Community structure of euphausids and copepods in the distribution areas of middle-sized pelagic fish larvae off the west coast of Baja California, Mexico

Abstract

The composition of species and the most abundant and frequent zooplanktonic fauna, Copepoda and Euphausiacea, at distributional areas of larvae of three sardine species off the west coast of Baja California collected in five surveys (1986 to 1991) were analyzed. The reproductive areas of the sardines Sardinops sagax, Opisthonema libertate, and Etrumeus teres were characterized by low diversity of euphausiid species and high diversity of copepods. The most abundant euphausiid was Nyctiphanes simplex, and the most abundant copepods were Calanuspacificus, Pleuromamma abdominalis, Acartia danae, and Paracalanus parvus. The geographic distribution of sardine larvae was inshore, an area inhabited by omnivorous euphausiid and copepod species. The community structures of the euphausiids and copepods in the sardine spawning areas were different for each species of sardine.