Ontogenetic diet shifts: an additional mechanism for successful invasion of a piranha species in a Neotropical floodplain

Abstract Ontogenetic shifts in food preference reduces intraspecific competition as immature individuals eat different types than adults. This diet plasticity could facilitate species’ ability to successfully invade and establish itself a new environment, even when co-occurring with phylogenetically close species. Here, ontogenetic of non-native piranha species (Serrasalmus marginatus) was tested by analyzing the relationship between its body length carbon nitrogen stable isotope signatures. Carbon not correlated fish length, but positive significant correlation δ15N values found for piranha. Also, adult S. marginatus showed low isotopic niche overlap. The δ15N, trophic overlap adult, indicate that had preference, which may be viewed an additional mechanism underlying successful establishment upper Parana River. Our findings invasive trait facilitates tropical aquatic systems.