Role of bacteria as food for zooplankton in a eutrophic tropical pond (Ivory Coast)

• Main Authors: /Bouvy, Marc, /Arfi, Robert, /Guiral, Daniel, /Pagano, Marc, /Saint-Jean, Lucien
• Format: Text
• Language: English
• Published: 1994
• Subjects: ETANG; BACTERIE; BIOMASSE; ZOOPLANCTON; CARBONE; TAUX D'INGESTION; ROTIFERE; COPEPODE; Copepods; Rotifer
• Online Access: https://www.documentation.ird.fr/hor/fdi:42254

The aim of this study was to determine bacteria could be a substantial source of carbon for zooplankton and whether the grazing pressure of these metazoan filter-feeders could influence the fate of bacterial production. Eight grazing experiments using natural bacteria labelled with 3H thymidine were conducted in a tropical pond (Ivory Coast) during various phases of biological colonization (rotifer-dominated and copepod-dominated phases of the colonization). Higher grazing and clearance rates were observed with rotifers (Brachionus plicatilis and Hexarthra intermedia), while very low values where obtained when the cyclopoid copepod Apocyclops panamensis was dominant. Less than 1% of the bacterial production was harvested when copepods were dominant, while B. plicatilis consumed up to 36% of this production. However, this consumption of bacteria appeared to contribute only to an insignificant proportion of the daily carbon intake (e.g. 0.9. to 7.1% of body carbon for rotifers). The low contribution of bacteria in the nutrition of zooplankton is discussed in terms of their cell size and their relative abundance in the total amount of seston available. (Résumé d'auteur)