Dietary–morphological relationships in a fish assemblage of the Bolivian Amazonian floodplain
Abstract:Morphological correlates of diet were examined in 48 species of freshwater fishes from floodplain lakes in the central part of the Mamoré River (Bolivian Amazon). The species were classified, according to the percentage occurrence of seven food items, into eight broad trophic categories: mud feeders, algivores, herbivores, terrestrial invertivores and omnivores, carnivores, zooplanktivores, aquatic invertivores and piscivores. There were significant relationships between the diet and morphology of the fishes even when the effect of taxonomical relatedness between species was eliminated. Relative gut length was the main morphological variable used to order species on a carnivore to mud feeder gradient. Standard length and head and mouth size were the morphological variables most closely associated with prey size. Mud feeder, algivore and piscivore species appeared as the most dietary and morphologically specialized. These results support both the hypotheses that species morphology influences the diet and that morphological similarity is conserved even in comparison with taxonomically unrelated species.
Document Type: Regular Paper
Affiliations: 1: Instituto de Ecología, Universidad Mayor de San Andrés, Bolivia, CP 10077, La Paz, Bolivia 2: Institut de Recherche pour le Développement (IRD), Université Lyon 1, Laboratoire d'Ecologie des Hydrosystèmes Fluviaux, 43, Bd du 11 Novembre 1918, F-69622 Villeurbanne Cedex, France and
Publication date: 2003-05-01