Congruence of stock production and assessment areas? An historical perspective on Canada’s iconic Northern cod

نویسندگان

چکیده

Fisheries management requires spatially congruent production and assessment areas. Canada’s Northern cod, initially considered a stock complex distributed from northern Labrador to Grand Bank, had its boundary reduced southern in the early 1970s. Spatial incongruence has resulted spawning biomass (SSB) recruitment (R) between historical recent eras. To investigate temporal changes, four stanzas of SSB R were derived statistical Perron breaks. In stanza 1, 1960s, off coincided with higher than following 1970s onward. SSB-R relationships that include 1960s data do not represent potential more southerly stock. Loglinear models (density-dependent did improve fit) indicated greatest effect, indices climate south-north distribution explained 86% variance. Lack density-dependence suggests long-standing overfishing, making reference points problematic. growth is suggested as an alternative target. Rebuilding cod historic abundance full “portfolio” Bank (a re-managed 2+3KL stock). With contracted range, lower should be anticipated.

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ژورنال

عنوان ژورنال: Canadian Journal of Fisheries and Aquatic Sciences

سال: 2022

ISSN: ['0706-652X', '1205-7533']

DOI: https://doi.org/10.1139/cjfas-2021-0230