Espinoza P. auteur aut IRD Lorrain Anne auteur aut IRD Ménard Frédéric auteur aut IRD Cherel Y. auteur aut IRD Tremblay-Boyer L. auteur aut IRD Arguelles J. auteur aut IRD Tafur R. auteur aut IRD Bertrand Sophie auteur aut IRD Tremblay Yann auteur aut IRD Ayon P. auteur aut IRD Munaron Jean-Marie auteur aut IRD Richard P. auteur aut IRD Bertrand Arnaud auteur aut IRD text journalArticle eng text/pdf born digital access The northern Humboldt Current system (NHCS) is the most productive eastern boundary upwelling system (EBUS) in terms of fish productivity despite having a moderate primary production compared with other EBUS. To understand this apparent paradox, an updated vision of the trophic relationships in the NHCS is required. Using delta C-13 and delta N-15 as a proxy of foraging habitat and trophic position, respectively, we focused on thirteen relevant taxonomic groups from zooplankton to air-breathing top predators collected off Peru from 2008 to 2011. Estimates of trophic position (TP) for the anchoveta Engraulis ringens were high (3.4-3.7), in accordance with previous studies showing zooplankton as a major contributor to anchoveta diet and challenging the often-cited short food chain hypothesis for this ecosystem. The squat lobster, Pleuroncodes monodon, a little studied consumer had similar delta N-15 values that of anchoveta, and thus similar trophic position. However, their differing delta C-13 values indicate that their foraging habitat do not fully overlap, which could alleviate potential competition between these species. Given the current high biomass of squat lobsters in the ecosystem, we encourage that future research focus on this species and its role in the diet of top predators. The present study provides first estimates of the relative TP of important taxonomic groups in the NHCS, which are needed to revisit anchoveta-centred ecosystem models for this region. Further work using amino acid compound specific stable isotope analyses is now required to confirm these TP estimates. specialized PEROU PACIFIQUE HUMBOLDT COURANT 036 040 164 4 art. 86 [15 p.] 2017 0025-3162 https://www.documentation.ird.fr/hor/fdi:010069458 10.1007/s00227-017-3119-8 0025-3162 [F B010069458] https://www.documentation.ird.fr/hor/fdi:010069458 https://www.documentation.ird.fr/intranet/publi/2017/04/010069458.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2017-05-09 2023-07-11 fdi:010069458 fre