Methods of relative accounting of hunting animals. Abstract: Methodology for field research on the ecology of terrestrial vertebrates Method for studying burrows and lairs
First of all, it is important to establish the abundance of the studied species, the population density, since it is closely connected with the entire ecology of animals and is of versatile theoretical and applied interest.
Without data on the number of species included in the 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, it is impossible to study the dynamics of populations of individual species.
Knowledge of the number of animals is necessary for the correct organization of pest control, in particular, for making forecasts of the mass appearance of rodents; population density has a direct impact on the distribution of a number of epizootics; quantitative accounting of game animals is the basis of hunting management planning.
The main task of quantitative accounting 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 get a really complete picture of the abundance of any species in a given area, but usually the so-called absolute counts give only more or less accurate results. This is not surprising, given the enormous difficulties involved in counting terrestrial vertebrates, which are distinguished by great mobility, caution and secrecy. Even a relative quantitative account of mammals, birds, and reptiles is incomparably more complicated than an account of invertebrates, and even more so of plant objects. This implies the main requirement for any method of quantitative accounting of vertebrates - it must be based primarily on the characteristics of the ecology of the animals taken into account in a given specific situation.
Therefore, quantitative accounting should be preceded by a preliminary acquaintance with the main features of animal ecology and with the biotopes of the study area. The following points are of the greatest importance, as I. V. Zharkov (1939) showed:
1) The nature of distribution by habitat;
2) The tendency to form more or less permanent groupings: 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 clusters;
5) Daily and seasonal changes in activity;
6) Daily and seasonal migrations and wanderings.
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 in advance. However, for any particular group of animals, it is necessary to strive for standardization of accounting methods in order to obtain completely comparable results. Along with the specified requirements, the method of quantitative accounting should provide sufficiently accurate (in relation to the research tasks) results and, moreover, be idle.
Thus, summarizing, we can say that the method of quantitative accounting should be based on the ecology of the considered species, landscape and geographical conditions, season, specific research tasks or economic activities and give, with minimal effort and cost, the most reliable results. Failure to comply with any of the above conditions will adversely affect the work.
There are two types of quantitative accounting of terrestrial vertebrates: 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 counting is determined either by time (an hour, two, etc.) or by a known distance. As for the width of the registration band, some authors do not precisely fix it, but determine it exclusively by the distance at which it is possible to reliably recognize animals by ear, with the naked eye and with binoculars, so that somewhere in the steppe this band is for some species (for example, Meadow chasers or skates) will be equal to a few meters or tens of meters, and for others (large raptors) - hundreds of meters, which is acceptable only when studying and accounting for one species. But more often, the calculation is made at a certain distance from the main line, sometimes more, sometimes less, depending on the nature of the area and species composition. In this last case, we, in fact, get the same areal accounting with the only difference that the accounting area has the form of a strongly elongated quadrangle. Linear accounting, in which the terrain intersects at a more or less significant distance, is often called an ecological section, or, in the terminology of American ecologists, a transect.
When taking into account the areas, a square or other shape and size area is previously allocated on the ground, determined by the species characteristics of animals.
Both transects and plots should be laid out in sufficiently typical and uniform terrain to facilitate the subsequent recalculation of the obtained data for the entire area of the biotope under study. Summarizing the results of counting on heterogeneous sites (including several biotopes simultaneously, which is quite possible in a mosaic landscape) will require some special techniques, which we will discuss below in the section devoted to rodents.
When establishing registration sites, one also has to take into account the fact that even in relatively monotonous biotopes, animals are distributed unevenly. The nature of the dispersion is the more complex, the more complex and heterogeneous the living conditions.
Depending on the ecology of animals, census can be carried out by direct observation (by ear, with the naked eye or with the help of binoculars), by indirect signs (traces, burrows, excrement, pellets, etc.) or, finally, by trapping.
Accounting can cover both permanent groups of animals and their seasonal accumulations, as well as be carried out during seasonal movements.
Data obtained from animal counts, for ease of comparison, are usually recalculated per kilometer (when counting linearly), per hectare or square kilometer (when counting on trial plots). For game animals, it is advisable to take larger areas - 1000 hectares, i.e. 10 square meters. km. The numbers related to this area are called indicators. In the event that accounting data or figures characterizing the number of animals and birds caught are related to the total area of the entire study area or hunting area, then general area indicators are obtained (for brevity, they are denoted 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 for lands (denoted by the same letters, but with an additional sign).
The indicator obtained by dividing the number of animals by a particular area is called the reserve indicator (z and z1). When using the data on the relative accounting of animals by footprints, they are recalculated either per 1000 ha or per 10 km of the way and an accounting indicator is obtained (y and y1). Production indicators are denoted by d and d1 output indicators (i.e. harvesting) - v and v1.
When organizing quantitative accounting and processing the results obtained, one has to operate with quantitative indicators that need not only a biological, but also a mathematical explanation. In connection with the latter, the following considerations of 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 realize what exactly the figures they have received are. From a statistical point of view, any quantitative account (with the exception of rare cases of a continuous, absolute account of all individuals throughout the territory) is a “selective study”: from the “general population” (the entire area, biotope or population), one or more “samples” of that or other size. You can mathematically prove the following statements:
1. The more samples are taken from the total 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 sampling sites 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 indicators obtained, the greater should be the repetition of observations and the number of samples.
5. Mass phenomena and rough dependencies are captured already with a small number of samples and repetitions, and vice versa.
6. The final accuracy of a statistical result depends more on the number of replicates than on the sensitivity of an individual observation. Of course, it is necessary, however, to strictly observe the standard methods.
7. The reliability of transferring the results of sample studies to the general population (“extrapolation”) is the higher, the larger the area or part of the total population was covered by the samples and the greater the repetition.
The exact expression of these dependencies can be derived from the formulas of any course of mathematical statistics.
Novikov G.A.
"Field research of ecology
terrestrial vertebrates"
(ed. "Soviet Science" 1949)
Chapter IV
Quantification of terrestrial vertebrates
Quantitative record of mammals
General instructions
Determination of the number of mammals is carried out in three main ways:
1) By counting animals by direct observations on routes, trial sites or congregation areas;
2) In the footsteps;
3) Trapping.
Depending on the ecology of the species, one method or another is used. Below we look at the most common and practical ways to account for the most important groups of mammals, starting with murine rodents and shrews.
Accounting for murine 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 by direct observations are very limited, and often completely absent. This forces one to resort to all kinds of, sometimes very laborious, auxiliary methods (trapping, digging and pouring out of holes, etc.).
The ecological features of small animals and the nature of their habitats determine the predominant development of relative accounting. Some zoologists (Yurgenson and others) generally consider that an absolute count of mouse-like rodents (at least in the forest) is impossible. However, they are wrong, a continuous count is possible, but only involves a lot of work 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 same requirements are imposed on the choice of trial routes and sites for recording rodents as for birds - they must represent the most typical sites, both in terms of habitat conditions and population of animals. The latter 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, with the wrong location of the sites, their insufficient number or small area, major miscalculations are possible. Sites should not be less than 0.25 ha, preferably 1 ha 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 be related 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 accounting on 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 over the territory, it is quite sufficient to establish the number of individuals per 1 ha of a typical area. But if the landscape is mosaic, with a rapid and variegated change of 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 in nature of various biotopes 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. On the basis of complex accounting sites (i.e., laid down to account for not one, but all types of small rodents. G. N.), the density any species of rodent per 1 ha in these stations is equal to a, b, c, respectively. Out of 100% of this area in nature, stations occupy: 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 the density on the combined hectare Р, equal in our example (after reduction to a common denominator):
P= 4a + B + 5c / 10
Thus, we establish the 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 density, which is usually handled in ecological studies. From this point of view, the use of the concept of a united hectare gives all calculations an incomparably greater concreteness and reality and should be widely used not only when processing the results of accounting on sites, but also on routes, where a change in habitat conditions should also always be noted.
Usually, a quantitative account of small mammals covers all species at once, despite the ecological differences between them. Rall proposes to call such a technique complex, in contrast to species-specific. However, in a number of cases, when it is necessary to study species with specific behavioral features that are not amenable to standard accounting methods (for example, lemmings, steppe lemmings, etc.), then they are specially taken into account.
The most common and well-established method for the relative quantitative accounting of small mammals is accounting 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 accounting, 20 crushers are set up in a straight line, 5 m from one another.
Crushers are placed, as in the case of collecting, under shelters. The standard bait is black rye bread crusts (preferably with butter), cut into cubes 1-2 cm across. Accounting continues for 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 not productive.
In practice, this is determined by the complete absence of prey on all transects.
If the animal is not caught, but the trap is clearly lowered by it (the bait is gnawed, excrement remains), then this one is also equated to the caught specimen and is taken into account in the overall results. To avoid such cases, traps should be alerted as sensitively as possible, but not so much that they slam shut from the wind, a fallen leaf, etc., extraneous light touches. The bait must always be fresh and must be changed after rain or heavy dew; it is advisable to renew the oil daily.
Since the results of accounting to a large extent depend on the operation of the crushers, the greatest attention should be paid to their placement and alerting.
The accounting results are refined with an increase in the number of trap-days. Yurgenson believes that for a complete characterization of the abundance of murines in any forest biotope, 20 tape samples with a total number of trap-days equal to 1000 should be laid.
The results of accounting by crushers on a tape sample are expressed by two kinds of indicators:
1) the number of animals caught per 100 trap-days (indicator of prey),
2) the abundance of all and individual species per 0.1 ha (sample area) and per 1 ha.
Accounting with crushers has a number of indisputable advantages, which provided it with such a wide distribution in various kinds of research. The advantages of the technique include the following:
1) The technique is simple, does not require sophisticated equipment, high labor costs and funds.
2) Crushers with standard bait can catch almost all types of mouse-like mammals, including shrews.
3) Accounting gives quite satisfactory indicators for monitoring the dynamics of the number and comparative assessment of the population of various biotopes.
4) The technique is notable for its considerable efficiency, which provides sufficiently massive data in a short time (with the help of 200 traps, 1 person can get 1000 trap-days in 5 days, which is quite enough to characterize the biotope).
5) A 100 m long tape sample provides data on the relative density of the animal population per unit area and reflects well the average conditions.
6) Accounting is applicable both in the open landscape and in the forest, 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 mined animals can be used for current work.
Along with this, the described method has serious drawbacks:
1) First of all, it is impossible to get some animals 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 affected by the quality of the manufacture of the trap and the personal abilities of the person making the accounting.
3) The same bait has different effectiveness due to weather conditions and the nature of the biotope (availability of food, etc.).
4) Technical imperfection in the design of crushers, sometimes slammed shut not only by animals, but even by insects and slugs.
5) At high population densities and a single inspection of the traps, density indicators are underestimated compared to those found in nature, since a maximum of one animal can be caught in each crush per day. Nevertheless, the relative accounting with crush traps is currently the most accessible and effective, especially in the forest zone.
For quantitative accounting of the water rat, one has to resort to steel arc traps (nos. 0-1), combining captures with direct counts of animals, their nests and feeding tables. Based on the instructions for accounting for 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), the following options for the method of quantitative accounting of the water rat under various conditions can be recommended:
1. Method "trap-linear". Arc traps without bait are placed at all holes of water rats 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 sites). The traps are inspected daily, the caught animals are taken out, the slammed traps are alarming again. The traps stay for several days until the catch drops sharply. The results of catching are listed for 1 km _ of the same type of coastline. An indicator of population is the number of rats caught in a kilometer area.
2. Method "trap-platform". It is used in "diffuse" settlements of the water rat away from the coastline (on sedge tussocks, semi-flooded thickets of willows, cattail, reeds, wet meadows, etc.). Traps are placed on sites of 0.25-0.5 ha at all burrows, on dining tables and at crossings of water rat feeding paths. If there are a lot of holes, their number is reduced by preliminary digging and traps are set only at the opened passages. Catching lasts two days, with a double inspection of traps (in the morning and in the evening). Accounting results are listed for 1 ha.
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-platform technique is modified by setting 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 coast. Recalculation is done for 1 km of the way.
5. In the conditions of extensive settlements in reed and sedge thickets in shallow waters, nests can be counted on sites or ribbons of 0.25-0.5 ha, subdividing nests into brood (large) and solitary ones. Knowing the average population of nests, calculate the number of water rats per 1 ha.
6. In places where nests are hardly noticeable and there is no place to set traps (a lot of water, no bumps, etc.), one has to limit oneself to an eye assessment of the abundance of rats (in points from 0 to 5), counting the number of feeding tables on small areas, belts or per unit length of the coast, and then converting the obtained indicators to 1 km or 1 ha.
In contrast to the method of quantitative counting with crushers, another one is put forward - counting on trial sites using trapping cylinders. Originally developed by Delivron, it was applied on a large scale in the Bashkir Reserve by E. M. Snigirevskaya (1939). The essence of this technique is as follows. In the studied biotopes, three test sites are laid three times a summer, 50 X 50 m in size, i.e., 0.25 ha. Each site is divided into a network of elongated rectangles with side lengths of 5 and 10 l.
For 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. With specially made scrapers, along the lines outlined inside the square and its bounding lines, paths 12-15 cm wide are dug; in this case, only the upper part of the turf is removed, and the bare earth is trampled down. At each corner of the rectangles, that is, at the intersection of paths, a trapping can is dug into the ground. It is more convenient to use Zimmer's iron cylinders with a depth of 30 cm, a width of 10-12 cm, with a socket of 4-5 cm and a perforated bottom for rainwater runoff. Cylinders are made in such a way that three pieces fit one into the other.
Snigirevskaya replaced the iron cylinders with ordinary earthenware jars, which, of course, are much more cumbersome. Krynki or cylinders are dug into the ground slightly below its surface. 66 traps are installed on each site.
Rodents, who prefer to run on paths rather than on grass that impedes their movement, fall into pitchers and most of them die of starvation. Snigirevskaya gives a very high rating to this technique, especially emphasizing that it is possible to get into jugs species that are not caught at all or go very poorly into crushes (wood mouse, baby mouse; shrews accounted for over 60% of all animals caught). Once installed, the trapping banks act automatically, do not depend on the quality of the bait and give a large prey (in three summers, Snigirevskaya caught over 5,000 animals).
However, the method of counting with the help of trapping 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 by Jurgenson (1939) and V. A. Popov (1945). The main disadvantages of the analyzed method are:
1) The large bulkiness of the traps used, especially if clay jugs are used. To deliver them to the place of registration, one has to take a cart, and therefore trial sites can only be arranged near roads, which Snigirevskaya herself (1947) notes and which is in no way acceptable.
2) Establishing a trial plot is very time-consuming, as it is necessary to dig 66 holes, 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 a high standing of groundwater and rocky soil, burying pitchers is almost impossible.
4) The large size of the area and the 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 labor and installation time and extreme bulkiness, 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 rather be recommended for obtaining mass material for biological analysis than for the purposes of quantitative accounting. Our attempt to use it in biocenotic studies in the Les na 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. VA Popov is right when he considers it necessary to simplify the site laying technique.
One of these attempts is the method of counting by trapping trenches in combination with tape trapping with crushers, proposed and tested for 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 agility of animals), with a trench bottom width of 20-25 cm, and surface of 30-35 cm due to the slight slope of one wall of the trench.
When digging a trench, the earth is thrown out on one side, the one that is limited by the vertical wall of the trench. The construction of a trench, depending on the nature and density of the forest stand and the density of the soil, takes from 1.5 to 4 hours. At the ends of the trench, retreating a meter from the edge, they break 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 can be eaten by shrews, reducing the reliability of the count. The trenches are inspected daily in the morning. All animals caught in the trapping cylinders are counted. In this way, it is possible to take into account not only voles and mice, but also shrews, frogs, lizards and insects.
As an indicator of the abundance of micromammalia, we took the number of caught animals for 10 days of trench operation. At each station, we laid two trenches, placing them in the most typical places for the study area, but no closer than 150 m from one another. We consider the work of two trenches within 10 days, i.e., 20 day-tranches, as a period sufficient to obtain an idea of the species composition and relative stocks of animals. If it was necessary to obtain more detailed data on the fauna of the area, we increased the work of trenches up to 20-30 days, and for ecological research we carried out trapping during the entire snowless period.
“This method gives quite objective data, is simple and does not require a highly qualified worker (except for choosing a place for laying trenches).
“The negative side of the method is the difficulty in arranging trenches in places with a high occurrence of groundwater - along the banks of reservoirs, swampy lowlands, alder forests, etc. For a broader characterization of 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 by 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 methods of accounting give fairly close indicators", but, we add, the Yurgenson-Formozov method is incomparably more flexible, operational and applicable in a wide variety of conditions, which cannot be said about the methods associated with earthworks.
Difficulties in direct observation of mouse-like rodents, insufficient objectivity of the results of trapping with crushers involuntarily suggest the idea of finding other methods of relative quantitative accounting and, above all, establishing the possibility of using rodent burrows as a guiding feature. In the steppe regions, burrow counting has found wide application, but in a closed landscape, of course, it cannot play a big role.
Since the burrows of different species of murine rodents are quite difficult to distinguish from each other and are very often used simultaneously by several species, the count of burrows can only give summary indicators of the relative abundance of murine rodents as a whole, without differentiation into species. At most, it is possible to divide holes into small (mouse-like rodents) and large (gophers, hamsters, jerboas, etc.). It is also impossible to judge the number of animals inhabiting them by the number of holes, because one animal usually uses several holes.
Since the entrances to uninhabited minks gradually, within 2-3 months, sink, 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 examination, and by a number of other signs (see above) - select from among the still preserved entrances really inhabited. This makes it possible to use burrow counts for relative counting purposes.
Burrows are counted on routes or on sites. Formozov (1937) recommends conducting route censuses of the number of rodents in the spring, immediately after the snow has melted, in the summer during haymaking and harvesting winter crops, in the fall after harvesting, and in the middle of winter during thaws and fresh snow.
Routes, possibly more straightforward, diverge along the radii from the observation point. The length of each route is up to 10 km, and their total length for each accounting period must be at least 50 km.
Distance is measured by plans, telegraph poles, or by a pedometer.
The width of the accounting strip is taken from 2-3 m, depending on the density of holes and the density of the herbage. To simplify the counting technique, Rall (1947) recommends the use of rope or stick restraints with hanging bars. This device is slowly carried by two workers in front of the counter. With long route counts, the back of the cart on which the counter rides can serve as a limiter.
Routes should evenly cover all critical sites, as is always required in line counting. The directions of the routes are marked on the ground and should 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 counting lines in the previous season. “When taking into account the infestation of crops, in order to avoid damage to the latter, it is advisable to move along roads, borders and outskirts facing virgin lands, fallow and other unsown lands. At the same time, it should be borne in mind that rodents in the fields are especially willing to stay in areas with an undisturbed sod layer (virgin soil, borders, roads) and from here they begin to move, populating crops.
Therefore, the infestation of a crop, taken into account from the boundary or road, will always be higher than the average infestation of the entire area of a given crop. This should be specified in the note to the accounting data. Laying tapes along roads and borders makes it possible to establish the appearance of rodents on crops earlier than this can be done when studying the deep parts of sown areas. Not only burrows are subject to accounting, but also cracks in the soil, which often form in the steppe during hot weather and are readily populated by rodents (especially steppe lemming, herd voles, and others). The population of a crack is determined by the presence of ears of corn dragged there, fresh stems, etc. Burrows are divided into inhabited, or residential, and uninhabited. In this case, the following categories and guidelines can be established:
"one. Inhabited burrow (fresh food remains, fresh droppings, freshly dug earth, traces of urine, paw marks on the dust, a rodent itself is noted, looking out of the burrow, etc.).
2. Open burrow (free passage to the burrow).
3. Burrow covered with cobwebs (often found near recently abandoned burrows).
4. Burrow, partly covered with earth or plant rags.
5. Nora, more than half or completely covered with rags and earth.
It is possible to offer an even more effective way of establishing the habitability of holes, which is widely used when counting in areas - digging holes.
During the count, all minks are trampled or tightly clogged with earth. According to Rall (1947), it is convenient to cover the inlets with lumps or plates of dry cattle manure. The burrow should be closed tightly enough so that the nest is not disturbed by snakes, lizards or beetles.
During precise environmental work, the inlets 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 as 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 minks when counting and processing data, since only by the number of the former one can 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 explore large areas and does not require highly qualified workers, which is why it is accepted by the land authorities.
Accounting for holes on the sites is carried out in the same way as on the routes.
The sites are beaten off with a size of 100-250 square meters. m, but in such a way that a total of 0.25-1 ha was surveyed for every 200-500 ha of the total area of the counting area (Vinogradov and Obolensky, 1932). With uniform distribution of rodents, sites can have the shape of squares, and with colonial (spotted) - more objective indicators give elongated rectangles 2-3 m wide. When counting holes in fields among forest belts, just such sites should be taken, placing them in all 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 the rodents are distributed very unevenly and usually concentrate near tree plantations. Therefore, the distance between the sites on the periphery of the field should be less than in its center.
The method of laying the sites worked out by N. B. Biruley (1934) proved to be excellent: “The trial plot is beaten off in the form of a circle, for which a wooden stake is taken, about 1-1.5 m high. It is hammered in the center of the site chosen for accounting. A ring of thick wire is put on the stake in such a way that it freely rotates around the stake, but does not slide to its base, but is always at a height of 70-130 cm from the ground. One end of the cord is tied to this ring (fishing cord, antenna cord, etc.). 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 the loop. The opposite end remains free. The first rod is tied to the very end of the cord, the second - retreating 3 m into the circle to the next loop.
“When counting, the worker, holding the free end of the cord and holding it approximately at chest height, moves in a circle. The observer, on the other hand, walks beside 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 extreme rod to the next loop and winds the remaining 3 m of cord. So, sequentially, in concentric circles, all holes within the plots are counted.
“As you can see from the description, the length of the cord is at the same time the length of the trial plot radius. Therefore, the desired size of the trial plot is selected by changing the length of the cord. With a cord length of 28.2 m, the circle area is 0.25 ha, at 40 m - 0.5 ha, at 56.5 m - 1 ha, 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 conditions of open steppe, devoid of tall shrubs.
“This method completely solves the tasks. The defined radius of each of the concentric circles automatically excludes the possibility of repeated walking in the same place, without leaving at the same time a missed space. The bars dragging along the ground keep the standard width of the registration strip all the time. The observer only 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 at the same place, the circle requires the construction of one sign, which is easier to put up and then find. With the method of squares, it is necessary to put four signs.
4) Very labor-intensive moments of work, such as marking the sides and corners of the site, placing corner signs, which are necessary with the method of rectangular areas, disappear completely with our method.
Finding and counting holes in the forest is fraught with such difficulties that it cannot be used for the purposes of quantitative accounting, with the exception of certain special cases. For example, D.N. Kashkarov (1945) describes the count of voles (Microtus carruthersi) carried out in the Zaaminsky Reserve by N.V. Minin. These voles dig minks exclusively under juniper crowns. On an area of 1 ha, 83 trees were counted, of which 58 were holes, and 25 were absent.
The average percentage of infection ranged from 64.8 to 70%. The catch for several days under the trees made it possible to approximately determine the number of rodents living there and make a calculation per 1 ha.
We practiced counting burrows on small test plots during biocenotic studies in the spruce forests of the Lapland Reserve.
When working in an open landscape, the method of quantitative accounting by continuous excavation of holes and catching rodents on test sites is very common, which brings us closer to the absolute accounting of rodents. At the same time, this work provides the researcher with massive material for biological analysis.
Burrows are excavated on trial sites. Their number should be such that it covers at least 300-500 holes for each biotope. “Before you start digging out a large complex colony,” advises Formozov (1937), “it is necessary to thoroughly understand the location of individual groups of holes and work according to a well-known system, pushing animals from less complex shelters to more complex ones. In the reverse order of work, when a large group of burrows is first opened, the animals escaping from spare burrows often hide under the layers of earth in a large dug area, which necessitates repeated work in the same place. All groups of burrows are to be excavated in the (accounting) area allocated for work, regardless of whether there are traces of rodents near them or not... center. It can be useful, in order to make it difficult for the animals to run over to neighboring colonies, at the beginning of the excavation, to open all the available passages for some distance before going deeper to the nesting chamber. In place of the exposed areas, it is desirable to leave trenches with steep walls, 10-12 cm high. This is quite enough to delay for some time the run of not only voles or pieds, but even a faster mouse, which makes it much easier to catch animals jumping out of deep parts of the burrow... For each group of burrows opened, the number of passages is counted, and the total count of burrows in the 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 passages (burrows) is given. Each site planned for accounting and excavation must be located within one of any rodent stations ... The pits formed at the site of the excavation are filled up and leveled immediately after the work is completed.
Of great importance when excavating holes is the simultaneity of its implementation. Depending on the hardness of the soil, excavation requires more or less physical labor, but under any conditions it cannot be carried out by the forces of one observer, since it is impossible to dig, catch quickly fleeing animals and keep the necessary records at the same time. “The results of excavation accounting can vary significantly depending on the skill, conscientiousness of workers and the qualifications of a specialist, the ability to look for burrows where animals hide and understand labyrinths. The tearing of each hole must take place under vigilant control, and this complicates the work of the observer in the indispensable presence of several workers ”(Rall, 1936). According to Rall, because of this, accounting by excavation of holes "... is available only in certain circumstances and, first of all, in the hands of an experienced field ecologist who has material resources."
Accounting by continuous digging of holes and catching animals is applicable, except for steppe species, to lemmings. The easiest way is to dig out the holes of the Ob lemming, since in most cases its passages are located in a peat layer, which can be easily dug out with a knife (Sdobnikov, 1938).
During the processing of excavation data, the following points are noted:
1. The total area of the sites surveyed by the excavation.
2. Total number of dug burrows and number of burrows by rodent species.
3. Average number of holes per 1 ha of the most important biotopes; the same for rodents.
4. Average number of holes in a colony or group.
5. Total number of inhabited and uninhabited colonies or groups of holes. The same - as a percentage of the total amount of the studied colonies. (Inhabited are all colonies and groups in which rodents or fresh food remains were found.)
6. Total number of harvested rodents by species.
7. The average number of holes (passages) per one rodent (including cubs).
If for some reason it is impossible to dig holes (for example, on arable land), pouring animals with water is used. For this, it is best to use a large barrel on a cart and iron buckets, and on hiking trails, canvas ones.
V. A. Popov (1944) used for the relative accounting of the common vole - this most massive inhabitant of meadows and fields - its winter snowy surface nests. These almost spherical nests, woven from grass, lying on the surface of the earth, are especially clearly visible during the period of snow melting and before the development of a dense grass cover. Surface nests were counted on routes laid in typical vole habitats. “During the counts, the length of the crossed station in steps and the number of nests found there were recorded. Accounting is best done in pairs. One, having outlined some kind of landmark (a detached tree, a bush, a haystack, etc.), walks in a straight line, counting steps and marking the stations crossed by a recording tape. The second counts the nests and inspects them, reporting the results for entry in a notebook. In order for the width of the counting strip to be constant all the time, the census takers are tied with a cord 20 m long. The length of the counting route should not be less than 3-5 km, i.e. 6-10 ha. As Popov's observations in Tataria showed, the data on counting vole nests are in good agreement with counting them by trapping with crushers. However, counting surface nests is very simple and therefore can be used as an auxiliary method of relative counting of some species of small rodents.
Recently, successful attempts have been made to use dogs for the purposes of relative accounting. They have shown themselves especially well in the tundra when counting lemmings, which, as you know, are very badly caught by ordinary crushers. With some training, the dog not only learns not to eat animals, but even to catch them alive. It is better to lead the dog on a leash, which, although it affects its performance, allows you to observe the known width of the accounting tape. Not only rodents are taken into account, but also those for which the dog hunted, but failed to get. With some skill, you can see by the behavior of the dog what kind of animal it is hunting - for a lemming, a Middendorf vole, etc.
Route tracking with a dog gives the best results in the open tundra, and is almost impossible in dense bushes (Korzinkina, 1946). Of course, this method is very relative and comparable only when using the same dog or when scoring.
Lemmings can also be counted on routes on foot, on reindeer and from reindeer sleds. “Walking through the tundra on foot, the observer notes in a notebook all the lemmings that have run out in a strip 2 m wide. The strip for recording when riding a deer will be the same width. When riding a sled drawn by three deer, the lane width increases to 4 m.
The best results are obtained when working "in clear, calm weather with a 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, visual surveys are carried out and the boundaries of the main lemming habitats are marked, or the distance is measured with a pedometer. The data obtained are corrected by continuous captures on test plots and recalculated for the total area (Romanov and Dubrovsky, 1937).
As an auxiliary means of determining the relative intensity of the migration of Norwegian lemmings in the Lapland Reserve, counting the number of carcasses of animals that drowned in the lake when 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 according to the pellets of birds of prey and owls, proposed by I. G. Pidoplichka (1930 and others), has proven itself well in the steppe regions and has become widespread there. S. I. Obolensky (1945) considers it even the main method of accounting for harmful rodents. The technique is reduced to the mass collection of bird pellets, the extraction of animal bones from them, their identification and statistical processing of the material obtained. Collection can be entrusted to technical assistants. The collection is fast; according to Obolensky, exhaustive material for an area of 200-500 square meters. km can be collected literally in two or three days. At the same time, exceptionally abundant material, numbering many hundreds and even thousands of rodents, falls into the hands of the collector. So, for example, according to the bones from the 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 on pieces of cardboard, all the main parts of the skeleton of rodents of the local fauna in order to have samples for comparison with the bones from the pellets.
If the pellets are collected in a certain area regularly and the places of their accumulation are completely cleared, then by the number of the pellets themselves one can judge the relative abundance of small mammals at a given time. According to the bones from the pellets, the relative abundance of different types of animals is determined. Although small animals become the prey of predators not strictly in proportion to their numbers, but depending on the way the predator hunts, the behavior of the animals and the nature of the habitat, nevertheless, as the observations of both Pidoplichka and Obolensky showed, “... the numerical indicators of the number of different types of animals established according to the number of their bones in pellets, characterize the quantitative ratios 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 both observations of the birds of prey themselves and their relative quantitative count can be used as an indirect indicator of the abundance of rodents, since in general it can be said that the number of both is in direct proportion. Particularly noteworthy are the field, meadow and steppe harrier, short-eared owl, steppe eagle, snowy owl, partly Rough-legged Rough-legged Buzzard and Long-legged 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 to increase their numbers. The abundance of predators during the nesting period indicates that the rodent population successfully survived the critical period of winter and spring; the threat of a sharp increase in the number of rodents becomes real. Finally, in autumn, an increase in the number of predators due to the addition of migrants from neighboring areas to the local nesting ones indicates a significant increase in the number of animals over the summer. In a number of cases, systematic monitoring of predators makes it possible not only to establish the presence of an existing outbreak of "mouse misfortune", but to a certain extent to foresee 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 is dispersed and difficult to count” (Formozov, 1934).
The original method of quantitative accounting using banding was proposed by VV Raevsky (1934). “The method of quantitative accounting we propose,” writes the named author, “is similar to that used in physiology when it is required to determine the total amount of blood in a living organism. So, after inhalation of a certain amount of CO (carbon monoxide - carbon monoxide) or after the introduction of 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 the same way, when we want to determine the number of individuals of any species in an isolated area of observation (island, colony, sharply limited station), we catch some of them, ring them and release them back, moreover, in the following samples obtained by catching, shooting, picking up the dead animals, etc., the percentage of occurrence of specimens noted by us is determined.
“Blood circulation in the body guarantees physiologists a uniform distribution of all its elements, and hence the likelihood that the percentage of impurities in the sample taken will be the same as in the entire volume of the blood being studied. When determining the percentage of ringing by taking a sample from one point, we must also be sure that ringed specimens are distributed fairly evenly in the total mass of the studied population... Such a uniform distribution of ringed individuals in the population that we need is not only possible, but under certain conditions it obviously occurs in nature..."
Raevsky applied his methodology to the study of the ecology of house mice in the North Caucasus, where they accumulate in huge numbers in stacks of straw. Mice are caught by hand, ringed (see below for a description of the ringing technique), and released back. After a few days, n3 is produced; capture, the number of ringed and unringed 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 studied population (N), according to 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 get that the entire population consists of 216 animals:
N= 26 x 100 / 12 = 216
If there were several recaptures, then the population sizes are calculated using the arithmetic mean.
The checks made by Raevsky showed the high accuracy (more than 96%) of his methodology.
“For the practical application of the method of quantitative accounting by banding, you must have the following prerequisites:
"one. Ringing of the species under study should not present too great technical difficulties, otherwise a sufficiently high percentage of ringing will not be ensured.
"2. The researcher must be sure that in the time elapsed from the moment of banding to the sampling, if it is taken from one point, there was an even distribution of individuals within the population.
“3. The animal population to be counted must live in a limited area.
"4. Knowledge of the biology and ecology of the species should enable the observer to make appropriate corrections to the figures obtained (for example, reproduction 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.
In a reconnaissance study of murine mammals, one should not miss any opportunity to characterize the state of their population and, in particular, use an eye estimate of their numbers. Numerous correspondents can be involved in this work, as organizations of the crop protection service and the service of forecasting the number of game animals do with success.
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 counting on tape samples by crushers and with the calculation of residential burrows along the routes.
With visual accounting, the scale for estimating the number in points proposed by Yu. A. Isakov (1947) can be used:
0 - The species is completely absent in the area.
1 - The number of the species is very small.
2 - The number is below average.
3 - The number is average.
4 - The number is high, noticeably above 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 in the snow and dust, food, the number of winter nests that melt out from under the snow in the spring, etc., since together they can give a lot of interesting and important things and it is good to supplement the data of quantitative records.
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 tasks and conditions of work.
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 rather successful approximation to this goal is the method of continuous excavation of 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 by means of their continuous catching on previously isolated sites.
A. A. Pershakov (1934) proposes to lay test sites measuring 10 x 10 m or 10 x 20 m, which are surrounded by two earthen grooves, about 70-100 cm deep and 25 cm wide. The inner slope of the inner ditch is gentle, at an angle 45 degrees, and the outer one is sheer. The outer protective groove has a square section. In the corners of the ditches, level with the bottom, trapping banks break in. The inner ditch serves to catch the animals escaping from the trial site, and the outer ditch prevents animals from entering from outside. In addition to trapping cans, crushers are used and, finally, trees are cut down and even stumps are uprooted. This shows how laborious the laying of each site is. At the same time, it is possible that some of the animals will run away while digging ditches.
E. I. Orlov and coworkers (1937, 1939) isolated the sites with a steel mesh, and then caught the animals with crushers. The site is beaten off in the form of a square or rectangle with an area of 400 square meters. m and is fenced with a steel mesh with cells of 5 mm. The height of the mesh above the ground is 70 cm, in addition, in order to avoid undermining, it is buried 10 cm into the ground. Along the upper edge of the net, a double-sided cornice made of tin, 25-30 cm wide, is arranged to prevent 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 on an isolated trial site is carried out within 3-5 days with crushers and other traps so as not to miss a single animal. The number of traps should be large enough, 80 m, at least one for every 5 sq. m. After the final isolation of the site and the placement of traps, a schematic plan of the site is drawn up, on which burrows, bushes, trees, stumps, numbers of traps are marked, and in the future - places for the extraction of animals (Fig. 73). The trapping stops after nothing has been caught in any of the crushers for three days. Consideration should be given to the possibility of some rodents leaving the fenced area along the branches of trees.
The device of such an isolated platform requires significant material costs (mesh, tin, etc.), and, according to the authors themselves, is a cumbersome and time-consuming task. It takes 30-40 man-hours to lay out the site.
Rice. 73. Schematic plan of an isolated site for recording mouse-like mammals (from Orlov et al.)
Therefore, accounting on isolated sites cannot yet be used on a large scale, but only in special stationary studies, for example, in the study of forest biocenoses, where obtaining absolute indicators is absolutely necessary.
4.2.1. Relative accounting methods
Relative counts are called those as a result of which it is impossible to obtain absolute indicators (density, number). This category may include route registration of animals in the footprints in the snow, an indicator of which is the number of traces of a certain animal species encountered, crossed by the route per unit length of the route (usually per 10 km). Only traces of a day's prescription are taken into account. It is possible, in principle, to count all traces for 2-3 days after the powder has fallen, and then divide their total number by the corresponding number of days. The best way to count only daily tracks is to re-route the route after erasing all the old tracks the day before. The length of the route depends on the size and other features of the surveyed area, the weather and a number of other factors. The passage of the route can be on foot, on skis, snowmobile, dog, reindeer, horse teams, etc. The situation during the passage of the route is recorded with the help of records, voice recorders and other possible means. All observations are recorded: passing landmarks, the time of their passage, the indicator of the speedometer or pedometer, the traces encountered, the type of animals, the observed features of animal behavior, etc. The outline (plan, scheme) of the route with a pencil record is drawn up directly on the route, and when fixing the results of observation in other ways - after the completion of the route accounting (Fig. 2).
Figure 2. An approximate form of the outline of the route accounting of animals in the tracks (according to Kuzyakin, 1979)
It is applied: the route line, the necessary landmarks (numbers of forest quarters, intersections of roads, power lines, clearings, streams, etc.). It is desirable to mark the nature of the land through which the route ran. The main content of the outline is the crossing of animal tracks by the route; the type of beast is usually denoted by an abbreviated letter symbol. The outline also indicates the direction of movement of the animal, and if a group of animals passed in one direction, their number in the group is indicated.
Hunting animals on the route are taken into account mainly by tracks. Accounting for hunting birds, on the contrary, is based on the meeting of themselves.
Accounting and averaging of data by types of land will not be necessary if land types and associated differences in animal population densities are covered by an accounting sample in proportion to the ratio of their areas in nature. This greatly simplifies the processing of accounts. Therefore, when laying accounting routes, the following recommendations should be observed:
Try to lay routes as evenly as possible;
Strive for straight lines;
Do not deviate from predetermined directions;
Do not lay routes along tort roads, rivers, streams, forest edges, borders of different types of forest, along cliff edges, edges of crests, ravines, gullies, i.e. along any linear terrain elements. All of them must intersect with routes perpendicular or at an angle.
One of the best options can be considered the use of a forest block network for laying routes along it. However, it must be borne in mind that the clearings affect the placement of animals, their daily course, and therefore the occurrence of tracks near the clearings. In this regard, it is necessary either to lay routes not along the clearings themselves, but near them, or use sight lines for routes - not cut through the boundaries of quarters and their parts.
Among the relative methods of accounting, a special place is occupied by a group of methods based on counting animals. from one point of view. The most common example of such methods would be accounting of waterfowl at dawn(on bindings). The accountant, being in a certain place with a good overview, counts the flying ducks he sees. In this case, the accounting indicators may be different: the number of ducks relocated (by species or groups) at dawn; the number of flying ducks at a shot distance (up to 50-60 m); the number of all visible and audible at dusk, etc.
Similar accounting method woodcock on traction, which boils down to counting birds: audible (cow, croak), visible, flying at a shot.
It is close to these two methods in terms of execution technique. accounting for large animals in places of their concentration (at watering places, salt licks, feeding grounds, etc.). Animals usually visit such places at night, so the optical equipment of the counter is desirable.
All three of the above methods are united by the fact that in all cases it is impossible to establish the area of land from which the seen, heard birds or animals gather. Consequently, these methods are unsuitable for absolute accounting, they cannot be used in combined accounting, which means that they are purely relative. Such relative indicators can be used to identify the comparative value of a particular hunting place on flights, on draft, on a certain salt lick, watering place, etc.
Another group of methods of accounting is close to the counts at dawn: by the voices of deer and elks on the roar, or marsh and field game from one point. Here it already becomes possible to determine the area on which males of animals or birds cast their vote, which means to obtain an indicator of population density.
Of the methods of relative accounting, which are more often used in combination with other methods, one can name censuses of squirrels and hares by the time when one animal is with a dog (husky or hound, respectively). Purely relative methods are also counts of animals according to their incidence in fishing gear (trap-days). In this case, traps, crushers or other fishing gear are placed in lines at equal distances from each other. The accounting indicator is the number of animals caught per 100 trap-days. If all the prey of game animals goes to receiving points, then the state of the population of the species can be indirectly judged from the data of harvesting. A prey questionnaire can also serve as a method of indirect game counting.
Animal Counting Methods
Methods for counting invertebrates
Collection and accounting of invertebrate animal litter. To collect invertebrate animals of the litter, 1 m2 of litter is measured, the border of the square is marked (with sticks with a cord) and the entire cover is removed, which is then disassembled on a white background (it can be in parts). For each systematic group, biomass is determined (on a pharmacy scale).
For this purpose, the class is divided into 2-4 groups, each of which analyzes individual bedding samples.
Collection and accounting of invertebrate upper soil horizons. To study the invertebrate upper horizons of the soil, test plots 10 x 10 cm in size are laid. After removing the litter, a hole is dug to the depth of horizon A. The raised soil is carefully sifted through an entomological sieve. Found animals are divided into groups, taking into account the number and biomass of individuals of each group; biomass is determined on a pharmacy scale.
Lighter and more accurate methods for accounting for soil and litter mesofauna.
For a more accurate account of invertebrates, litter and soil use methods flotation and dry extraction .
Method flotation boils down to the fact that all (or most) of the invertebrates located in the litter or in the upper soil horizon, when the latter are flooded with a saturated solution of table salt, float to the surface layer of the solution. All emerging animals are collected with a fine-mesh sieve. The procedure is repeated several times until the animals cease to emerge.
Method dry extraction longer in time, but in some cases gives more accurate results. This method is based on the fact that soil animals move to moist areas of the soil, while avoiding drying out. To collect invertebrates by dry extraction, a sample of soil or bedding is taken, placed on a sieve (not very fine) and placed under a metal reflector with a 100 W lamp. Under the sieve, place a tray (with high sides) with a 50% alcohol solution. The distance between the lamp and the sample should be about 25 cm. Every 2 hours, the lamp is advanced to the sample by 5 cm until the distance between the lamp and the sample is 5 cm. The reflector is left in this position for 24 hours. In this case, small arthropods move down and through a sieve fall into a pan with a 50% alcohol solution.
Inventory of invertebrates of the herbaceous layer. To account for invertebrates of the herbaceous layer, the mowing method with a net is most widely used. To do this, you need to face the sun and make 50 double sweeps of the net in one direction or another, but always in a new place, closer to the soil.
Collecting with 50 sweeps of the net during mowing corresponds to the number of animals on a trial plot of 1 m2. The collected invertebrates, together with the label, are placed in the stain. In the laboratory, they are sorted into systematic groups, the number of individuals in each group is counted, and their biomass is determined by weighing on a pharmacy scale.
When collecting invertebrate animals of the herbaceous layer, it is better to divide the class into groups (3-5 people each), each of which collects material in different areas.
To calculate the number of insects per unit area, use the formula:
where R- the number of insects per 1 m2, N is the number of insects caught by the net, D is the diameter of the net (in m), L is the average length of the path passed by the hoop of the net over the herbage at each stroke (in m), n is the number of strokes of the net.
Accounting for invertebrates of tree crowns. To account for invertebrates, tree crowns in school practice are most applicable method of shaking animals from trees.
To collect material, a white sheet (sheet, film) is spread under the tree. Invertebrates that have fallen from a tree are collected in stains (with a 50% alcohol solution), labeled, and sorted into systematic groups in the laboratory. Then their number is determined and biomass is found on a pharmacy scale.
Accounting methods for amphibians and reptiles
The most common method of counting amphibians and reptiles is route accounting method. This method makes it possible to count animals on a certain detection band 100-500 m long.
When accounting amphibians the recorder must move along the coastline, registering animals on a 5 m wide strip (2.5 m in the water and 2.5 m on the shore).
When accounting reptiles animals are counted along the route on a strip 3 m wide (1.5 m to the right and 1.5 m to the left of the counter).
The data obtained, both for amphibians and reptiles, are recalculated per 1 km of the counting route.
Bird count methods
Of all the existing methods for counting birds, the simplest and most accessible in school practice is method of absolute accounting at a constant detection band.
The time of counting birds must be timed to coincide with the period of the greatest "visibility" (the best detectability) of birds of most species in each natural area. Accounting should be carried out in the morning hours in calm weather.
Routes for registration are laid in such a way that they pass through all the most typical biotopes of the given area, with a typical ratio of their areas. The speed of the census taker in forest biotopes should not exceed 2 km/h, in open areas it can be somewhat higher - up to 3 km/h.
The essence of the method of accounting for a constant detection band is as follows. When moving along the route, the counter marks by voice or visually all the birds heard and seen on both sides of the route strip. The strip width for closed habitats, in particular forest ones, is usually recommended at 50 m (25 + 25), sometimes (with sparse herbage and shrubs) - up to 100 m (50 + 50).
One of the mandatory conditions for accounting is the need to record birds only in a dedicated lane. With some skill, the eye measurement of a distance of 25 m turns out to be quite accurate. In order not to re-count the same bird, which was first found in front of the moving counter, and then, when it approached, turned out to be on the side of it, it is better to fix the bird when it is in a conditional sector 45˚ wide from the perpendicular to the direction of the counter. In some cases, it is necessary to record single birds, even if they are found behind the counter.
The reliability of a one-time bird count is on average 70%, that is, approximately 3/4 of the birds living here are detected on the count strip. It should be noted that the singing male is mistaken for a pair of birds.
To summarize the results of the route accounting (finding the density of the species), the formula is used
where R- species density, Q‚ - abundance of species, L- route length, D- route width, BUT- activity coefficient (for forest birds - 0.6, for birds of open spaces - 0.8).
Mammal census methods
At present, among the methods of absolute accounting of small mammals, the most widely used are method trap -lines and method hunters grooves (fences ). The trap-line method is appropriate where various species of mice, bank voles, hamsters dominate, and the trapping groove method - where shrews, mice, lemmings and other small mammals that rarely dig holes dominate.
The essence of the trap-line method is as follows. The counting line should consist of the number of traps (preferably live traps) in multiples of 25, 50, 100, etc. Each trap is loaded with bait and placed in the biotope under study. As a bait, a crust of black bread moistened with vegetable oil is most often used.
Traps are set in the afternoon at a distance of 5 m from one another (7-8 steps) in a straight line. For traps, choose the places where the animals are most likely to be caught (under a lying log, near a stump, near a protruding root, etc.). The traps are checked the next morning. The duration of the stay of traps in the biotope is usually equal to two days. Accounting results are rejected if it rained all night. Short-term and light precipitation are not taken into account.
Abundance is measured by the number of animals caught per 100 trap-days. For example, 200 traps stood in the forest for two days. 28 animals were caught in them. Consequently, 28 animals were caught per 400 trap-days, and 28 animals per 100 trap-days: 4 = 7 animals. For each animal species, the abundance index is calculated independently.
The essence of the method of trapping grooves is as follows. To conduct animal counts using this method, grooves 50 m long, 25 cm wide and deep are used. 5 tin (aluminum) cylinders (cones) with a diameter equal to the width of the bottom of the groove, and a height of 45-50 cm are used in each groove. Cylinders are placed at intervals 10 m, while 5 m remain along the edges of the groove. It is necessary to dig in the cylinders so that their edges are in close contact with the vertical walls of the groove, and the upper edge of the cylinder is 0.5-1 cm below the edge of the groove. When digging a groove, the earth and turf should be taken away from the groove by 10-15 m and put in one place. All animals that have fallen into the cylinders are removed.
The unit of account is the number of animals caught in 10 days of operation of one groove (the number of animals per 10 groove-days).
For an ecological assessment of the structure and functioning of ecosystems, it is necessary to know a number of indicators, which are also determined by statistical methods. These indicators include: species richness (number of species in the community) - S, the Simpson diversity index is D(the more D approaching S, the more diverse the community), the Simpson evenness index is E(the more this index approaches 1, the more evenly all species are represented in the community), the index of similarity between two samples of Sorensen - Chekanovsky - ToS, coefficient of species faunistic community of Jaccard - ToJ, Student's coefficient of reliability - t(differences are considered significant if the value of the coefficient is at least more than 2, but better - more than 2.5).
The Simpson Diversity Index is calculated using the formula
where Ri, - share i-of that species in the total number of individuals of all species.
Example. Suppose that we have found the following species composition in the community under study:
The number of individuals Q | Ri | |||
dragonfly rocker | ||||
grasshopper green | ||||
snail amber | ||||
Bed bug herbal | ||||
Aphid pea | ||||
clover weevil | ||||
Earthworm | ||||
ΣQ = 262 | Σpi2 = 0,2718077 |
Share i-of that species in the total number of individuals of all species is calculated as follows:
where Q- number of a particular species, and Σ Q- the total number of all detected species.
For a dragonfly rocker, for example, Ri = 1 = 0,0038167.
Taking into account these data, we find D(Simpson diversity index). Substituting numerical values into the formula, we get:
D= 1 ≈ 3.67. This means that the species composition of this community
small, uniform.
The Simpson evenness index is calculated by the formula
where D- Simpson diversity index, S– species richness (the number of species found in the community).
Accounts of the number of animals and birds make it possible to find out how many animals and birds are in the land and how they are located in different parts of the economy or the entire region.
The number of animals and birds depends on changes in their habitat conditions. Therefore, accounting work, in addition to accounting for animals, includes the study of changes in their living conditions, the intensity of reproduction, the size of natural mortality in different seasons and years, determining the size of the prey of one or another species of animals from specific areas of land, etc. The collected materials will make it possible to determine harvest rates, predict changes in the number and possible sizes of harvests, study the impact of human activity and environmental factors on the state of the number of a particular animal species, identify the economic efficiency of biotechnical measures, etc. Without exaggerating, we can say that the knowledge of the tracks of wild animals and birds, the ability to read them is the basis for accounting and hunting management.
The primitive hunter recognized the footprints and used this to hunt animals. The study of traces has not lost its significance even now. In hunting farms, an inventory of fauna is carried out on the trail, the success of acclimatization is judged, stocks of animals and birds on the territory of the farm are determined, and the productivity of hunting grounds is assessed.
Many sports and commercial hunting techniques are based on the use of animal tracks. To look for animals, and not to meet them by chance, to be able to find the places of their permanent residence, feeding, rest, the traces left by them help, and therefore the ability to read the tracks is necessary for every hunter, including a beginner.
Traces of animal life are not only prints of paws (legs). These include all the changes that animals and birds make to the environment. In addition to the direct “painting”, animals and birds leave other signs of their presence: nests, burrows and lairs, food remains and excrement, discarded horns, dropped feathers, etc.
The book is based on observations and sketches collected by the authors (Romanovsky V.P., Rukovsky N.N., Karelov A.M., Gerasimov Yu.A., Gavrin V.F. and others) during numerous expeditions to various regions of the CIS countries.
Determining the number of wild animals on the territory of hunting grounds, both assigned to hunting users and free, is necessary to ensure the rational use of hunting resources. Underestimation of the number of wild animals will lead to their underutilization and, as a result, to aimless death from starvation and disease;
There are usually two types of quantitative accounting - absolute and relative. Taking into account that wild animals are distributed, as a rule, over a large territory, are very cautious and lead a secretive lifestyle, it is hardly possible to speak of their absolute count. An absolute record of wild animals can only be applied to large representatives of the animal world (deer, elk, wild boar, etc.) living in a limited, mostly fenced area of a hunting economy, from where these animals have nowhere to run and nowhere to hide.
Even the relative accounting of mammals and birds is rather complicated. Therefore, the registration of wild animals should be preceded by a preliminary acquaintance with the main features of their biology, ecology and habitats.
The following points are of the greatest importance:
1) the nature of distribution by habitat;
2) a tendency to form more or less permanent groupings - herds, flocks,
broods, etc.;
3) the presence of more or less clearly defined hunting areas, overlapping one another, or isolated;
4) a tendency to form more or less regular seasonal clusters;
5) daily and seasonal changes in activity;
6) daily and seasonal migrations and wanderings.
Therefore, the accounting methodology should be flexible for different animals, in different biotopes and different seasons of the year. However, there can be no excessive unification of accounting methods.
Along with the specified requirements, accounting methods should provide sufficiently accurate results and, at the same time, be simple (available for execution).
Quantitative accounting of terrestrial vertebrates can be linear (route) and areal. With linear (route) counting, individuals are counted along a more or less long line, on both sides of it. The duration of accounting in this case is determined either by time or by a known distance. The width of the counting strip depends on the nature of the area and the species composition of the animals being counted. In fact, linear accounting is the same area accounting, with the only difference that the accounting area has the form of a strongly elongated quadrangle.
When accounting for sites on the ground, a square or other shape and size area is allocated, determined by the species characteristics of animals.
Both routes and areas for registration should be established in sufficiently typical and uniform terrain to facilitate the subsequent recalculation of the obtained data for the entire area of the surveyed areas. Accounting can be made by direct observation (with the naked eye or with binoculars), by indirect signs (traces, burrows, excrement, etc.) or by trapping. Accounting can cover both permanent groups of animals and their seasonal accumulations, as well as be carried out during seasonal movements. The data obtained, for ease of comparison, are recalculated per kilometer (with linear accounting), per 100 or 1000 hectares (when accounting for trial plots), of certain hunting grounds.
Almost all accounts can be attributed to the following methods:
1. Route accounting. Used to account for all kinds of animals.
2. Accounting for trial sites. It is applied to the account of all kinds of animals.
3. Salary method of accounting. This method is used to account for ungulates, carnivores and rodents.
4. Accounting run. Ungulates, carnivores, rodents and chickens are taken into account.
5. Accounting in places of winter accumulation. Used to account for ungulates and chickens.
7. Visual accounting of mountain animals. It is used to account for ungulates, rodents, chickens.
8. Accounting in places that attract a large number of animals (salt licks, watering places). The method is used to account for ungulates, sandgrouse, and saji.
9. Accounting for fecal heaps. The technique has been worked out only for ungulates.
10. Accounting for dwellings and nests. This method is used to account for carnivores, rodents, waterfowl and chickens.
11. Accounting for broods. It is used when accounting for waterfowl and chicken.
12. Accounting for the intensity of the flight. Waterfowl are counted.
13. Registration of moulting birds. Like the previous one, the method is used to account for waterfowl.
14. Accounting for nesting sites. Serves to determine the number of predatory, chicken.
15. Accounting for the age composition of the population. Used to account for ungulates and chickens.
16. Accounting with the help of marking and banding. Applicable to almost all types of animals.
17. Air registration. Used to account for ungulates, carnivores, waterfowl.
18. Accounting from a car (motorcycle). It is used to account for ungulates, rodents, carnivores.
Each method of accounting includes, as a rule, from one to several accounting methods, depending on the species composition of the animals being recorded, the timing of the accounting, the type of hunting grounds, etc.
From the whole variety of accounting methods, we tried to choose either irreplaceable under the given conditions (air accounting), or less laborious and easier to use, not requiring any special devices and adaptations that can be performed by hunting management specialists. Description of these methods is given in the relevant sections.
Additional methods for accounting for the number of wild animals include questionnaire registration, accounting for the results of fishing, banding, and filming.
Questionnaire (survey) accounting . There are cases when it is not the specific presence of certain animals per unit area of hunting grounds that is of interest, but the general state of their numbers compared to previous years, or a certain period when the number of animals was known. In this case, the accounting of the number of animals can be carried out using questionnaires that pose questions that need to be clarified. The measure of evaluation in them is the answers: "a lot", "average", "little" or "more", "less". For example, this year there are more or less of these or those animals in comparison with the previous year. Which lands have more animals, and which ones have less.
The assessment of "a lot", "average", "little" is purely visual, but it also allows you to make an assessment of the number. Table 1 is an example of this.
Black grouse abundance estimates
Questionnaire (survey) accounting should precede special accounting. In this case, information is collected about the places of concentration of animals, their approximate number, the location of their holes and shelters, the time of appearance or disappearance, if migratory animals are taken into account. With the help of questionnaires, the distribution and approximate number of rare animals (leopard) or widespread, but difficult to count (wolf) can be studied. Questionnaires are distributed primarily among employees of the hunting economy - rangers, hunters, etc., as they are most closely associated with wild animals, as well as among foresters, hunters and other persons who, by the nature of their activities, are often located in hunting grounds.
Questionnaire records are usually used in special records.
Accounting for the results of fishing (hunting). It has long been known that the higher the number of a hunting animal, the higher its prey (harvesting) and, conversely, with a decrease in the number, the prey also decreases. In this regard, data on the production of game animals can serve as an indirect indicator of the state of their numbers.
The initial data for such accounting can be annual statistical reports or acceptance receipts of procurement organizations (if they are preserved), information received from regional, city
These conditions, along with the search for special rings and marks, make the application of this accounting method extremely laborious and difficult. , district hunting societies and primary hunting collectives, personal data of individual hunters. Taking into account that some hunters are unwilling for one reason or another to report data on the production of game animals by them, anonymous questionnaires should be used to obtain materials in which the hunter does not provide any data about himself (full name, address, etc. .), but indicates only the actual data on the production of game animals.
Of great importance in studying the state of the number of game animals are data on the structure of their populations by sex and age.
First of all, these data are provided by the analysis of used licenses for the extraction of licensed species of game animals, in which there are columns on the sex and age of animals. The creation of standards for horns, fangs and other trophies will be of great help in this. It is more expedient to create such standards in assigned hunting farms for the main hunting objects (deer, roe deer, elk, saiga, wild boar, etc.), by which their sex, age, and time of hunting are precisely known.
Ringing. The release of tagged animals into the land and their recapture to determine the population size has been used for a long time. This method is essentially very simple. It is based on the assumption that the number of ringed individuals caught is related to the total number of ringed individuals in the same way as the number of all taken specimens is related to the total stock of animals of the same species in a given area. From this ratio it is easy to calculate the total initial supply of animals.
This method is used to account for squirrels, moles, birds.
For the application of this method, a number of conditions are defined:
1) catching and ringing of animals should not present any difficulties;
2) the distribution of labeled animals among the populations must be uniform;
3) the population must live in a certain territory;
4) when calculating the total number of animals, their reproduction and
death between captures.
Photographic filming. When taking into account animals that form large herds or flocks (saiga, waterfowl, etc.), photo, video and filming can be of great help in determining their numbers. After the completion of the count, on the received video material, it is possible to calculate the actual number of animals, which in the process of counting could only be estimated by eye. Recording can be done with cameras, camcorders or movie cameras. Shooting from an airplane or helicopter gives the best results. In this case, you can photograph the entire herd or a flock from above, when each animal is distinguishable. Less accurate results are obtained by shooting from a car, since in this case, as a rule, the first row of animals covers the furthest ones.
3.1 Dynamics of the number of waterfowl in the hunting farm "UP ORH Dudarai".
In order to avoid errors in accounting materials, accounting data are summarized for groups of birds that are easily distinguishable in local conditions.
I. Group - mallard. A duck well known to hunters.
II. Group - teals (teal - whistle and teal - cracker) are known to most hunters. Most often, females are not recognized. In this case, the accountant who knows both types of teals well enters his account data in the diary separately in relation to both species, and the one who does not know their differences, but is aware that the birds encountered belong to teals, enters his own. data for the group as a whole.
III. Group - Other river ducks (gray duck, shoveler, pintail). In size, they are close to the mallard, but have a number of differences. If the census taker knows at least one of the mentioned ducks, he should enter the census data accordingly for this species, if he does not know, then the census data are included in the general column "Other river ducks".
IV. Group - diving ducks (red-headed and white-eyed pochard, crested duck, goldeneye, etc.) they are relatively easy to recognize. They differ from the mallard in their smaller size, shortened body, relatively large head, higher landing on the water and rapid flight.
Filling in the credentials is carried out either differentially by species (if they are identified), or jointly for the group as a whole.
V. Group - coot. Hunters know this bird from the shepherd order well. Accounting methods are varied, but you need to choose those that allow you to determine the number of local game before the start of summer and autumn hunting.
The first method is very laborious, but quite reliable. The method is reduced to determining the number of pairs of ducks or geese that are going to nest on the farm. After the spring arrival, most waterfowl break into pairs, some already arrive in pairs. From this moment on, both members of the pair constantly keep close to the nesting site and find themselves relatively easily, since they are not very careful at this time. It should be remembered that counting routes should be tied to areas suitable for nesting, and not on clean water, or counting of arriving flocks.
The second method is to count the broods and adult moulting birds emerging from the thickets to clear water.
The third method of counting waterfowl is the route count of birds, in which the counter passes or floats on a boat through areas typical for nesting, or rather, for the stay of broods of waterfowl.
The best time for surveys is the end of June - the first decade of July. Accounting materials will give a basis to judge how the number of birds has changed compared to the previous year and what is the success of breeding birds in the lands.
Accounting consists in surveying the reservoirs of the farm and registering the birds encountered. At the same time, the number of chicks in broods, adult birds with broods, single adult birds without broods and adult birds that keep in flocks are noted.
The materials brought together by each accountant are generalized throughout the economy.
The optimal time for the opening of the hunt is the one at which at least 90% of the young animals of various species available on the farm fledge.
Nests of waterfowl are becoming more and more pronounced focality, and their total number is sharply reduced. In the European part, the stocks of waterfowl are estimated at 300 thousand breeding pairs, in Kazakhstan and in the south of Western Siberia - at 1 million pairs, and thus are reduced by more than two times compared to the previous period.
3.2 Biotechnical measures aimed at increasing the number of waterfowl in the hunting farm "UP ORH Dudarai".
One of the main activities in the hunting management "UP ORH Dudarai" for waterfowl is the organization of the fight against predators and poaching.
Extermination of four-legged and feathered predators. Wolves and foxes in the region are destroyed by hunting. Stray dogs and cats located on the territory of the farm must be shot all year round.
The fight against birds of prey, in view of their large numbers, must be carried out constantly. The destruction of gray crows (Corvus corone cornis) and magpies (Pica Pika) is extremely necessary in the conditions of the area, since they destroy the clutches of waterfowl in large numbers, as well as black grouse, partridges, and hares. The most effective measure is the shooting of raptors with an eagle owl.
Having studied the literature available to us on the issue of appraisal of hunting grounds, both scientists and advanced practitioners have different opinions, therefore this issue is subject to further study.
To biotechnical measures carried out in the hunting sector " UP ORH Dudarai" also includes controlling the number of predators (especially foxes, goshawks), stray dogs and other predatory animals. This includes monitoring compliance with hunting rules, combating poaching, providing assistance in case of natural disasters, feeding, creating artificial nests in unfavorable time.
Any work to increase the number of waterfowl must be combined with daily activities to exterminate predators. Recently, there has been a need to help birds with the improper use of pesticides and fertilizers, which pollinate crops - the main feeding areas for waterfowl. In some places, poisons that are prohibited for use and most dangerous for game are also used - DDT and zinc phosphide. These drugs are the cheapest, compared with imported ones, less harmful.
Today, not all hunting farms of the region use recreation and rest areas for game. The hunting farm "UP ORH Dudarai" sets the task of protecting game animals and their natural environment as the basis of its activity. Annual production and financial plans of the economy are compiled on the basis of long-term development plans with the inclusion of the following sections:
1. Hunting management - appraisal of hunting grounds, accounting of the number of wild animals, fixing the boundaries of the hunting economy and organizing protection, building bases, cordons and hunting lodges, organizing reserves, establishing the number of hunters, hunting procedures for the local population;
2. Reproduction - determination of annual, seasonal and one-time rates of shooting animals and birds, taking into account their expanded reproduction, the behavior of measures to restore rare species of animals (prohibition of production, feeding)
3. The fight against predators - the complete extermination of wolves, the identification of other types of predatory animals that harm agriculture and hunting, and the organization of their extermination.
4. Combating poaching and fires, staffing hunting inspectors, rangers, proper placement of guards in areas, organizing public hunting supervision, involving schoolchildren and young hunters to participate in the protection of wild animals, rodent control.
5. Organization of subsidiary and auxiliary facilities.
6. Increasing the yield of hunting products, improving their quality and volume of harvesting.
CONCLUSIONS AND OFFERS
Based on the above material, the following conclusion can be drawn. For the successful organization of hunting for waterfowl in the hunting farm "UP ORH Dudarai" of the Akmola district:
1. Accurately and on time to keep records of waterfowl. This will provide information on the state of the game population, determine the optimal percentage of bird removal during the hunting season, so as not to harm the population;
2. to carry out biotechnical measures: first of all, the protection of hunting grounds, measures aimed at increasing the number, which include the fight against birds of prey and predatory animals, the construction of artificial nests, the creation of reproduction sites and ensuring its protection, the creation of shafts, etc.
3. recruit competent personnel, young specialists who will be able to properly organize safe and productive hunting.
LIST OF USED LITERATURE
1Gavrin V.F. Hunting, 1 and 2 parts, Kirov 1970
2 Danilov D.N. Hunting grounds, Moscow, Central Union, 1960
3 Kuzyakin V.A. hunting taxation Moscow, Timber industry, 1966
4Danilov D.N. et al., Fundamentals of hunting management, Moscow, Lesnaya prmyshlennosit, 1966
5 Lee M.V. Hunting grounds of Kazakhstan, Almaty, "Kainar", 1977
6 Shekenov E.Sh. Typology of hunting grounds and hunting management, Astana, 2002
7 Guidelines of the Ministry of Agriculture R.K. "Inter-farm hunting management and biological and economic survey", order dated May 31, 2005 No. 129
8 Guidelines of the Ministry of Agriculture R.K. "Conducting on-farm hunting management", order dated May 31, 2005, No. 128
9Durasov A.M., Tazabekov T.T. Soils of Kazakhstan, Almaty, 1981
10Grabarov P.G. The content of humus and nitrogen in relation to carbon to nitrogen in the soils of the KazSSR, Izv. AN KazSSR, vol. 2, 1960
11 Durasov A.M. Soils of Northern Kazakhstan, Publishing house - in KazGU, 1958
12 Ministry of Agriculture of the Kazakh SSR, Recommendations on the system of agricultural management, Tselinograd region, Almaty, 1982
13 Dobrokhotova K.V., Pisarev A.A. Healing plants around us, Almaty, "Kazakhstan", 1980
14 Egorov V.I. Registration of hunting animals and birds, Astana, 2002
15 Shtilmark F. Rohota and nature conservation, part 1, Moscow, 1983
16 Gileeva A.M., Kurok M.L. Environmental Protection, Moscow, 1983
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