Chemical signatures in the otoliths of a coastal marine fish, Menidia menidia, from the northeastern United States: spatial and temporal differences

Abstract

Knowledge of population structure in marine systems is fundamental to effective management and conservation. The geochemical signature of otoliths may provide a promising natural tag for quantifying population structure in marine fishes. However, the spatial scale at which chemical signatures differ among species from different environments and with different life histories is not yet clear. We examined chemical signatures in the otoliths of juvenile Menidia menidia, a ubiquitous nearshore marine species found along the east coast of North America that undergoes offshore winter migration. Specimens were collected from 16 locations in 2003 and from 9 locations in 2004 between New Jersey and Maine. Otolith geochemistry was analyzed using laser ablation inductively coupled plasma-mass spectrometry and isotope ratio mass spectrometry. Juvenile fish showed significant site-specific differences and were assigned to natal sites with 70% (2003) and 77% (2004) average cross-validated classification accuracies based on elemental (Mg, Mn, Sr, Ba, Cu, and Pb relative to Ca) and isotope (δ 13 C, δ 18 O) ratios using quadratic discriminant function analysis. Geochemical signatures showed significant interannual variation, suggesting natural tags are year-class specific. Results suggest enough heterogeneity exists in marine chemical signatures to track movements and determine whether M. menidia return to their natal, nearshore location upon return from winter migration. Because M. menidia show evidence of local adaptation, knowledge of this winter migration will have evolutionary and ecological implications. Geochemical signatures of otoliths will likely serve as a useful tool in species with similar life histories.

Multi-element otolith fingerprints unravel sea−lagoon lifetime migrations of gilthead sea bream Sparus aurata

“…The value of Mg, Mn, and Cu for identification of fish habitat by otolith fingerprints has already been acknowledged (e.g. Swan et al 2006, Clarke et al 2009, Tanner et al 2011, although the exact roles played by physiological effects, bioavailability, and water temperature in defining their final otolith concentrations remain unclear (Tanner et al 2011). In our case, the spatial differences in otolith concentrations observed largely reflect differences in physicochemical conditions and element bioavailability between the 4 habitats, under the combined influence of Rhône River inputs to the marine coastal zone and the Thau and Mauguio lagoons (Accornero et al 2008, Ollivier et al 2011, minor localized pollutions by Cu and Cr in the Salses-Leucate lagoon (IFREMER 2009), and differences in water temperature and salinity between the lagoons and the sea (Cacho et al 1999, IFREMER 2008.…”

“…They are, therefore, natural tags whose structure and chemistry provide a record of the environmental history of individuals throughout their lives (Campana 1999), and can reveal movements of present and ancient fish between different water bodies (e.g. Carpenter et al 2003, Walther & Thorrold 2006, Clarke et al 2009, Tanner et al 2011. Nevertheless, most studies in this field (e.g.…”

Decoding fingerprints: elemental composition of vertebrae correlates to age-related habitat use in two morphologically similar sharks

“…We looked for evidence of periodic movements of adults into nurseries shown by declines in Sr:Ba ratios (indicating time spent in marine/freshwater habitats for bull sharks) and reductions in element:Ca ratios (indicating time spent in offshore/onshore habitats for pig-eye sharks). Inter-specific Sr:Ba net counts per second (cps) ratios were also compared to infer different salinities of environments occupied within an individual's lifetime (McCulloch et al 2005, Clarke et al 2009). We used Glitter's 'quantitation' window to select birth bands and sections in the line scan analysis that might indicate return movements by adults into nursery environments.…”

Changes in otolith microchemistry over a protracted spawning season influence assignment of natal origin

“…On this larger spatial scale, otolith microchemistry is most successful with diadromous species, where freshwater imparts an identifiable chemical signature to otoliths (e.g. Barbee & Swearer 2007, Clarke et al 2009). Successful application of this method in other systems has been challenging because of a lack of consistency in chemical fingerprints resulting in lower classification success and reduced confidence in inferred patterns of population connectivity (e.g.…”