Influence of sexual dimorphism on stable isotopes and trace element concentrations in the greater hooked squid Moroteuthopsis ingens from New Zealand waters

• Published in: Marine Environmental Research
• Main Authors: Lischka, Alexandra, Braid, H., Cherel, Yves, Bolstad, Kathrin, Lacoue-Labarthe, T., Bustamante, Paco
• Other Authors: Auckland University of Technology (AUT), Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), LIttoral ENvironnement et Sociétés (LIENSs), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: Cephalopods; biomonitoring; bioaccumulation; metals; Onychoteuthidae; [SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Antarctic; New Zealand; Antarc*; greater hooked squid
• Online Access: https://hal.science/hal-02546145; https://hal.science/hal-02546145/document; https://hal.science/hal-02546145/file/Lischka%20et%20al%202020%20MER.pdf; https://doi.org/10.1016/j.marenvres.2020.104976

International audience The Chatham Rise, one of the highest offshore-primary production regions in New Zealand waters, hosts a great abundance and diversity of deep-sea cephalopods including the greater hooked squid, Moroteuthopsis ingens. Stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) and trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb, Se, V, and Zn) were assessed in female and male specimens of different size classes (89–563 mm mantle length). Values of δ13C and δ15N were overall higher in females and δ13C was further influenced by size and sex. Both muscular mantle (the largest fraction of the total body mass) and digestive gland (the known main storage organ for Ag, Cd, Cu and Zn in many cephalopods) tissues were analysed. Higher levels of Cd were observed in males than in females. A positive effect was found between size and Hg concentrations, which could be related to the ontogenetic descent of larger specimens into deeper waters, where they are exposed to higher Hg concentrations, and/or dietary shifts toward Hg-enriched prey with increasing size. This study provides trace element data for this abundant and ecologically important species, and further reveals higher trace element concentrations (especially Hg) in M. ingens from the Chatham Rise, compared to specimens from the sub-Antarctic zone.