Carbon, nitrogen and sulphur isotopic fractionation in captive juvenile hooded seal (Cystophora cristata): Application for diet analysis

Abstract

These enrichment values were greater than those previously measured in adult seals. This increase may be related to the higher rate of protein synthesis and catabolism in growing animals. This study is the first report on sulphur isotope enrichment values for a marine mammal species.

Contamination levels and habitat use influence Hg accumulation and stable isotope ratios in the European seabass Dicentrarchus labrax

“…Several studies have demonstrated how the detoxifying activity of liver can change during the lifetime of an organism, due to metabolic shifts linked with growth rates (Le Croizier et al, 2020). Younger fast-growing animals have higher metabolic rates, which lead to faster isotopic routing and contaminant accumulation (Pinzone et al, 2017). Therefore, the large δ 202 Hg tissue offset in BS might be due to the fact that these fish are younger than SE, NS, AES and NAS ones.…”

Habitat and resource segregation of two sympatric seals in the North Sea

“…To reach the methodological requirements of the model, the potential food resources were grouped according to stable isotope composition similarity (Group 1: juvenile cod; Group 2: plaice and sole; Group 3: monkfish, European hake, haddock; Group 4: herring; Group 5: sandeel). Fractionation factors of 0.8 ± 0.1‰ and 3.3 ± 0.1‰ obtained from hooded seal red blood cells were applied for δ 13 C and δ 15 N, respectively (Pinzone et al 2017). The model was run using SIAR (Parnell and Jackson 2015) on R version 3.6.0.…”

“…3 -Bi-plot of carbon and nitrogen isotope composition (mean ± SD) of food sources and consumers species (grey seals and harbour seals) sampled along the Scottish coasts. Fractionation factors of 0.8 ± 0.1‰ and 3.3 ± 0.1‰ were applied for δ 13 C and δ 15 N values, respectively (Pinzone et al 2017). COLOR Fig.…”

Lipid extraction has tissue‐dependent effects on isotopic values (δ34S, δ13C, and δ15N) from different marine predators

“…19,20 This expansion is a consequence of the recent improvements in mass spectrometry that have simplified this complex analytical technique allowing it to be performed relatively routinely, reducing both cost and the total amount of sample required for measurement. 19,21 As sulfur has low trophic fractionation between consumers and their diet ($1.0‰), 17,20,22 δ 34 S allows a researcher to identify the contribution of assimilated prey, with sulfur originating from different sources of primary production (benthic vs pelagic, terrestrial vs marine). 11,23 Consequently, δ 34 S has helped reveal complex trophic networks where carbon has failed to identify some of the trophic chain elements 14,24 and provide higher resolution in ecological niche occupancy.…”