Using otolith 87Sr:86Sr as a natal chemical tag in the progeny of anadromous Baltic Sea pike (Esox lucius) — a pilot study

摘要

Otolith 87Sr:86Sr were quantified in 54 young-of-the-year pike (Esox lucius) collected from five west-Estonian freshwater sites to investigate the potential use of 87Sr:86Sr as a natural site-specific tag. Significant differences were found among the selected study sites. Pairwise comparisons revealed that only two sites were statistically indistinguishable from one another. Our results stress the need for understanding the migratory biology of the study species if significant early-life movements (e.g. seaward migration) occur. During the chemical analysis, maternally-influenced region (i.e. the core) should also be avoided or its data excluded. Based on our results and data from other studies we suggest that otolith 87Sr:86Sr is a powerful, yet underused marker to study the natal origins of freshwater spawning Baltic Sea fish at local (e.g. between neighbouring rivers) and regional scale (e.g. between drainage basins).