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The settlement of demersal animals is influenced both by physical processes ruling the distribution of pelagic juveniles in the open ocean and by their active selection of suitable benthic habitats. Green turtles Chelonia mydas inhabiting the coastal areas of the western South Atlantic Ocean derive primarily from the rookery at Ascension Island and settle over a huge area spanning from northern Brazil to Uruguay. Here, we analysed the stable C and N isotope ratios in 30 µm of carapace layers from juvenile green turtles collected from 2 distinct areas of Brazil (Praia do Forte, 12°38'S, 38°05'W, and Ubatuba, 23°26'S, 45°05'W), with the goal of reconstructing their individual diets and habitat use patterns. Juvenile neritic green turtles from Praia do Forte usually had herbivorous diets, with limited individual variability and few temporal changes in diet or habitat. Conversely, most juvenile green turtles from Ubatuba had omnivorous diets, although they exhibited high levels of individual and temporal variability. These contrasting patterns could be linked to less abundant and predictable food availability in subtropical Ubatuba compared to tropical Praia do Forte. It is unknown why large numbers of juvenile green turtles bypass foraging grounds in north-eastern Brazil to settle in subtropical or warm temperate areas, although it may be related to individual differences in growth rate and their size being too small when reaching Brazil from Ascension Island.

Understanding the trophic niches of marine apex predators is necessary to understand interactions between species and to achieve sustainable, ecosystem-based fisheries management. Here, we review the stable carbon and nitrogen isotope ratios for biting marine mammals inhabiting the Atlantic Ocean to test the hypothesis that the relative position of each species within the isospace is rather invariant and that common and predictable patterns of resource partitioning exists because of constrains imposed by body size and skull morphology. Furthermore, we analyze in detail two species-rich communities to test the hypotheses that marine mammals are gape limited and that trophic position increases with gape size. The isotopic niches of species were highly consistent across regions and the topology of the community within the isospace was well conserved across the Atlantic Ocean. Furthermore, pinnipeds exhibited a much lower diversity of isotopic niches than odontocetes. Results also revealed body size as a poor predictor of the isotopic niche, a modest role of skull morphology in determining it, no evidence of gape limitation and little overlap in the isotopic niche of sympatric species. The overall evidence suggests limited trophic flexibility for most species and low ecological redundancy, which should be considered for ecosystem-based fisheries management.

Este artículo contiene 18 páginas, 4 tablas, 5 figuras., Insights into the year-round movements and behaviour of seabirds are essential to better understand their ecology and to evaluate possible threats at sea. The Atlantic petrel Pterodroma incerta is an Endangered gadfly petrel endemic to the South Atlantic Ocean, with virtually the entire population breeding on Gough Island (Tristan da Cunha archipelago). We describe adult phenology, habitat preferences and at-sea activity patterns for each phenological phase of the annual cycle and refine current knowledge about its distribution, by using light-level geolocators on 13 adults over 1−3 consecutive years. We also ascertained moulting pattern through stable isotope analysis (SIA) of nitrogen and carbon in feathers from 8 carcasses. On average, adults started their post-breeding migration on 25 December, taking 10 d to reach their non-breeding areas on the South American shelf slope. The pre-breeding migration started around 11 April and took 5 d. From phenological data, we found evidence of carry-over effects between successive breeding periods. The year-round distribution generally coincided with the potential distribution obtained from habitat modelling, except during the non-breeding and pre-laying exodus periods, when birds only used the western areas of the South Atlantic. Moulting occurred during the nonbreeding period, when birds spent more time on the water, and results from SIA helped us to distinguish feathers grown around Gough Island from those grown in the non-breeding area. Overall, our results bring important new insights into the spatial ecology of this Endangered seabird, which should help improve conservation strategies in the South Atlantic Ocean., The Ministerio de educación y Ciencia and Ministerio de Ciencia e Innovación from the Spanish Government (Projects CGL2006- 01315/BOS, CGL201342585-P, CGL2009-11278/BOS) financially supported this study. Logistical support and financial funding during field work was provided by the South African Department of Environmental Affairs and the National Research Foundation, through the South African National Antarctic Programme, with additional support from the Royal Society for the Protection of Birds. R.R., Z.Z. and J.M.R.G. were supported by Spanish MINECO (Juan de la Cierva postdoctoral programme, JCI-2012-11848), Universitat de Barcelona (UB, APIF/2012) and Spanish MECD (FPU, AP2009-2163), respectively.

Studying the feeding ecology of seabirds is important not only to understand basic aspects of their ecology and threats but also for the conservation of marine ecosystems. In this regard, tropical seabirds have been relatively neglected, and in particular the trophic ecology of tropicbirds is scarcely known. We combined GPS tracking, environmental variables and sampling of regurgitates during incubation and brooding to understand the feeding ecology of red-billed tropicbirds Phaethon aethereus as well as how foraging strategies may change between 2 contrasting marine environments: a coastal island in the Canary Current upwelling (Îles de la Madeleine) and an oceanic island in the middle of the south Atlantic (St Helena). Tropicbirds breeding on the Îles de la Madeleine headed west, foraging on and beyond the shelf slope, probably to associate with subsurface predators which bring pelagic fish close to the surface. Birds from St Helena showed a greater foraging effort and a strong attraction to areas with the greatest species richness of Scombridae, possibly due to a greater difficulty in finding prey in the oligotrophic oceanic waters. Tropicbirds ranged much beyond the extension of the protected areas around their colonies, indicating that current protected areas are insufficient for these populations. We found no evidence to suspect direct mortality of tropicbirds in regional fisheries, but overexploitation of small epipelagic fish and tuna may decrease feeding opportunities and lead to competition with fisheries. The substantial differences in foraging behaviour demonstrated by individuals from both colonies indicates that caution should be taken when extrapolating foraging patterns of tropical seabirds breeding in contrasting oceanographic environments.

The Convention on Biological Diversity aspires to designate 10% of the global oceans as Marine Protected Areas (MPAs), but so far, few MPAs protect pelagic species in the high seas. Transparent scientific approaches are needed to ensure that these encompass areas with high biodiversity value. Here we used the distribution of all globally threatened seabirds breeding in a centrally located archipelago (Tristan da Cunha) to provide guidance on where MPAs could be established in the South Atlantic Ocean. We combined year-round tracking data from six species, and used the systematic conservation-planning tool, 'Zonation', to delineate areas that would protect the largest proportion of each population. The areas used most intensively varied among species and seasons. Combining the sites used by all six species suggested that the most important areas of the South Atlantic are located south of South Africa, around the central South Atlantic between 30 degrees S and 55 degrees S, and near South America. We estimated that the longline fishing effort in these intensively used areas is around 11 million hooks on average each year, highlighting the need for improved monitoring of seabird bycatch rates and the enforcement of compliance with bird bycatch mitigation requirements by fisheries. There was no overlap between the identified areas and any of the existing MPAs in the South Atlantic. The conservation of these highly mobile, pelagic species cannot be achieved by single countries, but requires a multi-national approach at an ocean-basin scale, such as an agreement for the conservation of biodiversity beyond national jurisdiction under the United Nation Convention on the Law of the Sea.

Trophic ecology and movements are critical issues for understanding the role of marine predators in food webs and for facing the challenges of their conservation. Seabird forag- ing ecology has been increasingly studied, but small elusive species, such as those forming the 'lit- tle shearwater' complex, remain poorly known. We present the first study on the movements and feeding ecology of the Barolo shearwater Puffinus baroli baroli in a colony from the Azores archi- pelago (NE Atlantic), combining global location-sensing units, stable isotope analyses of feathers (δ 13 C and δ 15 N), stomach flushings and data from maximum depth gauges. During the chick-rear- ing period, parents visited their nests most nights, foraged mainly south of the colony and fed at lower trophic levels than during the non-breeding period. Squid was the most diverse prey (6 fam- ilies and at least 10 different taxa), but species composition varied considerably between years. Two squid families, Onychoteuthidae and Argonautidae, and the fish family Phycidae accounted for 82.3% of ingested prey by number. On average, maximum dive depths per foraging trip reached 14.8 m (range: 7.9 to 23.1 m). After the breeding period, birds dispersed offshore in all directions and up to 2500 km from the breeding colony, and fed at higher trophic levels. Overall, our results indicate that the Barolo shearwater is a non-migratory shearwater feeding at the lowest trophic level among Macaronesian seabirds, showing both diurnal and nocturnal activity and feeding deeper in the water column, principally on small schooling squid and fish. These traits contrast with those of 3 other Azorean Procellariiformes (Cory's shearwater Calonectris diomedea, the Madeiran storm-petrel Oceanodroma castro and Monteiro's storm-petrel O. monteiroi), indi- cating ecological segregation within the Azorean seabird community.

29 pages,8 figures, 9 tables, supporting information https://doi.org/10.1371/journal.pone.0151699, We examine the large-scale distribution patterns of the nano- and microphytoplankton collected from 145 oceanic stations, at 3 m depth, the 20% light level and the depth of the subsurface chlorophyll maximum, during the Malaspina-2010 Expedition (December 2010-July 2011), which covered 15 biogeographical provinces across the Atlantic, Indian and Pacific oceans, between 35°N and 40°S. In general, the water column was stratified, the surface layers were nutrient-poor and the nano- and microplankton (hereafter phytoplankton, for simplicity, although it included also heterotrophic protists) community was dominated by dinoflagellates, other flagellates and coccolithophores, while the contribution of diatoms was only important in zones with shallow nutriclines such as the equatorial upwelling regions. We applied a principal component analysis to the correlation matrix among the abundances (after logarithmic transform) of the 76 most frequent taxa to synthesize the information contained in the phytoplankton data set. The main trends of variability identified consisted of: 1) A contrast between the community composition of the upper and the lower parts of the euphotic zone, expressed respectively by positive or negative scores of the first principal component, which was positively correlated with taxa such as the dinoflagellates Oxytoxum minutum and Scrippsiella spp., and the coccolithophores Discosphaera tubifera and Syracosphaera pulchra (HOL and HET), and negatively correlated with taxa like Ophiaster hydroideus (coccolithophore) and several diatoms, 2) a general abundance gradient between phytoplankton-rich regions with high abundances of dinoflagellate, coccolithophore and ciliate taxa, and phytoplankton-poor regions (second principal component), 3) differences in dominant phytoplankton and ciliate taxa among the Atlantic, the Indian and the Pacific oceans (third principal component) and 4) the occurrence of a diatom-dominated assemblage (the fourth principal component assemblage), including several pennate taxa, Planktoniella sol, Hemiaulus hauckii and Pseudo-nitzschia spp., in the divergence regions. Our findings indicate that consistent assemblages of co-occurring phytoplankton taxa can be identified and that their distribution is best explained by a combination in different degrees of both environmental and historical influences., This work was supported by Consolider-Ingenio 2010, CSD2008-00077 of the former Spanish Ministerio de Ciencia e Innovación (ES) (Now Ministerio de Economía y Competitividad, www.mineco.gob.es); Consejo Superior de Investigaciones Científicas (CSIC) (ES)

15 pages, 5 figures, 5 tables, Aim. Apical pelagic species forage in predictable habitats, and their movements should signal biologically and ecologically significant areas of the marine ecosystem. Several countries are now engaged in identifying these areas based on animal tracking, but this is often limited to a few individuals from one breeding population, which may result in biased portrayals of the key marine habitats. To help identify such foraging areas, we compiled tracking data of a marine top predator from the main breeding colonies in the Central Macaronesia. Location. North-east Atlantic Ocean. Methods. Over seven years, we tracked the foraging movements of Cory's shearwaters (Calonectris borealis) from several populations during the chick-rearing period using global positioning system and platform terminal transmitter devices. Results. We obtained foraging trips from 174 shearwaters breeding on six important colonies representative of the range occupied in the Macaronesian Archipelagos of Madeira, Salvages and Canaries. Our results show that birds orient and move rapidly towards the closest neritic waters over the African continental shelf. Birds from different colonies show substantial spatial segregation in their foraging grounds but consistently overlap in some specific foraging areas along the Canary Current characterized by high productivity. By weighting the use of foraging grounds according to the size of each study population, we inferred the overall exploitation of such areas. Main conclusions. Our meta-population approach provides a more comprehensive picture of space use from both perspectives: the studied species and the Canary Current system. Foraging grounds consistently used by several populations may not be adequately identified by tracking a single population, and therefore, multiple population tracking studies are needed to properly delineate key conservation areas and inform conservation planning in the marine ecosystem. Finally, we highlight the long-term stability and sustainability of identified foraging areas and propose that countries with geographical jurisdictions over the Canary Current area should work towards multilateral agreements to set management plans for this key marine ecosystem, We are thankful to A. Almeida, H. Alonso, M. N. Carrasco, T. Catry, M.P. Dias, L. Gangoso, M. Lecoq, J. M. Mart ínez, R. Mart ínez, A. Padr on, J. Prieto, A. Rodr íguez, T. Militão, X. Moreno, M. L opez, J. Ferrer, L. Est evez and C. Canella for their field and logistic support. Parque Natural da Madeira and several Cabildos Insulares provided permissions and logistical support. We are also indebted with E. Batllori for helping with spatial modelling and M. Brooke for reviewing an earlier manuscript. RR, JN, VHP and JMR-G were supported by respective programmes of Beatriu de Pin os (2010-BP_A-00173), Juan de la Cierva (JCI-2009-05426), Fundac ~ao para a Ciência e Tecnologia (FCT; SFRH/BPD/63825/2009) and Formaci on de Profesorado Universitario (FPU; AP2009-2163). This study was financed by European Union (EU), the Spanish Ministerio de Educaci on y Ciencia (MEyC) and the Portuguese FCT through different projects: LIFE04NAT/ES/000049(EU), LIFE04NAT/PT/000213(EU), LIFE07NAT/E/000732(EU), LIFE09NAT/PT/000041(EU), REN2002-01164(MEyC), CGL2006-01315/BOS(MEyC), CGL2009-11278/BOS(MEyC), PTDC/MAR/71927/2006(FCT) and PEst-OE/MAR/UI0331/2011(FCT)

13 páginas, 2 figuras, 4 tablas., Feeding ecology and geographic location are 2 major factors influencing animal stable isotope signatures, but their relative contributions are poorly understood, which limits the usefulness of stable isotope analysis in the study of animal ecology. To improve our knowledge of the main sources of isotopic variability at sea, we determined δ15N and δ13C signatures in the first primary feather of adult birds from 11 Procellariiform species (n = 609) across 16 northeast Atlantic localities, from Cape Verde (20°N) to Iceland (60°N). Post-breeding areas (where the studied feather is thought to be grown) were determined using light-level geolocation for 6 of the 11 species. Isotopic variability was geographically unstructured within the mid-northeast Atlantic (Macaronesian archipelagos), but trophically structured according to species and regardless of the breeding location, presumably as a result of trophic segregation among species. Indeed, the interspecific isotopic overlap resulting from combining δ15N and δ13C signatures of seabirds was low, which suggests that most species exploited exclusive trophic resources consistently across their geographic range. Species breeding in north temperate regions (Iceland, Scotland and Northern Ireland) showed enriched N compared to the same or similar species breeding in tropical and subtropical regions, suggesting some differences in baseline levels between these regions. The present study illustrates a noticeable trophic segregation of northeast Atlantic Procellariiformes. Our results show that the isotopic approach has limited applicability for the study of animal movements in the northeast Atlantic at a regional scale, but is potentially useful for the study of long-distance migrations between large marine systems., J.L.R. and E.G.-D. were supported by a postgraduate grant from the Generalitat de Catalunya, V.N. by a postgraduate grant of the Portuguese Fundaçáo para a Ciênciaea Tecno - logia/ Foundation for Science and Technology and J.G.-S. by the Ramon y Cajal programme. This work benefited from support by the Ministerio de Ciencia e Innovación (CGL2009-11278/BOS) and Fondos Feder.

Aim Anthropogenic activities alter and constrain the structure of marine ecosystems with implications for wide-ranging marine vertebrates. In spite of the environmental importance of vast oceanic ecosystems, most conservation efforts mainly focus on neritic areas. To identify relevant oceanic areas for conservation, we assessed the year-round spatial distribution and spatio-temporal overlap of eight truly oceanic seabird species of gadfly petrels (Pterodroma spp.) inhabiting the Atlantic Ocean. Location Atlantic Ocean. Methods Using tracking data (mostly from geolocators), we examined year-round distributions, the timing of life-cycle events, and marine habitat overlap of eight gadfly petrel species that breed in the Atlantic Ocean. Results We compiled 125 year-round tracks. Movement strategies ranged from non-migratory to long-distance migrant species and from species sharing a common non-breeding area to species dispersing among multiple non-breeding sites. Gadfly petrels occurred throughout the Atlantic Ocean but tended to concentrate in subtropical regions. During the boreal summer, up to three species overlapped spatio-temporally over a large area around the Azores archipelago. During the austral summer, up to four species coincided in a core area in subtropical waters around Cape Verde, and three species shared habitat over two distinct areas off Brazil. The petrels used many national Exclusive Economic Zones, although they also exploited offshore international waters. Main conclusions Tracking movements of highly mobile vertebrates such as gadfly petrels can provide a powerful tool to evaluate and assess the potential need for and location of protected oceanic areas. As more multispecies, year-round data sets are collected from wide-ranging vertebrates, researchers and managers will have greater insight into the location of biodiversity hotspots. These can subsequently inform and guide marine spatial planning efforts that account for both conservation and sustainable use of resources such as commercial fisheries.