Global trophic position comparison of two dominant mesopelagic fish families (Myctophidae, Stomiidae) using amino acid nitrogen isotopic analyses.

ABSTRACT: The δ(15)N values of organisms are commonly used across diverse ecosystems to estimate trophic position and infer trophic connectivity. We undertook a novel cross-basin comparison of trophic position in two ecologically well-characterized and different groups of dominant mid-water fish consumers using amino acid nitrogen isotope compositions. We found that trophic positions estimated from the δ(15)N values of individual amino acids are nearly uniform within both families of these fishes across five global regions despite great variability in bulk tissue δ(15)N values. Regional differences in the δ(15)N values of phenylalanine confirmed that bulk tissue δ(15)N values reflect region-specific water mass biogeochemistry controlling δ(15)N values at the base of the food web. Trophic positions c

SUBMITTER: Choy CA 

PROVIDER: S-EPMC3509156 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature