FEEDING PATTERNS IN 5 PREDATORY FISHES OF THE HIGH PARANA RIVER FLOODPLAIN (PR, BRAZIL)

Between March 1992 and February 1993 five piscivorous fish species, Ac estrorhynchus lacustris (Reinhardt, 1874), Hoplias malabaricus (Bloch, 1794), Rhaphiodon vulpinus Agassiz, 1829, Salminus maxillosus, Valenc iennes, 1840 and Plagioscion squamosissimus (Heckel, 1840), of the hig h Parana River floodplain showed a wide total prey spectrum though onl y three to four taxa were dominant in their diet. Shrimp, Macrobrachiu m amazonicum, were also common to the majority of species. Seasonal an d spatial variations occurred throughout the study period probably due the availability of prey species. The main resources shared by the pr edators were also the most abundant in the area, with consumption mark edly focused on prey about 5.0 cm long. Detrended correspondence analy sis was effective in discriminating two groups of predators species th at exploited distinct microhabitats. The predators with the least scor es consumed small characids that inhabit mid-water or the littoral reg ion, whereas those with the largest scores consumed prey associated to the bottom.