The influence of climate-­oceanological processes on parameters of the state of cod stock in the Barents Sea and adjacent waters

The aim of the paper is to assess the influence of large-­ scale climatic and oceanographic processes on recruitment abundance and mean weight of cod at age 3 in the Barents Sea and adjacent waters.
The material for the study was oceanographic data collected by Polar Branch of VNIRO and other available information on the hydrometeorological conditions of the Barents Sea and adjacent areas as well as data on the biomass of the cod spawning stock, the number of its recruits and the mean weight of fish at age 3 for 1981-2023.
Methods of descriptive statistics as well as comparative, correlation and regression analyses were applied.
Results: The analysis of the conditions for forming the Northeast Arctic (NEA) cod stock in the Barents Sea was carried out. To assess the impact of climate changes on state of the stock, the number of recruits and the mean weight of fish at age 3 were chosen as its parameters. The following climatic factors were used: the winter North Atlantic Oscillation index, the Atlantic water temperature in the Gimsøy and Kola sections, the area-averaged temperature in the Barents Sea (71-79°N 25-55°E) at 100 m depth, and the length index of thermal frontal zones in the Barents Sea. Reliable and adequate regression equations were constructed for the selected stock parameters, including the temperature of Atlantic waters and the length index of frontal zones in the Barents Sea, the biomass of spawning cod stock, and the average number of its recruits at age 3 over the previous two years, which allow forecasts to be made with a lead time of up to one year. Practical significance: The obtained results will allow a better understanding of the processes occurring in the Barents Sea ecosystem, and will be used to assess the impact of climate change and oceanographic conditions on the state of cod stock in the Barents Sea and to forecast its recruitment abundance and mean fish weight at age 3.

1. Alekseev G. V., Glock N. I., Smirnov A. V., Vyazilova A. E. 2016. The influence of the North Atlantic on climate variations in the Barents Sea and their predictability // Meteorology and hydrology. № 8. P. 38-56. (In Russ.).

2. Boytsov V. D., Lebed N. I., Ponomarenko V. P., Ponomarenko I.Ya., Tereshchenko V. V., Tretyak V. L., Shevelev M. S., Yaragina N. A. 1996. The Barents Sea cod (biological and fisheries outline). Murmansk: PINRO Publish. 285 pp. (In Russ.).

3. Gershanovich D. E., Muromtsev A. M. 1983. Oceanological bases of biological productivity of the World Ocean. Leningrad: Gydrometeoizdat. 320 pp. (In Russ.).

4. Gudkovich Z. M., Karklin V. P., Smolyanitsky V. M., Frolov I. E. 2009. On the character and causes of the Earth’s climate changes // Arctic and Antarctic Research. № 81. P. 15-23. (In Russ.).

5. Eliseeva I. I., Yuzbashev M. M. 2004. General theory of statistics. Moscow: Finance and Statistics. 656 pp. (In Russ.).

6. Ivshin V. A., Trofimov A. G., Titov O. V. 2020. Barents Sea thermal frontal zones variability in 1960-2018 // Trudy VNIRO. V. 180. P. 60-71. (In Russ.). DOI: 10.36038/2307‑3497‑2020‑180‑60‑71.

7. Izhevskiy G. K. 1961. Oceanological bases of forming commercial productivity of the seas. Moscow: Pishchepromizdat. 215 pp. (In Russ.).

8. Karsakov A. L., Trofimov A. G., Antsiferov M.Yu., Ivshin V. A., Gubanishchev M. A. 2022. 120 years of oceanographic observations along the Kola Section. Murmansk: N. M. Knipovich PINRO Publish. 145 pp. (In Russ.).

9. Karsakov A. L., Trofimov A. G., Ivshin V. A. 2018. Reconstruction of water temperature data on the Kola Meridian section in 2016-2017 // Trudy VNIRO. V. 173. P. 193-206. (In Russ.)

10. Kasyanov V. A. 2008. Econometrics: educational electronic text publication. Ekaterinburg: UPI. 200 pp. (In Russ.).

11. Kislyakov A. G. 1964. Fluctuations in the hydrological regime of the northern part of the Norwegian Sea and their influence on the formation of generations of the Arctic-­ Norwegian cod stock // Proceedings of the session of the Scientific Council of PINRO on the results of research in 1962-1963. Murmansk. Iss. 3. P. 44-59. (In Russ.)

12. Kovalev Yu.A., Yaragina N. A. 2009. The influence of population density on the growth rate, maturation and productivity of the north-­eastern Arctic cod Gadus morhua morhua L. stock // Voprosy ichthyologii. V. 49. № 1. P. 61-70. (In Russ.).

13. Korosov A. V., Gorbach V. V. 2007. Computer processing of biological data. Petrozavodsk: PetrGU. 76 pp. (In Russ.).

14. Lis N. A., Egorova E. S. 2022. Climatic variability of the ice extent of the Barents Sea and its individual areas // Arctic and Antarctic Research. V. 68. № 3. P. 234-247. 10.30758/0555-2648-2022-68-3-234-247. (In Russ.).

15. Maslov N. A. 1944. Demersal fishes of the Barents Sea and their fishing // Trudy PINRO. V. 8. P. 3-186. (In Russ.).

16. Ozhigin V. K., Tretiak V. L., Yaragina N. A., Ivshin V. A. 1995. Dependence of the growth of arctic-­Norwegian cod Gadus morhua morhua on the conditions of feeding capelin Mallotus villosus villosus and water temperature // Voprosy ichthyologii. V. 35, № 3. P. 334-342. (In Russ.).

17. Ozhigin V. K., Tretyak V. L., Yaragina N. A., Ivshin V. A. 1999. The Barents Sea oceanographic conditions and their impact on the survival and development of juvenile Northeast Arctic cod. Murmansk: PINRO Publish. 88 p. (In Russ.).

18. Sentyabov E. V., Trofimov A . G. 2024. Dynamics of hydrometeorological conditions in the North Atlantic and West Arctic in the age of global climate changes// Trudy VNIRO. Vol. 196. P. 179-192. DOI: 10.36038/2307‑3497‑2024‑196‑179‑192. (In Russ.)..

19. Tereshchenko V. V. 1980. Features of hydrometeorological conditions of drift of eggs and larvae of Lofoten cod // Physicochemical conditions of formation of biological productivity of the Barents Sea. Apatity. P. 34-40. (In Russ.).

20. Timofeeva A. B., Yulin A. V., Ivanov V. V., Sharatunova M. V., Pavlova E. A. 2024. Ice cover of the Russian Arctic seas along the Northern Sea Route in the modern climatic period // Arctica: ecologia i economika. Vol. 14. No/1 (53). P. 135-146. DOI: 10.25283/2223‑4594‑2024‑1‑135‑146. (In Russ).

21. Timokhov L. A., Vyazigina N. A., Mironov E. U., Yulin A. V. 2019. Climatic changes of seasonal and inter-­ annual variability of the ice cover of the Greenland and Barents Seas // Arctic and Antarctic Research. V. 65. № 2. P. 148-168. DOI: 10.30758/0555‑2648‑2019‑65‑2‑148‑168. (In Russ.).

22. Trofimov A. G. 2021. The current trends in oceanographic conditions of the Barents Sea // Trudy VNIRO. V. 186. P. 101-118. (In Russ.). https://doi.org/10.36038/2307-3497-2021-186-101-118.

23. Trofimov A. G., Karsakov A. L., Ivshin V. A. 2018. Climate changes in the Barents Sea over the last half century // Trudy VNIRO. V. 173. P. 79-91. DOI: 10.36038/2307‑3497‑2018‑173‑79‑91. (In Russ.).

24. Trofimov A. G., Yaragina N. A., Ivshin V. A., Kovalev Yu.A., Antsiferov M.Yu., Sentyabov E. V. 2023. Cod distribution in the Barents Sea under climate changes // Trudy VNIRO. V. 192. P. 68-84. DOI: 10.36038/2307‑3497‑2023‑192‑68‑84. (In Russ.).

25. Shevchenko A. V. 2000. Oceanological conditions for forming commercial productivity in the seas of the North European basin. Murmansk: PINRO Publish. 100 pp. (In Russ.).

26. Bogstad B., Dingsør G. E., Ingvaldsen R. B., Gjøsæter H. 2013. Changes in the relations between oceanographic conditions and recruitment of cod, haddock and herring in the Barents Sea // Marine Biology Research. V. 9. P. 895-907. DOI: 10.1080/17451000.2013.775451.

27. Bogstad B., Yaragina N., Nash R. 2016. The early life-history dynamics of Northeast Arctic cod: levels of natural mortality and abundance during the first three years of life // Canadian Journal of Fisheries and Aquatic Sciences. V. 73, No. 2. P. 246-256. DOI: 10.1139/cjfas‑2015‑0093.

28. Boitsov V. D., Karsakov A. L., Trofimov A. G. 2012. Atlantic water temperature and climate in the Barents Sea, 2000-2009 // ICES Journal of Marine Science. V. 69. № 5. P. 833-840. DOI: 10.1093/icesjms/fss075.

29. Cushing D. H. 1995. Population Production and Regulation in the Sea. A Fisheries Perspective. Cambridge: Cambridge University Press. 354 pp.

30. Dalpadado P., Arrigo K. R., Hjøllo S. S., Rey F., Ingvaldsen R. B., Sperfeld E., van Dijken G. L., Stige L. C., Olsen A., Ottersen G. 2014. Productivity in the Barents Sea – ​ response to recent climate variability // PLoS ONE. V. 9, № 5. Art. e95273. DOI: 10.1371/journal.pone.0095273.

31. Dementyeva T. F., Mankevich E. M., 1965. Changes in the growth rate of the Barents Sea cod as affected by environmental factors // ICNAF. Spec. Publ. No. 6. Р. 571-577.

32. Folkvord A. 2005. Comparison of size-at-age of larval Atlantic cod (Gadus morhua) from different populations based on sizeand temperature-­ dependent growth models // Canadian Journal of Fisheries and Aquatic Sciences. V. 62. P. 1037-1052. DOI: 10.1139/F05‑008.

33. González-­Pola C., Larsen K. M.H., Fratantoni P., Beszczynska-­ Möller A. (Eds.) 2023. ICES Report on Ocean Climate 2021 // ICES Cooperative Research Report. V. 358. 123 pp. DOI: 10.17895/ices.pub.24755574.

34. Houde E. D. 2008. Emerging from Hjort’s Shadow // Journal of Northwest Atlantic Fishery Science. V. 41. P. 53-70. DOI: 10.2960/J.v41.m634.

35. Jakobsen T., Ozhigin V. K. (Eds.) 2011. The Barents Sea: ecosystem, resources, management. Half a century of Russian-­Norwegian cooperation. Trondheim: Tapir Academic Press. 825 pp.

36. Langangen Ø., Stige L., Yaragina N., Vikebø N., Bogstad B., Gusdal Y. 2014. Egg mortality of Northeast Arctic cod (Gadus morhua) and haddock (Melanogrammus aeglefinus). ICES Journal of Marine Science. V. 71. Iss. 5. P. 1129-1136. DOI: 10.1093/icesjms/fst007.

37. Little A. G., Loughland I., Seebacher F. 2021. What do warming waters mean for fish physiology and fisheries? // Journal of Fish Biology. No. 98. P. 1493. DOI: 10.1111/jfb.14803.

38. Mohamed B., Nilsen F., Skogseth R. 2022. Interannual and decadal variability of sea surface temperature and sea ice concentration in the Barents Sea // Remote Sensing. V. 14. Iss. 17. Art. 4413. DOI: 10.3390/rs14174413.

39. Morley J. W., Selden R. L., Latour R. J., Frölicher T. L., Seagraves R. J., Pinsky M. L. 2018. Projecting shifts in thermal habitat for 686 species on the North American continental shelf // PLoS One. V. 13. Iss. 5. Art. e0196127. DOI: 10.1371/journal.pone.0196127.

40. Nilssen E. M., Pedersen T., Hopkins C. C.E., Thyholdt K., Pope J. G. 1994. Recruitment variability and growth of Northeast Arctic cod: influence of physical environment, demography, and predator – ​ prey energetics // ICES marine Science Symposia. V. 198. P. 449-470.

41. Opdal A. F., Vikebø F. B., Fiksen O. 2011. Parental migration, climate and thermal exposure of larvae: spawning in southern regions gives Northeast Arctic cod a warm start // Marine Ecology Progress Series, 439: 255-262.

42. Ottersen G., Hjermann D., Stenseth N. C. 2006. Changes in spawning stock structure strengthens the link between climate and recruitment in a heavily fished cod stock // Fisheries Oceanography. V. 15. P. 230-243. DOI: 10.1111/j.1365‑2419.2006.00404.x.

43. Ottersen G., Loeng H. 2000. Covariability in early growth and yearclass strength of Barents Sea cod, haddock and herring: the environmental link // ICES Journal of Marine Science. V. 57. P. 339-348. DOI: 10.1006/jmsc.1999.0529.

44. Poloczanska E. S., Brown C. J., Sydeman W. J. 2023. Global imprint of climate change on marine life // Nature Climate Change. V. 3. P. 919-925. DOI: 10.1038/nclimate1958.

45. Stige L. C., Ottersen G., Dalpadado P., Chan K-S., Hjermann D., Lajus D., Yaragina N., Stenseth N. 2010. Direct and indirect climate forcing in a multi-­ species marine system. Proc. of the Royal Society B // Biological Sciences. V. 277. P. 3411-3420. DOI: 10.1006/jmsc.1999.0529.

46. Sætersdal, G., Loeng, H. 1987. Ecological adaption of reproduction in Northeast Arctic Cod. Fisheries Research, 5: 253-270.