Strontium isotopes in otoliths of a non-migratory fish (slimy sculpin): Implications for provenance studies

Sean R. Brennan; Diego P. Fernandez; Christian E. Zimmerman; Thure E. Cerling; Randy J. Brown; Matthew J. Wooller

doi:10.1016/j.gca.2014.10.032

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Strontium isotopes in otoliths of a non-migratory fish (slimy sculpin): Implications for provenance studies

Sean R. Brennan·Diego P. Fernandez·Christian E. Zimmerman·Thure E. Cerling·Randy J. Brown·Matthew J. Wooller

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Abstract

Heterogeneity in 87Sr/86Sr ratios of river-dissolved strontium (Sr) across geologically diverse environments provides a useful tool for investigating provenance, connectivity and movement patterns of various organisms and materials. Evaluation of site-specific 87Sr/86Sr temporal variability throughout study regions is a prerequisite for provenance research, but the dynamics driving temporal variability are generally system-dependent and not accurately predictable. We used the time-keeping properties of otoliths from non-migratory slimy sculpin (Cottus cognatus) to evaluate multi-scale 87Sr/86Sr temporal variability of river waters throughout the Nushagak River, a large (34,700 km2) remote watershed in Alaska, USA. Slimy sculpin otoliths incorporated site-specific temporal variation at sub-annual resolution and were able to record on the order of 0.0001 changes in the 87Sr/86Sr ratio. 87Sr/86Sr profiles of slimy sculpin collected in tributaries and main-stem channels of the upper watershed indicated that these regions were temporally stable, whereas the Lower Nushagak River exhibited some spatio-teporal variability. This study illustrates how the behavioral ecology of a non-migratory organism can be used to evaluate sub-annual 87Sr/86Sr temporal variability and has broad implications for provenance studies employing this tracer.

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Geochimica et Cosmochimica Acta Article

Source-reported bounding extent: 58.83364736298675° to 60.78598138475315° latitude; -159.0655517578125° to -153.665771484375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Sean R. Brennan, Diego P. Fernandez, Christian E. Zimmerman, Thure E. Cerling, Randy J. Brown, Matthew J. Wooller. 2015. Strontium isotopes in otoliths of a non-migratory fish (slimy sculpin): Implications for provenance studies. https://doi.org/10.1016/j.gca.2014.10.032

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