|Scales of variation in otolith elemental chemistry of juvenile staghorn sculpin (Leptocottus armatus) in three Pacific Northwest estuaries|Miller, J.A. (2007). Scales of variation in otolith elemental chemistry of juvenile staghorn sculpin (Leptocottus armatus) in three Pacific Northwest estuaries. Mar. Biol. (Berl.) 151(2): 483-494. hdl.handle.net/10.1007/s00227-006-0477-z
In: Marine Biology. Springer: Heidelberg; Berlin. ISSN 0025-3162, more
Although distinct otolith elemental signatures are often observed in fish collected from different estuaries, significant differences are also observed among sites within estuaries. Variation at these smaller spatial scales is not well quantified and has the potential to lead to inappropriate interpretations of otolith elemental data. To quantify variation at multiple scales, the otolith elemental composition (Mg:Ca, Mn:Ca, Sr:Ca, Ba:Ca, and Pb:Ca) of juvenile staghorn sculpin (Leptocottus armatus Girard, 1854) collected from five sites within three estuaries, the Columbia River (two sites) and Coos Bay (one site), Oregon, and Humboldt Bay, California (two sites), was examined. Using laser ablation-inductively coupled plasma mass spectrometry, each otolith was sampled at three zones: (1) within the primordium, which represents the egg and early larval periods; (2) at the outer edge, which represents the juvenile period just prior to collection; and (3) midway between the primordial and edge samples, which represents the late larval and early juvenile period. There were significant differences in otolith metal-to-calcium ratios at all scales examined. Using multi-element otolith signatures, fish were classified to estuary and site within estuary with relatively high levels of accuracy (av = 70–90%). The largest differences in metal-to-calcium ratios were observed between sites within estuaries (<5 km apart) and the smallest differences were observed among otolith zones. Variation in otolith chemistry may be used to provide information on probable habitat use by estuarine fish but studies must be carefully designed.