Spatial distribution of eggs and larvae of Engraulis anchoita (Hubbs & Marini, 1935) in the southern brazilian shelf

Abstract

This paper describes the horizontal distribution patterns of eggs and larvae of the anchovy, Engraulis anchoita, at two distinct oceanographic regions in the Southern Brazilian Shelf (SBS).  Santa Marta Cape (SMC; 28°30’) is characterized by upwelling, while Albardao (33o) is influenced by Plata Plume Waters (PPW) and the Subtropical Shelf Front (SSF). Ichthyoplankton was sampled during winter 2005 and summer 2007 in SMC and Albardao during darkness and daytime with a Multinet. Three 330μm mesh-nets results were combined to express the horizontal distribution of anchovy early stages. Maps of salinity, temperature, fish eggs and larvae were made to evaluate spatial distributional patterns. Temperature-Salinity-Icthyoplankton (TSI) diagrams were used to infer fish larvae distribution with respect to water mass composition. Mean larvae and eggs abundance during winter was greater than summer, and SMC had higher ichthyoplankton abundance than Albardao.  In both seasons the largest concentration of anchovy eggs and larvae were found in coastal areas with low salinity. Eggs and larvae were usually present in cold waters during winter and summer. According TSI diagrams, PPW was found in both regions and was positively associated with ichthyoplankton abundance.