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Integrating ontogenetic shift, growth and mortality to determine a species' ecological role from isotopic signatures.

ABSTRACT: 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 ?13C and ?15N, has become a standard methodology for wide-range analyses in the last 30 years. Stable isotopes provide information on the trophic level of species, food-web length, and origin of organic matter ingested by consumers. In this study, we analyzed the ontogenetic variability of ?13C and ?15N obtained from samples of three Neotropical fish species: silver sardine (Lycengraulis grossidens, n=46), white lambari (Cyanocharax alburnus, n= 26), and the red-tail lambari (Astyanax fasciatus, n=23) in Pinguela Lagoon, southern Brazil. We developed a new metric, called the Weighted Isotopic Signature (? 15N or ? 13C, ‰), that incorporates ontogenetic variability, body growth, and natural mortality into a single number.

SUBMITTER: Fontoura NF

PROVIDER: S-EPMC4440762 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Integrating ontogenetic shift, growth and mortality to determine a species' ecological role from isotopic signatures.

Fontoura Nelson F NF Rodrigues Lúcia R LR Batista Cibele B CB Persch Tanilene S P TS Janowicz Mariola E ME

PloS one 20150521 5

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 species, food-web length, and origin of organic matter ingested by consumers. In this study, we analyzed ...[more]

PMID: 25996777

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Dataset Information

Integrating ontogenetic shift, growth and mortality to determine a species' ecological role from isotopic signatures.

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Integrating ontogenetic shift, growth and mortality to determine a species' ecological role from isotopic signatures.

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