Putting the pieces together: Recent growth, nutritional condition, and mortality of Engraulis anchoita larvae in the southwest atlantic

DO SOUTO, M.; BROWN, D.; SEGURA, V.; NEGRI, R.; TEMPERONI, B.; CEPEDA, G.; VIÑAS, M.; CAPITANIO, F.; DIAZ, M.V.

FISHERIES OCEANOGRAPHY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2019 vol. 28 p. 597 - 611

1054-6006

Dynamics of clupeiform fish populations such as anchovy are frequentlyimpacted by environmental variations which can affect the success of thespecies recruitment. Herein, we have analyzed recent otolith growth rate,RNA/DNA nutritional condition index (sRD), and mortality rate ofargentine anchovy larvae Engraulis anchoita from three different nurseryareas in the Southwest Atlantic. We have evaluated the relationshipbetween the environmental variables (abundance of copepod nauplii,temperature, chlorophyll‐a concentration, and abundance of E. anchoitalarvae) and larval endogenous variables (size, weight, age, and otolithradius) to sRD and recent growth rate. Fast larval growth rates wereobserved toward the northern sector of the studied area, characterized byhigher temperature. High values of sRD were associated with highernauplii abundance in the proximity of coastal fronts. The larvae with thelowest growths and lowest minimum values of nutritional conditioncoincided with the area where there was less abundance of nauplii andhigher larval mortality. Larval size and nauplii abundance were positiveexplanatory factors for both recent growth rate and sRD index.Temperature had a positive effect on recent growth rate and a negativeeffect on sRD index. This condition index was poorly explained in termsof model fit in comparison with the growth model. The results hereinprovided could be significant to better understand the recruitment of thespecies, as to determining favorable areas for the growth and survival ofanchovy larvae.