Abstract

In October (5-26th) and December (17-24th) of2005, zooplankton samples were taken from 40 stations in the Coquimbo bay (29° 21'- 30° 15' S) and the coastal area of Caldera (26° 46'- 27° 08' S) (FIP Project N° 2004-45). All Emerita analoga larvae were taken from the samples and their developmental stages, relative abundances, numerical dominance and frequency of occurrence were determined. The segregated distribution of different larval stages observed in the two sampling periods and locations, and their relationship with the bathymetric distribution of adults on sandy beaches, allowed determining the dispersion of this species. The distribution and abundance of the larvae are related to the spawning possible areas. The early stages were observed predominantly at stations in the coastal area of Coquimbo, while more developed stages were seen in the open ocean. The highest abundances of megalopas were observed in the northern area. In both areas the early stages were most abundant and in Caldera the larvae of this species were less abundant than in Coquimbo. Differences in developmental stage composition between the two sampling seasons were detected. In October the more advanced stages were dominant, while in December a similar trend to the one described for the Coquimbo bay system was observed. Considering the distance from the nearest sandy beaches; zoea 1 and 2 were the most abundant in closer ranges, zoea 3 and 4 showed maximum dispersion from the sandy beaches and zoea 5 and megalopas were again found at shorter distances, demonstrating their return to the sandy beaches in the coastal area.