日本海西部海域産アカムツの資源動態

Stock-recruitment relationship of red sea bass Doederleinia berycoides from the western Sea of Japan

Creators Imai Chifumi

Creators Michine Atsushi

Creators Murayama Tatsurou

The western Sea of Japan stock of red sea bass Doederleinia berycoides was analysed for stock-recruitment relationship using virtual population analysis. The biomass of spawning females increased from 230t in 1996 to 620t in 2007, and varied around 500t thereafter. Recruitment (number of age 1 fish of next year) ranged from 3.2 million in 1994 to 27.5 million in 2013. The strong year-classes were observed three years interval after 1998. The Ricker type stock-recruitment model, R^^^=36.2Pe^{-0.000160P}, was derived. An index of year class strength was evaluated from the relative distance from the Ricker curve, RR=(R-R^^^)/R^^^). The RR of 1998 year class was maximum of 1.63, and of 1994 was minimum of -0.65. Significant positive correlations were observed between RR and sea water temperature at west of the Oki Islands in August. It was considered that recruitment success of red sea bass may be enhanced by high temperatures in summer spawning season.

[ISSN]0370-9361