An Integrated Approach to Determine the Stock Structure of Spinyhead Croaker Collichthys lucidus (Sciaenidae) in Chinese Coastal Waters

An integrated approach including analyses of different biological traits is a proven and powerful tool used to assess the population structures of fish species, which is vital for fishery stock conservation and management of wild resources. This study evaluates the use of three natural tags (i.e., microsatellites, parasites, and otolith nucleus chemistry) in order to describe the population structure of the spinyhead croaker, Collichthys lucidus, in the coastal waters of China, on evolutionary and ecological time scales. Spinyhead croaker was assigned with 86% accuracy to its regional origin (northern China vs. southern China) using all three natural tags. Accuracy decreased when incorporating only one type of natural tag (genetics: 19-69%; parasites: 30-60%; otolith chemistry: 51-86%) or when assigning the fish to a fine scale (sea areas: 44-64%; sampled estuaries: 19-66%). However, the overall accuracy assignment improved slightly compared with otolith chemistry (estuaries: 55 vs. 51%; sea areas: 66 vs. 64%; regions: 86 vs. 86%). Three natural tags and integrated results show that C. lucidus in Chinese coastal waters can be separated into distinct northern and southern Chinese stocks. Finally, this information should promote the development of effective conservation strategies and integrated fisheries management plans for this commercially important species.

Automated summary

An integrated approach using three natural tags (microsatellites, parasites, otolith nucleus chemistry) proved effective in accurately distinguishing the population structure of spinyhead croaker into distinct northern and southern Chinese stocks. While individual natural tags had lower accuracy in assigning fish, the combination of all three tags showed good population structure differentiation capabilities.