Environmental factors affecting anchovy reproductive potential in the southern coastal waters of Korea

Abstract

We examined the reproductive potential of the anchovy, Engraulis japonicus, based on the data of adult maturation and the feeding environment in the southeastern and southwestern coastal waters of the Korean Peninsula during early spawning season of 2006-2009. Salinity and Chlorophyll a (Chl-a) concentration displayed significant yearly and regional differences (p<0.01 for both). The mean densities of the copepods, gonad somatic index (GSI), and condition factor (CF) of the anchovy were higher in 2008 than in 2006, 2007, and 2009 (p<0.001). GSI and CF were higher in the southwestern area than in the southeastern area (p<0.001). Half of the females were mature at 8.6 cm FL in 2008 and 9.3-9.5 cm FL in 2006, 2007, and 2009. Positive relationships (p<0.05) between CF and the copepods density in the same month and CF and GSI with a one-month time lag revealed that anchovy reproduction potential in the southern coastal waters of Korea is related to changes in the feeding environment and through their energy reserves, showing evidence of the bottom-up effects. © 2013 Copyright Korean Society for Integrative Biology.