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

• Published in: Boreal environment research Vol. 19; no. 5-6; p. 379
• Main Authors: Rohtla, M, Vetemaa, M, Svirgsden, R, Taal, I, Saks, L, Kesler, M, Verliin, A, Saat, T
• Format: Journal Article
• Language: English
• Published: Helsinki Finnish Environment Institute 01.01.2014
• ISSN: 1239-6095; 1797-2469

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. Pair-wise 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).