Composition of the zooplankton community, with emphasis in copepods, in Punta Morales, Golfo de Nicoya, Costa Rica

ABSTRACT

The composition of the mesozooplanktonic community was studied in the Punta Morales estuary, Gulf of Nicoya,Pacific coast of Costa Rica,during 1997.Oblique plankton hauls were performed during high and low tide using a 280 µm mesh screen net equipped with a flowmeter.The community was characterized by holoplanktonic and meroplanktonic organisms.For the holoplanktonic community,the main groups were copepods (80%)and chaetognaths (16%).The most abundant species were the copepods Acartia lilljeborgii and Paracalanus parvus.A.lilljeborgii is a typical estuarine species that maintains high populations in estuarine systems.Meroplankton was represented mainly by crustacean larvae (66%),and icthyoplankton (18%).The dominance of crustacean larvae and icthyoplankton is an evidence of the ecological importance of the Punta Morales zone

RESUMEN

Se estudió la composición de la comunidad mezoplanctónica en Punta Morales,Golfo de Nicoya, Pacífico de Costa Rica,en 1997,arrastrando oblicuamente una red de plancton (280 µm,con flujómetro)durante marea alta y baja.La comunidad estuvo caracterizada por la presencia de organismos holo y meroplanctónicos.Los principales grupos holoplanctónicos fueron copépodos (80%)y quetognatos (16%).Las especies más abundantes fueron los copépodos Acartia lilljeborgii y Paracalanus parvus;A. lilljeborgii es una especie estuarina típica que mantiene altas poblaciones en sistemas estuarinos.El meroplancton estuvo representado principalmente por larvas de crustáceos (66%),e ictioplancton (18%).La dominancia de larvas de crustáceos e ictioplancton evidencian la importancia ecológica de la zona de Punta Morales