FORMS OF PRE-CAUCASIAN BROWN TROUT S. TRUTTA CAUCASICUS (DOROFEEVA, 1967) OF THE CASPIAN BASIN
Abstract and keywords
Abstract (English):
A morphological analysis of brooks trout in Dagestan showed that each spawning herd is morphologically unique and differs from the rest in a certain set of characters. However, all of them, when comparing the age composition, spawning conditions, the extent of spawning migrations in rivers, etc. have a lot in common. All of them meet the definition of a population as a group of individuals united by panmixia, a single territory and isolated to one degree or another from similar groups within the species. The morphological characteristics of trout in the upper of rivers Avar, Andi, and Kara-Koysu further confirms the validity of this approach. Presumably, the structure of trout populations is in continuous change and the differences in morphological indicators are phenotypic in nature and reflect the biotic and abiotic conditions prevailing in this region. The interaction of variability and selection in the population maintains a mobile equilibrium of biological properties forms the passing (brown trout) and residential (trout) forms. The trout of Sulakriver breaks up into several local herds (trout of Avar Koysu, Andi Koysu, Kara-Koysu, etc.) with a specific and limited range of its migrations. To a certain extent, differing from neighboring ones, each of the herds maintains its integrity and does not mix with the rest. Thus, the brooks trout of Dagestan seem to combine two functions - the self-reproduction of local settled populations and generating migrant individuals in the Caspian trout (Terek, Samur, Kara-Su rivers, etc.). In the rivers of the Kara-Su system, regardless of the place of fishing and the season, trout is represented by almost 100% males. Naturally, the question arises: who ensures the reproduction of trout herds in the absence of females? At the same time, the Salmo truttacis caucasicus (Dorofeyeva, 1967) comes to spawn in these rivers, and its livestock is represented exclusively by females (70-80%). Therefore, brooks trout of the Kara-Su system rivers and the Salmo truttacis caucasicus, coming here to spawn, should be considered as a single reproduction fund. Eggs, laid by either a brown trout female or a trout female, can leave individuals, that roll into the sea and turn into a passing trout, and individuals that remain in the river will be called brooks trout. The total reproductive potential of small rivers of the Dagestan coast of the Caspian Sea is currently no less than in native salmon rivers (Terek, Samur). That is why small rivers play an important role in the natural reproduction of trout and brown trout. Among the small salmon rivers of Dagestan, the greatest fishery value have tributaries of the Sulak river, rivers of the Kara-Su system, Shura-ozen, Manas-ozen, etc. Significant differences in the climatic features of these areas inevitably affect the biology of trout inhabiting them.

Keywords:
salmon, brown trout, incubation of eggs, broodstock, smoltification
References

1. Abakumov V.A. Lokal'nye narusheniya reproduktivnoj izolyacii mezhdu lososem i kumzhej // Trudy VNIRO. M. 1971. V. 42. Pp. 167-169.

2. Berg L.S. Ryby presnovodnyh vod SSSR i sopredel'nyh stran // M. 1948. Part 1. Pp. 159-172.

3. Barannikova I.A. Funkcional'nye osnovy migracii ryb // L. Nauka. 1975. 210 p.

4. Vladimirov V.I. O proiskhozhdenii forelej Zakavkaz'ya // Izd. AN Arm.SSR. 1944. №1. Pp. 145-146.

5. Derzhavin A.N. Kaspijskij losos'. Sbornik, posvyashchennyj pamyati N.M.Knipovicha // M. Izd. AN SSSR. 1939. Pp. 187-203.

6. Demin D.Z. Vysokogornoe forelevoe ozero Dzhenekh // Tr. Dag. sel'hoz. ins-ta. Mahachkala. 1949. V. 4. Issue 1. Pp. 153-156.

7. Kichagov A.L. Vyrashchivanie ruch'evoj foreli v more // Rybnoe hozyajstvo. 1937. V. 4, P.12-

8. Osinov A.G. K voprosu o proiskhozhdenii sovremennogo areala kumzhi Salmo trutta L. (Salmonidae), (Dannye po biohimicheskim markeram genov) // Vopr. ihtiologii, 1984, V. 24, Issue 1. Pp. 11-13.

9. Pravdin I.F. Ruch'evaya forel' v pritokah Ladozhskogo ozera // Izv. Karelo-Fin.fil. AN SSSR №2. 1949. №3. P. 56.

10. Protasov A.A. K voprosu o proiskhozhdenii kaspijskogo lososya // Inf. sb. VNIRO, 1960. №9. Pp. 10-19.

11. Reshetnikov YU.S. Izmenchivost' ryb i ekologicheskoe prognozirovanie // M. Nauka. 1979. Pp. 1-3.

12. Saidov YU.S. Dagestanskaya forel' // Priroda, 1963. №4. Pp.97-99.

13. Savvaitova K.A. O strukture vida u ryb vysokih shirot // Sovremennye problemy ihtiologii, M., Nauka, 1981, Pp. 106-108.

14. Terent'ev P.V. V zashchitu vida kak konechnogo taksona // Zool.zhurnal, 1968, V. 17, Issue 6, Pp. 890-892.

15. Magomedov G.M. Sistematika, ekologiya i kul'tivirovanie lososevyh ryb Dagestana i sopredel'nyh territorij // M. 2007. Pp. 12-15.

16. Fortunatov M.A. Foreli Sevanskogo ozera Salmo ischchan Kessler // Tr. Sevansk. ozern. stancii, 1927., V. 1, Issue 2, 131 p.

17. Fortunatova K.R. Foreli ozera Gel'-Gel' // Trudy Sevansk. gidrobiol. stancii, 1929, V. 1, Issue 2, 68 p.

18. Fortunatova K.R. Foreli ozera Ejzenam // Trudy Sevansk. ozern. stancii. Tiflis, 1933, V. 3, Issue 2, Pp. 73-76.

19. SHaripov K.O. Antropogennye osobennosti kaspijskogo lososya i ruch'evyh forelej rek Tereka i Sulaka // Vopr. Ihtiologii, 1970. V. 10, Issue 4(63), Pp. 761-765.

20. SHaripov K.O. Imunno-serologicheskie osobennosti sevanskih forelej v svyazi s ih klassifikaciej // Zool.zhurnal, 1975, V. 54, Issue 11, Pp. 1731-1733.

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