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"The Deepwater Horizon disaster sent millions of barrels of oil pouring into the Gulf of Mexico-straight into the water that is home to countless animals. The oil quickly coated the wings of the brown pelican, putting this already endangered species into even more risk. How were these animals rescued? Find out about the brave scientists who saved the oil-soaked birds in this graphic adventure of animal escapes. Then, learn more about other oil spills that threatened sea life around the world"--

The hydrocarbons occurring in four common species of seabird from the Brisbane River estuary area were isolated and examined by gas chromatography.

By examination of the patterns of occurrence of the hydrocarbons and by identification of hydrocarbons of recent biogenic origin it was possible to determine the hydrocarbons of petroleum origin (up to 1038 pg g-I in muscle tissue). The evidence indicates that these hydrocarbons have originated from low concentrations of similar petroleum substances in the Brisbane River estuary, a proportion having been transferred to the birds from food organisms, although other mechanisms are possible. The results show that the n-alkanes are degraded or excreted in preference to the branched and cyclic alkanes, either within the birds or before absorption.

Gillnet fisheries are generally considered environment-friendly, causing limited bottom-impact and generating high-quality fish. Nevertheless, gillnets are also associated with high risks of bycatch of non-target animals, including seabirds and marine mammals. To fulfil Denmark's obligations with regards to European legislations and other international agreements, the present report assesses for the first time the magnitude and the spatiotemporal distribution of marine mammal and seabird bycatch in Danish gillnet fisheries and proposes solutions to mitigate this bycatch. Bycatch of seabirds and marine mammals in gillnets was estimated using electronic monitoring (EM) with videos on a sample of the Danish commercial gillnet fleet (Section 2). EM systems combined video data and fine-scale tracking data, allowing to record and analyse a census of the fishing activity of 16 vessels, including bycatches of vulnerable species, between 2010 and 2016, in the North Sea, Skagerrak, Kattegat, Belt Seas and Western Baltic Sea. Monitoring focused on seabirds, harbour porpoise and seals for which it was possible to document the temporal and spatial distribution of bycatches in gillnets in areas where data had been collected and to estimate mean quarterly bycatch rates in areas where enough EM data were available, i.e. the North Sea, the Skagerrak, the Øresund and the Belt Sea. Based on these estimates, bycatch mortality at fleet-level was calculated as the product of the estimated bycatch rates and the total fleet effort, for each area and per quarter. This work revealed important seasonal variations in bycatch rates within and between fishing areas for all the considered species. Notably, more than half of all seabird bycatches occurred in quarters 1 and 4 in the Western Baltic Sea, with a mean yearly estimate of 3,249 bycatches (95% CI: 1,439-5,759). Harbour porpoises and seals were generally more impacted by gillnet fishing in quarter 3, totalling on average 2,722 porpoise bycatches per year (95% CI: 1,323-4,518) and 890 seal bycatches per year (95% CI: 299-1,646). The factors determining bycatch of seabirds, porpoises and seals in gillnets were evaluated based on interviews with commercial fishers and assessed using a modelling approach (Section 3). Skippers usually linked elevated bycatch risks to the overlap between fishing activities and marine mammal or seabird distribution. Moreover, depth, light and weather conditions, as well as the characteristics of the fishing gear (twine width, mesh size, net height and soak time) were often cited as important factors influencing bycatch. Using the EM data collected onboard Danish gillnet vessels, statistical modelling revealed that mesh size, fishing depth, distance to shore and time of the year were important contributors to the observed levels of bycatches both for seabirds and harbour porpoises. Bycatch results from a failure of animals to detect gillnets, leading to entanglement, or a failure to identify gillnets as a danger. Section 4 focuses on the behavioural and sensory ecology of harbour porpoises and seabirds to explain gillnet bycatch. The foraging behaviour of porpoises and how this relates to bycatch was analysed in the Kattegat using passive acoustic loggers. Potential mitigation methods based on behaviour, sensory abilities and diet of seabirds and harbour porpoises are also discussed. Based on the above, research was conducted to mitigate bycatch in gillnets in Denmark (Section 5). Novel mechanical alarms, or rattle pingers, were developed as a potential alternative to pingers. Low nets were trialled in the North Sea to reduce porpoise bycatches without affecting target species catches. Gillnet illumination was tested in the Øresund to limit seabird bycatch, and 10 kHz pingers were installed in a pound net in Lillebælt to control great cormorant depredation. This report concludes with recommendations to resolve the problem of bycatch of seabirds and marine mammals in Danish waters, both by increasing monitoring effort and developing appropriate mitigation methods.

This is the final version of the article. Available from the publisher via the DOI in this record. ; Unmanned aerial vehicles (UAVs) provide an opportunity to rapidly census wildlife in remote areas while removing some of the hazards. However, wildlife may respond negatively to the UAVs, thereby skewing counts. We surveyed four species of Arctic cliff-nesting seabirds (glaucous gull Larus hyperboreus, Iceland gull Larus glaucoides, common murre Uria aalge and thick-billed murre Uria lomvia) using a UAV and compared censusing techniques to ground photography. An average of 8.5% of murres flew off in response to the UAV, but >99% of those birds were non-breeders. We were unable to detect any impact of the UAV on breeding success of murres, except at a site where aerial predators were abundant and several birds lost their eggs to predators following UAV flights. Furthermore, we found little evidence for habituation by murres to the UAV. Most gulls flew off in response to the UAV, but returned to the nest within five minutes. Counts of gull nests and adults were similar between UAV and ground photography, however the UAV detected up to 52.4% more chicks because chicks were camouflaged and invisible to ground observers. UAVs provide a less hazardous and potentially more accurate method for surveying wildlife. We provide some simple recommendations for their use. ; We thank T. Leonard and the Seabird Ecological Reserves Advisory Committee for permission to work at Witless Bay, the Canadian Wildlife Service for permits to work at Newfoundland and Nunavut and the Government of Nunavut for permits to work in Nunavut. Newfoundland and Labrador Murre Fund, Bird Studies Canada and the Molson Foundation directly funded the work. An NSERC Discovery Grant, the Canada Research Chair in Arctic Ecology and Polar Continental Shelf Project also helped fund the project. We thank T. Burke, G. Sorenson, T. Lazarus and M. Guigueno for their help and J. Nakoolak for keeping us safe from bears

In Argentina, one major factor playing a significant role in the implementation of better fishing practices is related to the advent of the Marine Stewardship Council (MSC) certification schemes in marine fisheries, given that one of its component addresses the impact of fishing operations on the ecosystem (e.g. effects on the environment, related species, bycatch). In recent years, several fisheries in Argentina—ranging from coastal ice trawlers targeting the Argentine anchovy Engraulis anchoita to freezer trawlers targeting the Patagonian scallop Zygochlamys patagonica and the Patagonian grenadier or Hoki Macruronus magellanicus have been certified under the MSC scheme. Although these processes are not driven by the Government certainly creates opportunities to develop better fishing practices including in the agendas of fishermen not only target species but also other management issues affecting the marine environment. In this chapter, we will review the current status of the certification schemes implemented in the latter referred fisheries regarding seabird conservation discussing challenges and opportunities from the seabird perspective.

Seabirds and humpback whales give early warning to marine heatwaves
Lauren Bien from Prince William Sound Science Center and Mayumi Arimitsu from USGS, Alaska Science Center and additional contributors, John Moran and Rob Suryan, Alaska Fisheries Science Center explain how seabirds and humpback whales provide early warning signals during extreme marine heatwaves. Between 2014 and 2016, an extreme marine heatwave struck the North Pacific Ocean, affecting nearshore and pelagic (offshore, open-ocean) ecosystems from Southern California to Alaska. This unprecedented event, characterized by unusually warm ocean temperatures over a large area, was the longest-duration marine heatwave recorded to date. The Gulf of Alaska endured some of the most severe consequences of this heatwave, now known as the Pacific Marine Heatwave or "the Blob" (Fig. 1).

Understanding the processes driving seabirds' reproductive performance through trophic interactions requires the identification of seasonal pulses in marine productivity.We investigated the sequence of environmental and biological processes driving the reproductive phenology and performance of the storm petrel (Hydrobates pelagicus) in the Western Mediterranean. The enhanced light and nutrient availability at the onset of water stratification (late winter/early spring) resulted in annual consecutive peaks in relative abundance of phytoplankton, zooplankton and ichthyoplankton. The high energy-demanding period of egg production and chick rearing coincided with these successive pulses in food availability, pointing to a phenological adjustment to such seasonal patterns with important fitness consequences. Indeed, delayed reproduction with respect to the onset of water stratification resulted in both hatching and breeding failure. This pattern was observed at the population level, but also when confounding factors such as individuals' age or experience were also accounted for.We provide the first evidence of oceanographic drivers leading to the optimal time-window for reproduction in an inshore seabird at southern European latitudes, along with a suitable framework for assessing the impact of environmentally driven changes in marine productivity patterns in seabird performance. ; Research funds were provided by the Spanish Government (refs. BOS2003-01960, CGL2006-04325/BOS, CGL2009 08298, CGL2013-42203-R, JCI-2011-09085), and the European Union (FP7-PEOPLE 2009-IEF-MATERGLOBE) ; Peer Reviewed

Este artículo contiene 18 páginas, 7 figuras, 8 tablas. ; Fisheries have an enormous economic importance, but reconciling their socio-economic features with the conservation and sustainability of marine ecosystems presents major challenges. Bycatch mortality from fisheries is clearly among the most serious global threats for marine ecosystems, affecting a wide range of top predators. Recent estimates report ca. 200,000 seabirds killed annually by bycatch in European waters. However, there is an urgent need to rigorously estimate actual mortality rates and quantify effects of bycatch on populations. The Mediterranean Sea is one of the most impacted regions. Here, we estimate for the first time both bycatch mortality rates and their population-level effects on three endemic and vulnerable Mediterranean taxa: Scopoli's shearwater, Mediterranean shag, and Audouin's gull, that die in different types of fishing gears: longlines, gillnets and sport trolling, respectively. We use multi-event capture–recapture modelling to estimate crucial demographic parameters, including the probabilities of dying in different fishing gears. We then build stochastic demography models to forecast the viability of the populations under different management scenarios. Longline bycatch was particularly severe for adults of Scopoli's shearwaters and Audouin's gulls (ca. 28% and 23% of total mortality, respectively) and also for immature gulls (ca. 90% of mortality). Gillnets had a lower impact, but were still responsible for ca. 9% of juvenile mortality on shags, whereas sport trolling only slightly influenced total mortality in gulls. Bycatch mortality has high population-level impacts in all three species, with shearwaters having the highest extinction risk under current mortality rates. Different life-history traits and compensatory demographic mechanisms between the three species are probably influencing the different bycatch impact: for shearwaters, urgent conservation actions are required to ensure the viability of their populations. Results will be very useful for guiding future seabird conservation policies and moving towards an ecosystem-based approach to sustainable fisheries management. ; Regional Government of the Balearic Islands; European Social Fund; Spanish Ministry of Economy, Grant/Award Number: CGL2013-42203-R; European Union, Grant/Award Number: H2020- 634495 ; Peer reviewed