| Resumo: |
Age and growth rates of southern anchovy larvae (Engraulis anchoita)were estimated by analysis of daily increments in sagittal otoliths under light microscopy. Samples were collected during 2002 with a bongo net, in the Buenos Aires province, Argentine Sea (SW Atlantic). Otoliths corresponding to 251 larvae (size range 3.5 u 12.2 mm SL)were analyzed. Growth rate estimated as slopes by linear regression of length-age data were 0.50, 0.40, and 0.42 mm/day, and these values corresponded to larvae collected in spring, summer and autumn. Larval growth were significantly distinct between the year seasons (ANCOVA, p<0.01). Recent larval growth expressed as mean growth rates during the last 4 days of the larvae was not correlated with surface temperature. The variation in growth between the three seasons seems to be related to fluctuation in chlorophyll-a concentration and the cycle of primary and secondary production typical of temperate seas.
Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales.
|
