The trophic transfer of total mercury (THg) and its bioaccumulation from prey species to the predator fish Trichiurus lepturus was analysed in coastal waters of southeastern Brazil to evaluate the trace element dynamic in this predator-prey system. The isotopic (δ13C and δ15N) relation between this predator and its prey allowed inferences on prey assimilation and predator feeding habits. The TH...

We used stable carbon (δ13C) and nitrogen (δ15N) isotope analysis to investigate the trophic ecology of 8 small cetacean species of the southwestern South Atlantic Ocean: 6 delphinids (Grampus griseus, Lagenorhynchus cruciger, L. australis, Lissodelphis peronii, Pseudorca crassidens, and Cephalorhynchus commersonii ) and 2 phocoenids (Phocoena dioptrica and P. spinipinnis). We also analyzed sam...

Historically Saccharina spp. beds occurred along the west coast of Hokkaido, an oligotrophic area, and were commercially exploited. Currently extensive commercial Saccharina spp. beds do not form due to nutrient limitations. Here, we postulate that nutrients assimilated by paleo-Saccharina spp. beds may have been derived from spawning herrings (Clupea pallasii) acting as organisms that formed a...

Feeding ecology and geographic location are 2 major factors influencing animal stable isotope signatures, but their relative contributions are poorly understood, which limits the usefulness of stable isotope analysis in the study of animal ecology. To improve our knowledge of the main sources of isotopic variability at sea, we determined δ15N and δ13C signatures in the first primary feather of ...

Organochlorine contaminants (OCs) and stable isotopes of carbon (δ13C) and nitrogen (δ15N) were determined in 7 benthic and 7 pelagic marine invertebrate species from the North American Arctic to identify factors influencing OC concentrations. Values of δ13C separated benthic (enriched in 13C) from pelagic species and δ15N values gave a logical approximation of trophic level (TL). With few exce...

In Central Brazil, plateaus, the most common geomorphologic form, have been undergoing intense conversion from native vegetation to pasture and agriculture in recent decades. We used carbon stable isotope ratios (δ13C) nitrogen (δ15N) assess possible changes soil organic matter dynamics under such land use modifications. This study aimed evaluate differences δ13C δ15N C N stocks between agricul...

Patterns in foliar nitrogen (N) stable isotope ratios (δ15N) have been shown to reveal trends terrestrial N cycles, including the identification of ecosystems where deficiencies limit forest ecosystem productivity. However, there is a gap our understanding within-species variation and species-level response environmental gradients or management. Our objective examine relationship between site i...

Understanding species linkages and energy transfer is a basic goal underlying any attempt at ecosystem analysis. Although the first food-web studies were based on gut contents of captured specimens, the assessment of stable isotopes, mainly δ13C and δ15N, has become a standard methodology for wide-range analyses in the last 30 years. Stable isotopes provide information on the trophic level of s...

To describe temporal dynamics of stable isotope ratios in fishes, we developed a bioenergetics-based model that links isotope ratios to growth, as influenced by fish size, temperature, diet, and prey quality. The model includes error terms for isotope ratios, diet proportions, and fractionation. The model accurately predicted temporal δ15N dynamics of lake trout (Salvelinus namaycush) in a diet...

Earthworms often constitute an important component of agricultural foodwebs. As such, knowledge of their feeding preferences is relevant to the sustainable management of carbon and nutrient cycling in agroecosystems. We used natural abundances of stable isotopes (δ13C and δ15N) in earthworms and two of their putative food sources soil and leaf litter to test hypotheses regarding the feeding pla...