Unraveling dispersal of a coastal fish species in the juvenile life stage in the Yellow Sea using otolith chemistry

Abstract

Dispersal is a critical process in marine ecology, with profound implications for population conservation and fisheries management. Previous research has predominantly focused on reef-associated species, but studying the dispersal of more mobile fish species in nearshore environments is exceptionally challenging due to the complex coastal hydrography similar to reefs, and therefore dispersal knowledge of some coastal migratory behavior fish remains preliminary. In this study, we investigated the dispersal of a coastal fish species (small yellow croaker Larimichthys polyactis) in its juvenile life stage using otolith elemental fingerprints. We aimed to investigate the dispersal patterns of juveniles with otolith chemistry and identify potential natal sources. Results indicated that (1) significant geographical variations in the otolith elemental signatures can be considered as natural markers for assessing fish dispersal; (2) although small yellow croakers in the juvenile life stage are capable of settlement, a significant proportion of individuals continue subsequent passive dispersal; (3) juveniles may have originated from 2 natal sources in the sampling areas based on the differences in the near-core chemistry fingerprints. Results demonstrate the applicability of otolith chemistry fingerprints as natural tags in coastal waters and suggest that juveniles with the ability to settle will still employ dispersal strategies. This study contributes to research on fish dispersal in the early life stage and has significant implications for the marine fishery management of small yellow croaker.