Skip to main content

Effects of salinity on spermatozoa motility, percentage of fertilized eggs and egg development of Baltic cod (Gadus morhua), and implications for cod stock fluctuations in the Baltic

Abstract

Variation in cod stock strength in the Baltic Sea is considered to be dependent on abiotic conditions such as salinity and water oxygen content in the spawning areas (the Baltic deep basins). Spawning cod were caught off northern Gotland, Sweden, from April to June in 1989 and 1990. Our investigation revealed a reduction in spermatozoan motility and a subsequent reduction in the percentage of fertilized eggs in salinities of 10 to 12‰. Normal egg development required a minimum salinity of 11‰. This coincides with the osmolality of the seminal plasma and egg yolk; i.e., the Baltic cod is adapted to hyperosmotic conditions for spawning and is thus totally dependent on periodical inflows of saline water from the North Sea.

This is a preview of subscription content, access via your institution.

Literature cited

  • Davenport, J., Lonning, S., Kjorsvik, E. (1981). Osmotic and structural changes during early development of eggs and larvae of the cod,Gadus morhua. J. Fish biol. 19: 317–331

    Google Scholar 

  • Fletcher, C. R. (1978). Osmotic and ionic regulation in the cod (Gadus morhua). J. comp. Physiol. 124: 149–155

    Google Scholar 

  • Grauman, G. B. (1973). Investigations of factors influencing fluctuations in abundance of Baltic cod. Rapp. P.-v. Réun. Cons. int. Explor. Mer 164: 73–76

    Google Scholar 

  • Hansson, S., Rudstam, L. G. (1990). Eutrophication and Baltic fish community. Ambio 19: 123–125

    Google Scholar 

  • Hohendorf, K. (1968). Zur Schwebfähigkeit pelagischer Fischeier in der Ostsee. Ber. dt. wiss. Kommn Meeresforsch. 19: 181–193

    Google Scholar 

  • Kändler, R. (1944). Untersuchungen über den Ostseedorsch während der Forschungsfahrten mit dem R.F.D. „Poseidon“ in den Jahren 1925–1938. Ber. dt. wiss. Kommn Meeresforsch. (Neue Folge) 11 (2): 137–245

    Google Scholar 

  • Lebedek, W. (1978). Occurrence and distribution of sprat and cod eggs and larvae in the sourthern Baltic in 1977. Int. Counc. Explor. Sea Comm. Meet. (Baltic fish Comm.) J: 15: 1–4

    Google Scholar 

  • Mangor-Jensen, A. (1987). Water balance in developing eggs of the cod Gadus morhua. In: Fish physiology and biochemistry, Vol. 3. Kugler Publications, Amsterdam/Berkeley, p. 17–24

    Google Scholar 

  • Modin, J. (1987). A note on large catches of cod,Gadus morhua, in the Bothnian sea during spring 1987. Int. Counc. Explor. Sea Comm. Meet. (Baltic Fish Comm.) J: 26: 1–4

    Google Scholar 

  • Morisawa, M., Suzuki, K. (1980). Osmolality and potassium ion: their roles in initiation of sperm motility in teleosts. Science, N.Y. 210: 1145–1146

    Google Scholar 

  • Mork, J., Ryman, N., Ståhl, G., Utter, F., Sundnes, G. (1985). Genetic variations in cod (Gadus morhua): little divergence throughout its range. Can. J. Fish. aquat. Sciences 42: 1580–1587

    Google Scholar 

  • Otterlind, G. (1984a). On fluctuations of the Baltic cod stock. Int. Counc. Explor. Sea Comm. Meet. (Baltic Fish Comm.) J: 14: 1–10

    Google Scholar 

  • Otterlind, G. (1984b). Cod migration and transplantation experiments. Int. Counc. Explor. Sea Comm. Meet. (Baltic Fish Comm.) J: 13: 1–21

    Google Scholar 

  • Riis-Vestergaard, J. (1984). Water balance in cod eggs. In: Dahl, E., Danielssen, D. S., Molesness, E., Solemdal, P. (eds.) The propagation of cod,Gadus morhua. Part 1. Flodevigen rapportser, No. 1. Oluf Rasmussen, Skien, p. 87–103

    Google Scholar 

  • Riis-Vestergaard, J. (1987). Physiology of teleost embryos related to environmental challenges. Sarsia 72: 351–358

    Google Scholar 

  • Solemdal, P. (1970). The reproductive adaption of marine teleosts to water of low salinity. Int. Counc. Explor. Sea Comm. Meet. (Demersal Fish Comm.) F: 30: 1–2

    Google Scholar 

  • Stoss, J. (1983). Fish gamete preservation and spermatozoan physiology. In: Hoar, W. S., Randall, D. J., Donaldson, E. M. (eds.) Fish physiology, Vol. IXB. Academic Press, New York, p. 305–350

    Google Scholar 

  • Strodtmann, S. (1918). Weitere Untersuchungen über Ostseefische, III. Ber. wiss. Meeresunters. Abt. Helgoland (Neue Folge) 14: 31–95

    Google Scholar 

  • Westernhagen, H. v. (1970). Erbrutung der von Dorsch (Gadus morhua), Flunder (Pleuronectes flesus), und Scholle (Pleuronectes platessa) unter kombinierten Temperatur- und Salzgehaltsbedingungen. Helgoländer wiss. Meeresunters. 21: 21–102

    Google Scholar 

  • Wieland, K. (1987). Distribution and mortality of cod eggs in the Bornholm Basin (Baltic Sea). Int. Counc. Explor. Sea Comm. Meet. (Baltic Fish Comm.) G: 56: 1–14

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Additional information

Communicated by T. Fenchel, Helsingør

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Westin, L., Nissling, A. Effects of salinity on spermatozoa motility, percentage of fertilized eggs and egg development of Baltic cod (Gadus morhua), and implications for cod stock fluctuations in the Baltic. Mar. Biol. 108, 5–9 (1991). https://doi.org/10.1007/BF01313465

Download citation

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01313465

Keywords

  • Saline Water
  • Spermatozoan Motility
  • Seminal Plasma
  • Subsequent Reduction
  • Abiotic Condition