Use of otolith microchemistry as an indicator of the habitat of Anchoa tricolor (Spix & Agassiz, 1829) in a subtropical estuary

BARBARA MAICHAK DE CARVALHO; ALEJANDRA VANINA VOLPEDO; ANDRÉ MARTINS VAZ-DOS-SANTOS ; HENRY LOUIS SPACH

LATIN AMERICAN JOURNAL OF AQUATIC RESEARCH

UNIV CATOLICA DE VALPARAISO

Lugar: Valparaíso; Año: 2017 vol. 45 p. 457 - 465

0718-560X

The objective of the present study was to evaluate the use of sagitta otolith microchemistry (Sr:Ca; Ba:Ca ratios) as an indicator of the habitat of Anchoa tricolor between estuary and the adjacent continental shelf. We analyzed 162 specimens of A. tricolor in the Paranaguá Estuarine Complex (Brazil) and data of salinity and rainfall. The biological and environmental data were grouped into sectors (internal, intermediate and external) and periods (early and late wet and dry periods). The concentrations of Ca, Ba and Sr were determined using an ICP-OES. The Sr:Ca ratio indicated the existence of two groups of probably different origins that use the estuary at the same time but occupy different sectors of the estuary. The Ba:Ca ratio did not differ groups of use in the estuary, but rather, revealed low values suggesting that this species does not use freshwater environments. However, this ratio showed a high variation in the wet period, indicating greater availability of barium in the estuarine regions affected by river discharge. Considering our results, it is possible to classify A. tricolor as an estuarine migrant species. Also, Sr:Ca and Ba:Ca ratios can be indicative of habitat in a subtropical estuary .