Analysis of the stomach contents of sabaleta Brycon henni Eigenmann, 1913 in the lower part of the Timbío river, Cauca-Colombia

Abstract

Between the months of June to December 2016 and January to February 2017, a study of the bioecological status of the species Brycon henni in the lower part of the Timbío River was carried out, with the aim of studying their feeding habits in relation to the development and sex of the species. For this purpose, three sampling stations of 100 m. each were defined in the lower part of the Timbío river; fish collection was carried out using methods such as trawl net and the casting in each of the selected stations, with equal sampling intensity per station. Regarding the food content found in the digestive system (esophagus), on average 49% was animal material, especially aquatic insect larvae, 29% was detritus and 21% was animal material such as diatoms, green algae and moss. In general, there are significant differences in resource consumption between developmental stages and seasons (kruskall, p≤0.05), with fry and juveniles consuming less plant material with respect to the adult stage, while females appear to prey on a greater amount of insect larvae. As for the animal resource, the greatest number of organisms found were of the order Diptera (37%), followed by Trichoptera larvae (23%), Coleoptera (13%) and Hemiptera (12%).  There was evidence of a predilection for Trichoptera and Diptera larvae among the smaller organisms, while adults prefer Coleoptera and Hemiptera, especially males. It can be corroborated that, like many of its relatives, the species B. henni is omnivorous with predatory preferences, especially for aquatic insects, varying its consumption depending on the stage of development, the seasons and, to a lesser extent, the sex of the organisms.