Comparison of Biological Characteristics of Pacific Cod Gadus microcephalus between the East and Yellow Seas, Korea

Abstract

We investigated regional differences in the growth and maturation rate of Pacific cod in the East and Yellow Seas. Significant regional differences were detected in the von Bertalanffy growth equation and mean length at maturity (L 50 ). Cod in the East Sea grew at a faster rate than those in the Yellow Sea, with females growing faster than males in both populations. Cod of both sexes matured earlier in the Yellow Sea (age of maturity: 2.3 years for males, 2.6 years for females) than in the East Sea (age of maturity: 3.9 years for males, 4 years for females). These regional differences suggest that Pacific cod in the Yellow Sea, which is at the southwestern extremity of global cod distribution and thus likely to be an inhospitable habitat for this species, have adapted to their environment by developing earlier maturation and slower growth than cod in the East Sea or the Korea Strait. These regional differences must be taken into account when setting biological reference points for management of the Pacific cod fishery in Korean waters.

Genetic structure and dispersal in peripheral populations of a marine fish (Pacific cod, Gadus macrocephalus) and their importance for adaptation to climate change

“…Sampling was conducted during the spawning season from December to March. Maturity stage was estimated by comparing each sample’s total length to sex‐specific 50% length‐at‐maturity estimates from the East and Yellow Seas (Lee et al, 2016), and calculating the gonadosomatic index (100 × gonad/total weight) when weight data were available. Immature individuals were flagged but retained in our analysis (Table 1).…”