Biological reference points for North-East Arctic cod and haddock

• Published in: ICES Journal of Marine Science
• Main Author: Jakobsen, Tore
• Format: Text
• Language: English
• Published: Oxford University Press 1992
• Subjects: Articles; Arctic; Tac; Arctic cod
• Online Access: http://icesjms.oxfordjournals.org/cgi/content/short/49/2/155; https://doi.org/10.1093/icesjms/49.2.155

TAC recommendations for North-East Arctic cod have traditionally been based on F max , but F med might be preferable to F max as a biological reference point. However, the current F med estimate of more than twice F max appears high, and there is reason to question the basis for the estimate. Furthermore, the robustness of F med and its related points F tow and F high to changes in the parameters used for their estimation has not been adequately investigated. The effect of the various parameters on the estimates of the biological reference points for North-East Arctic cod and haddock is tested. F 0·1 and F max calculated on a per-recruit basis are strongly dependent on the parameters used to estimate them, especially the natural mortality. Fmcd is generally more robust and the estimates of F t a and F hing are also relatively stable. A crucial factor in the estimation of F med for cod is whether the maturity is density dependent or not. It is suggested that the F med -family of reference points provides a better founded basis for management of these stocks than F 0.1 and F max .