Whitemouth croaker, Micropogonias furnieri, trapped in a freshwater coastal lagoon: a natural comparison of freshwater and marine influences on otolith chemistry

Abstract

Strontium and barium incorporation into otoliths was compared between whitemouth croaker, Micropogonias furnieri, collected from an entrapped freshwater population (Mirim Lagoon) and a normal marine/estuarine population in southern Brazil. Chemical analysis was performed using LA-ICPMS with the objective of validating the effects of marine and freshwater environments on Sr and Ba incorporation as a basis for further investigation of marine and freshwater connectivity of M. furnieri. The freshwater population was dominated by older fish with mean ±SD age of 34±1 y, whereas the coastal samples were dominated by younger fish of 14±7 y. Comparison of strontium and barium incorporation among otolith life-history profiles indicated significantly higher barium and lower strontium for the freshwater population compared to the marine population. Furthermore, comparison of otolith material deposited in the freshwater, estuarine and marine life-history phases demonstrated clear differences among these environments. Mean concentrations of strontium and barium in otoliths of M. furnieri were respectively 710 and 112 μg g -1 for freshwater, 2069 and 16.7 μg g -1 for estuarine, and 2990 and 2.7 μg g -1 for marine life-history phases. Barium concentrations in otoliths from the freshwater population of M. furnieri appeared high relative to other freshwater species. Strontium levels across life-history profiles of marine fish increased with age from 2000 to 2900 μg g -1 , possibly indicating more time spent in marine than estuarine waters with age. In contrast, for the freshwater population, strontium levels decreased during the first year of life approximately to 700 μg g -1 , and remained low and stable thereafter, consistent with the early life-history occurring in an estuarine environment prior to entrapment in Mirim Lagoon. The results confirm the strong and opposite effects of marine and freshwater environments on incorporation of barium and strontium into otoliths, and indicate that the population of M. furnieri in Mirim Lagoon represents an isolated population that does not reproduce and is therefore likely to become extinct.Estrôncio e bário foram determinados em otólitos de corvina Micropogonias furnieri coletados em habitats de água doce (lagoa Mirim) e costeiros no Sul Brasil. As análises foram realizadas utilizando-se LA-ICPMS, com o objetivo de estabelecer assinaturas químicas específicas para os diferentes habitats e avaliar a aplicabilidade da química de otólitos para o estudo de mudanças de habitat na espécie em questão para futuros estudos sobre conectividade de populações. Os animais coletados na lagoa Mirim apresentaram idade média de 34±1 anos, não sendo observados adultos jovens ou juvenis. Foi verificada uma variação significativa nas concentrações de Sr e Ba em otólitos para áreas marinhas e de água doce. Para ambientes marinhos, a idade média foi de 14±7 anos. Os valores médios de Sr e Ba foram estimados, respectivamente, em 710 e 112 μg g -1 para água doce, 2069 e 16,7 μg g -1 para água estuarina e 2990 ...

Biogenic and diagenetic indicators in archaeological and modern otoliths: Potential and limits of high definition synchrotron micro-XRF elemental mapping

“…8 inset) contains an excursion to 78 μmol·g − 1 and a small population above 80 μmol·g −1 . This range of values exceeds typically-observed literature values for fishes from different origins (up to 48 μmol·g −1 , Campana, 1999;Nakai et al, 1999;Morales-Nin et al, 2012b;Albuquerque et al, 2010Albuquerque et al, , 2012, but similarly high concentrations have been reported (up to 137 μmol·g − 1 , Munro et al, 2005;Lin et al, 2015). The distributions for the other two samples are narrower, extending over 14-22 μmol·g −1 in 424, and 27-51 μmol·g −1 in QCD.…”

Migration and brackish environment use of Prochilodus lineatus (Characiformes: Prochilodontidae) inferred by Sr:Ca ratio transects of otolith

“…Similar to Albuquerque et al (2010), Sr:Ca ratio of the otolith edge (last spot of the transect) was compared among sampling sites using Kruskal Wallis test, in order to evaluate whether there is coherence with the capture sites (Uruguay and Paraná Rivers and La Plata Estuary) and the salinity associated with them (a higher Sr:Ca ratio is expected near the estuary). Data were tested for normality and homogeneity of variance using the Shapiro-Wilk and Levene's tests respectively.…”

Spatial environmental variability of natural markers and habitat use ofCathorops spixiiin a neotropical estuary from otolith chemistry

“…Estuaries have physical and chemical gradients, especially salinity and trace elements, which can be used as natural markers of habitat for aquatic organisms (Albuquerque et al ., 2010; Avigliano & Volpedo, 2013; Mohan & Walther, 2015). The exposure of fish to different water masses through ontogenetic development directly influences the incorporation of trace elements into the otolith (Campana, 2014).…”