title: Trophic ecology of Atlantic Bluefin Tuna (Thunnus thynnus) [corrected] larvae from the Gulf of Mexico and NW Mediterranean spawning grounds: A Comparative Stable Isotope Study.
abstract: The present study uses stable isotopes of nitrogen and carbon (δ15Nandδ13C) as trophic indicators for Atlantic bluefin tuna larvae (BFT) (6-10 mm standard length) in the highly contrasting environmental conditions of the Gulf of Mexico (GOM) and the Balearic Sea (MED). These regions are differentiated by their temperature regime and relative productivity, with the GOM being significantly warmer and more productive. MED BFT larvae showed the highest δ15N signatures, implying an elevated trophic position above the underlying microzooplankton baseline. Ontogenetic dietary shifts were observed in the BFT larvae from the GOM and MED which indicates early life trophodynamics differences between these spawning habitats. Significant trophic differences between the GOM and MED larvae were observed in relation to δ15N signatures in favour of the MED larvae, which may have important implications in their growth during their early life stages.These low δ15N levels in the zooplankton from the GOM may be an indication of a shifting isotopic baseline in pelagic food webs due to diatrophic inputs by cyanobacteria. Lack of enrichment for δ15N in BFT larvae compared to zooplankton implies an alternative grazing pathway from the traditional food chain of phytoplankton-zooplankton-larval fish. Results provide insight for a comparative characterization of the trophic pathways variability of the two main spawning grounds for BFT larvae.
authors.affiliation: Instituto Español de Oceanografía-Centro Oceanográfico de Málaga (COM-IEO), Fuengirola, Spain.
authors.forename: Raúl
authors.initials: R
authors.lastname: Laiz-Carrión
authors.affiliation: Southeast Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration (NOAA), Miami, Florida, United States of America; South Florida Campus- University of Phoenix, Miramar, Florida, United States of America.
authors.forename: Trika
authors.initials: T
authors.lastname: Gerard
authors.affiliation: Instituto Español de Oceanografía-Centro Oceanográfico de Málaga (COM-IEO), Fuengirola, Spain.
authors.forename: Amaya
authors.initials: A
authors.lastname: Uriarte
authors.affiliation: South Florida Campus- University of Phoenix, Miramar, Florida, United States of America; Cooperative Institute for Marine and Atmospheric Studies (CIMAS), University of Miami, Miami, Florida, United States of America.
authors.forename: Estrella
authors.initials: E
authors.lastname: Malca
authors.affiliation: Instituto Español de Oceanografía-Centro Oceanográfico de Málaga (COM-IEO), Fuengirola, Spain.
authors.forename: José María
authors.initials: JM
authors.lastname: Quintanilla
authors.affiliation: Princeton University Program in Atmospheric and Oceanic Science, Forrestal Campus/Sayre Hall, Princeton, New Jersey, United States of America; NOAA Geophysical Fluid Dynamics Laboratory, 201 Forrestal Road, Princeton, New Jersey, United States of America.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Muhling
authors.affiliation: Instituto Español de Oceanografía Centro Oceanográfico de Baleares (COB-IEO), Palma de Mallorca, Balearic Islands, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Alemany
authors.affiliation: South Florida Campus- University of Phoenix, Miramar, Florida, United States of America; Cooperative Institute for Marine and Atmospheric Studies (CIMAS), University of Miami, Miami, Florida, United States of America.
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Privoznik
authors.affiliation: South Florida Campus- University of Phoenix, Miramar, Florida, United States of America; Cooperative Institute for Marine and Atmospheric Studies (CIMAS), University of Miami, Miami, Florida, United States of America.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Shiroza
authors.affiliation: Southeast Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration (NOAA), Miami, Florida, United States of America.
authors.forename: John T
authors.initials: JT
authors.lastname: Lamkin
authors.affiliation: Instituto Español de Oceanografía-Centro Oceanográfico de Málaga (COM-IEO), Fuengirola, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: García
mesh_terms: D000818:Animals; D001686:Biological Phenomena / Q000502:physiology; D002247:Carbon Isotopes / Q000378:metabolism*; D004032:Diet; D004463:Ecology; D017753:Ecosystem; D005247:Feeding Behavior / Q000502:physiology; D020387:Food Chain; D060851:Gulf of America; D007814:Larva / Q000254:growth & development* / Q000378:metabolism; D019083:Mediterranean Region; D009587:Nitrogen Isotopes / Q000378:metabolism*; D009752:Nutritional Status / Q000502:physiology; D010839:Phytoplankton / Q000254:growth & development; D013696:Temperature; D014413:Tuna / Q000254:growth & development* / Q000378:metabolism; D015048:Zooplankton / Q000254:growth & development
chemical_list: D002247:Carbon Isotopes; D009587:Nitrogen Isotopes