Extermination of animals: causes and consequences. Influence of wolf predation on the age and bottom structure of wild ungulate populations

ASTRAKHAN BULLETIN OF ENVIRONMENTAL EDUCATION

No. 2 (18) 2011. p. 165-167.

UDC 591.5-599

ECOLOGY OF THE WOLF

Karpenko Nina Timofeevna

State natural reserve "Bogdinsko-Baskunchaksky" [email protected]

Key words: Wolf, taxonomy, history, origin, morphology, ecology, human relation to a predator, hunting, extermination, population regulation, the role of the wolf in the biocenosis

Abstract: The article analyzes data on the ecology of predatory mammals. The author considers various opinions and justifications for the role of the wolf in ecosystems, regulation of its numbers, and gives recommendations for determining its status in reserves.

ECOLOGY OF A WOLF

Karpenko Nina Timofeevna The state natural reserve "Bogdinsko-Baskunchak" [email protected]

Keywords: Wolf, systematization, history, an origin, morphology, ecology, the relation of the person to a predator, hunting, destruction, regulation of number, a role of a wolf in a biocoenosis.

In article the data on ecology of predatory mammals is analyzed. The authors consider various opinions and substantiations of a role of a wolf in ecosystems, regulations of its number and are made for the definition of its status in reserves recommendations.

The wolf Canis lupus is a representative of the order of carnivores, the canine family. In historical times, among terrestrial mammals, the range of the wolf occupied the second place in terms of area after the range of man. Modern wolves descended from carnivorous predators that lived 100 million years ago, and about 20 million years ago dogs originated from the wolf. The genus of wolves is one of the most common among land mammals, but the smallest. It has only seven species: the wolf (Canis lupus); common jackal (Canis aureus); coyote (Canis latrans); red wolf (Canis rufus); black-backed jackal (Canis mesomelas); striped jackal (Canis adistus); Ethiopian jackal (Canis simensis); wild and domestic dogs, as well as all foxes, arctic foxes, raccoon dog and maned wolf.

The wolf is a legendary animal. It has a body type that is adapted to long-term pursuit of prey over long distances and brought to perfection in a predator. This is a predator with a highly developed psyche and strong communication abilities. It is characterized by great mobility of the facial muscles: its facial expressions are rich and expressive. He is able to analyze the situation, draw certain conclusions, predict events, and quite easily adapt to changing conditions. The word "wolf" in the Indo-European languages ​​​​appeared about 7 thousand years BC. Ancient people did not distinguish themselves from the surrounding nature, because they did not see the difference between themselves and animals. From time immemorial, the beast lived next to man, in the same ecological conditions, hunted the same prey as man, and was both an ally and a competitor for ancient man. Wolves and primitive people, at first, had much in common in behavior, the same problems. But as civilization developed, the wild wolf was turned by man into a symbol of evil, into a sworn enemy. For many nationalities, the word "wolf" has become a household word, and the wolf itself has become a totem animal. People associated the beast with dark forces (demons of darkness, werewolves) and with cold (the Bulgarians called the winter months "Velchi holidays"). They believed that animals not only understand human speech, but can even take revenge on humans. Thus, the well-known Georgian biologist Badridze Ya.K., who has devoted more than 30 years to studying the wolf population, is convinced that in close contact with animals, a person develops those feelings that are no longer needed due to the development of speech. “I am sure that wolves are able to convey information with their eyes. They all have telepathic abilities ... ". The commonwealth of a man with a wolf has been firmly preserved for many millennia. People and wolves, following each other, help to find prey and cope with it. According to modern hypotheses, people at first used the remnants of the predator's meal, and if they were lucky, they took it away from him. The disruption of this evolutionary balance occurred relatively recently, when people moved to intensive domestication of wild animals, which became more accessible prey for the wolf than in the wild. This led to him becoming a competitor of man,

and as a result - its mass extermination in the developed territories. By exterminating a predator, people do not understand that they are thereby violating natural ecological ties and that it is much more difficult to return animals raised in captivity to their natural environment. Since they are practically not adapted to life in the wild, of which they themselves are a part. Captive-bred predators often become easy prey for hunters and poachers, as they trust a person and let him close to him. But even in animals raised by people, there is no understanding of who can be hunted and who is not, since the process of taming a predator weakens passive-defensive reactions and increases aggression, and therefore the wolf begins to cut livestock because it is an easier prey for him. .

The wolf is a typical large predator with a wide range of food. Although ungulates are the main food everywhere, it can also catch fish, frogs, mice, and destroy bird nests. Pieces of chitin from dark beetles, locusts, green parts of plants, undigested shells of watermelons, tomatoes and melons are constantly found in the excrement of wolves. A number of plants that grow in the reserve, the wolf uses as a complete food: blackberries, rose hips, silver sucker, fruits of wild fruit trees. Wolves are also characterized by cannibalism, and carrion is one of the most important food sources for it. Interestingly, when new types of prey appear, the wolf sometimes does not dare to touch it for a long time. Thus, not a single case of a wolf attack on a wild boar, noted relatively recently in the reserve, has been recorded in the reserve. The wolf is the most social hunter in the canine family, as it is born and lives in a pack that constantly lives in the same territory. However, there are animals that are not part of packs, they are sometimes called "non-territorial". This is a population reserve. In areas where the extermination of wolves is ecologically justified, these loners should be removed from the populations in the first place. They are the most likely hunters of domestic animals. But biologists still cannot explain how and on the basis of what instinctive behavioral reactions hunting behavior is formed. It is also unclear at what stage of ontogeny certain elements of predatory and hunting behavior develop. In winter, and especially in late autumn, when adults pass on experience to young wolf cubs, wolves slaughter livestock, moreover, they slaughter more than they can carry. The modern development of animal husbandry has led to an increase in the number of livestock, therefore, the predator has an additional source of food. This is another strong argument for regulating the number of the beast. In those areas where the wolf causes significant damage to livestock, it is subject to partial shooting, but the complete destruction of wolves is highly undesirable.

All species have the right to life, and in relation to animals that cause damage to the economy or human health, measures are recommended to limit their number and distribution. The wolf, just, belongs to the number of species requiring constant human control. Knowledge about the wolf in our country is the result of hunting experience, which explains many features of the behavior and biology of the animal. Wolf hunting is one of the most intense, most exciting sport hunting. The whole history of Russia testifies that it was the wolf that was and remains the traditional Russian object of hunting. This knowledge is of great importance for hunting practice, but is not always suitable for wolf population control in modern conditions. It will not be entirely correct to limit oneself to attention to the wolf as a pest of the hunting economy. The wolf deserves serious attention as a species that plays an important role in biocenoses slightly modified by human activity, which are modern nature reserves.

The lack of knowledge about the ecology of this predator limits the ability to maintain its population at a safe level. Opinions of zoologists differ on the issue of controllability of the wolf population: some believe that one should look at the predator “through the slit of the sight”, destroy its lairs, get it with the help of traps, poisoned baits, raids, extermination techniques (helicopters), the majority still insist on the need for in-depth research to manage this species. It should not be forgotten that the wolf is not only the main cause of individual death of herbivorous animals, but is also a regulator of the ecological and physiological well-being of populations. One cannot say about the wolf "forest orderly" in the philistine sense of the word, since it kills not only the weak and sick, but the healthy and strong.

Modern methods of study, including radio telemetry, aerial observations, biochemical analyzes, questionnaires, have proved the necessity for the presence of a wolf for the population of ungulates, that is, they have revealed its useful role. But one should not fall into complacent ideas of protecting the wolf either, since this can lead to an uncontrolled increase in the number of predators. Of course, it is very difficult to manage the numbers in the lands where the hunter and the predator are in charge. Perhaps the most acceptable in this regard are reserves, where the relationship between ungulates and wolves is close to natural.

To reveal the role of a predator in biocenoses, especially in territories that are little subject to anthropogenic influence, which are nature reserves, is one of the main research tasks in the reserve, since predatory animals play an important role in the functioning of the protected ecosystem and are an integral part of it, an important link in the trophic pyramid. The stay of a wolf in the reserve should be considered as an opportunity for the conservation of this species (with intensive destruction of it around) and as an element of the necessary functioning of a protected ecosystem. “If we want to have reserves of the type of nature standards, we must refuse to regulate on their territory all kinds of animals, in

including the wolf. Otherwise, we must once and for all say goodbye to the idea of ​​preserving absolute natural reserves” (Gusev, 1978 p. 27). In the reserve "Bogdinsko-Baskunchaksky" the number of wolves is relatively small. For the reserve, this is a common and permanent species. Permanent lairs of wolves are noted in the Green Garden and in the area between the Gorka River and the Green Garden, as well as in the Sharbulak tract. In summer and early spring, wolves live throughout the entire territory of the reserve, in winter they tend to places of concentration of ungulates and areas of slopes that are warmest during the day. An analysis of the distribution of wolf tracks in winter showed that the territory of the reserve and its buffer zone are visited by wolves fairly evenly. The relationship of the wolf with ungulates and other mammals is close to natural, contrary to popular belief that where the wolf appears, the foxes disappear there. Wolves do not pose a threat to game in the reserve either. It can be assumed that the presence of wolf families scares off the saiga, and he began to visit the reserves less often. Therefore, there is no particular reason to consider it an absolutely destructive element. Still, it is necessary to note the negative facts of the presence of predators in the reserve. In November 2004, wolves killed a cow on the territory of the reserve, and in March 2005, one wolf was forced to be shot.

In order to find a compromise in the heated discussion of assessing the role of the wolf in ecosystems and to determine its systematic status, it is necessary to: form data characterizing its abundance,

spatial distribution depending on the phase of its biological cycle; improve the method of field observation; make a rationale for the most acceptable ways to regulate the number of wolves; determine the real damage to the number of ungulates. It should be noted that due to the fault of the wolf, not a single species has not only disappeared, but has not even become endangered. Entry into the Red Book of wild ungulates is the result of human activity, poaching. Only on the basis of the results obtained can one prove the negative role of the predator in the existing population. The supporters of the complete extermination of the wolf were very accurately answered by the Russian scientist A. Sludsky: “At present, we cannot fully assume the functions of natural selection, they, as before, must be carried out by predators, it is impossible to completely destroy them as a species under modern conditions.”

Literature

1. Chronicles of the nature of the "Bogdinsko-Baskunchaksky" reserve for 2001-2011.

2. Amosov P.N. Fauna of vertebrate animals of the reserve "Bogdinsko-Baskunchaksky"; Volgograd, Tsaritsyn, 2010. - 92 p.

3. Arnold O. Life among wolves. Ecology and life 2011.-№7 P.91-96.

4.Badridze Ya.K. Wolf 1. Some data on the formation of the hunting behavior of wild wolves. Tbilisi, Metsniereba, 1996.-17p.

5. Bibikov D.I. Wolf. Origin, systematics, morphology, ecology. M., Nauka, 1985. -609 p.;

6. Interview with D.I. Bibikov "What to do with the wolf?". www.kindvolk.ru

7. Formozov A.N. On the reaction of the wolf (Canis lupus L) to humans. The behavior of hunting animals. Collection of scientific and technical information. Issue 51-52. Kirov, 1976.-S.84-85.

Wolves life

The organization of some animal families is more complex than people are usually used to realizing. Wolves have a so-called "big family", the meaning of its orders, biologists have figured out only recently. Having matured, strong young wolves (two-year-olds and three-year-olds), having chosen a girlfriend to their taste (often for life), leave the pack in the spring and start their own family. Their weak peers are less happy, they usually do not live in their own home, they do not know marriage (if there are strong wolves in the district). They are "hired", as they say, as nannies to their brothers. Such is their fate. The mothers allow the young to settle somewhere nearby, two or three kilometers away. This is very kind of them: usually the nearest den is seven kilometers from den to den.
And family life begins. Actually, it begins, perhaps, earlier, a year before. Partners choose each other when they are still considered profitable: rather awkward, funny, but, as expected, pretty "boys" and "girls".
A whole year of mutual courtship. Wolves, as they say in science, "facial orientation." From snout to snout, they receive information about what they intend to do, and whether, in particular, the she-wolf is ready to become a mother, and the wolf a father. Only then does mating take place. And before that, and along with that, a fan of smiles, acrobatic jumps, various frisky undertakings - all for a sweetheart or for a sweetheart. By the way, among wolves, the division into “weak” and “strong” sex is not very noticeable in the sense that one should try with might and main, and the other only coyly accept courtship.
The emergence of a "triangle" very often ends in tragedy. A fight, a quick jerk of terrible teeth, and one of the rivals (or rivals) is defeated. And these are the very animals that rarely fight, whose quarrels are rare. But here the harsh laws of natural selection are at work.
When the cubs are born, the mother lies with them in the den for the first weeks. Then, sniffing, it carefully crawls out of the hole, but does not go far, only a hundred or two hundred meters. Somewhere here, members of the "big family" bring her prey: everything that they caught. Later, she herself prowls around the area. And then the nannies - "aunts", "uncles", "cousins" - nurse the wolf cubs. They play with them, feed them with meat swallowed during the hunt, and, of course, keep a watchful guard. The wolf-father also does not forget his duty. He is always there (unless he left with the she-wolf). And in the fall, when the kids grow up, the wolf "big family" hunts in a pack, and the young learn from the old laws of the jungle.

The role of wolves in nature

Alaska, tundra. Thousands of migrating deer. And the wolves are not far away. Two rushed after the herd - straight, very frisky gait. The herd does not doze, it rebuilds on the move, but does not change direction, it stretches. Hooves thump louder, and excitement runs through the thicket of deer antlers. No, the wolves cannot catch up with them. Even thin-legged, fragile fawns run faster. Convinced of the futility of the chase, the wolves quickly fall behind - why waste energy?
But here is another group of deer. Again a swift wolf raid, again the same reaction of the persecuted - and suddenly ... The flowing mass of the herd seems to squeeze a drop out of itself - a limping, shaking head male. His comrades quickly move forward, and he delays something, and the wolves overtake him.

If we make an examination, we will find the following: the front hoof of the deer is missing: instead of it, rags; the lungs are infected with tapeworm and already half destroyed; the intestines are eaten away by phenol and indole, poisons of intestinal microbes; a heart...
You may not continue. Any of these diseases is enough to consider the deer doomed.
Suppose a sick deer were left to live: he is a walking hotbed of infection. He will find a female, and then a deer was born to them with a heredity that is not resistant to diseases. It will grow up and also bring a sickly deer... This is how deer herds die out, and scientists used to shrug their shoulders: why is that? Now it is clear to many why.

In Alaska, in the Nelchinsky Reserve, all the wolves were killed. Four thousand deer found peace, and ten years later there were 42 thousand. And ... a huge herd, having eaten and trampled all the lichen on pastures, began to die catastrophically quickly. I had to call on the help of wolves, from the position of "outlaws" they were transferred under his protection.
The wolf is the chief curator of the forest, tundra, and steppe. If there are no large animals, he eats small rodents - agricultural pests. Again, the benefit of the wolf! He catches pike in the spring in the canals, and sometimes he even has to eat berries and ... insects. Undemanding beast.
Predators, one might say, improve the situation in the forest. Therefore, now in many African countries, the leopard, and in some places the crocodile, are taken under the protection of the law. The leopard is useful in that it exterminates wild pigs and monkeys that devastate the fields, and the crocodile - half-dead fish that carry the infection, harmful insects and crustaceans. “But, unfortunately,” African zoologists write, “crocodiles sometimes attack people as well.”

The impact of the wolf on agriculture

Agriculture is the foundation of any society. It has been small for centuries. To take away a sheep, a cow and a horse from a peasant means to put him in the face of starvation. This is how the wolf becomes the killer of man. That situation is irrevocably a thing of the past. Wolves, on the other hand, still attack domestic animals and are cruel: instead of one sheep, which they can carry away, they drive and slaughter a dozen on the run. Some attribute this to the wolf's nervousness caused by the presence of a human. Some - his character: he simply can not resist the extermination of the weak. But the matter is simpler: people will not collect all the slaughtered sheep lost in the forest, and then the wolves will find them under the snow and will be full for a long time. Nowadays, a large livestock farm is almost guaranteed against attack by wolves, even if they are nearby.

“If you examine the diet of several coyotes, it turns out that they killed poultry and livestock to the amount of N rubles. For the rest, their food consisted mainly of mice and rats, which, if they had not been eaten by wolves, would have destroyed grains worth N x 1.3 rubles. The conclusion seems to be clear: thanks to a few wolves, we made a profit.” Many researchers now say that it is wrong to divide wild animals into good and bad, useful and harmful.

In nature, a natural balance has been established between different species of animals and plants over millions of years of their joint existence. The reckless destruction of various animals and birds can upset this balance, and then other animals and even plants will begin to die, pests and weeds will multiply. In a word, the consequences can be very bad.

Diseases carried by wolves

Wolf hunting

Once upon a time, a huge territory, the entire neo- and palearctic with the countries adjacent to the south right up to Israel, Iran and India, abounded with wolves. A lot of cattle, and a lot of people died under their teeth. Cities, villages and entire tribes sometimes united together, arranging raids on wolves, in which thousands of beaters, spearmen, and crossbowmen took part.
The cantons of Switzerland still maintain, of course, now only traditional and useless wolf hunter societies. And in England, it seems there is still (or until recently there was) the position of the chief of the king's chief of wolf rounds, although the last wolf was killed in Great Britain in 1680 by a certain Cameron Lokiel. The last wolf of France fell near the borders of Switzerland, near the city of Morestel, relatively recently (wolves apparently run into this country from time to time from the Pyrenees and Apennines). On the Morestelian wolf, on an area of ​​50 square kilometers, a grandiose, downright imperial raid was arranged: two thousand beaters, a thousand hunters, three aircraft and 60 gendarmes with radio equipment!

There are no more wolves in France. They survived in Western Europe only in Spain, in the Apennines, Sicily, Scandinavia,
Germany, and further - everywhere in the east to Chukotka, Sakhalin and the island of Kunashir in the Kuril archipelago. And in the direction of the meridian - from the shores of the Arctic Ocean to the Crimea and the Caucasus inclusive. In India, wolves are still found, but, apparently, only in the Himalayan foothills and mountains. In North America, gray wolves live in Canada, Alaska, Greenland, and in some regions of the United States bordering Canada. True, in the south of this country, in the states of Texas, Louisiana, Arkansas and Missouri, black wolves of the same kind come across, but of a different species than gray wolves, and smaller than them.

Introduction

CHAPTER 1. NATURAL-CLIMATE AND SOCIO-ECONOMIC CHARACTERISTICS OF THE TERRITORY OF THE PRI-BAIKAL NATIONAL PARK 25

Chapter 2

2.1. Morphological features and systematic status of the wolf in the Baikal region 35

2.2. Condition and transformation of habitat 44

2.3. Spatial distribution 58

2.3.1. Hunting area size 63

2.3.2. Distribution by land during the year depending on the phase of the biological cycle 67

2.3.3. Stationary placement 82

2.3.4. Dynamics of territorial distribution 98

2.3.5. Adaptive response of the wolf and its main food objects in the zone of industrial transformation of lands... 103

2.4. The structure of the diet of the wolf 123

2.5. Sex and age structure and population dynamics 142

2.5.1. Population dynamics and factors influencing it.. 155

CHAPTER 3. THE WOLF IN THE BIOCENOSIS OF THE PRIBAIKAL NATIONAL PARK 166

3.1. The influence of wolf predation on the age and bottom structure of wild ungulate populations 169

CHAPTER 4. CONTROL AND REGULATION OF THE NUMBER OF THE WOLF IN THE PNP 182

4.1. Assessment of environmental and economic damage 188

4.1.1. The amount of food eaten 188

4.1.2. Methodology for assessing environmental and economic damage ... 194

4.2. Improving accounting methods 197

4.3. Justification of ways to regulate the number 202

4.4. Organization of measures to optimize the number.209

CONCLUSIONS 216

REFERENCES 218

APPS 239

Introduction to work

Relevance of the topic. The problem of managing populations of wild animals, including the wolf, and determining the role of this predator in biocenoses, especially in areas that are little subject to anthropogenic influence, is one of the main tasks of modern science and practice for Russia, since, despite the intense persecution by humans, The damage to the national economy still reaches tangible proportions in many regions of our country, and a noticeable decrease in its livestock, despite the huge funds spent on this struggle, is not observed.

At the present stage, the relevance of solving these issues has increased significantly, due to the fact that Lake Baikal has been declared a world heritage site by the world community. This, in turn, put forward new requirements for the conservation of landscape and biological diversity, for the study and management of wild animal populations in accordance with the modern strategy for the rational use of natural resources.

A significant number of publications of a number of authors are devoted to the study of the ecology of the Eastern Siberian wolf: V.V. Kozlova (1955), N.V. Rakova (1975), E.I. Gromova (1977), V.P. Makridina et al. (1978), SP. Kucherenko (1979), B.P. Zavatsky (1982), M.N. Smirnova (1984, 2002), N.K. Zheleznova (1983), M.D. Ippolitova (1983), V.V. Nesterenko (1989), S.A. Somova, V.A. Vlasova (1996), V.N. Stepanenko (1996) and others. However, to date, its role in the biocenoses of Siberia and the Far East, including the Baikal region, and in particular in specially protected areas, such as the Pribaikalsky National Park (PNP), has not been clearly defined.

At present, there is a steady growth trend in the number of this predator in the NNP, which has led to an increase in its pressure on the populations of wild ungulates, attacks on livestock have become more frequent, etc. AT

In connection with this, there is an urgent need for an immediate solution to the problem of regulating the number of wolves, the effectiveness of which largely depends on conducting comprehensive studies to study the ecology of this species.

Based on the above, purpose The purpose of this work was to study the ecology of the wolf in the conditions of specially protected territories on the example of the Pribaikalsky National Park and the development of measures to regulate its numbers.

To achieve the goal, the following tasks were set:

Establish the systematic status of the wolf living in the territory
rii of the Baikal region;

to study the ecology, condition and spatial distribution of this predator in the study area;

to identify the features of long-term population dynamics and structural and population characteristics of the wolf;

assess the ecological and economic damage caused by this predator to wild ungulates and determine its role in the biocenoses of the park;

develop a set of measures to control and regulate the number of wolves in the PNP.

Basic provisions for defense. 1. According to the morphometric parameters, the wolf inhabiting the territory of the Baikal region should be attributed to the subspecies of the Siberian timber wolf Canis lupus Altaica, L., 1758.

2. The dynamics of the spatial structure of wolf populations in the PNP depends on the phase of the biological cycle and the currently existing natural-climatic, physical-geographical and socio-economic conditions that affect the distribution of the main objects of wolf feeding on the territory of the PNP.

The dynamics of the number of wolves and wild ungulates in the NNP is characterized by the presence of periodic cyclicity with a steady upward trend in the number of this predator.

At this stage, with the existing size of the population, the negative role of the wolf in the biocenoses of the Baikal region has been established, which requires the development of immediate measures to optimize its numbers.

Scientific novelty. For the first time for the Baikal region, comprehensive scientific studies were carried out to study the ecology of the wolf (for example, the Pribaikalsky National Park), the systematic status of the PNP wolf was determined, and an extensive array of long-term data was formed that characterizes the dynamics of its abundance, spatial distribution depending on the phase of the biological cycle, and the structure of the diet etc. An improved methodology for carrying out accounting work has been proposed, a rationale has been made for the most acceptable methods for regulating the number of wolves in the conditions of the Baikal region, and the real and potential damage caused to them by wild ungulate PNP has been determined. On the basis of the materials obtained, the negative role of this predator in the biocenoses of the park was proved, given the existing size of its population.

Theoretical and practical significance. AT As a result of the research, new information was obtained characterizing the state of wolf populations and the extent of the impact of its predation on wild ungulates in specially protected areas (for example, PNP), the concept of the negative role of the wolf in biocenoses was formulated and substantiated. The results of the research can be used in the educational process in the training of students-hunters and ecologists, as well as in organizational and production structures involved in the rational use of wildlife resources and environmental organizations. They should also be taken into account when developing a strategy for the rational use of wildlife and conservation of landscapes.

th and biological diversity.

Practical implementation of research was embodied in recommendations for conducting censuses and implementing measures to regulate the number of wolves, as well as their implementation in the production and environmental structures of the PNP and the Baikal region.

Approbation of work. The main results of the research were reported at the conference dedicated to the 65th anniversary of the Irkutsk State Agricultural Academy (1999), the conference dedicated to the 50th anniversary of the Faculty of Game Science (2000), at the 1st scientific conference "Results and prospects for the development of the theriology of Siberia", held by the Theriological Society of the East Siberian Branch (2001 2001), three regional scientific and practical conferences (2001, 2002, 2003), at the conference "Baikal World Heritage: Economics, Tourism, Ecology 2001" (September 11-14, 2001).

Publication of research results. Based on the materials of the dissertation, 15 works were published.

The structure and scope of the dissertation. The dissertation is presented on 256 pages of typewritten text and consists of an introduction, 5 chapters and general conclusions, a list of references, including 169 domestic and 15 foreign sources, 8 appendices. The text is illustrated with 62 tables and 21 figures.

Condition and transformation of the habitat

The habitat is composed of many elements of inorganic and organic nature and elements introduced by man, his production activities (Radkevich, 1983). By the nature of the habitat dynamics, one can judge the degradation or increase in reproductive parameters and the state of game animal populations, as well as assess the degree of variability of the entire natural complex (Naumov, 1981).

As of January 1, 2002, the area of ​​land of the ENP was 305.297 hectares. of which the forested area - 92.5%, non-forest lands - 6.7%, they are mainly represented by swamps, pastures, hayfields, clearings and roads (1154 hectares or 0.4% of the forest fund), their presence greatly facilitates the movement of wolves in winter period. Other unused lands amount to 12319 ha or 4% (Table 17).

At present, the following categories of lands have been identified on the territory of the PNP: forest lands occupy 92.7% of the total area of ​​the park, agricultural - 1.4%, water - 0.11%, wetlands - 1.35%, other lands - 5.13%. The area of ​​forest lands is distributed as follows: light war - 58.34%, dark coniferous - 9.11%, deciduous - 23.94%, Siberian stone pine - 0.84%, burnt areas - 0.22%, cuttings - 0, 25%. Water (rivers, lakes) make up 0.113%, swamps - 1.35%, arable land - 0.017%, pastures - 0.414%, hayfields - 0.28% of the total area of ​​hunting grounds (see Table 17).

In the forest fund of the PNP, the area is distributed by species as follows: pine grows on an area of ​​145,067 ha (51.4%), birch - 51,096 ha (18.1%), larch - 33,051 ha (14.7%), aspen - 23,232 ha (8.2%), cedar - 22,285 ha (7.9%), spruce - 2,834 ha (1%), fir - 2,032 ha (0.7%). Tree willow, shrub willow, dwarf birch and Siberian dwarf pine grow on an area of ​​2,845 ha (1%) (data from PNP, 2002).

The territory of the park, despite the nature protection regime, was subjected to a rather significant impact of natural (abiotic) (forest fires, early snowfalls, floods, etc.) and anthropogenic factors (laying of clearings, roads, logging, construction, plowing, etc. .) factors. As a result, during the period of existence of the PNP (from 1986 to 2002), some transformation of the PNP lands took place.

Thus, as a result of forest management, the area of ​​light-coniferous forests decreased by 10.53%, deciduous - by 1.66%. Due to annual forest fires, the area of ​​burned areas increased by 27.68%. In general, the area of ​​forest land during this period decreased by 6.9%. At the same time, due to the natural process of reforestation and reforestation (planting pine seedlings), the area of ​​felled areas decreased by 10.8%. The area of ​​agricultural land remained practically unchanged, with the exception of hayfields, the area of ​​which decreased by 0.24%. The area of ​​other lands (gardens, estates, roads, sands, etc.) increased by 11.57%. In general, for the period from 1989 to 2002. the land area of ​​the PNP decreased by 5.92% (see Table 17).

A qualitative assessment of the suitability of PNP lands for wolf habitat in them according to four indicators revealed the following:

According to the abundance (population density) of the main food objects, light coniferous, deciduous and marsh classes of lands were assigned to the 2nd class of bonitet (Table 18), which are characterized by the maximum population density of wolf food objects (wapiti from 5.9 to 9 ind./thousand .ha, roe deer - from 10.5 to 18 ind./thousand ha, elk - from 0.8 to 3 ind./thousand ha) in the winter season (Table 27, Fig. 3-5); the 5th class of bonitet included the Siberian stone pine, bald, agricultural (arable land) classes of lands (see Table 18), where the minimum population density of wolf food objects is observed in the winter season (red deer - from 0.8 to 1.6 ind. ./thousand ha, roe deer - from 0.8 to 5.3 ind./thousand ha, elk - from 0.03 to 0.05 ind./thousand ha (Table 27, Fig. 3-5) ; dark coniferous, dwarf birch and agricultural classes of land were assigned the 3rd class of bonitet, since the density of the main forage objects in the winter season is quite high here (Waper deer - from 0.3 to 3.37 ind./thousand ha roe deer - from 7 to 11 ind./thousand ha, elk - from 0.44 to 1.3 ind./thousand ha) (Table 27, Fig. 3-5);

Influence of wolf predation on the age and bottom structure of wild ungulate populations

In the NNP, the wolf is the second factor, after humans, that can significantly affect the number of wild ungulates. However, predators can perform their regulatory functions only under strictly defined ratios of their abundance and the abundance of wild ungulates. According to D. Pimlott (1967) (Pimlott, 1967), the "predator-prey" system will be balanced if the ratio of their numbers is 1:30.

An analysis of the dynamics of the number of wolves and wild ungulates in the PNP showed that the red deer had a normal ratio (1:30) and close to it in 1987 (1:29), and in the period from 1990 to 1994 and in 2002 d. In roe deer, a normal ratio and close to it took place in the period from 1990 to 1994. and in 2002 In elk and wild boar, the normal ratio was never observed, since the number of these species of ungulates in the PNP never exceeded 180 individuals, and in the wild boar in some years it was so small that the ratio was 1.2: 1 (2000), 1, 5: І (1997), 2: 1 (1995), 3: 1 (1996) in favor of the wolf (Table 51).

The musk deer is also a rather small species of ungulates in the park, the maximum number of its number is 345 individuals (1995), so the normal "wolf-prey" ratio in this species of ungulates has never been observed (Table 51).

In the white hare, despite the abundance of this species in the park (the maximum number was recorded in 2000 - 3390 individuals), the normal "wolf-prey" ratio was also not always observed (see Table 51).

Thus, at present, there is no balanced predator-prey system in the PNP with a normal ratio of 1:30, which indicates that the optimal size of the wolf population is exceeded.

In the process of evolution, wolf predation has developed as an effective way of influencing the population dynamics, field and age composition of prey populations, moreover, in a way that humans cannot duplicate (Peterson, 1977).

IZUBR. Of all the recorded deaths of red deer in the PNP for various reasons, including the fault of poachers and diseases, in the period from 1995 to 2002. (n = 359) wolves account for 87.7% of all cases (n = 315). The share of red deer in wolf prey for this period was 43.95% (Table 46), and the average annual death rate of red deer was 4.9 ± 0.43% (Table 52), while annually one red deer crushed by wolves falls on 1, 42,000 hectares of PNP land.

As a result of the analysis of the sex and age structure of the prey, it was found that in red deer, the largest death rate is observed among young females (up to 2 years old) 34.2%, adult samsi (up to 2 years old) are in 2nd place - 28.0 %, on the 3rd young males - 27.6%, least of all - 10.1% die due to the fault of adult male wolves (Table 53). The predominance of females of all ages among the dead red deer, in our opinion, is due to the following reasons:

1. It is easier for predators to get a female, since a male, especially an adult, is physically stronger; getting him is associated with certain difficulties, including the risk of serious injury.

2. Red deer, like most ungulates, is a polygamous species (the ratio of "male to female" in its populations is 1:2 (Yurgenson, 1968)), and therefore females of any age are always more than males, and therefore their share in the prey of the wolf is much larger.

Young animals of both sexes, as the most inexperienced and weak, are the first to fall prey to predators, their share in the prey of the wolf is also much larger (64.6%) than adults (25.7%) (see Table 53). Using departmental materials and our own survey data on cases of death of red deer from wolves, we determined the relative size and territorial features of their death in the territory of the PNR for the period from 1995 to 2002. according to the method of V.M. Glushkov (1979), according to which the territory of the PNP was divided into 3 zones:

1. Northern - this includes Ongurenskoye, Ostrovnoye, Elantsinskoye, Beregovoye forestries.

2. Central - Pribaikalskoye, Listvyanskoye, B. Rechenskoye forestries.

3. Southern - Baikal, Polovinskoye, Marituyskoye forestries.

For A was taken the annual percentage of death of red deer from the wolf at the station (Bolyperechenskoye forestry);

B is the annual percentage of red deer deaths from wolves in the Irkutsk region (according to the Regional Directorate for the Rational Use and Protection of Hunting Resources);

СІ - annual percentage of red deer deaths due to this cause in a certain area of ​​the PNR (Сі - northern group; С2 - central group; С3 - southern group).

The maximum average annual death rate (SD of red deer is observed in the Southern group of forestries - 6.3 ± 0.8%, the minimum in the Northern - 4.31 ± 1.1%. The maximum average annual relative mortality rate (X) was also noted in the Southern group of forestries 4 .41 ± 1.11%, minimum 3.19 ± 0.45% in the Central group (Table 54).

Such a distribution, in our opinion, is due to the fact that the forestries of the Southern group (Marituyskoye and Baikalskoye) are located on the coast of Lake. Baikal, some parts of which are wintering grounds for red deer, whose population density in the period of deep snow reaches 30 ind./1000 ha (data from the NNP). Wolves move there after the ungulates and stay there throughout the winter, and since in the Southern group of forest areas the minimum average annual number of red deer (156.6 ± 24.3 heads) and the maximum wolf (21.44 ± 3.72 individuals ) (Table 55), then its predatory pressure on red deer is much higher here than in other areas of the park.

Improving Accounting Methods

The regulation of the wolf population should be organized according to a specific plan, the main condition of which should be to take into account the number of these predators and their distribution throughout the territory, since for planned work on their extermination, it is necessary to have as accurate data as possible on the number and distribution of animals over the land.

At present, in many works, it is practiced to use the average annual number of skins harvested in a particular area as a quantitative indicator of the population, and to determine, on its basis, the approximate size of the wolf population. This method cannot be rejected completely, but it cannot be recognized as the only and exact one either, since it is based on many conditional assumptions (Kozls, 1952). First, the number of wolves killed in a given area in different years is not always in the same ratio to the total number of wolves living in a given area during that period; secondly, there are many reasons for activating or weakening the prey size of wolves: the presence or lack of wolf hunters, the degree to which they are provided with the necessary means of fighting wolves, climatic conditions, etc.

In the whole country, according to the size of the commercial sample, it is possible to make approximate calculations of the movement of the wolf population, since the increase in the production of this predator over the years will, as a rule, be directly proportional to the increase in their total number in the country, but such an assumption can be valid only as long as while there is a struggle with the wolf, and not the total destruction of this predator, that is, until the annual production exceeds the annual offspring.

In most regions of Russia, wolf counts are still carried out at a rather low level, since in most cases local methods are used that are not suitable for this species, despite the fact that there are specially compiled by Yu.P. Gubar "Methodical instructions ...", which were approved by the Glavohota in 1986.

The similarity of the sample (sample) and the arena of extrapolation (general population) is expressed in the population density of the species (or relative indicators, for example, Pu - an indicator of accounting or the number of traces encountered per 10 km of the route), therefore, it can be achieved only in three cases (Smirnov, 1973 ):

1. When the animals are distributed relatively evenly over the territory.

2. When there are many samples and they are distributed fairly evenly over the area under study.

3. When the samples cover areas of the territory with different population density of the species in the same proportion of areas that exists in the arena of extrapolation.

In principle, it is impossible to achieve compliance with the first condition, especially in the case of a wolf, since in nature animals, as a rule, are randomly distributed over the territory, and their population density varies significantly in different parts of the study area.

It is very difficult and inexpedient to place samples (recording sites and routes) strictly uniformly over the study area, since the record will have to be carried out in places that are obviously uninhabited by this species, which will entail the need for transitions, moving, and examination in hard-to-reach places (Kuzyakin, 1979), this is the first the turn refers to the wolf - an animal moving around the hunting area along strictly defined routes.

An analysis of the state of affairs with conducting wolf counts in the PNP revealed the need to revise the methods currently used for this, and adopt those that take into account the characteristics of the ecology of this predator, and, therefore, give more reliable results.

In our opinion, the method proposed by V.V. Kozlov (1952), based on the registration of animals according to the traces of vital activity in the winter period. The first and indispensable condition for the successful conduct of such accounting is the detailed knowledge by the accountants of the characteristic features of the trace of a given animal species, which makes it possible to accurately determine the species of the trace, as well as the sex and age of the animals.

When choosing the optimal time for counting the wolf in the PNR, we took into account, first of all, the behavior of this predator during the annual cycle, as well as the material possibilities of organizing such a record in the park.

We carried out a wolf count using this method on the territory of the Bolsherechensky forestry, before it began on the territory of accounting work (September-October), 35 people were interviewed using a special questionnaire (Appendix 5) (local population, hunters, foresters, park employees). The data obtained a month before the start of the count on the encounters of wolf tracks and the places of attacks of this predator on wild and domestic animals were entered on a schematic map of the research area, in parallel, information was collected about where the howling of wolves was heard in summer (that is, where the den was approximately ).

All census takers were provided with a large-scale map of the area, with conventional signs marked with places of traces encountered, permanent crossings, remains of prey, places of former dens of wolves, etc. - beginning of November.

Establishment of a survey site with an area of ​​35 thousand hectares (350 km) - 15x23 km, which corresponds approximately to the size of the hunting and fodder area of ​​a wolf family, and the placement of survey routes were planned so that they include, if possible, all classes of land available in the PNP in order to facilitate further extrapolation to the entire territory of the PNP. Recording routes in the amount of 6 pieces (with a total length of 133 km) were first outlined on a map-scheme, in such a way that the place of the lair was located approximately in the middle of this registration area, in the absence of information about the location of the wolf's lair in this tract, the routes were planned based on the available messages about encounters of fresh tracks of wolves or about places of attacks of wolves on domestic or wild animals in winter and summer-autumn periods, so as to cross as many areas as possible in which wolf crossings were noted. Five routes 15 km long were laid parallel to each other, and the sixth was laid in the middle of the accounting area perpendicular to the direction of the other routes; its length was 23 km (Fig. 21).

By studying wolves living in Yellowstone National Park, a team of researchers has developed a new model for understanding how the ecological and evolutionary traits of animal populations change with the environment. Researchers have been recording data from the National Park for more than 15 years, including information on the body size and coat color of wolves, as well as a highly fluctuating population, which, at the latest data, stopped at around 97 individuals.

“The findings that we have been able to draw indicate that biologists should stop evaluating the size of a population in isolation from its properties. Changes in the environment invariably make adjustments to the ecology and evolution of species,” explains Tim Coulson, a researcher at King's College London.

Wolves from Yellowstone National Park

An international team of wolf specialists, geneticists and statisticians began collecting data in the National Park when wolves, absent for 70 years, reappeared in the reserve in 1995 and 1996. Within seven years, the newly appeared population of 40 individuals increased in number to 180 wolves. The population changed until in 2008 there was a sharp decline in numbers. The researchers combined the data with genetic information and other characteristic properties of wolves.

According to Coulson, biologists and those who study animal populations in the wild have noticed over the past decade of research that by changing the environment in which a species lives, this means climate change, the introduction of new species, disease epidemics, and so on. - it is possible not only to change the population, the number of individuals living in it, but also the characteristic properties of animals. He noted that this is a fairly common phenomenon, but it was not possible to understand how and why it occurs.

The researchers used the statistics to determine how "good" or "bad" the years were in terms of wolves' survival, growth, and birth rate. These factors were influenced by environmental changes, including food availability, competition, disease, and weather. They used these survival rates to understand how these environmental conditions affected various characteristic traits of wolves. The researchers noted that they were able to learn some significant details, for example, that the population did experience more negative phenomena when bad years followed one another than when bad years were followed by good ones.

“Yes, one bad year has a short-term impact, but in the long run it's much worse for the population if there's a long series of harsh conditions,” says Coulson. “We don’t have the data to figure out exactly what makes a year good or bad.” According to the scientist, what undoubtedly plays a role is the presence of food and disease.

The researchers also noted that these changes may have different and sometimes conflicting effects on the life cycle of wolves or other animals studied. Survival, reproduction, and individual development are the three key characteristics of a population, and they can all respond to environmental changes in very different ways. Depending on this reaction, an impact on the population will be created.

Predicting future changes

The same model for how wolves respond to environmental change can be used for other animals and even for insects and plants. Environmental changes don't just affect ecology or population evolution, they affect both at the same time. Both ecological and evolutionary changes can occur rapidly in a population that undergoes ecological change.

For example, researchers can model the behavior of rodents and other pests to determine how they will respond to the replacement of urban green space by parking lots. One cannot simply assume that changes in the environment will lead to a decrease in the population, it can also increase. The answer to some kind of ecological change may be an excess of a certain type of rodent.

Clear evidence of the fragility of the ecosystem and convincing proof of the long-known truth that any intervention in the life of nature can turn into the most unexpected surprises.

“On a windy August afternoon, University of Oregon botany professor William Ripple gazes in fascination at a four-meter poplar growing in the Lamar Valley of Yellowstone National Park. “See those kidney scars? - asks the scientist, bending a thin trunk to the ground and showing me the marks that indicate the rapid growth of the tree. “Moose haven’t nibbled on it this year or last year—they haven’t touched the tree since 1998!” And if wolves had not appeared in Yellowstone Park, the poplars would have disappeared completely. Here is clear evidence of the fragility of the ecosystem and convincing proof of the long-known truth that any intervention in the life of nature can turn into the most unexpected surprises.

In 1995, by decision of the US National Park Service and the Fish and Wildlife Service, three dozen wolves were reintroduced into Yellowstone National Park. Since then, predators have halved the population of Yellowstone elk, which has led to the resumption of growth of many plants. With the appearance of young trees, beavers returned to the park. The dams they build cause rivers to flood, which also speeds up the restoration of vegetation. The return of wolves also affected the lives of other inhabitants of the park - coyotes, grizzlies, red foxes, ravens and even small birds.

In the dead of winter 1995, 31 wolves (Canis lupus) were brought from Canada to Yellowstone by the US National Park Service and the US Fish and Wildlife Service. These were the first wolves to appear since the beginning of the 20th century. all gray predators here were exterminated by hunters. Environmentalists hoped that the reintroduction of wolves would help restore Yellowstone's former biodiversity. For example, it has been suggested that predators will "cull" part of the large Yellowstone moose population. With the extermination of wolves, their numbers in the park increased rapidly. The brought predators fully justified the hopes of scientists. Today, 16 wolf packs "patrol" the park, each consisting of 10 animals and killing one elk daily. As a result, the number of moose, which reached by the beginning of the 1990s. 20,000 individuals, today is less than 10,000 animals.

Ripple wants more trees in the park. “I love poplars,” the professor remarks dreamily as he sits over a cup of coffee in a cozy restaurant near Yellowstone Park, where he conducts field research. When word reached a scientist in 1997 that Yellowstone was getting thinner and no one knew why, Ripple went to the park determined to solve the mystery.

The professor examined wood samples from 98 poplars and found that only two of them sprouted in the late 1920s. - it was at this time that the last population of wolves was destroyed in the park. It is curious that both trees grew in a place where moose did not dare to visit for fear of gray predators. In addition, Ripple noticed that either very large or very tiny poplars grow in Yellowstone - medium-sized trees were completely absent, because. between the 1930s and 1990s. moose did not give the opportunity to germinate new shoots. So the scientist discovered the first clear evidence of the "ecological effect of wolves."

According to this theory, gray predators maintain such a number of moose in the park that they are simply not able to destroy the new growth of poplars and willows. When the wolves in Yellowstone were exterminated, the number of elk quickly increased and they began to literally devastate the Lamar River valley, gradually displacing many species of animals from it. For example, with the disappearance of young trees, beavers lost their main food, they were last seen in the Lamar Valley in the 1950s. And when the rodents stopped building dams and the artificial reservoirs they created dried up, there were fewer succulent plants in the valley - the main food of grizzly bears.

Wolves brought to Yellowstone Park in 1995 began to multiply rapidly. Scientists soon noted not only a decrease in the number of moose, but also some changes in their behavior. Huge powerful ungulates began to spend less time in the rivers, and on land they began to stick to places where it was easy to notice the approach of gray predators. If the wolf effect hypothesis is correct, young trees should turn green for the first time in seven decades in Yellowstone Park.

And they really started to return to the park. Most of them grew where the moose did not have a full 360-degree view of the area during feeding. Young three-meter willows, for example, have risen at the foot of a low hill, which should block part of the area with elk. When looking at these trees, it immediately becomes clear that the teeth of moose have not touched their branches for several years. “The animals don't feel safe here,” Ripple says. “From here they can’t see what’s happening behind the hill, and therefore they are afraid to stay in this place for a long time.” But some 50 m from the hill, where the plain stretches and a vast panorama opens before your eyes, the willows barely reach a height of 1 m and in three years have clearly been plucked more than once by elk. “That's what I call the ecology of fear,” says the professor.
Revegetation in the Lamar Valley is accompanied by other environmental changes. A little further upstream, a beaver dam has grown - one of the first erected by rodents on this river in the last 50 years. On the Slough Creek (one of the tributaries of the Lamar River), beavers have already built six such structures. According to Ripple, the animals returned to the park because now they can feed themselves here. Other changes are coming. Growing trees will strengthen the banks and stop soil erosion. Under the shade of dense greenery, the river will become more shady and cool. More plant debris will get into the water, the accumulation of which will slow down the flow of the reservoir and make it a more suitable habitat for trout and other large fish.

The influence of wolves does not appear to be limited to the plant components of the Yellowstone Park food chain. Their appearance, for example, greatly affected the local coyotes. Three years before the introduction of predators, the study of the coyote population was carried out by the leading employee of the Yellowstone Environmental Research Center, Robert Crabtree. After the arrival of wolves, the number of coyotes in the park decreased by 50%, and in the territory of wolf packs - by 90%. Male coyotes have noticeably decreased in size during this time. Crabtree explains this by saying that they were more aggressive towards the wolves, threatening them, but in the end they were defeated. The decline in the number of coyotes has led to a sharp increase in the number of their prey - voles, mice and other rodents. This, in turn, caused an increase in the number of red foxes and birds of prey. And since both of them feed on small birds, their numbers in the park could also change.

The return of wolves also affected the lives of other large carnivorous inhabitants of the park. Grizzly bears and cougars rarely attack adult moose. Wolves, on the other hand, prefer to attack them. Having eaten their fill, they usually go to bed, leaving the remains of their prey at the complete disposal of all kinds of carrion animals - from grizzlies to forty. It was in Yellowstone that a record number of ravens (153 birds!), Feeding on the carcass of a dead elk, was recorded. “Each time the remnants of the wolf meal are eaten up by other animals. We have seen bald eagles, coyotes, crows and magpies feeding on them,” says Douglas Smith, head of the wolf reintroduction project. “I would like to know what these animals ate when there were no wolves in the park.”

But have gray predators really become the "driving force" of all changes? Most scientists answer the question in the affirmative. According to Smith, wolves are to Yellowstone what water is to a swampy park; the main factor responsible for the formation of the ecosystem. Biologists observed similar changes in the Canadian Banff National Park, when in it in the 1980s. wolves returned: a few years after their appearance, willows again grew here and the species diversity and number of songbirds doubled. Today, scientists come to Yellowstone specifically to study the first evidence of the powerful influence of gray predators on the ecosystem of river banks.

The scientific discussion about the impact of wolves on the ecosystem of Yellowstone Park with renewed vigor has stirred up the question of the most adequate ways to regulate the number of local moose. There was a time when the National Park Service thought that there were too many moose in Yellowstone: in the 1960s. groups of foresters were repeatedly sent there to catch and shoot animals. By the end of the decade, the total number of moose was reduced to 4,000 individuals. Under public pressure, their destruction stopped, and in the 1970s. The National Park Service began to implement a policy of "natural regulation" of the number of animals in state reserves, deciding to turn them into "islands of virgin America." Since then, the number of moose in Yellowstone began to grow.

Today, decades later, Montana and other opponents of this approach accuse the National Park Service of causing huge herds of elk to cause irreparable damage to vast areas of natural pastures. In their opinion, the very idea that nature could develop naturally in an unnatural situation was insane.
Other researchers argue that all the assurances of the Park Service that the number of Yellowstone elk is within natural limits, refutes the very fact of the renewal of vegetation along the banks of the river. Lamar. Smith offers to look at the situation from a different angle. “Over time,” the scientist says, “the number of elk will undergo significant fluctuations. Today there are really too many of them, but if we consider the dynamics of the population over a long period, its size does not go beyond the natural boundaries.

Whatever conclusions scientists may come to regarding the “ecological effects of wolves”, everything that happens in Yellowstone Park clearly indicates that representatives of the canine family unwittingly act as skilled restorers of the natural environment. By hunting moose, they cause huge changes in the park's ecosystem. From a human point of view, many of these changes are very useful - in any case, if people decided to implement them, the work would cost the state a huge amount of money.

The Yellowstone Wolves also taught other useful lessons. They clearly showed the important role of predators occupying the highest levels of food chains in maintaining the ecological balance and what natural resources the part of the country where these predators were exterminated lost. Truly, the wolf has become today a symbol of all the unforeseen and unknown consequences caused by the ill-conceived intervention of man in the life of nature.

In the world of science. 2004. No. 9.

Further, in the same place it was shown that “thanks to wolves, local grizzly bears get more edible berries, such as, for example, fruits of the alder-leaved shadberry (Amelanchier alnifolia). William J. Ripple et al. (2014) compared the percentage of berries in bear feces collected in 2007-2009 (778 samples) with data from a similar study conducted 19 years earlier. Bears have been found to eat more berries these days. In July, the remains of berries were contained in 5.9% of the samples (in the past - in 0.3%), and in August - in 14.6% (in the past - 7.8%).

The researchers speculated that a factor that caused this change was the return of wolves to Yellowstone Park. Bears and moose compete for berries, and bears lose in this fight, elk eat most of the fruit. When wolves were reintroduced into the national park, they reduced the population of elk, so there was a redistribution of the resource in favor of bears.

The complete eradication of wolves from most of North America in the 1920s led to an uncontrolled growth of the moose population. Wolves reappeared in Yellowstone in 1995. Their numbers are also recovering in other forests of North America, which leads to the return of the number of coyotes, elk and deer to the previous level.”