[Reconstructing habitat history of Larimichthys polyactis in Lüsi coastal waters of Jiangsu Province, China based on otolith microchemistry].

ABSTRACT

An electron probe microanalyzer (EPMA) was applied to analyze the element Sr and Ca microchemistry patterns in otoliths of Larimichthys polyactis in Lüsi coastal waters of Jiangsu Province, China. The results showed that Sr was heterogeneously distributed along the sagittal plane of the otoliths. The highest Sr concentration was normally found in the otolith cores while much lower concentrations were found in the remaining areas. The corresponding Sr/Ca ratios were (7.10 +/- 1.00) and (4.79 +/- 1.01) in the former and latter, respectively, which were significantly differed (P < 0.01), but low Sr/Ca ratios even as low as (3.51 +/- 0.76) were also observed in several fish. Based on the above results of otolith microchemistry, the habitat history of L. polyactis was reconstructed as that high salinity habitats seemed to be required at the stages of hatching and post-hatching development, while the reduced salinity habitats seemed to be preferable for the growth and development at the remaining stages of the life history. Furthermore, several fish in this study had likely even experienced much lower salinity habitats at the early stages.