Diversity in habitat use by the East Asian fourfinger threadfin Eleutheronema rhadinum revealed by otolith Sr:Ca and Ba:Ca profiles

Determining the movement and migration patterns of fish between different environments is crucial for understanding distribution populations ecological mechanisms underlying their spatial dynamics. This study first to employ otolith Sr:Ca Ba:Ca profiles elucidate habitat use by commercially valuable estuarine species Eleutheronema rhadinum . Age 1+ were present in samples from East China Sea South Sea, caught off October December 2019. Characterization both element through a quantitative approach suggested plasticity E. , especially during year. However, profile revealed more distinct pattern compared with profile, suggesting that ratio appropriate life-history reconstruction this species. Most individuals appeared be estuary-dependent, some appearing have entered fresh water short time year life. After winter, tended move into coastal waters, most apparently overwintered marine environment. Knowledge diverse strategies at life stages should incorporated future conservation management efforts.