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Marine predators are monitored as indicators of pollution, but such trends can be complicated by variation in diet. Glaucous-winged gulls (

The use of unmanned aerial vehicles, or drones, in wildlife monitoring has increased in recent years, particularly in hard-to-access habitats. We used fixed-wing and quadcopter drones to census an urban-nesting population of Glaucous-winged Gulls in Victoria, Canada. We conducted our study over 2 years and asked whether (i) drones represent a suitable survey method for rooftop-nesting gulls in our study region; and (ii) Victoria’s urban gull population had increased since the last survey >30 years earlier. Using orthomosaic imagery derived from drone overflights, we estimated at least a threefold increase over the 1986 count reported for the entire city (from 114 to 346 pairs), and an approximate tenfold increase in the number of gulls nesting in the downtown core. Drones proved to be an excellent platform from which to census rooftop-nesting birds: occupied nests were readily discernible in our digital imagery, and incubating birds were undisturbed by drones. This lack of disturbance may be due to Victoria’s location in an aerodrome; gulls experience dozens of floatplane and helicopter flights per day and are likely habituated to air traffic. Glaucous-winged Gulls have declined considerably at their natural island colonies in the region since the 1980s. Our results indicate that although urban roofs provide replacement nesting habitat for this species, local gull populations have not simply relocated en masse from islands to rooftops in the region.

We review the precautionary approach to fisheries management, propose a framework that will allow a systematic assessment of insufficient precaution and provide an illustration using an Antarctic fishery. For a single-species fishery, our framework includes five attributes: (1) limit reference points that recognize gaps in our understanding of the dynamics of the species; (2) accurate measures of population size; (3) ability to detect population changes quickly enough to arrest unwanted declines; (4) adequate understanding of ecosystem dynamics to avoid adverse indirect effects; and (5) assessment of the first four elements by a sufficiently impartial group of scientists. We argue that one or more of these elements frequently fail to be present in the management of many fisheries. Structural uncertainties, which characterize almost all fisheries models, call for higher limit points than those commonly used. A detailed look into the five elements and associated uncertainties is presented for the fishery on the Antarctic toothfish in the Ross Sea (FAO/CCAMLR Area 88.1, 88.2), for which management was recently described as ‘highly precautionary’. In spite of having features that make the Ross Sea fishery ideal for the application of the precautionary approach, gaps in our knowledge and failure to acknowledge these gaps mean that current regulation falls short of being sufficiently precautionary. We propose some possible remedies.

As conspicuous midtrophic omnivores, gulls can serve as useful indicators to characterize long-term ecological changes in marine ecosystems. Glaucous-winged Gulls (Larus glaucescens) have been studied in the Georgia Basin of British Columbia, Canada, an urbanized coastal zone, since the late 1800s. We collated all available information to develop a (noncontinuous) 111-year time series of counts at breeding colonies, and combined these counts with demographic vital rates to assess how changes in historical gull egg harvesting practices, forage fish abundance, and Bald Eagle (Haliaeetus leucocephalus) numbers affected gull population trajectories from 1900 to 2010. Mean counts at 87 breeding colonies in the Georgia Basin showed a nonlinear trend, increasing from historical low counts in the early part of the twentieth century to peak values in the 1980s, and declining thereafter to the end of the time series. Demographic models that integrated temporal trends in clutch size and nesting success, and...

The world's oceans have undergone significant ecological changes following European colonial expansion and associated industrialization. Seabirds are useful indicators of marine food web structure and can be used to track multidecadal environmental change, potentially reflecting long-term human impacts. We used stable isotope (δ(13)C, δ(15)N) analysis of feathers from glaucous-winged gulls (Larus glaucescens) in a heavily disturbed region of the northeast Pacific to ask whether diets of this generalist forager changed in response to shifts in food availability over 150 years, and whether any detected change might explain long-term trends in gull abundance. Sampled feathers came from birds collected between 1860 and 2009 at nesting colonies in the Salish Sea, a transboundary marine system adjacent to Washington, USA and British Columbia, Canada. To determine whether temporal trends in stable isotope ratios might simply reflect changes to baseline environmental values, we also analysed muscle tissue from forage fishes collected in the same region over a multidecadal timeframe. Values of δ(13)C and δ(15)N declined since 1860 in both subadult and adult gulls (δ(13)C, ~ 2-6‰; δ(15)N, ~4-5‰), indicating that their diet has become less marine over time, and that birds now feed at a lower trophic level than previously. Conversely, forage fish δ(13)C and δ(15)N values showed no trends, supporting our conclusion that gull feather values were indicative of declines in marine food availability rather than of baseline environmental change. Gradual declines in feather isotope values are consistent with trends predicted had gulls consumed less fish over time, but were equivocal with respect to whether gulls had switched to a more garbage-based diet, or one comprising marine invertebrates. Nevertheless, our results suggest a long-term decrease in diet quality linked to declining fish abundance or other anthropogenic influences, and may help to explain regional population declines in this species and other piscivores.

A review of 135 accounts of predation on seahorses and pipefishes identified 82 predator species, with nine species of seahorses and 25 of pipefishes recorded as prey. These cryptic fishes were generally depredated in low numbers. Where syngnathids formed a high proportion of predator diets, predation occurred on (1) a single abundant species during a population boom or large die-off, (2) concentrations of individuals utilising floating marine vegetation, or (3) juveniles when abundant during the breeding season. Predation coinciding with high syngnathid densities suggests their predators are foraging opportunistically rather than targeting syngnathids as prey. Invertebrates, fishes, sea turtles, waterbirds and marine mammals were all syngnathid predators: these included taxa that do not frequent the demersal habitat generally occupied by seahorses and pipefishes. Thus, seahorses and pipefishes may be moving in the open ocean more than suspected, perhaps using floating mats of marine vegetation. If so, this behaviour could act as a hitherto unknown vector for syngnathid movement and dispersal. Information on syngnathid abundance in predator diet (measured as percent number, volume, or mass) was available in 45 reviewed accounts; in 27% (n = 12) of these studies seahorses or pipefishes comprised ≥20% of predator diet (range 0.005–100%). Frequency of occurrence (percent stomachs, seabird bill-loads, or regurgitations in which a prey item occurred) was provided in 39 accounts, with 15% (n = 6) of these recording a frequency of ≥20% (range 0.003–65%).

Recently, Ballance et al. (2006) revived the hypothesis that cetaceans were a major force in the structuring of Southern Ocean food webs, and suggested that they are still playing a keystone role even as their loss continues (see also review in Mori and Butterworth 2006), a subject that we herein would like to emphasize. According to this hypothesis, following 60 yr of directed industrial whaling (Tonnessen and Johnsen 1982, Baker and Clapham 2002), the demise of the great whales (blue, Balaenoptera musculus intermedia; fin, B. physalus; and humpback, Megaptera novaeangliae) led to changes in populations and demographic parameters among penguins, seals, and minke whales (B. bonaerensis; see also Laws 1977, Bengtson and Laws 1985). These changes to populations of the great whales’ competitors came about upon release from trophic competition as a result of the "krill surplus" that ensued (i.e., of Antarctic krill, Euphausia superba; Bengtson and Laws 1985).

A major mid-1980s shift in ecological structure of significant portions of the Southern Ocean was partially due to the serial depletion of fish by intensive industrial fishing, rather than solely to climate factors as previously hypothesized. Over a brief period (1969‐1973), several finfish stocks were on average reduced to

We used 116-years of floral and faunal records from Mandarte Island, British Columbia, Canada, to estimate the indirect effects of humans on plant communities via their effects on the population size of a surface-nesting, colonial seabird, the Glaucous-winged gull (Larus glaucescens). Comparing current to historical records revealed 18 extirpations of native plant species (32% of species historically present), 31 exotic species introductions, and one case of exotic introduction followed by extirpation. Contemporary surveys indicated that native species cover declined dramatically from 1986 to 2006, coincident with the extirpation of ‘old-growth’ conifers. Because vegetation change co-occurred with an increasing gull population locally and regionally, we also tested predictions from the hypothesis that the presence and activities of seabirds help to explain those changes. Specifically, we predicted we would observe high nutrient loading and exotic plant species richness and cover on nearby islands with versus without gull colonies as a consequence of competitive dominance in species adapted to high soil nitrogen and trampling. As predicted, we found that native plant species cover and richness were lower, and exotic species cover and richness higher, on islands with versus without gull colonies. In addition, we found that soil carbon and nitrogen on islands with nesting gulls were positively related to soil depth and exotic species richness and cover across plots and islands. Our results suggest that gulls have the potential to drive rapid change in insular plant communities by increasing nutrients and disturbing vegetation. Because human activities have contributed to long-term change in gull populations, our results further suggest compelling, indirect links between human management decisions and plant community composition on islands of the Georgia Basin.

Funding for R. Bruintjes, J. Purser, A. N. Radford, S. D, Simpson and M. A. Wale was provided by the UK Department for Environment Food and Rural Affairs (Defra). N.D. Merchant received travel funding from Ocean Networks Canada. RW was supported by a Marie Curie International Incoming Fellowship within the 7th European Community Framework Programme (Project CONCEAL, FP7, PIIF-GA-2009-253407), and received travel funding to attend IMCC3 from the Society for Conservation Biology (SCB) Marine Section and the International Whaling Commission’s Climate Change steering group (with thanks to Mark Simmonds). A.J. Wright also received travel funding to attend IMCC3 from the SCB Marine Section. Date of Acceptance: 28/05/2015 Anthropogenic underwater noise is now recognized as a world-wide problem, and recent studies have shown a broad range of negative effects in a variety of taxa. Underwater noise from shipping is increasingly recognized as a significant and pervasive pollutant with the potential to impact marine ecosystems on a global scale. We reviewed six regional case studies as examples of recent research and management activities relating to ocean noise in a variety of taxonomic groups, locations, and approaches. However, as no six projects could ever cover all taxa, sites and noise sources, a brief bibliometric analysis places these case studies into the broader historical and topical context of the peer-reviewed ocean noise literature as a whole. The case studies highlighted emerging knowledge of impacts, including the ways that non-injurious effects can still accumulate at the population level, and detailed approaches to guide ocean noise management. They build a compelling case that a number of anthropogenic noise types can affect a variety of marine taxa. Meanwhile, the bibliometric analyses revealed an increasing diversity of ocean noise topics covered and journal outlets since the 1940s. This could be seen in terms of both the expansion of the literature from more physical interests to ecological impacts of noise, management and policy, and consideration of a widening range of taxa. However, if our scientific knowledge base is ever to get ahead of the curve of rapid industrialization of the ocean, we are going to have to identify naïve populations and relatively pristine seas, and construct mechanistic models, so that we can predict impacts before they occur, and guide effective mitigation for the most vulnerable populations. Publisher PDF

Historical research is playing an increasingly important role in marine sciences. Historical data are also used in policy making and marine resource management, and have helped to address the issue of shifting baselines for numerous species and ecosystems. Although many important research questions still remain unanswered, tremendous developments in conceptual and methodological approaches are expected to contribute to a comprehensive understanding of the global history of human interactions with life in the seas. Based on our experiences and knowledge from the ‘‘History of Marine Animal Populations’’ project, this paper identifies the emerging research topics for future historical marine research. It elaborates on concepts and tools which are expected to play a major role in answering these questions, and identifies geographical regions which deserve future attention from marine environmental historians and historical ecologists

Marine mammals are ecologically and culturally important species, and various countries have specific legislation to protect the welfare of individual marine mammals and the conservation of their populations. Anthropogenic noise represents a particular challenge for conservation and management. There is a large and growing body of research to support the conclusion that anthropogenic noise can affect marine mammal behavior, energetics, and physiology. The legal, policy, and management issues surrounding marine mammals and noise are similarly complex. Our objective is twofold. First, we discuss how policy and legal frameworks in Canada have some important differences from other jurisdictions covered in previous reviews, and provide a useful general case study. Secondly, we highlight some priority research areas that will improve marine mammal conservation and management. Our examples focus on the research needed to meet stated conservation objectives for marine mammal species in waters under Canadian jurisdiction.

This paper examines the location, intensity, and frequency of zodiac landings by passengers on tourist ships in the Antarctic Peninsula region during 10 seasons, 1989/90 through 1998/99. In this period, the number of passengers increased 307%, from 2460 to 10,013. Zodiac landings have occurred at 165 Peninsula region sites, concentrating in the South Shetland Islands and the northwestern part of the Peninsula. From 1989/90 to 1998/99, the number of zodiac landings in the Peninsula region increased 423%, from 164 to 858. The most visited sites are identified, as are sites experiencing increases in the second half of this 10-year period. The 10 and 20 sites experiencing the most zodiac landings each season consistently account for approximately 55% and 75% of that season's landings, respectively. Based on 1998/99 data, sites with high or medium species diversity or with high or moderate sensitivity to potential environmental disturbance account for a significant percentage of landings. Recommendations are presented for improving the assessment of potential environmental impacts at zodiac landing sites, and for improved methods of reporting site visits by the tour operators involved.

We used stable isotope techniques to analyze tissues of Keen's mice (Peromyscus keeni) and Townsend's voles (Microtus townsendii cowani) and a subset of prey items at Triangle Island, British Columbia, western Canada's largest seabird colony. Isotope analysis allowed us to investigate the importance of seabird prey in rodent diets in a system where seabirds and non-introduced rodents occur sympatrically. The δ15N values for terrestrial plants and terrestrial invertebrates on Triangle Island exceeded levels found in many terrestrial biomes and are typical of localities with high inputs of marine-derived N. We used multiple-source mixing models to estimate the relative inputs of potential prey items to vole and mouse diets. The δ13C and δ15N values of liver and muscle tissues of voles indicate that voles on Triangle Island derived their protein primarily from terrestrial plants, with some contribution by terrestrial invertebrates. In contrast, isotopic values of liver and muscle tissues of mice on Triangle Island indicated that mice prey primarily on seabird eggs and terrestrial invertebrates. Our results show that egg predation on Triangle Island is a general phenomenon in the mouse population, rather than occurring in only a few specialist feeders. Mice appear to feed on eggs once they become available and continue to utilize seabird prey, likely in the form of abandoned eggs or carcasses of chicks and adults, throughout the breeding season.

This paper presents new census data and population estimates for penguins, blue-eyed shags, and southern giant petrels from 26 sites in the Antarctic Peninsula, collected by the Antarctic Site Inventory from 1994 to 2000. For nine sites, population data or estimates are published for the first time. The newly discovered gentoo penguin population of 215 nests at Herofna Island (63°24'S, 54°36'W) represents the easternmost location where this species has been found breeding in the Peninsula. All three pygoscelid penguins — gentoo, Adelie, and chinstrap — were found breeding at Gourdin Island (63° 12'S, 57° 18'W), the fourth known site where these species nest contiguously in the Peninsula. During the period, significant declines in nesting populations of blue-eyed shag were documented at three northwestern Peninsula locations.

Eckener Point (64° 26′S; 61° 36′W) lies on the northeast side of the entrance to Charlotte Bay and southeast of Murray Island, on the west coast of Graham Land, Antarctic Peninsula (Fig. 1). Data from a 1987 census (Woehler 1993) show 40 breeding pairs of chinstrap penguinsPygoscelis antarcticaat the site. An unpublished report of 180 nests of blue-eyed cormorantPhalacrocorax atriceps/bransfieldensis(S Poncet, personal communication, 2004) in 1983 is the only other ornithological record for the site. Here we report on the results of a brief survey conducted to document the breeding seabirds for this locality. Suitable ice-free sites on the Antarctic Peninsula are limited, and Eckener Point, though small, provides nesting habitat for a high number of avian species. Plant and lichen diversity also appears unusually high.

Predation by Keen's mice (Peromyscus keeni) was the single greatest cause of egg loss for Rhinoceros Auklets (Cerorhinca monocerata) at the seabird colony on Triangle Island, British Columbia in 1998. Despite studies suggesting that gape-limited ro- dents are unable to open large eggs, mouse depredation was likely responsible for the loss of more eggs than all other causes combined, with mice commonly open- ing and eating eggs of nearly twice their mass. In one study plot, mice depredated up to 34% of eggs. This high predation rate is likely related to temporary egg neglect by foraging parents. We suggest that egg dep- redation may increase in years of low marine produc- tivity, when adults increase foraging time.

The ocean provides food, economic activity, and cultural value for a large proportion of humanity. Our knowledge of marine ecosystems lags behind that of terrestrial ecosystems, limiting effective protection of marine resources. We describe the outcome of 2 workshops in 2011 and 2012 to establish a list of important questions, which, if answered, would substantially improve our ability to conserve and manage the world’s marine resources. Participants included individuals from academia, government, and nongovernment organizations with broad experience across disciplines, marine ecosystems, and countries that vary in levels of development. Contributors from the fields of science, conservation, industry, and government submitted questions to our workshops, which we distilled into a list of priority research questions. Through this process, we identified 71 key questions. We grouped these into 8 subject categories, each pertaining to a broad component of marine conservation: fisheries, climate change, other anthropogenic threats, ecosystems, marine citizenship, policy, societal and cultural considerations, and scientific enterprise. Our questions address many issues that are specific to marine conservation, and will serve as a road map to funders and researchers to develop programs that can greatly benefit marine conservation. Setenta y Un Preguntas Importantes para la Conservación de la Biodiversidad Marina Resumen Los océanos proporcionan alimento, actividad económica y valor cultural para una gran porción de la humanidad. Nuestro conocimiento de los ecosistemas marinos está atrasado con respecto al que tenemos de los ecosistemas terrestres, lo que limita la protección efectiva de los recursos naturales. Describimos el resultado de dos talleres en 2011 y 2012 para establecer una lista de preguntas importantes, las cuales al ser respondidas, mejorarían sustancialmente nuestra habilidad de conservar y manejar los recursos marinos del mundo. Entre los participantes se incluyeron a individuos de la docencia, el gobierno y organizaciones no-gubernamentales, con una amplia experiencia que atraviesa disciplinas, ecosistemas marinos y países que varían en el nivel de desarrollo. Los contribuyentes de los campos de la ciencia, la conservación, la industria y el gobierno, presentaron preguntas a nuestros talleres, las cuales separamos en una lista de preguntas de investigación prioritarias. Por medio de este proceso, identificamos 71 preguntas clave. Las agrupamos en ocho categorías temáticas, cada una perteneciente a un componente amplio de la conservación marina: pesquerías, cambio climático, otras amenazas antropogénicas, ecosistemas, ciudadanía marina, política, consideraciones sociales y culturales, y la iniciativa científica. Nuestras preguntas se dirigen a muchas cuestiones que son específicas de la conservación marina, y servirán como una ruta a seguir para patrocinadores e investigadores que busquen desarrollar programas que puedan beneficiar ampliamente a la conservación marina.

Investigations in recent years of the ecological structure and processes of the Southern Ocean have almost exclusively taken a bottom-up, forcing-by-physical-processes approach relating various species' population trends to climate change. Just 20 years ago, however, researchers focused on a broader set of hypotheses, in part formed around a paradigm positing interspecific interactions as central to structuring the ecosystem (forcing by biotic processes, top-down), and particularly on a “krill surplus” caused by the removal from the system of more than a million baleen whales. Since then, this latter idea has disappeared from favour with little debate. Moreover, it recently has been shown that concurrent with whaling there was a massive depletion of finfish in the Southern Ocean, a finding also ignored in deference to climate-related explanations of ecosystem change. We present two examples from the literature, one involving gelatinous organisms and the other involving penguins, in which climate has been used to explain species' population trends but which could better be explained by including species interactions in the modelling. We conclude by questioning the almost complete shift in paradigms that has occurred and discuss whether it is leading Southern Ocean marine ecological science in an instructive direction.

We found plastic particles in the stomachs of 8 of the 11 species of seabirds caught as bycatch in the pelagic waters of the eastern North Pacific (41–50°N, 131–134°W). Plastic was found in all surface-feeding birds (two stormpetrel, one albatross, one petrel and one fulmar species) and in 75% of shearwaters. Densities in some stormpetrels, shearwaters and the petrel were possibly sufficient to impede digestion, but were negligible in other birds. Plastic was also found in two diving species (puffins) but absent in three others (murre, auklet and murrelet). Of 353 anthropogenic items examined, 29% were industrial pellets and 71% were fragments of discarded products (‘user’ plastic), with user plastic making up 60% of total mass. Our study is evidence of widespread plastic pollution affecting birds in a previously unsampled sector of the North Pacific.

We are among the scientists objecting to the eco-certification of Ross Sea Antarctic toothfish (Dissostichus mawsoni), as described by E. Stokstad in his News Focus story "Behind the eco-label, a debate over Antarctic toothfish" (24 September, p. 1596). The public perceives a certification by the Marine Stewardship Council (MSC) to mean an environmentally friendly fishery, not one characterized by the "dearth of key data" as indicated in the article.

We applaud DR Griffith (Front Ecol Environ 2008; 6[4]: 191–98) for addressing important fisheries management issues, but question the applicability of his solution (individual fishing quotas, IFQs) to the majority of the world’s fishing effort. Griffith’s IFQ success stories poorly represent the artisanal (small-scale) fleets that take 28–58% of global catch and employ 99% of the world’s ~51 million fishers (Berkes et al. 2001).

The Report “A global map of human impact on marine ecosystems” (B. S. Halpern et al. , 15 February, p. [948][1]) provides a timely overview of anthropogenic effects on even the farthest reaches of Earth's oceans. However, we contend that, for at least one region, using data from only the past decade leads to misleading results. A widespread perception exists that waters south of the Antarctic Polar Frontal Zone—i.e., the Southern Ocean (SO)—are still nearly pristine ([1][2], [2][3]). In fact, the northern portion of the SO saw virtually all cetacean populations removed long ago ([3][4]), and in subsequent years (1960s to 1980s) the largest stocks of demersal fish in the Indian Ocean and Scotia Sea/Atlantic Ocean sectors were also fished to commercial extinction ([4][5], [5][6]). Historically exploited fish species and cetaceans show little signs of recovery in the SO, and recent legal commercial fishing activity has been correspondingly low ([6][7]). It is thus no surprise that the modeling used by Halpern et al . shows little anthropogenic impact in these sectors apart from that of climate change. The authors acknowledge that accounting for current illegal, unregulated, and unreported fishing in these waters might show increased human impacts. The additional consideration of historical data should cause Halpern et al . to temper their conclusion that for the world's oceans “large areas of relatively little human impact remain, particularly near the poles.” 1. 1.[↵][8]1. J. P. Croxall, 2. P. N. Trathan, 3. E. J. Murphy , Science 297, 1510 (2002). [OpenUrl][9][Abstract/FREE Full Text][10] 2. 2.[↵][11]1. V. Smetacek, 2. S. Nicol , Nature 437, 367 (2005). [OpenUrl][12] 3. 3.[↵][13]1. J.A. Estes, 2. D.P. Demaster, 3. D.F. Doak, 4. T.E. Williams, 5. R. L. Brownell Jr. 1. L. Ballance 2. et al. , in Whales, Whaling and Ocean Ecosystems, J.A. Estes, D.P. Demaster, D.F. Doak, T.E. Williams, R. L. Brownell Jr., Eds. (Univ. of California Press, Berkeley, CA, 2006), pp. 215-230. 4. 4.[↵][14]1. O. Gon, 2. P. C. Heemstra , Fishes of the Southern Ocean (J. L. B. Smith Institute of Ichthyology, Grahamstown, South Africa, 1990). 5. 5.[↵][15]1. K.-H. Kock , Antarctic Fish and Fisheries (Cambridge Univ. Press, Cambridge, 1992). 6. 6.[↵][16]Fishery Reports, Convention on the Conservation of Antarctic Marine Living Resources ([www.ccamlr.org/pu/e/e_pubs/fr/drt.htm][17]). [1]: /lookup/doi/10.1126/science.1149345 [2]: #ref-1 [3]: #ref-2 [4]: #ref-3 [5]: #ref-4 [6]: #ref-5 [7]: #ref-6 [8]: #xref-ref-1-1 "View reference 1. in text" [9]: {openurl}?query=rft.jtitle%253DScience%26rft.stitle%253DScience%26rft.aulast%253DCroxall%26rft.auinit1%253DJ.%2BP.%26rft.volume%253D297%26rft.issue%253D5586%26rft.spage%253D1510%26rft.epage%253D1514%26rft.atitle%253DEnvironmental%2BChange%2Band%2BAntarctic%2BSeabird%2BPopulations%26rft_id%253Dinfo%253Adoi%252F10.1126%252Fscience.1071987%26rft_id%253Dinfo%253Apmid%252F12202819%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [10]: /lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6Mzoic2NpIjtzOjU6InJlc2lkIjtzOjEzOiIyOTcvNTU4Ni8xNTEwIjtzOjQ6ImF0b20iO3M6MjU6Ii9zY2kvMzIxLzU4OTUvMTQ0My4yLmF0b20iO31zOjg6ImZyYWdtZW50IjtzOjA6IiI7fQ== [11]: #xref-ref-2-1 "View reference 2. in text" [12]: {openurl}?query=rft.jtitle%253DNature%26rft.volume%253D437%26rft.spage%253D367%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [13]: #xref-ref-3-1 "View reference 3. in text" [14]: #xref-ref-4-1 "View reference 4. in text" [15]: #xref-ref-5-1 "View reference 5. in text" [16]: #xref-ref-6-1 "View reference 6. in text" [17]: http://www.ccamlr.org/pu/e/e_pubs/fr/drt.htm