, for which you need to copy the diagrams in advance. In this case, the protein meeting places are plotted directly on the diagram, which facilitates record keeping and subsequent processing. It is advisable to carry out accounting together.

At the beginning of the route, the recorder writes down in the field diary: a) the name of the farm, forestry or the nearest settlement and the location, in relation to it, of the route (distance in kilometers from the beginning of the route from the settlement); b) accounting date (day, month, year); c) state of weather conditions - cloudiness, air temperature, wind strength, precipitation, depth of snow cover and its condition; d) a brief description of the habitat - its type, age of the forest stand, crown density, presence of undergrowth and regrowth of the main tree species (its density), composition of the forest stand. For mixed forest stands, all tree species are noted in descending order (for example, a spruce forest with an admixture of pine and birch). They assess the yield of the squirrel's main food: pine cones, seeds and fruits; e) start time of recording in hours and minutes.

The dog is allowed to search and begin to move along the route. Throughout the entire route, the nature of the dog’s search is noted: its width and coverage of the territory. In the presence of difficult-to-pass habitats, the time of narrowing the search and the width of the counting tape are noted. The time of search expansion is also noted.

The beginning of the squirrel's barking is also recorded in a diary (hours and minutes). After this, the recorder, counting the steps, approaches the skating area in a straight line. The size of a step or pair of steps is determined in advance by the accountant. Having found out the reason for the barking, when he finds a squirrel, he makes a note in his diary and writes down the type of tree. Notes the presence of an animal gnawing near the tree. If it is not possible to spot the squirrel, then, if you are sure that the animal is still in the tree, the recorder makes a note: the squirrel was found, but not detected. He marks the location of the squirrel on the route map. Next, the dog is put on a leash, taken away from the lapping area and again allowed to search. A note is made in the diary about the time the search began (hours and minutes).

At the end of the route survey, the time directly spent passing through each type of habitat is determined and the length of the route segments is calculated. In the future, encounters are summarized by habitat type and overall along the route. Depending on the type of habitat, the height of the trees, the density and development of the crowns, the dog detects one or another part of the squirrels present on the route tape. It has been experimentally established that, on average, in dark coniferous areas it detects 53%, and in light coniferous areas - 89% of the animals living there. When passing the route three times (with shooting animals), the dog, under favorable conditions, detects all the squirrels.

Counting small mustelids

The count of the number of small mustelids - ermine, weasel, polecat - is carried out using the ZMU method, but there are also certain modifications.

Ermine can be counted by tracks in the snow, laying out test areas of 5-10 km2. The routes are laid at approximately the same distance from one another. Having encountered traces of an animal, they are tracked or walked around, finding out the area of ​​​​its habitat, mapping it on a diagram: in this way the number of animals living here is determined. Counting ermine on a route tape is less labor-intensive. To do this, they walk along the banks of streams and rivers, noting all the traces of animals they encounter, indicating their size (large - K, medium - C, small - M). When processing counting data, it is believed that each track, different in size from the neighboring one, belongs to a different animal. In this way, the number of animals on the route traveled is taken into account.

When conducting route surveys, on the same days the average width of the ermine’s daily burrow is determined by tracking the burrows. The average width of the animal's daily movement is taken as the width of the counting tape. In areas rich in mouse-like rodents, the approximate standard for the average length of an ermine's daily walk is 230-270 m for a male and 115-135 m for a female. In areas with less food availability, the animal moves more widely and has a larger individual area. If there are sufficiently wide river basins, the routes are laid in parallel at a distance of 500 m from one another (route width).

Mink and otter census

Mink population counts can also be carried out in the summer, best with a husky dog ​​in the animal’s residential burrows along the coastline. However, more reliable data are obtained during winter tracking of mink. The mink's track is paired, round in shape, similar to the track of other mustelids. When jumping, the mink makes triple and quadruple tracks, in which the prints of the hind paws are located slightly behind the front ones. The tracks of females are smaller than those of males.

At the beginning of winter, before snow falls, the census taker walks around the banks of reservoirs and rivers, inspects the coastal strip, and notes traces of minks. The animal’s shelters are located up to 50 m from the shore; in winter, burrows are often located near the water itself. The count is carried out at the beginning of winter due to the fact that with the formation of voids under the ice, with the onset of severe frosts and the fall of deep snow, the animal rarely comes to the surface. Therefore, large errors are possible in the direction of underestimating its numbers when counting.

Mink tracks encountered at a distance of more than 250 m from one another are mistaken for the tracks of another animal. The census is carried out by continuously walking around the banks along the survey route. The mink population density indicator is calculated in relation to the length of the coastline, expressed in kilometers. It is impossible to extrapolate the obtained indicators to the entire length of the coastline if it has not been surveyed. It must be borne in mind that the mink does not stay in otter habitats.

The otter census is carried out in the same way, but due to its greater movement in the areas, the length of the survey routes should be much greater. The census is carried out before deep snow falls, and the weak development of subglacial voids during this period makes it possible to better record traces of the animal’s vital activity.

Because otters live in families, tracks of an adult female with several cubs are often found on the shoreline, the tracks of which are noticeably smaller. The concentration of otters in winter near ice-free areas makes it easier to count. A distinctive feature is the presence of often round holes that the animal uses. When the snow is deep enough, a furrow from the otter's belly and tail remains on it. The population density indicator is calculated in relation to the length of the coastline.

Arctic fox accounting

In the autonomous districts of the Far North there is a “harvest service” for the Arctic fox, presenting an annual forecast of the animal’s population. The population census required for forecasting is carried out in arctic fox dens, which, as a rule, are quite localized in the tundra zone. The burrows are located at high elevations in the relief, in well-drained places, and in a relatively compact manner. In the presence of extensive swampy lowlands, Arctic foxes settle on hills in a complex system of burrows. On the contrary, in hilly tundras, dens are characterized by group or single locations.

The accounting and methodological group of the district headquarters of the “harvest service” determines test sites for counting the number of arctic foxes, depending on the qualifications of the census takers and counting locations up to 50 km2 or more. In some areas or throughout the entire area, inhabited burrows are identified, the number of young animals on average per family is determined by observation, and the average family composition for inhabited burrows is calculated. At the beginning of summer (June), the young do not move far from the burrow, so such calculations can be quite accurate. Based on the average family composition and the number of occupied burrows, the approximate number of arctic foxes can be determined.

Since census work is often carried out in the same places where arctic foxes are concentrated during the breeding season, long-term accumulation of data and the experience of surveyors make it possible to reduce the duration of work. In order to predict the number, the state of the food supply of the Arctic fox, primarily mouse-like animals, and other natural factors are studied.

The census of the number of foxes, as well as the arctic fox, is carried out in burrows during the breeding season, in the forest zone - with a salary (extremely rare). However, the most acceptable method is the relative counting of foxes based on tracks on linear routes using the ZMU method.

Muskrat census

Current guidelines for counting muskrat numbers provide for several counting methods. Depending on natural conditions and resources, muskrat surveys can be continuous or selective. Selective surveys are carried out by laying out trial plots of 100 - 200 hectares in size so that they cover at least 10% of muskrat lands. Several typical lakes can be identified as test sites; The registration area can also be a hunter’s fishing area. In extensive fishing areas on large bodies of water, a relative count of muskrat numbers is practiced along the same permanent routes in spring and autumn.

Features of accounting work in field conditions. The experience of practical on-farm game management allows us to use certain features during registration work of certain species of game animals.

Sable. All other things being equal, the population density indicators of the species change in different types of forest from maximum to minimum in the following sequence: in dark coniferous taiga with an admixture of cedar; in the spruce-fir taiga (grass-shrub, cluttered, over-mature); in herbaceous-shrub larch forests or young forests in old burnt areas and clearings (with small-leaved renewal); in other types of forest; in areas unusual for the species (mountain tundras and meadows, wide pigweeds, swamps, etc.).

In a number of areas, sable is characterized by movements (2-3 year cycle) to the lower reaches of rivers, or, conversely, the animals visit the floodplain only periodically, preferentially staying on the slopes of ridges. Such a situation can significantly distort accounting data; this should be kept in mind. When taking surveys, one cannot limit oneself to examining only floodplain areas.

Squirrel. In fishing conditions, when a hunter travels the same route for 2 days in a row, the data can be processed using the following simplified calculation method (Smirnov, 1961): N = A/A - B (where N is the number of squirrels, A is the hunter’s catch on the first day, B - production on the second day).

Counting squirrels is often complicated due to its high mobility. In the conditions of observed migration, the average daily catch of a hunter becomes an important guideline for determining the number, i.e., the tendency to increase or decrease the number under various conditions, based on the average long-term level.

Column accounting

Preferred surveys are in the floodplain, cedar-broad-leaved forests (Far East), in shrubby swamps and marigolds with lakes. Higher numbers are in the foothills. According to a very rough scheme, the floodplain in the lower reaches of large tributaries belongs to the first zone of population density of the species; tributaries of the second and third orders belong to the second density zone. In the middle reaches, first-order tributaries flow to the second density zone, and second- and third-order tributaries flow to the third population density zone. The upper reaches of the rivers with all their tributaries belong to the third zone of population density.

In snowy winters, when there are few mouse-like species, Siberians can concentrate in empty or non-freezing springs. Without preliminary capture, counting is difficult. With the onset of severe frosts (December - January), the census gives large gaps, since the Siberian weasel may not leave the shelter for a long time. Its activity increases sharply at the end of February - March.

Ermine census

It is preferable to count with the first snowfall, and only in the floodplains of rivers and streams. In a significant part of its range, the stoat leads a rather secretive lifestyle, rarely appearing on the surface in deep snow.

Mink counting

It is better to carry out accounting in field conditions before freeze-up, since the resulting empty ice increases many times the accounting errors. It is necessary to carefully inspect (until mid-November, until the broods have settled) creases, bank slopes, and the sources of bays. In the habitats of the brood, trails, holes, etc. are visible. Outside the individual habitat of the brood, only traces of adult single individuals are found (traces of puppies are less common).

In March, the mink's activity increases, and the animal emerges more often from the empty ice. The mink is mobile, the length of its daily movement reaches 10-15 km.

Otter census

The daily cycle and individual habitat vary greatly and depend not only on food resources and the protective properties of the land. In places where there are almost no traces of an otter, since it appears in a given place periodically, the animal’s habitat can exceed a water area of ​​50-60 km (long).

Ground squirrels and marmots are counted in their residential burrows at sample sites in May - early June. The size of the site for counting gophers is no more than 20 hectares. Inhabited burrows are counted and the number of animals living within the site is determined visually or by trapping.

Chipmunks are counted on routes in early May (sometimes with a decoy). The minimum number of counted animals per day from which you can plan to harvest is 40-50 individuals.

Muskrat census

A qualitative assessment of the population is possible only taking into account the type of reservoir, its hydrological regime, and food supply. In floodplain reservoirs, the muskrat rarely makes huts, however, each family has 4-5 feeding burrows with a habitat area (in similar conditions) from 30-40 to 200 m. Spring-summer census (late May - early June) in brood burrows is carried out during the period when all movements of the muskrat end, the first litter appears, the number of occupied burrows approximately corresponds to the number of married couples. The spring number plus the average annual increase (the natural loss of young animals is excluded) allows us to speak, as a first approximation, about the procurement plan.

Beaver census

The beaver moves quite widely in the summer; traces of its activity can be found far from its main habitat, which makes it difficult to count. The sizes of a weak, medium and strong family can differ significantly. Coastal surveys during censuses (late autumn, before freeze-up, when beavers are already concentrated near settlements) increases the efficiency of this work.

Fox counting

In the practice of counting work during on-farm hunting management, the size of counting areas for foxes is at least 1.5 thousand hectares. Sites are established in connection with river floodplains, agricultural lands, etc., with differentiation into zones of different species densities (a known maximum of 10-12 individuals per 1000 hectares).

Badger count

Surveys on sites are possible if the abundance of the species is relatively significant. Mapping of colonies and relative recording of residential burrows along the routes are carried out. A fairly long-term recording (up to 10 days) on an area of ​​up to 1000 hectares is advisable. Good results are obtained by using badger-baited dogs. In rocky dens, the density of the species can reach 40 or more animals per 1000 hectares. It must be taken into account that in the summer the animals disperse over a fairly large distance (for a badger) (2-5 km) from the permanent settlement. Each adult animal can have 2-3 temporary burrows.

Registration of the raccoon dog

A general idea of ​​the species’ abundance can be obtained by examining typical habitats: the shores of lakes, swamps, bays, channels with muddy and sandy shores. Accounting is effective when early snow falls on sites (with comprehensive accounting).

Registration of red deer

Take into account during the period (September - October); the route should cover different types of land, from the lower reaches of the river to the upper reaches. Listening points are placed at least 3 listening radii from each other; with an average population density of the species, one point per 8-12 thousand hectares is sufficient. When listening, the approximate distance at which the animal can be heard is determined, the location is marked on a schematic map, then delineated. The number of bulls based on the population structure allows us to determine the total number of the species.

Roe deer count

In the summer, it is possible to examine salt licks, edges of mires, and springs, where traces are clearly visible on spits and muddy banks, and the individual area of ​​a roe deer is limited to several tens of hectares. In a number of places in the taiga zone, visual observation is possible (June - July) before sunset (males) from 18-19 hours and with the first onset of twilight (females), when roe deer go out into wind-blown open spaces to escape midges. A frightened male almost always gives a voice.

In winter, with snowfall of 25-35 cm, a significant part of the population wanders. The count of migrating roe deer is carried out across the identified paths (usually the floodplain of the river, pigweed, etc.) along clearings, old roads, winter roads, with registration of the traces encountered on the diagram. When crossing, roe deer walk in a chain. Their beds are distinguished by the ejection of snow almost to the ground.

Musk deer. Accounting at complex sites. Low population density - 2-4 individuals per 1000 hectares, average - 10-12, high - up to 40 individuals per 1000 hectares. The individual habitat of a musk deer ranges from 0.4 to 50 hectares, the daily footprint may not exceed 0.5 km; On the route, special attention should be paid to rocky outcrops and steep slopes with rocks.

In the summer-autumn period, an approximate estimate of the number is possible by examining the trails and “latrines”: 15-20 “latrines” per 1 km of route can approximately correspond to a population density of up to 35-40 musk deer per 1000 hectares. Experienced hunters believe that males “scratch” their hooves in the snow, leaving very characteristic thin stripes. On fresh roosts of males, the smell of musk is sometimes felt.

Registration of wild reindeer

In the forest zone, ground-based area and route surveys are carried out extremely rarely. The area of ​​suitable land for habitation within the range is many times larger than the area occupied by deer during the period of registration in the snow, therefore the registration area must be at least 15-20 thousand hectares. When crossing, the herd walks in a chain; The number can be determined by the places where the animals go to feed.

Boar accounting

In fishing areas, accounting is difficult, since the herds constantly move depending on the feeding situation, often over long distances. The counting area must be large enough (more than 15 thousand hectares); observations of the location and number of wild boars are mapped on a schematic map, followed by a digital count.

In deep snow, wild boar concentrate in horsetail thickets; in the spruce-fir taiga it lives on sedge, in the floodplain of small springs. The seasonal movements of the animal should be well known to the hunter: they are used during census work.

Waterfowl census

Waterfowl is not important in harvesting, but the hunter must give a general assessment of the number. The places and timing of mass migration of waterfowl are determined by observation. A visual assessment of abundance is carried out during daylight hours with a visual coverage width of up to 1 km. Species are identified according to the following scheme: geese, pintail, mallard, pochard, teal, merganser. The average number of birds in flocks is determined along the way, if possible - daily.

Census of nests in reservoirs is carried out from July 1 to August. The best sites are reservoirs heavily overgrown with a variety of aquatic and semi-aquatic vegetation. Land of average quality is water bodies that are lightly overgrown or overgrown mainly with sedges, reed grass, and reeds. The worst areas - there is no aquatic vegetation; along the banks the plants are represented mainly by sedges.

Sites are laid out (up to 10% of the reservoir site), the average number of broods per 100 hectares and the average number of ducklings in broods are determined. At the same time, males and single females are visually counted from the boat. When processing the received data, an adjustment is made for poor accounting accuracy. On average, 80-85% of broods are taken into account in low water, and 40-45% in high water.

When studying animals in nature, they use the method of direct observations of them and the method of studying animals based on traces of their life activity.

Direct observations carried out on an excursion or while lying in wait, from a secluded place. The excursion route is planned and thought out in advance. Features of the lifestyle and behavior of animals depending on the season, time of day, and weather must be taken into account. The tourist must walk slowly and silently, looking around and listening all the time, and if necessary, stop immediately and freeze in place. It is important to spot the bird before it becomes alert. When approaching an animal, you need to take into account the direction of the wind, keeping in mind that animals have a heightened sense of smell and hearing.

When lying in wait, they set up ambushes near nests and burrows, at feeding sites, etc. When lying in wait, you must carefully camouflage yourself - hide in dense bushes, tall grass, etc. Watching is best done in the morning or evening hours, when animals are most active.

Voice is of great importance in the study of birds. You can determine the type of bird by its calls and song. Screams and songs are a signal by which an observer can easily sneak up to the bird and make direct observations. The study of bird voices should begin with simple, frequently heard birds (finches, tits, and other birds). This will allow you to get acquainted with the calls made in various cases: alarm cries, quarrels, calls for chicks, etc.

A method for studying animals based on traces of their life activity. Direct observations are not always possible and not on all animals (for example, mammals). By paw prints, food remains, scraps of fur, droppings, and burrow constructions, you can determine the type of animal. In the field, you need to be able to conduct not only direct observations of animals, but also notice all traces of their activity. In the summer, paw prints of animals, birds, etc. It is best to look for it on muddy and sandy shores of water bodies, on roads after rain, or on dusty paths. You need to develop the habit of not leaving without attention a single print, a single trace of the vital activity of animals. The success of field research depends on keen observation.

Methods for counting the number of amphibians and reptiles in nature

The task of quantitative accounting of animals is to obtain data on the number of individuals in the study area or to obtain data on the ratio of the number of main species. The population count is carried out on certain square-shaped areas or counting tapes, and then recalculated per 1 hectare (for small animals) or per 10 hectare (for large animals). The accuracy will depend on the uniformity of the biotope, the nature of the distribution of animals and the ecology of the species.

The methodology for counting the number of amphibians and reptiles boils down to the following:

– on each regular excursion, all individuals encountered in different biotopes are noted for each species separately. At the end of the work, this data is summarized. It should be noted that more accurate data can be obtained if surveys are carried out on a permanent route;

– counts are always carried out during the hours when animals are most active, since this group of animals reacts to changes in temperature and humidity.

Amphibians permanently associated with a reservoir are counted, as a rule, on test plots (area method) established on the shore or in the reservoir. It is advisable to mark the boundaries of the sites with pegs. The total size of the site is 25m2. The number of observations, depending on the required accuracy, should be at least 5–10 times.

With the linear method of counting amphibians, a route of 1–2 km is selected, for lizards and snakes – 4–6 km. The width of the registration tape is chosen depending on the nature of the biotope: a lot of vegetation - 2–3 m; on bare ground - up to 10 m. In the case of a high number of animals, it is necessary to clearly limit the width of the counting route using ropes carried by 2 counters.

Method for studying the daily activity of amphibians

Daily activity is an alternation of periods of rest and activity associated with obtaining food, migrations or reproduction processes.

Amphibians are convenient and easy to take into account on permanent routes. A graph is constructed on graph paper, on which the absolute number of individuals encountered at different times of the day or the percentage of individuals encountered from the maximum is plotted at intervals of 2-4 hours. This gives a clear idea of ​​the nature of the species’ daily activity.

Individuals in water or on land should be separately counted, which gives an idea of ​​both the general activity of animals and their distribution over any territory. At the same time, it is important to monitor changes in temperature and humidity.

Method for studying the nutrition of amphibians and reptiles

With this method, not only the composition of food is studied, but also changes in nutrition depending on various external factors and the condition of the animal itself.

Basic ways to study nutrition:

a) analysis of the contents of the digestive tract (stomachs);

b) analysis of food residues.

The composition of the food of amphibians and reptiles is determined by the contents of their stomachs. Animals are collected along the route. No later than 2–3 hours later, an autopsy of the animal is performed; for this, the contents of the stomach are removed. After removing the food bolus, it is disassembled using dissecting needles. Identifiable parts of the insects are selected and counted. If this is not possible, mark the approximate volume of components on a 5-point scale: 1 point – 0–1%; 2 points – small number – 10–20%; 3 points – significant number – 50%; 4 points – a lot – up to 75%; 5 points – a lot – more than 75%.

Methods for counting the number of birds and mammals in nature

Quantitative bird counts carried out mainly by the route method. The observer counts all birds encountered in the counting strip by voice or appearance. It is advisable to lay survey routes along paths or narrow roads (important during the nesting period). The length of the route in the forest is 500–1000 m; in the steppe 2–3 km. The width of the counting tape is 100 m in the forest and may be larger in open landscapes. The width of the tape is determined by eye (birds located outside the count strip should not be included); counting is carried out preferably in the early morning, and for some species - in the evening (robin).

When counting birds during the nesting period, counting is carried out by votes. It is conventionally accepted that each singing male represents a pair of birds. In addition to singing males, it is also necessary to take into account females by their call signs and indicate them with conventional signs. To obtain reliable data, bird counts along the routes are carried out at least 10 times.

During the nesting period, quantitative bird counts can be carried out on sample plots of 1 hectare (100x100 m) or typical plots limited by fence boundaries.

Having drawn up a plan of the site and its description, you need to find all the nests and put them on the plan, while noting all the birds that fly to the test site for food. The feeding behavior of birds is depicted graphically.

When conducting surveys in the autumn-winter period, the route survey method is used without limiting the detection band. This method is characterized by relative simplicity both in terms of counting techniques and calculating the relative abundance of birds. The records use data from all bird sightings (the field diary records all birds seen and heard, regardless of the distance to them). The result of the census is not the number of birds per unit area, but the relative frequency of occurrence. The usual speed of walking surveys in winter is 2–2.5 km/h, and surveys are carried out in the morning, in the absence of strong wind or snowfall.

Quantitative census of mammals carried out by counting rodent burrows (either on the route or on the site). The length of the route is 2–10 km, the width of the counting tape is 2–4 m. It is important to distinguish between inhabited and abandoned burrows when making calculations. At sites, burrows are counted in the same way, but the size of the sites is 100–250 m2. The shape of the site can be different: square, rectangle, circle.

Method for studying bird nutrition

When studying the diet of diurnal birds of prey, owls, gulls, and corvids, good results are obtained from the analysis of pellets. When studying the nutrition of herons, it is necessary to collect food debris in nests and under trees. To do this, you need to collect leftovers 3 times a day.

To compile quantitative characteristics of nutrition, it is necessary to know exactly the weight of the portion of food brought to the chick at one time. For this purpose, constant monitoring of the nest should be carried out. To fully characterize the diet, it is necessary to know the number of arrivals of parents to the nest per day. For this purpose, daily observations of the nest are organized. Direct observations of chick feeding are very important for establishing feeding intensity in different species at different periods of chick growth. This requires round-the-clock vigil at the nest. The number of arrivals of the male and female with food for each hour should be noted, as well as the beginning and end of feeding should be noted. Weather conditions must be taken into account.

Method for studying bird's nests

Each detected bird nest should be identified, if possible (preferably to species). To do this, it needs to be described and measured: the largest outer diameter, the height of the nest, the wall thickness, the diameter and depth of the tray. If the nest is located on a tree, note the type of tree, the thickness of the trunk, its height, the height of the trunk to the nest, the location and method of attaching the nest, and its exposure to the cardinal points.

For nests located in hollows, measure the diameter of the entrance, note its shape, and the location of the hollow to a rotted branch or tinder fungus. The inside of the nest is inspected using a mirror.

When describing nests located on the ground, they note whether the nest is confined to some kind of shelter (stump, bush, tree, etc.), and the microrelief of the area.

If the nest is in a hole, measure the size of the entrance, the length of the hole, and the exposure of the hole to the cardinal points.

When studying the microclimate of the nest (temperature regime), you should study the empty nest mode to understand its significance. At intervals of 2 hours, measure the temperature inside the tray and outside the nest for a whole day.

From a practical and theoretical point of view, experiments on attracting birds to various artificial nesting sites (lodges, etc.) are very important; carry out planting of trees and shrubs (a method of creating conditions for the settlement of useful and economically important birds).

Method for studying burrows and lairs

Before describing the burrow, you need to characterize the relief, exposure, soil, and type of vegetation. While digging a hole, they gradually take a visual survey of it. The scale is taken depending on the size of the hole, if possible larger. The length of the moves is measured from turn to turn or to branch. For the same points, the depth of their location under the surface of the earth is determined. If the hole being dug is complex and occupies a large area, then it is better to sketch it sequentially in narrow strips separated by twine. When describing nests and burrows of mammals, it is necessary to measure the diameter, wall thickness, determine the size and direction of the entrance holes, the nature of the building material, height and method of attachment. When studying the temperature regime in burrows and nests, in shallow burrows measurements are taken every 2 hours, and in deep burrows a vertical shaft is dug and measurements are taken through a special tube.

A special branch of the study of burrowing activity is the question of the influence of shrews on soil formation. Calculate the number of heaps of earth per unit area and the area covered by these heaps; The piles should also be measured and weighed. To study the chemical composition of the soil, it is necessary to take soil samples from different horizons.