Stable isotopes of carbon (delta13C) and nitrogen (delta15N) were used to describe sources of energy and trophic position for adult Leporinus friderici in the area of the Corumbá Reservoir, Brazil. Samples were collected from April 1999 to March 2000. Spatial variations were not identified in the isotopic composition. The maximum and minimum contribution of C4 plants calculated integrating the ...

Consumer trophic position 2 3 4 5 Im pa ct s on p rim ar y pr od uc tiv ity (p ro po rti on al c ha ng e) -0.5 -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 40% consumption of lower trophic level a r t i c l e i n f o

Trophic dynamics (community composition and feeding relationships) have been identified as important drivers of methylmercury (MeHg) bioaccumulation in lakes, reservoirs, and marine ecosystems. The relative importance of trophic dynamics and geochemical controls on MeHg bioaccumulation in streams, however, remains poorly characterized. MeHg bioaccumulation was evaluated in eight stream ecosyste...

1. Sympatric species are expected to exhibit specialisation that reduces interspecific competition in environments with food resources that exhibit little spatial or temporal variation in availability, while sympatric species in more unpredictable environments should exhibit generalised feeding strategies to exploit a wide range of variable resources. 2. We combined stable isotopes and quantita...

Abstract The trophic position (TP) of fishes determines their importance in terms energy flows within food webs. However, accurate estimations TP are often prevented because the difficulties tracing all sources. This is particularly challenging for omnivorous fishes, such as those from Order Stomiiformes. In this study, we applied recent developments stable isotope analysis amino acids to untan...