Spatial and temporal variability of zooplankton populations in Arcachon bay (bay of Biscay) during oyster breeding

Océanographie du Golfe de Gasgogne (Biarritz, 4-6 avril 2000)

Auteur(s) et Affiliation(s)



Description :
Spatial and temporal short-term variations of zooplankton populations were studied during oyster breeding in the most inner part of Arcachon bay. This environment is submitted both to oceanic (bay of Biscay) and continental (Leyre) inputs and its continental marshes are intensively exploited for oyster farming. This study is a first attempt to describe the zooplanktonic environment of oyster larvae. Correspondence analyses showed that the mesozooplankton composition resulted from the mixing of several communities dominated by copepods throughout the study (64.3 ± 3.5% of total abundance). Appendicularians and polychete larvae were the two other dominant taxa (14.8 ± 6.0% and 7.15 ± 3.8%, respectively). Three distinct communities were observed: (i) an autochtonous community with essentially Acartia discaudata, Acartia grani and Isias clavipes; (ii) an inner community characterized by Acartia bifilosa and Acartia tonsa; (iii) a neritic assemblage characterized by Paraca lanus parvus and Penilia avirostris. Spatial and temporal variations of the communities were closely linked to variations of environmental factors (temperature, salinity and hydrology) and particularly to changes in weather conditions. A storm event during mid-August had an effect on the hydrodynamics in the bay with subsequent changes in the zooplankton community structure. This event resulted in a large scattering of holo- and meroplanktonic organisms (and among them bivalve larvae).


Type de document :
Congrès

Source :
Colloque international d'océanographie du Golfe de Gascogne, 7, Biarritz, France, 2000-04-04, Actes de colloques - IFREMER, issn : 0761-3962, 2001, vol. 31, p. 334-339, Références bibliographiques : 5 ref.

Date :
2001

Identifiants :
isbn : 2-84433-054-1

Editeur :
Pays édition : France, Plouzané, Institut français de recherche pour l'exploitation de la mer