Lazzaro Xavier. (1991). Feeding convergence in South American and African zooplanktivorous cichlids Geophagus brasiliensis and Tilapia rendalli. Environmental Biology of Fishes, 31, p. 283-293. ISSN 0378-1909.
Titre du document
Feeding convergence in South American and African zooplanktivorous cichlids Geophagus brasiliensis and Tilapia rendalli
Année de publication
1991
Type de document
Article
Auteurs
Lazzaro Xavier
Source
Environmental Biology of Fishes, 1991,
31, p. 283-293 ISSN 0378-1909
Acara, Geophagus brasiliensis, and red-breasted bream, Tilapia rendalli, are important planktivorous cichlids in Southern Brazilian lakes and reservoirs. In laboratory experiments, I quantified behavior and selectivity of different sizes of these two fish feeding on lake zooplankton. Feeding behavior depended on fish size. Fish <30 mm were visual feeders. Fish 30-50 mm either visually feed or pump-filter fed depending on zooplankton size. Fish >70 mm were pump-filter feeders. Replicate 1 h feeding trials revealed that, as the relative proportions of prey changed during an experiment, acara (30-42 mm, standard lenght) and tilapia (29-42 mm) shifted from visual feeding on large evasive copepods to filter feeding on small cladocerans and rotifers. Electivity and feeding rate increased with prey lenght, but were distinct for similar-sized cladocerans and copepods. Visual/filter-feeding fish had lowest electivities for small and poorly evasive rotifers and cyclopoid nauplii. (D'après résumé d'auteur)
