Browsing by Autor "Edward D. Burress"

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    First report of four characiform fishes (Ostariophysi: Characiformes) for Uruguay
    (Pensoft Publishers, 2013) Wilson S. Serra; Matías Zarucki; Alejandro Duarte; Edward D. Burress; Franco Teixeira de Mello; Ivan González‐Bergonzoni; Marcelo Loureiro
    In this article the authors present the first report of four characiform fish species for Uruguay, extending their current distribution to the middle and lower Uruguay River basin: Astyanax saguazu Casciotta, Almirón and Azpelicueta, 2003; Hypobrycon poi Almirón, Casciotta, Azpelicueta and Cione, 2001; Leporinus amae Gody, 1980; Cyphocharax saladensis (Meinken, 1933). These species were previously recorded from either the upper Uruguay River, Patos-Merín lagoon system or Paraná River. Color pattern in life for A. saguazu and H. poi are described for the first time.
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    Species‐specific ontogenetic diet shifts among <scp>Neotropical</scp><i>Crenicichla</i>: using stable isotopes and tissue stoichiometry
    (Wiley, 2013) Edward D. Burress; Ana Maria Ribeiro de Castro Duarte; Wilson S. Serra; Michael M. Gangloff; Lynn Siefferman
    Ontogenetic diet shifts were compared among five sympatric pike cichlids Crenicichla in a subtropical South American stream using stable C and N isotopes and tissue stoichiometry (C:N). Within species, stable N isotopes were positively related to body size while C:N showed negative relationships. Stable C isotopes, however, were not related to body size in any species. By modelling the switch to piscivory using gut content-isotope-body size relationships, diet shifts were shown to be species-specific with regard to both rate and degree of piscivory. Compared to other piscivorous lineages, Crenicichla appear to be unusually small-bodied (based on maximum body size). Because of their diversity, abundance and dynamic size-structured functional roles, Crenicichla may exert broad and complex predation pressures on the aquatic community.