Management of Pacific Cod Fishery Based on the Knowledge of Population Structure: Molecular Genetic Study

Pacific cod is one of the most important species for many countries in the North Pacific. Existing fishery management is based mostly on TAC setting on administrative and geographical principles rather than in compliance with the population structure of this species. Currently, there is lack of knowledge of number and boundaries of Pacific cod discrete stocks that makes long-term and sustainable fisheries impossible.

Results of molecular genetic study on population structure of Pacific cod are presented. Samples were collected from five different areas of Okhotsk Sea. Gene of Cyt b and CO1 were used as genetic markers in this study.

Samples from southern and northern Kuril Islands showed significant difference from samples collected in other regions of Okhotsk Sea. The proportion of unique haplotypes increases from south to north, which probably indicates that distribution of Pacific cod also went in that direction. Haplotype net visualizes several main haplotypes distributed in population of Pacific cod and characterizes this population as polymorphic and steady for a long period of time.

Multidisciplinary studies, including molecular genetic analysis can reveal the population structure and patterns of discrete stocks, which will serve to develop adequate and efficient measures to make Pacific cod fisheries sustainable.