Fokin S.Yu. Acoustic signaling and biological basis for controlling bird behavior during artificial game breeding // Game breeding in hunting. Collection of scientific works of the Central Scientific Research Laboratory of Glavokhoty of the RSFSR. Moscow, 1982. pp. 157-170.
ACOUSTIC SIGNALING AND BIOLOGICAL BASIS OF BIRD BEHAVIOR CONTROL IN ARTIFICIAL WILDLIFE BREEDING
The possibility of using bioacoustics in hunting was first pointed out by V.D. Ilyichev (1975) and A.V. Tikhonov (1977). However, special research was started only recently, at the Central Research Laboratory of Glavohota of the RSFSR. They will help solve a number of complex problems facing domestic game breeding and increase its efficiency. Until now, in the hunting industry, sound communication between animals has been used only when hunting game using the luring method and when counting some animals by voice. However, the study of bird sound signaling has shown the fundamental possibility of using it in controlling the behavior of birds.
The development of methods for controlling the behavior of birds is based on knowledge of individual behavioral acts and vocal reactions of birds in the behavioral complex characteristic of a given species. The basis of bird communication is acoustic and visual communication, which have a close relationship. The complexity of organizing acoustic signaling systems in birds is manifested in the presence of two basic principles for encoding information in signals. On the one hand, this is multifunctionality (Simkin, 1977), in which the same acoustic signal has several functions (for example, the song of birds serves to mark the nesting territory, “scare off” other males, but at the same time to attract females and even to divert the enemy from the nest). On the other hand, this is parallel coding, according to which different types of signals convey similar information (Simkin, 1974), for example, various comfort signals of chicks reflect the same comfort situation. The dominance of the emotional principle over the semantic principle in many cases makes it difficult to analyze the acoustic signaling systems of birds. However, in most brood birds, acoustic signals are more often associated with a certain functional significance, especially during the nesting period and during the movement of broods (Tikhonov and Fokin, 1931). The specific organization of sounds (tonal, noise and trill signals) is associated with the most rational range of their propagation (Ilyichev, 1968; Simkin, 1974).
Attempts to classify bird calls have been repeatedly made by various researchers. The main difficulty is that it is impossible to identify the mechanism of language in birds and humans, since the logical foundations of the communicative processes of animals are fundamentally different (Simkin, 1932). A.S. Malchevsky (1972) divides the sound signals of birds into 2 main types: situational and signaling. In the first case, communication occurs with the help of signals that have an expanded meaning depending on the biological situation. In the second, a system of specialized sound reactions is used, and the signals associated with a certain physiological state of the bird have a strictly defined biological meaning. This type can be classified according to functional characteristics. The author identifies calling and protective signals with a detailed classification of each group (Malchevsky, 1974).
G.N. Simkin (1977) proposed a new scheme for the functional classification of acoustic signals of birds, based on the maximum differentiation of signal values. He divided all sound signals into 3 main groups, each of which includes smaller categories:
1. The main urges given throughout the year: the main species calling cry, school and group urges, food signals, alarm signals, conflict signals, special signals of the emotional sphere.
2. Urges of the reproductive cycle: mating phase, parental phase.
3. Calls of chicks and fledglings.
Parental signals of brood birds are usually divided into “following call”, “food call”, “gathering signal”, contact signals, alarm signal (in chicken birds the signals for an airborne and ground enemy are different).
We proposed dividing the acoustic signals of chicks into 3 categories (Tikhonov and Fokin, 1980).
1. Signals of a negative physiological and social state, including signals of “discomfort,” indicative and nutritional.
2. Signals of a positive physiological and social state, dividing them into signals of “comfort”, warming, saturation, group contacts, following, pre-sleep
condition.
3. Alarming and defensive signals (anxiety, distress, fear).
Such a fractional classification forms the basis for solving many problems of controlling the behavior of birds in game breeding. Knowing the basic functional meaning of a signal characterized by certain physical parameters, one can pose the inverse problem, studying the influence of this signal on the behavior of birds.
The bird makes its first sound signals while still in the egg, 1-2 days before the shell hatches. In the auditory analyzer of chicks, first of all, those nerve cells that are “tuned” to the species-specific frequency of the female’s voice mature (Anokhin, 1969). Sound communication between the female and the chicks is established already at the end of incubation (Tikhonov, 1977). Indirect learning in brood birds, including signal succession and group learning (Manteuffel, 1980), plays an important role in the ethological preparation of young birds for independent life. Of particular importance is the acoustic behavior of parents as a factor in stimulating and polishing the behavior and communication of young birds in the brood (Simkin, 1972).
In artificial game breeding, humans deprive the chicks of contact with the female. Incubation of eggs, enclosure and cage rearing of young animals without brood hens leads not only to the impossibility of developing adaptive behavioral reactions that are formed in nature on the basis of individual and group experience, but also to the extinction of some important innate behavioral acts, in particular anxiety reactions. Our experiments on mallard ducklings showed that the innate reaction of flight in chicks to alarming signals from the female is most clearly manifested on days 2-3 and, without visual reinforcement, fades away already on the fifth day. Fixed by special “scare sessions” (loud screams, shots, sirens, special scaring by people), the alarming reaction persists until release into the wild. Subsequently, it becomes an integral component of the behavior of released birds.
However, the use of special “scares” is not the main factor in the formation of a “wild” behavioral stereotype in birds raised in captivity. As is known, birds raised in constant contact with humans differ sharply in behavior from their wild relatives. Such birds do not have directed alarm-defensive reactions to predators, which makes them easy prey for both ground and air enemies. Hunting for birds that are not afraid of humans loses its sporting interest and even becomes inhumane.
The main factor in birds becoming accustomed to humans is the effect of imprinting (imprinting) the appearance and voice of a person on the chicks during the “sensitive” period, limited to the first 2-3 days of life. In the future, the positive reaction to humans is further enhanced due to the formation of conditioned reflex reactions in the process of feeding and constant communication with birds. Imprinting is an extremely persistent and practically irreversible process. Therefore, in our opinion, when artificially breeding game, it is necessary to prevent human imprinting on chicks in the “sensitive” period. We conducted a series of experiments consisting of isolating small ducklings from humans at different periods. The experimental cages with houses were curtained on all sides with dense material, and the top remained open. During feeding and changing water, the chicks saw only the hands of the person serving them, and in the process of giving food they always ran into the house. Ducklings isolated from humans for a “sensitive” period subsequently got used to them, but on the basis of conditioned reflex reactions. Special methods of “scare” after releasing them into the grounds (shots from guns, etc.) contributed to the disruption of these positive conditioned reactions: the ducks began to be afraid of people. And yet, their flight reaction in response to the appearance of a person was more sluggish than that of their wild relatives. At the same time, ducklings raised in the usual way reacted indifferently to the appearance of people.
The best option turned out to be keeping the ducklings in isolation from humans for the entire time, right up to their release onto the land, i.e. up to 25-30 days. Such ducks were practically no different in behavior from wild ones: they flew away when a person approached, they were afraid of unfamiliar objects, air and ground enemies, and even “peaceful” birds. Hunting such game was practically no different from hunting wild birds.
Currently, our main task is to search for the technical implementation of this method of raising young game birds, taking into account the specific design of game farms. Obviously, you need to start with strict adherence to the following requirements. During the hatching period, complete silence must be maintained in the incubator to avoid the chicks imprinting human voices. For the first 5-7 days, the hatched chicks are transferred to brooder cages, closed on all sides with dense material, which should be folded back at the door when feeding and changing water. Then the young animals are transferred to enclosures with walls covered with plywood or roofing felt and raised for up to 25-30 days. During the growing process, it is very effective to carry out 4-5 “scares” after releasing the young animals onto the land. On the second day after release (but not on the day of release), several people come to the place where the released game is kept and fire several blank shots, achieving a flight reaction in the birds. Birds that have been isolated from people for a “sensitive” period, unlike those raised in constant contact with humans, are afraid of gunshots. The combination of a shot and the appearance of a hunter produces a negative reaction in birds towards humans. Already 3-4 days after regular scares, the mere appearance of a person, for example, near a pond, causes the flight of young ducks, who try to hide in the thickets.
Ducks released at a later age are more difficult to run wild, and if in the first days of life the chicks were not isolated from people, then such birds, as a rule, practically do not react to shots. Wilding goes faster if the birds have seen the death of their fellow bird several times after the shot (Ilyichev, Vilke, 1978). You can teach birds to avoid people using the principle of combined repellents - that is, use not only the direct cries of people, gunshots, but also recordings of various sounds - cries of distress, alarms, a sharp takeoff of a flock of birds, high-intensity sounds (up to 120 dB), ultrasounds (up to 40 dB). kHz) (Tikhonov, 1977). However, our hunting farms are not yet equipped with special equipment for using these methods and it is not worth dwelling on them yet.
In the practice of game breeding, there is a need to collect chicks in a certain place. During the sudden onset of bad weather, small chicks hide in open enclosures at night and may die from hypothermia. The maintenance personnel of game nurseries are forced to drive them into shelters. Sometimes it becomes necessary to transfer young animals from one room to another, collect them in a certain place for weighing, dividing into groups, etc. Such work can be facilitated by using acoustic attractants - sound attractants. The following reaction of a single chick has been studied quite fully, but in game breeding we are dealing with large groups of chicks, and practically no experiments have been carried out to study the following reaction of a group of chicks.
Chicks of brood birds are characterized by an approach reaction in response to the calling signals of the female or her imitators - monotonous signals (Malchevsky, 1974). Single chicks were offered recordings of sound signals of varying functional significance. They responded with an approach reaction to juvenile comfort signals and female calling signals. The use of these two signals and their monofrequency imitators as attractants for a group of chicks was initially unsuccessful. In our opinion, the lack of reaction in a group of chicks approaching the sound source is due to two reasons. Firstly, the level of motivation of the chicks plays a decisive role in stimulating this reaction. A chick, isolated from its brethren, experiences constant discomfort, which prompts it to react closer to certain sound signals. And in our experiments, the chicks were in comfortable conditions - they were close to their brothers. In nature, comfortable conditions for chicks are created by the female, and in artificial conditions - by humans. The chicks only imprint on each other and people; the need for constant contact with the female disappears. Naturally, in artificially created comfortable conditions, the chicks will not have an approach reaction, since sound signals alone are not enough, and they do not have the corresponding internal factors (state of discomfort). Second, as shown by Gottlieb (1977), an acoustic-visual stimulus evokes a more powerful pursuit response than an acoustic stimulus alone. In nature, birds following their mother are guided by both her appearance and her voice. In artificial conditions, the chicks “do not know” the female, and the object of their imprinting may be the first moving sounding object seen in life.
It follows that the motor reactions of chicks can be controlled in two ways: either by using acoustic attractants in uncomfortable situations (cooling, hunger), or by using acoustic-visual attractants (moving sounding speakers), having previously ensured that the chicks imprint them. Our experiments fully confirmed this (Fokin, 1981). For example, small ducklings that did not respond to the reproduction of the duck’s calling quacks quickly gathered near the speaker after turning off the lighting and heating in the brooder; The baby pheasants actively followed a moving speaker through which recordings of their comfort calls were played.
With an increased density of chicks, an increase in their aggressiveness is observed, manifested in collisions at feeders and drinkers, pecking, and restlessness. This has a depressing effect on their growth and development. Industrial noise also has a negative impact on the life activity of birds (Rogozhina, 1971). Phelps (1970) found that music had a calming effect on the behavior of laying hens, with an even greater effect when the hens were played recordings of their comfort calls. As experiments on chickens (Ilyichev, Tikhonov, 1979) and quails (Fokin, 1981) showed, the use of monofrequency signals of the appropriate frequency led not only to “calming” the chicks, but also significantly increased their feeding activity. Feed consumption increased and daily weight gain increased sharply. Thus, the weight of experimental quail reached an average of 147.7 g by the age of two months, while control chicks of the same age reached only 119.6 g.
We also used comfort signals from chicks and females as stimulants. A good effect is achieved by periodically playing food sounds of non-vocal origin that accompany feeding (the beak striking the substrate, the alkalization of water, etc.).
Currently, intensive research is being conducted to develop optimal modes for stimulating young animals with sound signals. It is known that in spring current sounds stimulate the growth of the gonads of birds (Promptov, 1956). In addition, most species are characterized by the phenomenon of sound induction, the essence of which is that the specific mating song stimulates similar sound responses in males of the same species of birds (Malchevsky, 1982); Brockway (Brockway, 1965) notes that the vocalization of mating birds stimulates the oviposition process with signals.
Our experiments on stimulating mallard ducks, wood grouse, black grouse and chukars kept in the game nursery of the Central Scientific Research Laboratory with current sounds showed the large role of sound induction in the mating behavior of birds. In grouse and chukars, artificial sound induction disrupted the species-specific circadian rhythm of displaying, “forcing” them to display during the day, even in inclement weather. Playing recordings of the mating call of a male Japanese quail in a sparrowhawk led to an increase in the sound activity of all males: the number of mating calls emitted per hour by all males in the sparrowhawk increased by 1.8 - 2.0 times, and the number of matings also increased. Obviously, sound stimulation promotes increasing the egg production of birds. In any case, in our experiments, the total number of eggs laid in the first days of voicing increased by 36–47%. Then there was a drop in egg production, which can obviously be explained by the effect of birds becoming accustomed to constant external stimuli.
These areas do not limit the range of exploratory studies of the practical use of bioacoustics in game breeding. The distinctive features of the voices of domestic subspecies of the common pheasant are studied, the role of sound reactions in the formation of pairs in geese and geese, which are characterized during the breeding season by the so-called antiphonal duets, also characteristic of some cranes, owls and passerine birds, is clarified (Malchevsky, 1981). Methods of catching wild birds in nature using “acoustic traps” are being explored.
Express methods for determining sex by voice in day-old young game birds are being developed, and research is underway on acoustic stimulation and synchronization of hatching of chicks.
Literature
Anokhin P.K. Biology and neurophysiology of the conditioned reflex. - M.: Nauka, 1968.
Ilyichev V.D. Physical and functional characteristics of birds' voices. - Ornithology, 1968, issue. 9.
Ilyichev V.D. and others. Bioacoustics. - M.: Higher School, 1975.
Ilyichev V.D., Vilke E.K. Spatial orientation of birds. - M.: Nauka, 1978.
Ilyichev V.D., Tikhonov A.V. Biological basis for controlling bird behavior. I. Chicken. - Zool. zhurn., 1979, vol. VIII, - issue. 7.
Malchevsky A.S. On the types of sound communication of terrestrial vertebrates using the example of birds. - In: Animal Behavior. Mat. I All meeting on ecological and evolutionary aspects of animal behavior. M., Nauka, 1972.
Malchevsky A.S. Sound communication of birds and the experience of classifying the sounds they make. - Mat. VXAll. ornithol. conf., 1974, part I, M.
Malchevsky A.S. Ornithological excursions. - L.: Leningrad State University Publishing House, 1981.
Manteuffel B.P. Ecology of animal behavior. - M.: Nauka, 1980.
Promptov A.N., Essays on the problem of biological adaptation of the behavior of passerine birds, - M.-L.: Publishing House of the USSR Academy of Sciences, 1956.
Rogozhina V.I. The influence of a sound stimulus on the dynamics of nitrogen compounds and pyruvic acid in the blood and brain of chickens. - Mat. All meeting and conf. VNITIP USSR Ministry of Agriculture, 1971, issue. 4.
Simkin G.N. Acoustic relationships in birds. - Ornithology, 1972, issue. 10.
Simkin G.N. Acoustic alarm systems in birds. - Mat. VI Vses, ornithol. conf., 1974, part I, M.
Simkin G.N. Acoustic alarm systems in birds. -In: Adaptive features and evolution of birds. M., Nauka, 1977.
Simkin G.N. Experience in developing a functional classification of acoustic signals in birds. - Mat. II All. conf. on animal behavior. M., 1977.
Simkin G.N. Current problems in studying the sound communication of birds. - Ornithology, 1962, issue. 17.
Tikhonov A.V. Acoustic signaling and behavior of brood birds in early ontogenesis. - Author's abstract. Ph.D. dis. M., 1977.
Tikhonov A.V. Sound communication between embryos and the brooding female in broodbirds. - Abstract of the report. VII All. ornithol. conf. Kyiv, 1977.
Tikhonov A.V., Fokin S.Yu. Acoustic signaling and behavior of waders in early ontogenesis. II. Signaling and behavior of chicks. - Biol. Sciences, I960, No. 10.
Tikhonov A.V., Fokin S.Yu. Acoustic signaling and behavior of waders during the nesting period. - Bull. MOIP, dept. Biol., 1981, No. 2.
Fokin S.Yu. The influence of acoustic stimulation on the feeding and aggressive behavior of young Japanese quail. - Tez. report XXIV Vses., conf. young scientists and graduate students in poultry farming. 1981.
Fokin S.Yu. Attractant reaction of chicks of brood birds and the possibility of its use in game breeding and poultry farming. - In: Ecology and conservation of birds. Abstract. report VIII All.ornithol. conf., 1981, Chisinau.
Brockway V. Stimulation of ovarian development and egg laying by male courtship vocalization in budgerigars (Melopsittacus undulatus). - Animal Behavior, 1965.
Gottlieb G. Neglected developmental variables in the study of species identification in birds. - Psychol. Bull,. 1973, 79, no. 6.
Phelps A. Piped music: good management or gemmick? -J. Poultry international, 1970, v. 9, №12.
Ecology lesson in 5th grade on the topic "Sound signals in animals and their role in animal behavior"
Goals:
Educational: development of cognitive interest and respect for nature, observation, sustained attention, creative activity, independence, ability to compare, draw conclusions
Educational: formation of concepts about sound signals in animals, the ability to distinguish between them.
Educational: show the connection between animals with the help of sound signals, instill a caring attitude towards nature, the development of a love of beauty, a sense of harmony and beauty.
Equipment: computer, multimedia installation, presentation, pictures of animals, textbook, workbook.
During the classes
1. Organizational moment.
Hello guys! I'm very glad to see you. Look at each other, smile. I wish you a good mood throughout the lesson.
2. Test of knowledge.
Frontal conversation. (The conversation is conducted on the textbook questions at the end of paragraph 46)
Written survey (Complete task 138 in workbooks)
3. Studying new material.
Students report on sound signals in animals.
Teacher's story.
The connection between man and the animal world has always been complex and included two extremes - hunting for animals and love for them. All this led to the fact that man began to train animals and even teach them oral speech. In the course of the joint evolutionary development of humans and animals, talking animals appeared, despite large anatomical differences. It seems that as our knowledge of animal behavior increases, the differences between humans and animals begin to shrink. However, some abilities that humans possess are very difficult to detect in animals. One of these abilities is language.
It seems to us that the presence of language is a unique property of a person.
Animals have their own “language”, their own system of signals, with the help of which they communicate with relatives in natural habitats. It seemed that it was quite complex, consisting of different methods of communication - sounds, smells, body movements and postures, gestures, etc.
Animal language
Sound language is important for animals. People have long believed that every species of animal that exists on Earth has its own language. Using it, birds chatter restlessly or fly away when they hear a signal of danger and alarm.
Animals have their own “language” that expresses their state. The roar of a lion can be heard throughout the entire area - with this the king of beasts loudly declares his presence.
What are the natural sounds made by animals? These are signals expressing their state, desires, feelings - rage, anxiety, love. But this is not a language in our understanding and, of course, not speech. The famous zooethologist K. Lorenz notes: “...animals do not have language in the true sense of the word. The cries and sounds they make represent an innate signal code.” The ornithologist O. Heinroth points to this.
A person’s language is expressed through his spoken language and is determined by the richness of his vocabulary - for some people it is large and bright, for others it is simple. Something similar can be observed among birds and mammals: many of them have varied, polyphonic sounds, while others have rare and inexpressive sounds. By the way, there are completely mute birds - vultures; they never make a single sound. Signals and sounds in animals are one of the ways of communication between them. But they have different ways of transmitting information to each other. In addition to sounds, there is a peculiar “language” of gestures and postures, as well as a facial “language”. Everyone knows that the grin of an animal’s muzzle or the expressiveness of an animal’s eyes vary greatly depending on its mood - calm, aggressive or playful. At the same time, the tail of animals is a kind of expressive of their emotional state. The “language” of smells is widespread in the animal world; a lot of amazing things can be told about it. Animals of the cat, mustelid, canine and other families “mark” with their secretions the boundaries of the territory where they live. By smell, animals determine the readiness of individuals for mating, and also track prey, avoid enemies or dangerous places - traps, snares and snares. There are other channels of communication between animals and the environment, for example, electromagnetic location in the Nile elephant fish, ultrasonic echolocation in bats, high-frequency sound whistles in dolphins, infrasound signaling in elephants and whales, etc.
Research has amended the popular saying: “Mute as a fish.” It turned out that fish make many different sounds, using them to communicate in a school. If you listen to the sounds of fish using special sensitive instruments, you can clearly distinguish them by their “voices”. As American scientists have established, fish cough, sneeze and wheeze if the water does not meet the conditions in which they should be. The sounds produced by fish are sometimes similar to rumbling, squeaking, barking, croaking, and even grunting, and in the cinglossus fish they generally resemble the bass of an organ, the croaking of large toads, the ringing of bells and the sounds of a huge harp. But, unfortunately, in the entire history of mankind there has not been a single case of a fish speaking in a human voice.
Sound signaling exists in all types of animals. For example, chickens make 13 different sounds, tits - 90, rooks - 120, hoodies - up to 300, dolphins - 32, monkeys - more than 40, horses - about 100. Most zooethologists are convinced that they convey only the general emotional and mental state of animals . Some scientists think differently: in their opinion, different types of animals have their own language of communication. Thanks to him, detailed information about everything that happens to them is transmitted. I will give examples of the languages of some animals. Giraffes have long been considered mute animals. However, studies have shown that they communicate with each other using sounds that differ in frequency, duration and amplitude in the infrasound frequency range.
Monkey tongue
Many people like to watch the behavior of monkeys at the zoo (Fig. 3). And how much shouting, noise, energetic and expressive gestures there are in these “warm companies”! With their help, monkeys exchange information and communicate. Even a monkey dictionary was compiled; the first such dictionary-phrase book was compiled by a scientist in 1844 in Paris. It listed 11 signal words used by monkeys. For example, “keh” means “I’m better,” “okoko, okoko” means great fear, “gho” means greeting. It should be said that the famous scientist R. Garner devoted almost his entire life to studying the language of monkeys and came to the conclusion: monkeys truly speak their native language, which differs from humans only in the degree of complexity and development, but not in essence. Garner learned the language of monkeys so much that he could even communicate freely with them.
Dolphin tongue
Dolphins are of great interest to scientists for their good learning ability and the varied activities they exhibit when in contact with humans. Dolphins easily imitate various sounds and imitate human words. In the work of the famous dolphin researcher John Lily, an incident occurred when during an experiment one device broke down, but the tape recorder continued to work and recorded all subsequent sounds. At first, the dolphin could be heard reproducing the experimenter's voice, then the hum of the transformer and, finally, the noise of the film camera, that is, everything that happened around the animal and what it heard.
Scientists have discovered that dolphins have a wealth of sound signals and actively communicate with each other using a wide variety of sounds - frequent tonal whistles, sharp pulsating sounds - clicks. Dolphins have up to 32 different complex sound signals, and it is noted that each dolphin has its own characteristic whistle - “voice”. When alone or in a group, dolphins exchange signals, whistle again, make clicks, and when one dolphin gives a signal, the other is silent or whistles at that moment. When communicating with her calf, the female dolphin makes up to 800 different sounds.
Communication between dolphins occurs continuously even if they are separated, but can hear each other. For example, if you isolate dolphins and keep them in different pools, but establish radio communication between them, they will mutually respond to the emitted signals of the “interlocutor”, even if they are separated by a distance of 8000 km. Are all the sounds dolphins make real spoken language or not? Some scientists believe that this has already been indisputably proven, others are more cautious about this possibility, believing that the sounds of dolphins reflect only their emotional state and express signals associated with searching for food, caring for offspring, protection, etc.
The “speech” of dolphins in the form of whistles, clicks, grunts, squeaks, and shrill screams is not a special coded communication system that would correspond to human speech. True, one analogy suggests the opposite idea: residents of villages in some mountainous places in the Pyrenees, Turkey, Mexico and the Canary Islands communicate with each other over long distances, up to 7 km, using a whistle. Dolphins have a whistling language that is used for communication and only needs to be deciphered.
A dog's life and language
It is known that dogs are the most popular among pets. The old concept of “a dog’s life” in the sense of hopelessness, life’s hardships and inconveniences is gradually taking on a completely different coloring.
significant differences in the structure of the brain and vocal apparatus.
The famous trainer V.L. Durov loved animals, studied their habits well, and perfectly mastered the skill of teaching and training animals. This is how he explained dog language. If a dog barks abruptly - “am!”, looking at a person and raising one ear at the same time, this means a question, bewilderment. When she raises her muzzle and utters a drawn-out “au-uh-uh...”, it means she is sad, but if she repeats “mm-mm-mm” several times, then she is asking for something. Well, a growl with the sound “rrrr...” is clear to everyone - it’s a threat.
I also conducted my own observations on my dog and came to the following conclusions:
The dog is angry - it barks and growls angrily, while baring its teeth and pressing itself to the ground. It is better not to approach such a dog.
The dog is scared - it tucks its tail and ears, tries to look small, and may even hug the ground and crawl away. Also, if the dog is nervous or afraid, it will not look you in the eyes. This is what a guilty puppy usually does.
Exercise : use sound signals to determine the name of the animal and write it down in your notebook.
4. Consolidation of knowledge.
Frontal conversation.
1.What are signals and sounds in animals?
2. Does sound signaling exist in all species of animals or not?
3. Is it possible to determine its behavior and desire by the sound signals of a dog? Give examples.
Homework assignment : Prepare answers to the questions at the end of the information on the handout.
In Nature, everything is interconnected and therefore the behavior of some individuals directly depends on the behavior of others. So, for example, a flock of waders that is feeding on the shallows will immediately take off if one sandpiper rises into the air. And, the warning cry of one of the geese of a large school will lead to the flight of all the birds. Also, the quack of a duck can attract a drake that flies past at a distance. It turns out that birds have their own language, with the help of which they communicate and understand each other. Continuing our series of articles about the life of birds (find out details about here), we invite you to talk about just this today...
The language of birds and its meaning for birds
It is fundamentally wrong to fall into anthropomorphism and try to humanize the language of animals. The mechanisms of communication in birds are different from communication between people. And we shouldn’t forget about this difference. Therefore, it would not be correct to think that a chicken that sees a flying goshawk makes threatening sounds because it wants to warn other chickens about the danger. Rather, her cry is an unconscious response, a natural reaction to the appearance of an enemy. A similar reaction triggers escape mechanisms in this bird. But other chickens, who do not see the hawk, but hear the chicken’s cry, still react to it and run away. Moreover, for them the irritant is not the hawk itself, but the behavior of the first hen and her cry.
It is noteworthy that, finding itself in such a situation, even a chicken that is completely alone will scream. It turns out that her behavior and screams are a manifestation of unconscious instincts? It is quite possible, and they are the ones unconscious instincts are one of the most important biological adaptations that allow a species to quickly escape from enemies, find food, and generally coordinate the actions of its bird community or flock. This is precisely the important task of animal language, which provides all the main aspects and aspects of existence - the processes of nutrition, migration, reproduction...
Therefore, the very essence of the language of birds and animals can be explained very simply - this the reaction of one living organism to a stimulus that is understandable to another living organism. And it is the demonstration of such a stimulus that can cause a reaction in another animal. Thus, a connection and communication is formed between different animals of the same species. And the stimulus itself, which acts as a connecting link, serves only as a signal or trigger for such joint actions.
Types of bird sounds
At the same time, the signals that can be used by animals and birds to communicate with each other can be very different. These include trace marks, scents of the female, postures, bright spots of color. And of course, the various sounds that birds make are of great importance in this general behavior. Thus, the quiet whistle of a hazel grouse (find out how to cook it deliciously - look for a recipe) can attract other hazel grouse, and the voice of a female quail causes a response in the males of this species. The squeak of grouse chicks, which run in thick and tall grass, allows their mother to find her brood, and the grouse do not get lost and run away.
Bird language tools
The sense organs that receive sound signals serve as channels through which communication between birds is directly carried out, and they are the main instruments of animal language. As a rule, those signals are usually used that are closely related to the sense organs and are most developed in this group of animals. For birds it is vision and hearing, but for mammals it is hearing and smell. At the same time, the nature of the connection itself must strictly correspond to the peculiarities of the biology of the species. So birds, as flying creatures and leading an open lifestyle, must be able to respond in a timely manner to extraneous stimuli that are located at a great distance from them, long before approaching such stimulus objects. Therefore, it is appropriate to consider that
The basis of communication between birds is precisely visual stimuli, which are supplemented by sound ones in situations where the possibility of visual perception is limited.
Mechanisms for producing sounds by birds
Birds have special mechanisms for producing sounds. They have an instrumental or mechanical voice that is closely related to structures that are found on the surface of the bird's body. Therefore, it is not surprising that the plumage of birds is often involved in the production of sound. Thus, snipe, well known to our hunters, are capable of causing sound vibrations with the help of their outer tail feathers, which are somewhat narrowed and look like hard fans. At the same time, the bleating of a snipe can be safely regarded as its mating. And, some ornithologists even believe that the rattling sounds that the snipe makes during its flight are caused not by its tail feathers, but by the feathers of its wings. Many chickens also have their own method of courtship between a male and a female. This is clearly seen in the example of domestic chickens. The rooster forcefully lowers its wings and runs its paw along the hard flight feathers, as a result of such actions a characteristic cracking sound occurs. The sharp and long growth that roosters have, called a spur, is also involved in the process of producing current sounds.
Science has also proven that the whistling sounds that occur during the flight of some ducks (they arise as a result of friction of air currents against the hard feathers of the duck) also have their own signal value. These sounds are clearly audible even at a distance, and the human ear is able to catch them at a distance of 30 meters or more. By the way, from such instrumental characteristic sounds a good hunter can easily distinguish which birds are flying.
Often in the spring in the forest you can hear a woodpecker drumming; it produces this sound with the help of frequent and strong blows with its hard beak on dry wood. A resonance occurs in a dry tree, and the sound intensifies and spreads far throughout the forest. In order to intensify such drumming, the woodpecker can specifically select individual sharp branches with a pointed top. The latter serve as a kind of natural device for recording and amplifying sound. It is also interesting that different species of woodpeckers drum at different frequencies, regardless of their gender. And, their fraction serves as a way for these birds to recognize each other.
The flapping of wings is also of great importance in signal language. It can be done both on the ground - when birds are mating, and in the air. Often, the knocking of beaks or legs can also cause responses in other birds. You can check this yourself. The chickens run when they hear a light tapping on the board, and they perceive this as a signal to get food. It is noteworthy that for adult chickens the meaning of this signal remains the same.
Voice of the birds
And although instrumental sounds can be found in many groups of birds, their importance is actually not that great. Still, the main load in birds is carried by their real voice, in other words, these are the sounds that birds produce with the help of their larynx. The sound spectrum of these sounds is quite large and several times greater than the spectrum of the human voice. So, for example, if you listen to the mating cry of a long-eared owl, it sounds at a frequency of 500 Hz, and the sounds that small passerines make include ultrasonic frequencies up to 48 thousand Hz, and naturally the human ear can no longer hear them.
Bird calls
The very set of bird sounds that a person can hear includes up to hundreds of cries, melodies, calls, stanzas, which differ in intensity, frequency, timbre, and so on. The American bird, close to our cranes, called the siriema, has the ability to reproduce up to 170 different sounds, however, songbirds have an even wider range of sound capabilities.
There are various life situations in which birds make certain identical sounds that are associated with feeding, feeding chicks, reproduction, nesting, mating, and so on. Thanks to the use of modern sound recording equipment and modern developed physiological methods, humans have a unique opportunity to finally decipher the semantic and biological meaning of some bird signals.
Dr. Skorpe and England spent a lot of time on this decoding, and he managed to find out that finches have 5 signals associated with information assessing the environment, 9 signals relate to relationships within the flock and the nesting period, 7 signals have an identification meaning and 7 relate to orientation in space. Well, the pied flycatcher has up to 15 signals deciphered by humans, while the common bunting has 14, the same number of signals were deciphered from the tongue of the blackbird.
The meaning of bird calls
At the same time, the very deciphering of the biological meaning of bird signals allows us to count on the fact that in the case of accurate reproduction of such sounds, a motor response of a nature that can be predicted in advance can be obtained in response. So, for example, if you let a tit listen to a signal that stimulates its immediate takeoff, and then scroll through the signals to stop the flight, then in this way you can control the bird’s movements in the air.
Whereas, imitation of the cry of chicks begging for food can cause adult birds to move towards the source of the sound.
Below we provide a list of those signals whose biological significance cannot be doubted.
Signal of satisfaction
It is a long, quiet squeak that is often emitted by chicks of chickens and other brood birds. This is how warm and well-fed chickens often squeak. Chicks of gulls, waders and some species of ducks similarly show their satisfaction. The sign is a signal and a small passerine.
Begging signal
It is emitted by chicks fed by their parents - passerines, gulls, auks... Moreover, such a signal can be of 2 types. The first can be attributed to the smallest chicks, which emit it when they see food and parents, the second is more typical for fledglings and they emit it during the absence of their parents. Chicks do this so that adult birds can find them. By the way, this signal allows the chicks to stay together.
Fokin S.Yu. Acoustic signaling and biological basis for controlling the behavior of birds during artificial game breeding // Game breeding in hunting. Collection of scientific works of the Central Scientific Research Laboratory of Glavokhoty of the RSFSR. Moscow, 1982. pp. 157-170.
ACOUSTIC SIGNALING AND BIOLOGICAL BASIS OF BIRD BEHAVIOR CONTROL IN ARTIFICIAL WILDLIFE BREEDING
The possibility of using bioacoustics in hunting was first pointed out by V.D. Ilyichev (1975) and A.V. Tikhonov (1977). However, special research was started only recently, at the Central Research Laboratory of Glavohota of the RSFSR. They will help solve a number of complex problems facing domestic game breeding and increase its efficiency. Until now, in the hunting industry, sound communication between animals has been used only when hunting game using the luring method and when counting some animals by voice. However, the study of the sound signaling of birds has shown the fundamental possibility of using it in controlling the behavior of birds.
The development of methods for controlling the behavior of birds is based on knowledge of individual behavioral acts and vocal reactions of birds in the behavioral complex characteristic of a given species. The basis of bird communication is acoustic and visual communication, which have a close relationship. The complexity of the organization of acoustic signaling systems in birds is manifested in the presence of two basic principles for encoding information in signals. On the one hand, this is multifunctionality (Simkin, 1977), in which the same acoustic signal has several functions (for example, bird song serves to mark the nesting territory, “scare off” other males, but at the same time to attract females and even to divert the enemy from the nest). On the other hand, this is parallel coding, according to which different types of signals convey similar information (Simkin, 1974), for example, various comfort signals of chicks reflect the same comfort situation. The dominance of the emotional principle over the semantic principle in many cases makes it difficult to analyze the acoustic signaling systems of birds. However, in most brood birds, acoustic signals are more often associated with a certain functional significance, especially during the nesting period and during the movement of broods (Tikhonov and Fokin, 1931). The specific organization of sounds (tonal, noise and trill signals) is associated with the most rational range of their propagation (Ilyichev, 1968; Simkin, 1974).
Attempts to classify bird signals have been repeatedly made by various researchers. The main difficulty is that it is impossible to identify the mechanism of language in birds and humans, since the logical foundations of the communicative processes of animals are fundamentally different (Simkin, 1932). A.S. Malchevsky (1972) divides the sound signals of birds into 2 main types: situational and signaling. In the first case, communication occurs with the help of signals that have an expanded meaning depending on the biological situation. In the second, a system of specialized sound reactions is used, and the signals associated with a certain physiological state of the bird have a strictly defined biological meaning. This type can be classified according to functional characteristics. The author identifies calling and protective signals with a detailed classification of each group (Malchevsky, 1974).
G.N. Simkin (1977) proposed a new scheme for the functional classification of acoustic signals of birds, based on the maximum differentiation of signal values. He divided all sound signals into 3 main groups, each of which includes smaller categories:
1. The main urges given throughout the year: the main species calling cry, school and group urges, food signals, alarm signals, conflict signals, special signals of the emotional sphere.
2. Urges of the reproductive cycle: mating phase, parental phase.
3. Calls of chicks and fledglings.
Parental signals of brood birds are usually divided into “following call”, “food call”, “gathering signal”, contact signals, alarm signal (in chicken birds the signals for air and ground enemies are different).
We proposed dividing the acoustic signals of chicks into 3 categories (Tikhonov and Fokin, 1980).
1. Signals of a negative physiological and social state, including signals of “discomfort,” indicative and nutritional.
2. Signals of a positive physiological and social state, subdividing them into signals of “comfort”, warming, saturation, group contacts, following, pre-sleep
condition.
3. Alarming and defensive signals (anxiety, distress, fear).
Such a fractional classification forms the basis for solving many problems of controlling the behavior of birds in game breeding. Knowing the basic functional meaning of a signal characterized by certain physical parameters, one can pose the inverse problem, studying the influence of this signal on the behavior of birds.
The bird makes its first sound signals while still in the egg, 1-2 days before the shell hatches. In the auditory analyzer of chicks, first of all, those nerve cells that are “tuned” to the species-specific frequency of the female’s voice mature (Anokhin, 1969). Sound communication between the female and the chicks is established already at the end of incubation (Tikhonov, 1977). Indirect learning in brood birds, including signal succession and group learning (Manteuffel, 1980), plays an important role in the ethological preparation of young birds for independent life. Of particular importance is the acoustic behavior of parents as a factor in stimulating and polishing the behavior and communication of young birds in the brood (Simkin, 1972).
In artificial game breeding, humans deprive the chicks of contact with the female. Incubation of eggs, cage and cage rearing of young animals without brood hens leads not only to the impossibility of developing adaptive behavioral reactions that are formed in nature on the basis of individual and group experience, but also to the extinction of some important innate behavioral acts, in particular anxiety reactions. Our experiments on mallard ducklings showed that the innate reaction of flight in chicks to alarming signals from the female is most clearly manifested on days 2-3 and, without visual reinforcement, fades away already on the fifth day. When strengthened by special “scare sessions” (loud screams, shots, sirens, special scaring by people), the alarming reaction persists until release into the wild. Subsequently, it becomes an integral component of the behavior of released birds.
However, the use of special “scares” is not the main factor in the formation of a “wild” behavioral stereotype in birds raised in captivity. As is known, birds raised in constant contact with humans differ sharply in behavior from their wild relatives. Such birds do not have directed alarm-defensive reactions to predators, which makes them easy prey for both ground and air enemies. Hunting for birds that are not afraid of humans loses its sporting interest and even becomes inhumane.
The main factor in birds becoming accustomed to humans is the effect of imprinting (imprinting) the appearance and voice of a person on the chicks during the “sensitive” period, limited to the first 2-3 days of life. In the future, the positive reaction to humans is further enhanced due to the formation of conditioned reflex reactions in the process of feeding and constant communication with birds. Imprinting is an extremely persistent and practically irreversible process. Therefore, in our opinion, when artificially breeding game, it is necessary to prevent human imprinting on chicks in the “sensitive” period. We conducted a series of experiments consisting of isolating small ducklings from humans at different periods. The experimental cages with houses were curtained on all sides with dense material, and the top remained open. During feeding and changing water, the chicks saw only the hands of the person serving them, and in the process of giving food they always ran into the house. Ducklings isolated from humans for a “sensitive” period subsequently became accustomed to them, but on the basis of conditioned reflex reactions. Special methods of “scare” after releasing them into the grounds (shots from guns, etc.) contributed to the disruption of these positive conditioned reactions: the ducks began to be afraid of people. And yet, their flight reaction in response to the appearance of a person was more sluggish than that of their wild relatives. At the same time, ducklings raised in the usual way reacted indifferently to the appearance of people.
The best option turned out to be keeping the ducklings in isolation from humans for the entire time, right up to their release onto the land, i.e. up to 25-30 days. Such ducks were practically no different in behavior from wild ones: they flew away when a person approached, they were afraid of unfamiliar objects, air and ground enemies, and even “peaceful” birds. Hunting such game was practically no different from hunting wild birds.
Currently, our main task is to search for a technical implementation of this method of raising young game birds, taking into account the specific design of game farms. Obviously, you need to start with strict adherence to the following requirements. During the hatching period, complete silence must be maintained in the incubator to avoid the chicks imprinting human voices. For the first 5-7 days, the hatched chicks are transferred to brooder cages, covered on all sides with dense material, which should be folded back at the door when feeding and changing water. Then the young animals are transferred to enclosures with walls covered with plywood or roofing felt and raised for up to 25-30 days. During the growing process, it is very effective to carry out 4-5 “scares” after releasing young nyak onto the land. On the second day after release (but not on the day of release), several people come to the place where the released game is kept and fire several blank shots, achieving a flight reaction in the birds. Birds that have been isolated from people for a “sensitive” period, unlike those raised in constant contact with humans, are afraid of gunshots. The combination of a shot and the appearance of a hunter produces a negative reaction in birds towards humans. Already 3-4 days after regular scares, the mere appearance of a person, for example, near a pond, causes the flight of young ducks, who try to hide in the thickets.
Ducks released at a later age are more difficult to run wild, and if in the first days of life the chicks were not isolated from people, then such birds, as a rule, practically do not react to shots. Feralization passes faster if the birds have seen the death of their fellow bird several times after the shot (Ilyichev and Vilke, 1978). You can teach birds to avoid people using the principle of combined repellents - that is, use not only direct human cries and gunshots, but also recordings of various sounds - distress cries, alarms, sudden takeoff of a flock of birds, high-intensity sounds (up to 120 dB), ultrasounds ( up to 40 kHz) (Tikhonov, 1977). However, our hunting farms are not yet equipped with special equipment for using these methods and there is no point in stopping at them yet.
In the practice of game breeding, there is a need to collect chicks in a certain place. During the sudden onset of bad weather, small chicks hide in open enclosures at night and may die from hypothermia. The maintenance personnel of game nurseries are forced to drive them into shelters. Sometimes it becomes necessary to transfer young animals from one room to another, collect them in a certain place for weighing, dividing into groups, etc. Such work can be facilitated by using acoustic attractants - sound attractants. The following reaction of a single chick has been studied quite fully, but in game breeding we are dealing with large groups of chicks, and practically no experiments have been carried out to study the following reaction of a group of chicks.
Chicks of brood birds are characterized by an approach reaction in response to the calling signals of the female or her imitators - monotonous signals (Malchevsky, 1974). Single chicks were offered recordings of sound signals of different functional significance. They responded with an approach reaction to juvenile comfort signals and female calling signals. The use of these two signals and their monofrequency imitators as attractants for a group of chicks was initially unsuccessful. In our opinion, the lack of reaction in a group of chicks approaching the sound source is due to two reasons. Firstly, the level of motivation of the chicks plays a decisive role in stimulating this reaction. A chick, isolated from its brethren, experiences constant discomfort, which prompts it to respond by approaching certain sound signals. And in our experiments, the chicks were in comfortable conditions - they were close to their brothers. In nature, comfortable conditions for chicks are created by the female, and in artificial conditions - by humans. The chicks only imprint on each other and people; the need for constant contact with the female disappears. Naturally, in artificially created comfortable conditions, the chicks will not have an approach reaction, since sound signals alone are not enough, and they do not have the corresponding internal factors (state of discomfort). Second, as shown by Gottlieb (1977), an acoustic-visual stimulus evokes a more powerful pursuit response than an acoustic stimulus alone. In nature, birds following their mother are guided by both her appearance and her voice. In artificial conditions, the chicks “do not know” the female, and the object of their imprinting may be the first moving sounding object seen in life.
It follows that the motor reactions of chicks can be controlled in two ways: either by using acoustic attractants in uncomfortable situations (cooling, hunger), or by using acoustic-visual attractants (moving sounding speakers), having previously ensured that the chicks imprint them. Our experiments fully confirmed this (Fokin, 1981). For example, small ducklings that did not respond to the reproduction of the duck’s calling quacks quickly gathered near the speaker after turning off the lighting and heating in the brooder; The baby pheasants actively followed a moving speaker through which recordings of their comfort calls were played.
With an increased density of chicks, an increase in their aggressiveness is observed, manifested in collisions at feeders and drinkers, pecking, and restlessness. This has a depressing effect on their growth and development. Industrial noise also has a negative impact on the life activity of birds (Rogozhina, 1971). Phelps (1970) discovered a calming effect of music on the behavior of laying hens, with an even greater effect observed when hens played recordings of their comfort calls. As experiments on chickens (Ilyichev and Tikhonov, 1979) and quails (Fokin, 1981) showed, the use of monofrequency signals of the appropriate frequency led not only to “calm” the chicks, but also significantly increased their feeding activity. Feed consumption increased, and daily weight gain increased sharply. Thus, the weight of experimental quail reached an average of 147.7 g by the age of two months, while control chicks of the same age reached only 119.6 g.
We also used comfort signals from chicks and females as stimulants. A good effect is achieved by periodically playing food sounds of non-vocal origin that accompany feeding (the beak striking the substrate, the alkalization of water, etc.).
Currently, intensive research is being conducted to develop optimal modes for stimulating young animals with sound signals. It is known that in spring current sounds stimulate the growth of the gonads of birds (Promptov, 1956). In addition, most species are characterized by the phenomenon of sound induction, the essence of which is that the species’ mating song stimulates similar sound responses in males of the same bird species (Malchevsky, 1982); Brockway (Brockway, 1965) notes that voicing In birds, mating signals stimulate the process of oviposition.
Our experiments on stimulating mallard ducks, wood grouse, black grouse and chukars kept in the game nursery of the Central Scientific Research Laboratory with current sounds showed the important role of sound induction in the mating behavior of birds. In grouse and chukars, artificial sound induction disrupted the species-specific circadian rhythm of displaying, “forcing” them to display during the day, even in inclement weather. Playing recordings of the mating call of a male Japanese quail in a sparrowhawk led to an increase in the sound activity of all males: the number of mating calls emitted per hour by all males in the sparrowhawk increased by 1.8 - 2.0 times, and the number of matings also increased. Obviously, sound stimulation contributes to an increase in the egg production of birds. In any case, in our experiments, the total number of eggs laid in the first days of voicing increased by 36–47%. Then, a drop in egg production occurred, which can obviously be explained by the effect of birds becoming accustomed to constant external stimuli.
These areas do not limit the range of exploratory studies of the practical use of bioacoustics in game breeding. The distinctive features of the voices of domestic subspecies of common pheasant are studied, the role of sound reactions in the formation of pairs in geese and geese, which are characterized during the breeding season by the so-called antiphonal duets, also characteristic of some cranes, owls and passerine birds, is clarified (Malchevsky, 1981). Methods of catching wild birds in nature using “acoustic traps” are being explored.
Express methods for determining sex by voice in day-old young game birds are being developed, and research is underway on acoustic stimulation and synchronization of hatching of chicks.
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