Recruitment of Baltic cod and sprat stocks: identification of critical life stages and incorporation of environmental variability into stock-recruitment relationships

Authors

  • Friedrich W. Köster Institute of Marine Sciences
  • Hans-Harald Hinrichsen Institute of Marine Sciences
  • Dietrich Schnack Institute of Marine Sciences
  • Mike A. St. John Institute of Hydrobiologie and Fisheries Science
  • Brian R. Mackenzie Danish Institute for Fisheries Research
  • Jonna Tomkiewicz Institute of Marine Sciences
  • Christian Möllmann Institute of Marine Sciences
  • Gerd Kraus Institute of Marine Sciences
  • Maris Plikshs Latvian Fisheries Research Institute
  • Andrej Makarchouk Latvian Fisheries Research Institute
  • Eeri Aro Finnish Game and Fisheries Research Institute

DOI:

https://doi.org/10.3989/scimar.2003.67s1129

Keywords:

cod, sprat, Baltic, critical life stage, environment, stock-recruitment relationship

Abstract


The recruitment processes of Baltic cod and sprat were analysed and critical periods were identified by addressing the major impact factors on individual early life history stages separately and relating observed abundance data between successive stages. For cod, recruitment appeared to be dependent on egg survival, with low oxygen concentration in dwelling depths and predation by clupeids as the major causes for egg mortality. Surviving egg production and larval abundance were weakly correlated, whereas larval abundance was significantly related to year class strength. This indicated that the period between the late egg and the early larval stage is critical for cod recruitment. A potential variable identified to affect this life stage was prey availability for larvae. For sprat, early and late egg stage production as well as late egg stage production and larval abundance were significantly related. However, year class strength was largely independent of larval abundance. Thus, the period between the late larval and early juvenile stage appeared to be critical for sprat recruitment. Potential variables identified to affect this life stage were ambient temperature and wind stress. Environmental factors showing statistically significant covariance with the survival of one of these critical life stages were incorporated into stock-recruitment models for individual spawning areas separately and for the Central Baltic combined.

Downloads

Download data is not yet available.

Downloads

Published

2003-04-30

How to Cite

1.
Köster FW, Hinrichsen H-H, Schnack D, John MAS, Mackenzie BR, Tomkiewicz J, Möllmann C, Kraus G, Plikshs M, Makarchouk A, Aro E. Recruitment of Baltic cod and sprat stocks: identification of critical life stages and incorporation of environmental variability into stock-recruitment relationships. scimar [Internet]. 2003Apr.30 [cited 2021Jan.22];67(S1):129-54. Available from: http://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/510

Issue

Section

Articles