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Information × Registration Number 0211U002885, 0107U000083 , R & D reports Title The research of processing mechanisms of acoustic information in the auditory system of dolphin and ethology aspects of problem of black sea dolphins population maintenance in the wild and ethology readaptation of animals to the natural environment at rehabilitation measures popup.stage_title Head Polyakov M.A., Registration Date 09-03-2011 Organization Karadag Natural Preserve National Academy of Sciences of the Ukraine popup.description2 Report on SRI 140 pages, 22 pictures, 4 tables, 270 sources. The way of echo transmission on middle ear of a dolphin (passing alvearies) through chin channels and mandibular channel of bottom jaw is considered . The executed calculations confirm that morphological structures of bottom jaw are components of the specialized peripheral department of echolocation hearing, that from the point of view of acoustics is optimal. The obtained results show, that the peripheral department of echolocation hearing conducts on the middle ear sounds only echolocation range of frequencies (40-140 кГц), but low frequency sounds and of communication sings in a range up to 30-40 кГц passed another way. In the process of secondary adaptation of cetacean to the aquatic environment a set of functional and morphological changes happened. To that, presumably, it is possible to add the specialized peripheral department of hearing, very expediently occupying a bottom jaw. With the use of methods of instrumental pavlovian reflexes with a food reinforcement the ultimate angles of sound source localization by a dolphin were measured in a vertical plane in an aquatic environment. For voice-frequency pulses by duration 1 s, at frequency 5, 20 and 120 кГц, the ultimate angles of localization ware founed 2-2,50, and for an impulsive click with bearing frequency 120 кГц about 1,500. It specifies that for the direction-finding of different acoustic signals source dolphins use different, but identically effective physical pre-conditions. The preliminary results of the field researches showed that Karadag natural reserve is occupied important position in the center of south-east coast of Crimea. The migratory ways of dolphins lie near-by him, and also there is reproduction and wintering of cetacean. In this connection monitoring works on the base of reserve have the special value. Supervisions and accountings will allow to specify the dynamics of presence of animals during a year and their spatial distribution, the study of extrass ashore will allow to judge about fluctuation level of death rate and reasons of destruction of animals. A closeness to the focis of fishing in Crimea (Kerch, Feodosia) dictates the necessity of creation of regional dolphins rehabilitation center. DOLPHIN, HEARING, SPECTRUM, FREQUENCY, ECHOLOCATION, SOUND CONDUCTION, LOCALIZATION, POPULATION, MAINTENANCE, REHABILITATION. Product Description popup.authors Бабушина Е.С. Гладилина Е.В. Кривохижин С.В. Рябов В.А. popup.nrat_date 2020-04-02 Close