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Increasing atmospheric CO2 concentrations are causing ocean acidification (OA), altering carbonate chemistry with consequences for marine organisms. Here we show that OA increases by 46–212% the production of phenolic compounds in phytoplankton grown under the elevated CO2 concentrations projected for the end of this century, compared with the ambient CO2 level. At the same time, mitochondrial respiration rate is enhanced under elevated CO2 concentrations by 130–160% in a single species or mixed phytoplankton assemblage. When fed with phytoplankton cells grown under OA, zooplankton assemblages have significantly higher phenolic compound content, by about 28–48%. The functional consequences of the increased accumulation of toxic phenolic compounds in primary and secondary producers have the potential to have profound consequences for marine ecosystem and seafood quality, with the possibility that fishery industries could be influenced as a result of progressive ocean changes. Increasing atmospheric CO2 concentrations causes ocean acidification, which alters marine chemical environments with unknown consequences for marine ecosystems. Here, Gao et al. show that ocean acidification increases levels of phenolic compounds in phytoplankton and zooplankton, implying a food chain impact.

Tara Oceans particularly acknowledges the commitment of the following sponsors: the CNRS (in particular Groupement de Recherche GDR3280), the European Molecular Biology Laboratory, Genoscope/CEA, French Government “Investissements d’Avenir” programs OCEANOMICS (ANR-11-BTBR-0008) and FRANCE GENOMIQUE (ANR-10-INBS-09-08), Agence Nationale de la Recherche, and European Union FP7 (Micro B3 no. 287589). We appreciate the support and commitment of agnès b. and E. Bourgois, Veolia Environment Foundation, Region Bretagne, Lorient Agglomeration, World Courier, Illumina, Eléctricité de France Foundation, Fondation pour la recherche sur la biodiversité, Prince Albert II de Monaco Foundation, Tara Foundation, its schooner, and its teams. We are also grateful to the French Ministry of Foreign Affairs for supporting the expedition and to the countries that granted sampling permissions. Tara Oceans would not exist without continuous support from 23 institutes (http://oceans.taraexpeditions.org/en/m/science/les-labos-impliques/). This article is contribution number 52 of Tara Oceans. This study is funded by Tara Oceans and the Malaspina 2010 Expedition project (Spanish Ministry of Economy and Competitiveness, CSD2008-00077) and has received additional support from the King Abdullah University of Science and Technology through baseline funding to X.I. and C.M.D., Campus de Excelencia Internacional del Mar (CEIMAR), and PLASTREND (BBVA Foundation) and MIDaS (CTM2016-77106-R, AEI/FEDER/UE) projects. The subtropical ocean gyres are recognized as great marine accummulation zones of floating plastic debris; however, the possibility of plastic accumulation at polar latitudes has been overlooked because of the lack of nearby pollution sources. In the present study, the Arctic Ocean was extensively sampled for floating plastic debris from the Tara Oceans circumpolar expedition. Although plastic debris was scarce or absent in most of the Arctic waters, it reached high concentrations (hundreds of thousands of pieces per square kilometer) in the northernmost and easternmost areas of the Greenland and Barents seas. The fragmentation and typology of the plastic suggested an abundant presence of aged debris that originated from distant sources. This hypothesis was corroborated by the relatively high ratios of marine surface plastic to local pollution sources. Surface circulation models and field data showed that the poleward branch of the Thermohaline Circulation transfers floating debris from the North Atlantic to the Greenland and Barents seas, which would be a dead end for this plastic conveyor belt. Given the limited surface transport of the plastic that accumulated here and the mechanisms acting for the downward transport, the seafloor beneath this Arctic sector is hypothesized as an important sink of plastic debris. Peer reviewed

It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical developments and led to fundamental discoveries in the field. We show that the questions have broad applicability to other taxa, including terrestrial animals, flying insects, and swimming invertebrates, and, as such, this exercise provides a useful roadmap for targeted deployments and data syntheses that should advance the field of movement ecology. Workshop funding was granted to M.T., A.M.M.S., and C.M.D. by the UWA Oceans Institute, the Australian Institute of Marine Science, and the Office of Sponsored Research at King Abdullah University of Science and Technology (KAUST). Hays, Graeme C. et al. Peer reviewed

Se estudian, bajo condiciones de laboratorio, los estadios tempranos de desarrollo en Bryconamericus caucanus. Hembras maduras (peso promedio de 8,12g) recibieron dos dosis intraperitoneales de extracto de hipofisis de carpa (1a dosis de 0,5 mg/Kg en la hora cero y 2 dosis de 5 mg/Kg en la hora 12). Asimismo, los machos maduros recibieron una unica dosis de 0.5 mg / kg en la 2 dosis de las hembras. Se llevo a cabo desove en seco a 152,25 grados-hora luego de la aplicacion de la 2 dosis hormonal. Los huevos de B. caucanus eran amarillos, redondeados, no adhesivos y el espacio perivitelino luego de la hidratacion fue moderado. La eclosion se registro 28 h 20 min despues de la fertilizacion (594,3 grado-horas a 21C). La respuesta positiva a la hipofizacion y las caracteristicas morfologicas del huevo y del embrion de B. caucanus fueron similares a los reportes previos en otros miembros de la subfamilia Tetragonopterinae, siendo el desarrollo embrionario de B. caucanus particularmente prolongado.

Background: The spatial distribution of mangrove crabs has been commonly associated with tree zonation and abiotic factors such as ground temperature and soil granulometry. Conversely, no studies were designed to investigate the role of competition for resources and predation in shaping crab distribution in mangroves, despite these biotic factors are recognised as key determinants for spatial patterns observed in the communities colonising rocky and sandy intertidal habitats.We studied floral and faunal assemblages in two zones of a Sri Lankan mangrove, a man-made upper intertidal level and a natural eulittoral, mid-shore one. Leaf choice experiments were designed to study both feeding rate and intra and inter-specific interactions for food of sesarmid crabs in the two habitats in order to better understand crab spatial distribution. Results: The two intertidal belts differed in terms of floral composition and crab species abundance. The eulittoral zone was strongly dominated by Neosarmatium smithi, while within the elevated littoral fringe four sesarmids (N. smithi, N. asiaticum, N. malabaricum and Muradium tetragonum) were more evenly distributed. At both levels, all sesarmids showed to collect significantly more Bruguiera spp. and Rhizophora apiculata leaves than Excoecaria agallocha ones. There was no temporal segregation in feeding activity among the four species, resulting in a high interference competition for leaves. Regardless of the habitat, N. smithi was always successful in winning inter-specific fights. Conclusions: Our results showed that the elevated littoral fringe was more crowded with crabs, but was less favourable in terms of food availability and environmental conditions. The dominance of N. smithi in gathering mangrove leaves suggests that this species may segregate the other sesarmids into less favourable habitats. The present data strongly suggest for the first time that interference competition for food can contribute to shape mangrove crab spatial distribution. info:eu-repo/semantics/published SCOPUS: ar.j

Objetivo. Determinar la respuesta de los indicadores productivos al incluir palmiste (Elaeis guineensis) en dietas para la nutrición de alevines de tilapia (Oreochromis niloticus). Material y métodos. Se utilizaron 300 machos masculinizados de tilapia (4,89 ± 0,09 g) y se distribuyeron bajo un diseño completamente al azar con tres repeticiones por tratamiento (20 peces por repetición). Se utilizó palmiste para formular cinco dietas isoproteicas (30,64%), isolipídicas (7,38%) e isoenergéticas (11,84 MJ kg-1 de alimento), control (T0), 5% (T5); 10% (T10); 15% (T15) y 20% (T20) para alimentar durante 60 días. Resultados. Los peces alimentados con los tratamientos T0, T5 y T10, no mostraron diferencias significativas (p> 0.05), pero sí con T15 y T20 en la digestibilidad de los nutrientes, el crecimiento y la composición del cuerpo. La inclusión de palmiste hasta el 20% de la dieta, disminuyó el costo del alimento. Se observó un alto grado de dependencia entre el contenido de fibra detergente neutro (%), la digestibilidad aparente de la materia seca (%) y la digestibilidad aparente de la proteína (%) (R2 = 0,732 y R2 = 0,774; p <0,000), respectivamente. Conclusiones. El palmiste se puede usar hasta el 10% en dietas para alevines de tilapia, sin afectar la digestibilidad aparente de los nutrientes, el crecimiento y el contenido nutricional en todo el cuerpo. La inclusión progresiva de palmiste en las dietas, disminuyó el costo del alimento, para un cultivo de tilapia más rentable.