This study is aimed to take a stock assessment of blackthroat seaperch Doederleinia seaperch regarding the fishing effort of large-powered Danish Seine Fishery and Southwest Sea Danish Seine Fishery. For the assessment, the state-space model was implemented and the standardized catch per unit effort (CPUE) of large powered Danish Seine Fishery and Southwest Sea Danish Seine Fishery which is necessary for the model was estimated with generalized linear model (GLM). The model was adequate for stock assessment because its r-square value was 0.99 and root mean square error (RMSE) value was 0.003. According to the model with 95% confidence interval, maximum sustainable yield (MSY) of Blackthroat seaperch is from 2,634 to 6,765 ton and carrying capacity (K) is between 33,180 and 62,820. Also, the catchability coefficient (q) is between 2.14E-06 and 3.95E-06 and intrinsic growth rate (r) is between 0.31 and 0.72.

Maturation and spawning of the Blackthroat seaperch, Doderleinia berycoides were investigated based on the samples captured in Korean waters from January 2008 to December 2009. Gonadosomatic index began to increase in June, and reached maximum between July to September. After spawning it began to decrease from October. Reproductive season was estimated to July-September, with peak in August. Fecundity was proportional to the size of the female, with the clutch size varying from 115,500 eggs in the smallest female (TL〓28.2cm) to 652,000 eggs in the largest (TL〓33.5cm). Size at 50% sexual maturity (TL50), determined from mature females, was 29.6cm. Annual reproductive cycles of this species could be divided into six successive stages; immature stage (October-May), nucleolus stage (June-July), yolk vesicle stage (July-August), vitellogenic stage (June-September), ripe and spent stage (August-October).