Aspects of trophic ecology of odontocetes from Uruguay

VALDIVIA, MEICA; BERRIEL, VERONICA; VALENZUELA, LUCIANO O; RODRIGUEZ, DIEGO; BERGAMINO, LEANDRO

Viña del Mar

Conferencia; The 11th International Conference on Applications of Stable Isotope Techniques to Ecological Studies; 2018

Marine mammals are generally key species attributed to its predation in almost all trophic levels, therefore changes in their abundance and distribution could affect the structure and function of ecosystems. Along the coast of Uruguay a total of 40 species of marine mammals have been recorded, 32 belong to the order Cetartiodactyla which are in turn divided between the suborders Odontoceti (22 spp) and Mysticeti (10 spp). Despite this, the information on the trophic ecology of these top predators remains scarce in Uruguay. The aim of this work is to evaluate resource partitioning in three species of the suborder Odontoceti occurring in Uruguayan waters: Tursiops truncatus, Pseudorca crassidens and Delphinus delphis. In order to examine trophic relationships and compare isotopic niche space among species, carbon and nitrogen stable isotopes (δ13C and δ15N) in collagen are analyzed. For this propose specimens held in national collections in the coasts of Uruguay between the years 1947 and 2016 were sampled. The knowledge about trophic relationships and the degree of trophic overlap between these predators allows us to understand the mechanisms through which they can coexist, moreover is important for understanding the ecological roles of these animals in the food webs.