Trophic preferences and bioecology of Pimelodus sp. “Gúnguma” in the middle basin of the Atrato River, Colombia

Abstract

Objective: To analyze trophic aspects, condition status and condition factor K of the Gúnguma (Pimelodus sp.), we carried out collections in the El Tigre swamp (middle basin of the Atrato River, Colombia). Methodology: Between January and June 2010. Habits were determined food through the relative importance index (IIR) and the coefficient of emptiness, which allowed to verify that this species is omnivorous, with preferences to wards macroinvertebrates, accompanied by plant elements. In this same sense, it was determined that May (34%) and June (34%) were the months with the highest number of empty stomachs, this product of the rains that increase the flow of the swamp and the food of the species is dispersed. Length-weight relationships by species were analyzed using linear regression, calculating the values of a and b from the equation W = aLb. Results: The condition factor registered an average of 0.94 (±1.31), where its values ranged between 0.82 (±1.36) and 1.06 (±1.18), which shows the good physiological state in which the species is found. The length-weight relationship registered an average of 1.18 (±0.17), with a strong degree of association between the variables (r=0.99), presenting an allometric growth for the Gúnguma, indicating that the increase in height is faster than the increase in weight. Conclusions: Pimelodus sp. is a species of omnivorous habits with preference in its diet for macroinvertebrate remains, seeds and fruits.