Abstract
Larimichthys polyactis, a typically oceanodromous species found across the East China, Yellow, and Bohai Seas, is one of the most ecologically and commercially important species in East Asian countries. Moreover, over the past decades, L. polyactis has experienced significant changes in its biological characteristics under long-term intensive fishing pressure, suggesting a need for urgent protection. A robust understanding of connectivity at the spatiotemporal scale is critical for the effective and thorough management of L. polyactis. In the present study, the otolith stable carbon (δ13C) and oxygen (δ18O) isotope ratios of four adult L. polyactis groups (Y-1–4) sampled in the southern Yellow and East China Seas (SYS and ECS) were determined at multiple life stages, including the larval dispersal period (core), overwintering period (A1), and one whole life cycle except the post-spawning period (A2). Dunn’s multiple comparison test showed that there was no difference among the Y-1, Y-2, and Y-3 groups in the otolith core and A1 zones (p > 0.05); the otolith δ13C and δ18O of the Y-4 group were significantly higher than those of the Y-3 group (p