Anadromous sturgeon fish of the Azov Sea under conditions of natural and anthropogenic transformations of the water ecosystem

The aim: assessment of the state of populations of anadromous sturgeon in the Sea of Azov, the efficiency of their reproduction and the possibility for the existence of populations in the medium term until 2030–2040. Methods: the calculation of the biomass and population size of sturgeon in the Sea of Azov was carried out using the direct counting method and a modified cohort solution of the Baranov equation. 18and 25-meter bottom trawls were used as standard fishing gear. The assessment of the number of juvenile sturgeon in the Don River was carried out with 3and 2-meter beam-trawls. Molecular genetic methods for the analysis of microsatellite loci and sequencing of a fragment of the control region of mitochondrial DNA were used.

Novelty: materials are presented on natural reproduction of sturgeon in the Don River after flow regulation, and the rate of decline in the survival rate of generations of Russian sturgeon and stellate sturgeon under the influence of illegal fishing is shown. Based on the results of a study of the genotypes of Russian sturgeon individuals, migrations sturgeon from Azov to the Black Sea, as well as Black Sea populations to the Sea of Azov, were confirmed.

Results: an analysis of the dynamics and current state of anadromous sturgeon in the Sea of Azov is presented under the conditions of anthropogenic transformation of their habitat, loss of natural reproduction and climate-related fluctuations in the salinity of the sea waters. A retrospective overview of their commercial use from the mid-19th century to the present is given. The prospects for restoring commercial stocks of sturgeon fish are considered.

Practical significance: the possibility of restoring commercial stocks of sturgeon in modern conditions is shown by increasing the number of released juveniles and increasing the effectiveness of fish conservation measures to a level of more than 90 thousand tons and creating an commercial population of sturgeon in the Sea of Azov.

1. Avedikova T. M. 1978. Migrations, growth and abundance of underyearlings of beluga in the Sea of Azov // Trudy VNIRO. V. 131. P. 70–82 (In Russ.).

2. Averkiev F. V. 1941. Current state of the fishing industry of the Azov-Black Sea basin // Proceedings of the Don-Kuban scientific fish farm stations. V. 8. 63 p. (In Russ.).

3. Averkiev F.V. 1960. Collection of statistical information on catches of fish and non-fish objects in the Azov-Black Sea basin for 1927–1959 // Trudy AzNIIRKH. Rostov-on-Don. 75 p. (In Russ.).

4. Aksyutina Z. M. 1968. Elements of mathematical evaluation of observational results in biological and fisheries research. Moscow: Food Industry, 288 p. (In Russ.).

5. Balandina L. G. 1977. Biological justification for fishing for pikeperch and sturgeon in the Sea of Azov, taking into account changes in their stock and habitat conditions. Ph.D. abstr. in biology. Moscow: VNIRO. 24 p. (In Russ.).

6. Baranov F. I. 1918. On the question of the biological foundations of fisheries // Izv. Department of fish farming and scientific fishing. research. V. 1. Iss. 2. P. 84–128. (In Russ.).

7. Belyaeva V. N., Boldyrev I. I. 1968. Survival of sturgeon at early stages of development in conditions of different salinity // Biological justification and principles of placement of hatchery juvenile sturgeon in water bodies. Astrakhan: TsNIORKh, Volga. P. 151–162. (In Russ.).

8. Bulgakova T.I., Kulba S.N., Pyatinsky M.M. 2022. Modeling scenarios for the restoration of the stock of Russian sturgeon Acipenser gueldenstaedtii in the Azov Sea in the absence of natural reproduction // Journal of Ichthyology. V. 62. No. 2. P. 198–208. DOI:10.31857/S0042875222020047. (In Russ.).

9. Volovik G.S., Volovik S.P., Kosolapov A.E. 2009. Water and biological resources of the Lower Don: state and management problems: Novocherkassk: SevKavNIIVH. 301 p. (In Russ.).

10. Gorelov V.K. 1969. The influence of sea water of different salinity on the osmotic pressure of the blood and the survival rate of the beluga x sterlet hybrid // Materials of the session of the TsNIORKh, dedicated to the 100th anniversary of sturgeon breeding. Abstract. Report. Astrakhan. P. 48–50. (In Russ.).

11. Gorodnichy A. E. 1957. The state of the sturgeon fishery in the Sea of Azov and the ways of their natural reproduction // Fisheries. No. 7. P. 56–60. (In Russ.).

12. Dubin V. P. 1972. Euryhaline of juvenile stellate sturgeon in the early stages of ontogenesis // Proc. reporting session of TsNIORKh. Astrakhan. P. 50–51. (In Russ.).

13. Doynikov K. G. 1936. Materials on the biology and assessment of sturgeon stocks in the Azov Sea // Works of the Don-Kuban Scientific Fishery Station. V. 4. P. 3–213. (In Russ.).

14. Doinikov K. G. 1939. Improve the regulation of the Azov sturgeon fishery // Fisheries. No. 11. P. 20–21. (In Russ.).

15. Karpevich A.F. 1960. The influence of changing river flows and the regime of the Azov Sea on its commercial and food fauna // Trudy AzNIIRKh. V. 1. Iss. 1. P. 3–113. (In Russ.).

16. Kasimov R. Yu., Abramov B. N., Kyazimov I. B. 1966. The influence of water of different salinity on the survival and growth of sturgeon of Kura in the early stages of development // Trudy Azerbaijan Branch of the TsNIORKh. V. 4. No. 2. P. 91–95. (In Russ.).

17. Kovtun I.F., Korneev A.A., Syrovatka N.I. 2005. Methods for assessing the efficiency of reproduction of commercial fish in the AzovDon region // Methods of fishery and environmental research in the Azov-Black Sea basin. Krasnodar: Prosveshcheniye-Yug. P. 123–129. (In Russ.).

18. Kozlitina S. V., Volovik S. P., Dubinina V. G. Nechepurenko I. G., Volovik G. S. 1998. Modeling the requirements of fisheries to the water regime of the river. Don. // Basic problems of fisheries and protection of fishery reservoirs of the Azov-Black Sea basin. Proceedings of AzNIIRKH (1996–1997). Rostov-onDon. P. 357–371. (In Russ.).

19. Korneev A. A., Baskakova T. E. 1984. Results of sturgeon reproduction under conditions of regulation of the Don flow // Reproduction of fish stocks of the Caspian and Azov seas. Moscow: VNIRO Publish. P. 54–62. (In Russ.).

20. Korneev A. A., Kovtun I. F., Syrovatka N. I. 2004. Current state of natural reproduction of anadromous and semi-anadromous fish in the Azov-Don region // Abstr. of reports intern. scient. conf. «Problems of natural and artificial reproduction of fish in marine and freshwater reservoirs». Rostov-on-Don: TSVVR. P. 70. (In Russ.).

21. Korneev A.A., Luzhnyak V.A. 2015. Ecological features of juvenile Russian sturgeon Acipenser gueldenstaedtii (Acipenseridae, Acipenseriformes) during the period of adaptation and feeding in the Taganrog Bay // Scientific and technical bulletin of the laboratory of ichthyology INENKO. No. 21. St. Petersburg. P. 5–25. (In Russ.).

22. Korobochkina Z. S. 1964. Development and current state of the sturgeon fishery in the Sea of Azov // Trudy VNIRO. V. 54. P. 175–202. (In Russ.).

23. Kostyuchenko V.A. 1955. Biology and state of the sturgeon fishery in the Sea of Azov before regulation of river flow // Trudy VNIRO. V. 31. Iss. 2. P. 174–187. (In Russ.).

24. Krayushkina L. S. 1967. Development of euryhaline in the early stages of ontogenesis in sturgeon of various species and ecological forms // Trudy TsNIORKh. V. 1. P. 181. (In Russ.).

25. Luzhnyak V. A., Korneev A. A. 2006. Modern ichthyofauna of the Lower Don basin in conditions of anthropogenic transformation of runoff // Journal of Ichthyology. V. 46. No. 4. P. 503–511. (In Russ.).

26. Makarov E. V. 1964 a. Reproduction of Azov sturgeons and the current state of their stock // Trudy VNIRO. V. 54. Coll. 2. P. 203–210. (In Russ.).

27. Makarov E. V. 1964 b Assessment of the survival of sturgeon fry raised by Don fish hatcheries // Trudy VNIRO. V. 56. Coll. 3. P. 141–170. (In Russ.).

28. Makarov E. V. 1970 a. Towards an assessment of the natural mortality of Azov sturgeons // Trudy TsNIORKh. V. 2. P. 90–94. (In Russ.).

29. Makarov E.V. 1970 b. On the structure of the spawning population of Azov sturgeons // Trudy TsNIORKh. V. 2. P. 86–90. (In Russ.).

30. Makarov E.V. 1970 c. Dynamics and structure of the Azov sturgeon herd. Ph.D. abstr. in biology. sci. Moscow: VNIRO. 32 p. (In Russ.).

31. Makarov E. V. 1970 d. Assessment of the dynamics and structure of the Azov sturgeon herd // Trudy VNIRO. V. 71 P. 96–155. (In Russ.).

32. Makarov E.V. 1970 e. New data on the biology of Azov sturgeons // Proc. 3rd scient. Conf. of the Rostov State University. Rostovon-Don. P. 37–38. (In Russ.).

33. Makarov E. V., Rekov Yu.I., Chikhachev A. S., Tsvetnenko Yu.B. 1986. Participation of hatchery producers in the formation of the spawning population of Russian sturgeon // Fisheries. No. 9. P. 34–36. (In Russ.).

34. Makarov E. V., Rekov Yu.I. 1997. Azov sturgeons: present and prospects // Abstr. reports of the I Congr. of Ichthyologists of Russia [Astrakhan, September 1997]. Moscow: VNIRO Publish. P. 82. (In Russ.).

35. Makarov E. V., Balandina L. G., Kornienko G. G., Rekov Yu.I. 1998. Ways of development of sturgeon farming in the Azov Sea basin // Main problems of fisheries and protection of fishery reservoirs of the Azov-Black Sea basin. Rostov-on-Don: AzNIIRKH Publish. P. 192–207. (In Russ.).

36. Makarov E.V., Gribanova S.E. 1999. Ways to increase the efficiency of natural reproduction of sturgeon in conditions of regulated river flow // Problems of geography and ecology. Rostov-onDon: RSU. P. 101–112. (In Russ.).

37. Makarov E. V., Tikhonova S. V. 1968. On sexual maturation of Azov sturgeons // Fisheries. No. 5. P. 9–11. (In Russ.).

38. Makarov E. V., Rekov Yu.I. 2000. Current state of sturgeon populations in the Sea of Azov // Sturgeon at the turn of the 21st century: Abstracts of reports international conf., Astrakhan, September 11–15, 2000. Astrakhan: KaspNIRKh. P. 9–10. (In Russ.).

39. Milshtein V.V. 1971. A centennial anniversary of sturgeon farming // Trudy TsNIORKh. V. 3. P. 5–13. (In Russ.).

40. Musatova G. N. 1973. Sturgeon fish of the Kuban River and their reproduction. Krasnodar: Book Publishing House. 112 p. (In Russ.).

41. Muge N. S., Barmintseva A. E. 2014. Methodology for genotyping spawners and juveniles of sturgeon fish species for the purpose of genetic monitoring of artificial reproduction // Actual status and conservation of natural population of sturgeon fish Acipenseridae. Olsztyn. P. 159–165. (In Russ.).

42. Nedoshivin A. Ya. 1926. Current state of Azov fishery // Trudy AzovBlack Sea Scientific and Fishing Expedition. Kerch. V. 1. P. 65–145. (In Russ.).

43. Nedoshivin A. Ya. 1928. Materials on the study of Don fisheries // Trudy Azov-Black Sea Scientific and Fishing Expedition. Kerch. V. 4. P. 25–31. (In Russ.).

44. Pogorelov Ya.N. 1912. On the needs of fishing in the Sea of Azov and the Kerch Strait // Trudy 3rd All-Russian Congress of Fisheries and Other Figures on Fisheries and Fish Farming in St. Petersburg in 1910 [Transcript Report]. Iss. 2. SPb. P. 287–297. (In Russ.).

45. Rekov Yu.I. 1996. Formation of the Azov sturgeon fish stock and its commercial use in modern conditions // Proceedings of AzNIIRKH: Main problems of fisheries and protection of fishery reservoirs of the Azov basin. Rostov-on-Don: Polygraph. P. 178–180. (In Russ.).

46. Rekov Yu.I. 1997. Assessment of the spawning population of Azov sturgeon as a basis for predicting the size of their stock and catch // Proceedings of AzNIIRKH: Main problems of fisheries and protection of water bodies of the Azov-Black Sea basin (1993–1995). Rostov-on-Don: publishing house «Molot». P. 186–195. (In Russ.).

47. Rekov Yu.I. 2000. Changes in Azov sturgeon stocks // Proceedings of AzNIIRKH: Main problems of fisheries and protection of fishery reservoirs of the Azov-Black Sea basin (1998–1999). Rostov-on-Don. P. 84–87. (In Russ.).

48. Rekov Yu.I. 2002. Stocks of Azov sturgeon fish: current state and immediate prospects // Proceedings of AzNIIRKH: Main problems of fisheries and protection of fishery reservoirs of the Azov-Black Sea basin. Moscow: VNIRO Publish. P. 265–272. (In Russ.).

49. Rekov Yu.I., Korneev A. A. 1987. Efficiency of reproduction and replenishment of Azov sturgeon herds // Reproduction of sturgeon stocks in the Caspian and Azov-Black Sea basins. Moscow: VNIRO Publish. P. 94–101. (In Russ.).

50. Rekov Yu.I., Tikhonova G. A., Chepurnaya T. A. 2004. Prospects for restoring the stocks of Azov anadromous sturgeon fish through natural and artificial reproduction // Abstr. of reports intern. scient. conf. «Problems of natural and artificial reproduction of fish in marine and freshwater reservoirs». Rostov-on-Don: Publishing house «TSVVR». P. 128. (In Russ.).

51. Sabodash V.M., Demyanenko K.V. 2005. The state and reproduction of populations of sturgeon fish of the Azov basin in the modern period (review) // Hydrobiological Journal. V. 41. No. 6. pp. 54–73. (In Russ.).

52. Sechin Yu.T. 1986. Guidelines for assessing the number of fish in freshwater bodies. Moscow: VNIIPRH. 50 p. (In Russ.).

53. Sokolov L.I., Tsepkin E.A. 1996. Sturgeon of the Azov-Black Sea and Caspian basins (historical review) // Journal of Ichthyology. V.36. No. 1. pp.15–27. (In Russ.).

54. Smirnov A.N. 1961. The influence of environmental factors on the number of juvenile fish in the Taganrog Bay // Proceedings of the AzNIIRKH in 1960. Rostov-on-Don. pp. 51–53. (In Russ.).

55. Catches of fish and non-fish objects by fishery organizations of the Azov-Black Sea basin [1990–1995]. Statistical collection. 1997. / Yu. I. Zaydiner, L.V. Popova eds. Rostov-on-Don: Molot. 100 p. (In Russ.).

56. Catches of fish and non-fish objects by fishery organizations of the Azov-Black Sea basin (1995–2000). Statistical collection. 2003. / S.E. Gribanova, Yu.I. Zaydiner, E.A. Landar, L.V. Popova, I.N. Filchagin eds. Rostov-on-Don: Everest-M. 90 p. (In Russ.).

57. Catches, stocks and artificial reproduction of aquatic biological resources, production of aquaculture products in the AzovBlack Sea fishery basin (2006–2015). Statistical collection. 2020. / V. N. Belousov ed. Rostov-on-Don: Mini-type. 128 p. (In Russ.).

58. Troitsky S. K. 1973. A story about Azov and Don fish. Rostov-onDon: Rostizdat. 192 p. (In Russ.).

59. Chugunov N.L. 1927. On the impact of the cessation of fishing on sturgeon stocks in the Sea of Azov // Collection papers in honor of prof. N.M. Knipovich. Moscow. P. 271–288. (In Russ.).

60. Chugunov N.L., Chugunova N.I. 1964. Comparative commercial and biological characteristics of sturgeon in the Azov Sea // Trudy VNIRO. V. 52. P. 87–182. (In Russ.).

61. Chusovitina-Krayushkina L.S. 1963. On the early euryhaline of sturgeons and the adaptive function of chloride-secreting cells in their gills // Reports of the USSR AS. V. 151. No. 2. P. 441–442. (In Russ.).

62. Shibaev S. V. 2015. Formal theory of fish life F. I. Baranov and its significance in the development of fisheries science // Trudy VNIRO. V. 157. P. 127–142. (In Russ.).

63. Yanovsky E. G., Demyanenko K. V. 1998. Prospects for the development of sturgeon farming in the Azov Sea basin // Trudy YugNIRO. V. 44. P. 40–44. (In Russ.).

64. Henderson-Arzahola A., King T. L. 2002. Novel microsatellite markers fo Atlantic sturgeon (Acipenser oxyrinchus) population delineation and broodstock management // Mol. Ecol. Notes. V. 2. P. 437–439.

65. Luzhniak V. A. 2022. Population Dynamics of Sturgeon Fish [Acipenseridae, Acipenseriformes] in the Sea of Azov // Journal of Ichthyology. V. 62, No. 7. P. 1404–1418. DOI: 10.1134/S0032945222060157.

66. Mann H. B., Whitney D. R. 1947. On a test of whether one of two random variables is stochastically larger than the other // Annals of Mathematical Statistics. Vol. 18. P. 50–60.

67. Shapiro S. S., Wilk M. B. 1965. An analysis of variance test for normality (complete samples) // Biometrika. Vol. 52. Issue 3/4. P. 591–611.

68. Wilcoxon F. 1945. Individual Comparisons by Ranking Methods. // Biometrics Bulletin 1. P. 80–83.

69. Welsh A., May B. 2006. Development and standartization of disomic microsatellite markers for lake sturgeon genetic studies // J. Appl. Ichthyol. Vol. 22. P. 337–344.

70. Zane L., Patarnello T., Ludwig et al. 2002. Isolation and characterization of microsatellites in the Adriatic sturgeon (Acipenser naccarii) // Mol. Ecol. Notes. Vol. 2. P. 586–588.