Distribution of Penaeid Shrimp Larvae and Postlarvae in the Upper Gulf of California

Abstract

This study describes the distribution pattern of penaeid shrimp larvae and postlarvae in the Upper Gulf of California (UGC) to confirm the trajectories of early stage penaeid shrimp seeking nursery areas, as described by mathematical models. A research cruise was used to sample the total area of the UGC during the major spawning season. Shrimp in various larval stages were concentrated off the Sonora coast (mainland coast) of the UGC, and individuals in postlarvae stage continue this route to the nursery area in the Colorado River delta. Larvae are not advected to nursery areas by residual currents as previously thought. Larvae remain near the mainland coast until they have the motile capability to actively search for a favourable habitat. Este estudio describe el patron de distribucion de las larvas y postlarvas de camarones peneidos en el Alto Golfo de California (AGC). Lo anterior con el proposito de confirmar las trayectorias que siguen los estadios tempranos de los camarones peneidos para alcanzar las areas de crianza que fueron previamente reportadas por modelos numericos. Se llevo a cabo un crucero de investigacion para muestrear toda el area del AGC. Durante la temporada de desove mas importante. Los diferentes estadios larvales se concentraron en la costa de Sonora (costa continental). Los estadios larvales continuaron por esa ruta hacia el area de crianza localizada en el delta del Rio Colorado. La corriente residual no es la que transporta a las larvas de camaron a su area de crianza como se habia pensado previamente. Las larvas se mantienen cerca de la costa continental del Alto Golfo hasta que tienen capacidad natatoria para encontrar el habitat favorable.