versión On-line ISSN 0717-6538
SAGRETTI, Luis y BISTONI, María de los Angeles. FEEDING OF ODONTESTHES BONARIENSIS (CUVIER Y VALENCIENNES 1835 1835) (ATHERINIFORMES, ATHERINIDAE) IN THE SALINE LAKE OF MAR CHIQUITA (CORDOBA, ARGENTINA. Gayana (Concepc.) [online]. 2001, vol.65, n.1, pp. 37-42. ISSN 0717-6538. doi: 10.4067/S0717-65382001000100006.
The aim of this work was to study the feeding habits of silverside Odontesthes bonariensis in a habitat characterized by its extension and high salinity. Stomach contents of 258 individuals were analyzed. Seasonal frequency sampling was conducted in the southern coast of Mar Chiquita Lake during 1994-1995. The trophic spectrum was determined, establishing the frequency of occurrence, abundance and volume for each item. The Index of Relative Importance (IRI) was estimated. O. bonariensis behaves as a zoophagous species. The main component of the diet varied according to fish size, showing a marked ichthyophagy in those specimens with more than 200 mm in standard length. O. bonariensis fed almost exclusively on Jenynsia multidentata. Cannibalism occurred only twice. The capture of the latter species decreased in autumn and summer. This could explain the seasonal variation registered in the diet of the silverside (O. bonariensis). The main food item in spring and summer were fish, whereas snails Littoridina parchappe and insects were the most important preys in autumn and winter respectively. Among the insects the most important orders were Diptera and Hemiptera. O. bonariensis in the adult stage can be considered an ichthyophagous species based on its feeding habits in the Mar Chiquita Lake
Palabras clave : Feeding habit; Atherinidae; piscivorous fish; Mar Chiquita.