WorldWideScience

Sample records for current seabird avoidance

  1. Business Plan for the Conservation of Pacific Seabirds: A 5-Year Plan to Help Secure Alaskan Seabirds, Seabirds of the California Current, Chilean Seabirds and Hawaiian Seabirds

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The National Fish and Wildlife Foundation’s Pacific Seabird Program will yield unprecedented gains in the conservation status of ten nationally imperiled seabird...

  2. 50 CFR Table 20 to Part 679 - Seabird Avoidance Gear Requirements for Vessels, based on Area, Gear, and Vessel Type. (See § 679...

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Seabird Avoidance Gear Requirements for Vessels, based on Area, Gear, and Vessel Type. (See § 679.24(e) for complete seabird avoidance program...) FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Table 20 Table 20 to Part 679—Seabird...

  3. Seabird diversity hotspot linked to ocean productivity in the Canary Current Large Marine Ecosystem

    Science.gov (United States)

    Attrill, Martin J.; Becker, Peter H.; Egevang, Carsten; Furness, Robert W.; Grémillet, David; Kopp, Matthias; Lescroël, Amélie; Matthiopoulos, Jason; Peter, Hans-Ulrich; Phillips, Richard A.

    2016-01-01

    Upwelling regions are highly productive habitats targeted by wide-ranging marine predators and industrial fisheries. In this study, we track the migratory movements of eight seabird species from across the Atlantic; quantify overlap with the Canary Current Large Marine Ecosystem (CCLME) and determine the habitat characteristics that drive this association. Our results indicate the CCLME is a biodiversity hotspot for migratory seabirds; all tracked species and more than 70% of individuals used this upwelling region. Relative species richness peaked in areas where sea surface temperature averaged between 15 and 20°C, and correlated positively with chlorophyll a, revealing the optimum conditions driving bottom-up trophic effects for seabirds. Marine vertebrates are not confined by international boundaries, making conservation challenging. However, by linking diversity to ocean productivity, our research reveals the significance of the CCLME for seabird populations from across the Atlantic, making it a priority for conservation action. PMID:27531154

  4. 50 CFR Table 19 to Part 679 - Seabird Avoidance Gear Codes

    Science.gov (United States)

    2010-10-01

    ... groundline for the purpose of sinking the hook-and-line gear more quickly and preventing seabirds from... hours). Line Shooter: A hydraulic device designed to deploy hook-and-line gear at a speed...

  5. The evolution of seabirds in the Humboldt Current: new clues from the Pliocene of Central Chile.

    Directory of Open Access Journals (Sweden)

    Martín Chávez Hoffmeister

    Full Text Available BACKGROUND: During the last decade, new Neogene fossil assemblages from South America have revealed important clues about the evolution of seabird faunas in one of the major upwelling systems of the world: the Humboldt Current. However, most of this record comes from arid Northern Chile and Southern Peru and, in consequence, our knowledge of the evolutionary history of seabirds in the temperate transitional zone is negligible. A new Late Pliocene assemblage of fossil birds from the coastal locality of Horcon in Central Chile offers a unique opportunity to fill this gap. PRINCIPAL FINDINGS: Isolated bones of a medium-sized penguin are the most abundant bird remains. Morphological and cladistic analyses reveal that these specimens represent a new species of crested penguin, Eudyptes calauina sp. nov. Eudyptes is a penguin genus that inhabit temperate and subantarctic regions and currently absent in central Chile. Additionally, a partial skeleton of a small species of cormorant and a partial tarsometatarsus of a sooty shearwater have been identified. CONCLUSION/SIGNIFICANCE: The Horcon fossils suggest the existence of a mixed avifauna in central Chile during the Pliocene in concordance with the latitudinal thermal gradient. This resembles the current assemblages from the transitional zone, with the presence of species shared with Northern Chile and Southern Peru and a previously unrecorded penguin currently absent from the Humboldt System but present in the Magellanic region. Comparison of Pliocene seabird diversity across the Pacific coast of South America shows that the Horcon avifauna represents a distinctive assemblage linking the living faunas with the Late Miocene ones. A comparison with the fossil record near the Benguela Current (west coast of southern Africa suggests that the thermic gradient could play an important role in the preservation of a higher diversity of cold/temperate seabirds in the Humboldt Current.

  6. Global Seabird Ammonia Emissions

    Science.gov (United States)

    Riddick, S. N.; Blackall, T. D.; Dragosits, U.; Daunt, F. H.; Braban, C. F.; Tang, Y. S.; Trathan, P.; Wanless, S.; Sutton, M. A.

    2010-12-01

    may have far reaching impact on the supply of nitrogen from seabird colonies to their current local ecosystems.

  7. Where the wild things are: predicting hotspots of seabird aggregations in the California Current System.

    Science.gov (United States)

    Nur, Nadav; Jahncke, Jaime; Herzog, Mark P; Howar, Julie; Hyrenbach, K David; Zamon, Jeannette E; Ainley, David G; Wiens, John A; Morgan, Ken; Ballance, Lisa T; Stralberg, Diana

    2011-09-01

    Marine protected areas (MPAs) provide an important tool for conservation of marine ecosystems. To be most effective, these areas should be strategically located in a manner that supports ecosystem function. To inform marine spatial planning and support strategic establishment of MPAs within the California Current System, we identified areas predicted to support multispecies aggregations of seabirds ("hotspots"). We developed habitat-association models for 16 species using information from at-sea observations collected over an 11-year period (1997-2008), bathymetric data, and remotely sensed oceanographic data for an area from north of Vancouver Island, Canada, to the USA/Mexico border and seaward 600 km from the coast. This approach enabled us to predict distribution and abundance of seabirds even in areas of few or no surveys. We developed single-species predictive models using a machine-learning algorithm: bagged decision trees. Single-species predictions were then combined to identify potential hotspots of seabird aggregation, using three criteria: (1) overall abundance among species, (2) importance of specific areas ("core areas") to individual species, and (3) predicted persistence of hotspots across years. Model predictions were applied to the entire California Current for four seasons (represented by February, May, July, and October) in each of 11 years. Overall, bathymetric variables were often important predictive variables, whereas oceanographic variables derived from remotely sensed data were generally less important. Predicted hotspots often aligned with currently protected areas (e.g., National Marine Sanctuaries), but we also identified potential hotspots in Northern California/Southern Oregon (from Cape Mendocino to Heceta Bank), Southern California (adjacent to the Channel Islands), and adjacent to Vancouver Island, British Columbia, that are not currently included in protected areas. Prioritization and identification of multispecies hotspots will

  8. Seabird drift as a proxy to estimate surface currents in the western Mediterranean?

    Science.gov (United States)

    Gomez-Navarro, Laura; Sánchez-Román, Antonio; Pascual, Ananda; Fablet, Ronan; Hernandez-Carrasco, Ismael; Mason, Evan; Arcos, José Manuel; Oro, Daniel

    2017-04-01

    Seabird trajectories can be used as proxies to investigate the dynamics of marine systems and their spatiotemporal evolution. Previous studies have mainly been based on analyses of long range flights, where birds are travelling at high velocities over long time periods. Such data have been used to study wind patterns, and areas of avian feeding and foraging have also been used to study oceanic fronts. Here we focus on "slow moving" periods (which we associate to when birds appear to be drifting on the sea surface), in order to investigate bird drift as a proxy for sea surface currents in the western Mediterranean Sea. We analyse trajectories corresponding to "slow moving" periods recorded by GPSs attached to individuals of the species Calonectris diomedea ( Scopoli's shearwater) from mid August to mid September 2012. The trajectories are compared with sea level anomaly (SLA), sea surface temperature (SST), Finite Size Lyapunov Exponents (FSLE), wind fields, and the outputs from an automated sea-surface-height based eddy tracker. The SLA and SST datasets were obtained from the Copernicus Marine Environment Monitoring Service (CMEMS) with a spatial resolution of 1/8 ̊ and 1/100 ̊ respectively while the FSLEs were computed from the SLA dataset. Finally, the wind data comes from the outputs of the CCMPv2 numerical model. This model has a global coverage with a spatial resolution of 1/4 ̊. Interesting relationships between the trajectories and SLA fields are found. According to the angle between the SLA gradient and the trajectories of birds, we classify drifts into three scenarios: perpendicular, parallel and other, which are associated with different driving forces. The first scenario implies that bird drift is driven by geostrophic sea surface currents. The second we associate with wind drag as the main driving force. This is validated through the wind dataset. Moreover, from the SST, FSLEs and the eddy tracker, we obtain supplementary information on the presence

  9. Seabirds - Alaska's most neglected resource

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Our purpose in this paper is to describe the nature of current and potential problems confronting seabirds in Alaska and to identify approaches to management and...

  10. Current development of UAV sense and avoid system

    Science.gov (United States)

    Zhahir, A.; Razali, A.; Mohd Ajir, M. R.

    2016-10-01

    As unmanned aerial vehicles (UAVs) are now gaining high interests from civil and commercialised market, the automatic sense and avoid (SAA) system is currently one of the essential features in research spotlight of UAV. Several sensor types employed in current SAA research and technology of sensor fusion that offers a great opportunity in improving detection and tracking system are presented here. The purpose of this paper is to provide an overview of SAA system development in general, as well as the current challenges facing UAV researchers and designers.

  11. First experimental results with the Current Limit Avoidance System at the JET tokamak

    Energy Technology Data Exchange (ETDEWEB)

    De Tommasi, G. [Associazione EURATOM-ENEA-CREATE, Università di Napoli Federico II, Via Claudio 21, 80125 Napoli (Italy); Galeani, S. [Dipartimento di Informatica, Sistemi e Produzione, Università di Roma, Tor Vergata, Rome (Italy); Jachmich, S. [Association EURATOM-Belgian State, Koninklijke Militaire School - Ecole Royale Militaire, B-1000 Brussels (Belgium); Joffrin, E. [IRFM-CEA, Centre de Cadarache, 13108 Saint-paul-lez-Durance (France); Lennholm, M. [EFDA Close Support Unit, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); European Commission, B-1049 Brussels (Belgium); Lomas, P.J. [Euratom-CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Neto, A.C. [Associazione EURATOM-IST, Instituto de Plasmas e Fusao Nuclear, IST, 1049-001 Lisboa (Portugal); Maviglia, F. [Associazione EURATOM-ENEA-CREATE, Via Claudio 21, 80125 Napoli (Italy); McCullen, P. [Euratom-CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Pironti, A. [Associazione EURATOM-ENEA-CREATE, Università di Napoli Federico II, Via Claudio 21, 80125 Napoli (Italy); Rimini, F.G. [Euratom-CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Sips, A.C.C. [European Commission, B-1049 Brussels (Belgium); Varano, G.; Vitelli, R. [Dipartimento di Informatica, Sistemi e Produzione, Università di Roma, Tor Vergata, Rome (Italy); Zaccarian, L. [CNRS, LAAS, 7 Avenue du Colonel Roche, F-31400 Toulouse (France); Universitè de Toulouse, LAAS, F-31400 Toulouse (France)

    2013-06-15

    The Current Limit Avoidance System (CLA) has been recently deployed at the JET tokamak to avoid current saturations in the poloidal field (PF) coils when the eXtreme Shape Controller is used to control the plasma shape. In order to cope with the current saturation limits, the CLA exploits the redundancy of the PF coils system to automatically obtain almost the same plasma shape using a different combination of currents in the PF coils. In the presence of disturbances it tries to avoid the current saturations by relaxing the constraints on the plasma shape control. The CLA system has been successfully implemented on the JET tokamak and fully commissioned in 2011. This paper presents the first experimental results achieved in 2011–2012 during the restart and the ITER-like wall campaigns at JET.

  12. Seabird mortality induced by land-based artificial lights.

    Science.gov (United States)

    Rodríguez, Airam; Holmes, Nick D; Ryan, Peter G; Wilson, Kerry-Jayne; Faulquier, Lucie; Murillo, Yovana; Raine, André F; Penniman, Jay F; Neves, Verónica; Rodríguez, Beneharo; Negro, Juan J; Chiaradia, André; Dann, Peter; Anderson, Tracy; Metzger, Benjamin; Shirai, Masaki; Deppe, Lorna; Wheeler, Jennifer; Hodum, Peter; Gouveia, Catia; Carmo, Vanda; Carreira, Gilberto P; Delgado-Alburqueque, Luis; Guerra-Correa, Carlos; Couzi, François-Xavier; Travers, Marc; Corre, Matthieu Le

    2017-10-01

    Artificial lights at night cause high mortality of seabirds, one of the most endangered groups of birds globally. Fledglings of burrow-nesting seabirds, and to a lesser extent adults, are attracted to and then grounded (i.e., forced to land) by lights when they fly at night. We reviewed the current state of knowledge of seabird attraction to light to identify information gaps and propose measures to address the problem. Although species in families such as Alcidae and Anatidae can be grounded by artificial light, the most affected seabirds are petrels and shearwaters (Procellariiformes). At least 56 species of Procellariiformes, more than one-third of them (24) threatened, are subject to grounding by lights. Seabirds grounded by lights have been found worldwide, mainly on oceanic islands but also at some continental locations. Petrel breeding grounds confined to formerly uninhabited islands are particularly at risk from light pollution due to tourism and urban sprawl. Where it is impractical to ban external lights, rescue programs of grounded birds offer the most immediate and employed mitigation to reduce the rate of light-induced mortality and save thousands of birds every year. These programs also provide useful information for seabird management. However, these data are typically fragmentary, biased, and uncertain and can lead to inaccurate impact estimates and poor understanding of the phenomenon of seabird attraction to lights. We believe the most urgently needed actions to mitigate and understand light-induced mortality of seabirds are estimation of mortality and effects on populations; determination of threshold light levels and safe distances from light sources; documentation of the fate of rescued birds; improvement of rescue campaigns, particularly in terms of increasing recovery rates and level of care; and research on seabird-friendly lights to reduce attraction. © 2017 Society for Conservation Biology.

  13. Plutonium bioaccumulation in seabirds.

    Science.gov (United States)

    Strumińska-Parulska, Dagmara I; Skwarzec, Bogdan; Fabisiak, Jacek

    2011-12-01

    The aim of the paper was plutonium (²³⁸Pu and ²³⁹⁺²⁴⁰Pu) determination in seabirds, permanently or temporarily living in northern Poland at the Baltic Sea coast. Together 11 marine birds species were examined: 3 species permanently residing in the southern Baltic, 4 species of wintering birds and 3 species of migrating birds. The obtained results indicated plutonium is non-uniformly distributed in organs and tissues of analyzed seabirds. The highest plutonium content was found in the digestion organs and feathers, the smallest in skin and muscles. The plutonium concentration was lower in analyzed species which feed on fish and much higher in herbivorous species. The main source of plutonium in analyzed marine birds was global atmospheric fallout.

  14. Chemical kin label in seabirds

    Science.gov (United States)

    Célérier, Aurélie; Bon, Cécile; Malapert, Aurore; Palmas, Pauline; Bonadonna, Francesco

    2011-01-01

    Chemical signals yield critical socio-ecological information in many animals, such as species, identity, social status or sex, but have been poorly investigated in birds. Recent results showed that chemical signals are used to recognize their nest and partner by some petrel seabirds whose olfactory anatomy is well developed and which possess a life-history propitious to olfactory-mediated behaviours. Here, we investigate whether blue petrels (Halobaena caerulea) produce some chemical labels potentially involved in kin recognition and inbreeding avoidance. To overcome methodological constraints of chemical analysis and field behavioural experiments, we used an indirect behavioural approach, based on mice olfactory abilities in discriminating odours. We showed that mice (i) can detect odour differences between individual petrels, (ii) perceive a high odour similarity between a chick and its parents, and (iii) perceive this similarity only before fledging but not during the nestling developmental stage. Our results confirm the existence of an individual olfactory signature in blue petrels and show for the first time, to our knowledge, that birds may exhibit an olfactory kin label, which may have strong implications for inbreeding avoidance. PMID:21525047

  15. Seabirds as a subsistence and cultural resource in two remote Alaskan communities

    Directory of Open Access Journals (Sweden)

    Rebecca C. Young

    2014-12-01

    Full Text Available Small rural Alaskan communities face many challenges surrounding rapid social and ecological change. The role of local subsistence resources may change over time because of changes in social perception, economic need, and cultural patterns of use. We look at the Bering Sea's Pribilof Islands, comprising two very small communities, and investigate the relationship between the local residents and seabirds as a natural resource. Seabirds may strengthen ties to older ways of life and have potential for future economic opportunities, or modernization may direct interest away from seabirds as a cultural and economic resource. We conducted a survey and interviews of residents of the two Pribilof Island communities, St. Paul and St. George, to assess opinions toward seabirds and harvest levels. Seabirds were generally regarded as important both to individuals and the wider community. However, current levels of subsistence harvest are low, and few people continue to actively harvest or visit seabird colonies. Respondents expressed desire for greater knowledge about seabirds and also concerns about the current economy of the islands and a lack of future development prospects. Despite the challenging economic conditions, the villages retain a strong sense of community and place value on their environment and on seabirds. Surveys indicated an interest in developing eco-tourism based around local resources, including seabirds, as a way to improve the economy.

  16. Ammonia emissions from seabird colonies

    Science.gov (United States)

    Blackall, Trevor D.; Wilson, Linda J.; Theobald, Mark R.; Milford, Celia; Nemitz, Eiko; Bull, Jennifer; Bacon, Philip J.; Hamer, Keith C.; Wanless, Sarah; Sutton, Mark A.

    2007-05-01

    Ammonia emissions were measured from two entire seabird colonies with contrasting species assemblages, to ascertain the ammonia volatilisation potentials among seabird species in relation to their nesting behaviour. Emissions were calculated from downwind plume measurements of ammonia concentration using both inverse dispersion and tracer ratio methods. Measured colony emissions ranged 1-90 kg NH3 hour-1, and equated to 16 and 36% volatilization of excreted nitrogen for colonies dominated by ground/burrow nesting and bare rock nesting birds, respectively. The results were applied in a bioenergetics model with a global seabird database. Seabird colonies are found to represent the largest point sources of ammonia globally (up to ~6 Gg NH3 colony-1 year-1). Moreover the largest emissions occur mainly in remote environments with otherwise low NH3 emissions. These ammonia ``hot spots'' explain significant perturbations of the nitrogen cycle in these regions and add ~20% to oceanic ammonia emissions south of latitude 45°S.

  17. Atlantic Offshore Seabird Dataset Catalog

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Several bureaus within the Department of Interior compiled available information from seabird observation datasets from the Atlantic Outer Continental Shelf into a...

  18. Rock coasts and seabird breeding sites : a common optimization

    Science.gov (United States)

    Marie, Eveillard-Buchoux

    2014-05-01

    The North-West coasts of Europe support a lot of part of Northern hemisphere breeding seabirds. In that context, Scotland has a preponderant place and Brittany has southernmost limit of these species areas, for most of them. Outside the breeding season these species live mainly on the open sea and when they do visit the land to breed, they nest on a specific sites : almost all the time they breed on the rock coasts, often on seacliffs. This specific habitat are defines by geomorphological characteristics which offer special forms of the coast. The forms of rock coasts are originally and different because of several proprieties of geology, of lithology, of structures. Breeding seabird, occupying these sites, reveals, in a new light, the richness of these forms and the originals geographic location of the coastline : seabirds prefer nest in exposed coastline like rock caps, rocky points or islands. Seabirds and rock coasts are research topics in environmental geography since several years. However, these combination studies is a new approach in this field and enlargement in the heritage field allows supplement scientific approach. For example, it show that in most important touristic sites, environmental protection measures focused on landscape, habitat or bird, but much more rarely on rock coasts for these intrinsic values. Indeed, in Brittany or in Scotland, seabirds are often stars species in lot of coastal nature reserves, where they're considered like greater ecological heritage. We could see it in touristic promotion field : bird is everywhere, cliff is mostly kept in the dark, as well in leaflets as in speech visitor's guides - without, for example, as a part of this landscape. In all cases, combination of these two heritages is extremely rare. Yet, this current research illustrates the interest and the issue of development of this comparative approach seabirds / rock coasts for optimization of nature tourism and geotourism.

  19. Seabird Colonies in Western Greenland

    DEFF Research Database (Denmark)

    Boertmann, D.; Mosbech, A.; Falk, K.;

    surveys of seabird colonies are needed, due to a lack of information or because the present information probably is outdated. The most immediate threats to the colonial seabirds in western Greenland during the breeding time is hunting and egging. Oil pollution is a minor threat to-day, but will increase...... if offshore areas with oil potential are explored and developed. Tab. 6 gives an overview of each species sensitivity to oil spills and the capacity to recover, as well as a comparison of the western Greenland population numbers to the North Atlantic population numbers. The most significant western Greenland...

  20. The relationships of seabird assemblages to physical habitat features in Pacific equatorial waters during spring 1984-1991

    Science.gov (United States)

    Ribic, C.A.; Ainley, D.G.

    1997-01-01

    The association of seabird species groups with physical habitat was investigated in the eastern tropical Pacific Ocean, far from any breeding colonies. This avoided birds that commute between colony and feeding habitat, behaviour that confuses associations with specific water types and current systems. Seabirds were counted on duplicate tracks in the eastern tropical Pacific each spring from 1984-1991. On each cruise, seabird habitat was measured on the basis of six factors and focused on three species groups: (A) black-winged petrel and white-winged petrel, (B) Juan Fernandez petrel, wedge-tailed shearwater, and sooty tern, and (C) Leach's storm-petrel and wedge-rumped storm-petrel. Group A was associated with the South Equatorial Current, particularly in cooler waters (median of 26.4??C); both petrel species followed this assemblage association with current. Group B was associated with areas characterized by deep thermoclines (median of 60 m) and low salinities (median of 34.33). Within Group B, two of the three species' responses were consistent with the group pattern; Juan Fernandez petrel differed by occurring more often where thermocline slopes were steep (median of 9.8 deg C m-1). Group C was not associated with any physical habitat variable. This was due to species in the group being associated with different habitats: Leach's storm-petrel with the tropical and equatorial surface water masses and wedge-rumped storm-petrel with waters having shallower thermocline depths (median of 22 m). Overall, two of the three assemblages appeared to be associated with physical habitat during spring with consistency among the species in the group. An association with thermocline depth may indicate that productivity was an important predictor of assemblage presence.

  1. Is current serologic RhD typing of blood donors sufficient for avoiding immunization of recipients?

    DEFF Research Database (Denmark)

    Krog, Grethe Risum; Clausen, Frederik Banch; Berkowicz, Adela

    2011-01-01

    Avoiding immunization with clinically important antibodies is a primary objective in transfusion medicine. Therefore, it is central to identify the extent of D antigens that escape routine RhD typing of blood donors and to improve methodology if necessary.......Avoiding immunization with clinically important antibodies is a primary objective in transfusion medicine. Therefore, it is central to identify the extent of D antigens that escape routine RhD typing of blood donors and to improve methodology if necessary....

  2. How to avoid nephrogenic systemic fibrosis: current guidelines in Europe and the United States

    DEFF Research Database (Denmark)

    Thomsen, Henrik S

    2009-01-01

    Views vary about how to avoid nephrogenic systemic fibrosis (NSF). In Europe, it is contraindicated to use gadodiamide, gadopentetate dimeglumine, and gadovertisamide in patients who have a glomerular filtration rate (GFR) of less than 30 mL/min, and these agents may only be used with caution in ...

  3. Effects of ship traffic on seabirds in offshore waters: implications for marine conservation and spatial planning.

    Science.gov (United States)

    Schwemmer, Philipp; Mendel, Bettina; Sonntag, Nicole; Dierschke, Volker; Garthe, Stefan

    2011-07-01

    Most anthropogenic influences on marine ecosystems, except for river- or terrestrial-borne pollution, involve some sort of vessel activity. Increasing anthropogenic activities mean that many countries are being forced to develop spatial planning schemes, while at the same time implementing conservation sites for sensitive species at sea. The effects of ship traffic on seabirds sensitive to human disturbance are currently too poorly understood to allow for the development of proper planning and conservation guidelines. We therefore used aerial surveys and experimental disturbance to elucidate the effects of passing ships on the distribution patterns, habitat loss, and species-specific flight reactions of birds, as well as the potential for habituation. Loons (Gavia spp.) showed clear avoidance of areas with high shipping intensity. Flush distances of four sea duck species differed significantly, with the longest distances recorded for Common Scoters (Melanitta nigra) and the shortest for Common Eiders (Somateria mollissima). Flush distance was positively related to flock size. Among all the sea duck species studied, the duration of temporary habitat loss was longest for Common Scoters. We found indications of habituation in sea ducks within areas of channeled traffic. However, it is questionable if habituation to free-ranging ships is likely to occur, because of their unpredictable nature. We therefore recommend that spatial planning should aim to channel ship traffic wherever possible to avoid further habitat fragmentation and to allow for habituation, at least in some species. Information on the effects of shipping on other seabird species and during different periods of the year is urgently needed, together with information on the effects of different types of boats, including recreational and fishing vessels.

  4. Modeling Nonresident Seabird Foraging Distributions to Inform Ocean Zoning in Central California.

    Science.gov (United States)

    Studwell, Anna J; Hines, Ellen; Elliott, Meredith L; Howar, Julie; Holzman, Barbara; Nur, Nadav; Jahncke, Jaime

    2017-01-01

    Seabird aggregations at sea have been shown to be associated with concentrations of prey. Previous research identified Central California as a highly used foraging area for seabirds, with locally breeding seabirds foraging close to their colonies on Southeast Farallon Island. Herein, we focus on nonresident (i.e. non-locally breeding) seabird species off of Central California. We hypothesized that high-use foraging areas for nonresident seabirds would be influenced by oceanographic and bathymetric factors and that spatial and temporal distributions would be similar within planktivorous and generalist foraging guilds but would differ between them. With data collected by the Applied California Current Ecosystem Studies (ACCESS) partnership during cruises between April and October from 2004-2013, we developed generalized linear models to identify high-use foraging areas for each of six nonresident seabird species. The four generalist species are Phoebastria nigripes (black-footed albatross), Ardenna griseus (sooty shearwater), Ardenna creatopus (pink-footed shearwater), and Fulmarus glacialis (northern fulmar). The two planktivorous species are Phalaropus lobatus (red-necked phalarope) and Phalaropus fulicarius (red phalarope). Sea surface temperature was significant for generalist species and sea surface salinity was important for planktivorous species. The distance to the 200-m isobath was significant in five of six models, Pacific Decadal Oscillation with a 3-month lag in four models, and sea surface fluorescence, the distance to Cordell Bank, and depth in three models. We did not find statistically significant differences between distributions of individual seabird species within a foraging guild or between guilds, with the exception of the sooty shearwater. Model results for a multi-use seabird foraging area highlighted the continental shelf break, particularly within the vicinity of Cordell Bank, as the highest use areas as did Marxan prioritization. Our

  5. Modeling Nonresident Seabird Foraging Distributions to Inform Ocean Zoning in Central California

    Science.gov (United States)

    Hines, Ellen; Elliott, Meredith L.; Howar, Julie; Holzman, Barbara; Nur, Nadav; Jahncke, Jaime

    2017-01-01

    Seabird aggregations at sea have been shown to be associated with concentrations of prey. Previous research identified Central California as a highly used foraging area for seabirds, with locally breeding seabirds foraging close to their colonies on Southeast Farallon Island. Herein, we focus on nonresident (i.e. non-locally breeding) seabird species off of Central California. We hypothesized that high-use foraging areas for nonresident seabirds would be influenced by oceanographic and bathymetric factors and that spatial and temporal distributions would be similar within planktivorous and generalist foraging guilds but would differ between them. With data collected by the Applied California Current Ecosystem Studies (ACCESS) partnership during cruises between April and October from 2004–2013, we developed generalized linear models to identify high-use foraging areas for each of six nonresident seabird species. The four generalist species are Phoebastria nigripes (black-footed albatross), Ardenna griseus (sooty shearwater), Ardenna creatopus (pink-footed shearwater), and Fulmarus glacialis (northern fulmar). The two planktivorous species are Phalaropus lobatus (red-necked phalarope) and Phalaropus fulicarius (red phalarope). Sea surface temperature was significant for generalist species and sea surface salinity was important for planktivorous species. The distance to the 200-m isobath was significant in five of six models, Pacific Decadal Oscillation with a 3-month lag in four models, and sea surface fluorescence, the distance to Cordell Bank, and depth in three models. We did not find statistically significant differences between distributions of individual seabird species within a foraging guild or between guilds, with the exception of the sooty shearwater. Model results for a multi-use seabird foraging area highlighted the continental shelf break, particularly within the vicinity of Cordell Bank, as the highest use areas as did Marxan prioritization. Our

  6. Effects of invasive rats and burrowing seabirds on seeds and seedlings on New Zealand islands.

    Science.gov (United States)

    Grant-Hoffman, Madeline N; Mulder, Christa P H; Bellingham, Peter J

    2010-04-01

    Rats (Rattus rattus, Rattus norvegicus, Rattus exulans) are important invaders on islands. They alter vegetation indirectly by preying on burrowing seabirds. These seabirds affect vegetation through nutrient inputs from sea to land and physical disturbance through trampling and burrowing. Rats also directly affect vegetation though consumption of seeds and seedlings. Seedling communities on northern New Zealand islands differ in composition and densities among islands which have never been invaded by rats, are currently invaded by rats, or from which rats have been eradicated. We conducted experimental investigations to determine the mechanisms driving these patterns. When the physical disturbance of seabirds was removed, in soils collected from islands and inside exclosures, seedling densities increased with seabird burrow density. For example, seedling densities inside exclosures were 10 times greater than those outside. Thus the negative effects of seabirds on seedlings, by trampling and uprooting, overwhelm the potentially beneficial effects of high levels of seed germination, seedling emergence, and possibly seed production, which result from seed burial and nutrient additions. Potential seedling density was reduced on an island where rats were present, germination of seeds from soils of this island was approximately half that found on other islands, but on this island seedling density inside exclosures was 7 times the density outside. Although the total negative effects of seabirds and rats on seedling densities are similar (reduced seedling density), the differences in mechanisms and life stages affected result in very different filters on the plant community.

  7. Seabird acoustic communication at sea: a new perspective using bio-logging devices.

    Science.gov (United States)

    Thiebault, Andréa; Pistorius, Pierre; Mullers, Ralf; Tremblay, Yann

    2016-08-05

    Most seabirds are very noisy at their breeding colonies, when aggregated in high densities. Calls are used for individual recognition and also emitted during agonistic interactions. When at sea, many seabirds aggregate over patchily distributed resources and may benefit from foraging in groups. Because these aggregations are so common, it raises the question of whether seabirds use acoustic communication when foraging at sea? We deployed video-cameras with built in microphones on 36 Cape gannets (Morus capensis) during the breeding season of 2010-2011 at Bird Island (Algoa Bay, South Africa) to study their foraging behaviour and vocal activity at sea. Group formation was derived from the camera footage. During ~42 h, calls were recorded on 72 occasions from 16 birds. Vocalization exclusively took place in the presence of conspecifics, and mostly in feeding aggregations (81% of the vocalizations). From the observation of the behaviours of birds associated with the emission of calls, we suggest that the calls were emitted to avoid collisions between birds. Our observations show that at least some seabirds use acoustic communication when foraging at sea. These findings open up new perspectives for research on seabirds foraging ecology and their interactions at sea.

  8. Seabird acoustic communication at sea: a new perspective using bio-logging devices

    Science.gov (United States)

    Thiebault, Andréa; Pistorius, Pierre; Mullers, Ralf; Tremblay, Yann

    2016-08-01

    Most seabirds are very noisy at their breeding colonies, when aggregated in high densities. Calls are used for individual recognition and also emitted during agonistic interactions. When at sea, many seabirds aggregate over patchily distributed resources and may benefit from foraging in groups. Because these aggregations are so common, it raises the question of whether seabirds use acoustic communication when foraging at sea? We deployed video-cameras with built in microphones on 36 Cape gannets (Morus capensis) during the breeding season of 2010–2011 at Bird Island (Algoa Bay, South Africa) to study their foraging behaviour and vocal activity at sea. Group formation was derived from the camera footage. During ~42 h, calls were recorded on 72 occasions from 16 birds. Vocalization exclusively took place in the presence of conspecifics, and mostly in feeding aggregations (81% of the vocalizations). From the observation of the behaviours of birds associated with the emission of calls, we suggest that the calls were emitted to avoid collisions between birds. Our observations show that at least some seabirds use acoustic communication when foraging at sea. These findings open up new perspectives for research on seabirds foraging ecology and their interactions at sea.

  9. Monitoring populations of breeding seabirds: Final report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — At Cape Thompson, Alaska, the University of Alaska, mapped locations of census plots during his 1959-61 studies (see Swartz 1966) of the seabird colony there....

  10. Seabird mortality caused by Japanese gillnet fisheries

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The meeting covered three aspects: (1) review of data collected by the Fishery Agency on gillnetting of seabirds, (2) U.S. participation as observers aboard Japanese...

  11. North Pacific Pelagic Seabird Database (NPPSD)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The North Pacific Pelagic Seabird Database (NPPSD) was created in 2005 to consolidate data on the oceanic distribution of marine bird species in the North Pacific....

  12. The role of seabirds of the Iles Eparses as reservoirs and disseminators of parasites and pathogens

    Science.gov (United States)

    McCoy, Karen D.; Dietrich, Muriel; Jaeger, Audrey; Wilkinson, David A.; Bastien, Matthieu; Lagadec, Erwan; Boulinier, Thierry; Pascalis, Hervé; Tortosa, Pablo; Le Corre, Matthieu; Dellagi, Koussay; Lebarbenchon, Camille

    2016-04-01

    The role of birds as reservoirs and disseminators of parasites and pathogens has received much attention over the past several years due to their high vagility. Seabirds are particularly interesting hosts in this respect. In addition to incredible long-distance movements during migration, foraging and prospecting, these birds are long-lived, site faithful and breed in dense aggregations in specific colony locations. These different characteristics can favor both the local maintenance and large-scale dissemination of parasites and pathogens. The Iles Eparses provide breeding and feeding grounds for more than 3 million breeding pairs of seabirds including at least 13 species. Breeding colonies on these islands are relatively undisturbed by human activities and represent natural metapopulations in which seabird population dynamics, movement and dispersal can be studied in relation to that of circulating parasites and pathogens. In this review, we summarize previous knowledge and recently-acquired data on the parasites and pathogens found in association with seabirds of the Iles Eparses. These studies have revealed the presence of a rich diversity of infectious agents (viruses, bacteria and parasites) carried by the birds and/or their local ectoparasites (ticks and louse flies). Many of these agents are widespread and found in other ecosystems confirming a role for seabirds in their large scale dissemination and maintenance. The heterogeneous distribution of parasites and infectious agents among islands and seabird species suggests that relatively independent metacommunities of interacting species may exist within the western Indian Ocean. In this context, we discuss how the patterns and determinants of seabird movements may alter parasite and pathogen circulation. We conclude by outlining key aspects for future research given the baseline data now available and current concerns in eco-epidemiology and biodiversity conservation.

  13. Seabirds and climate: knowledge, pitfalls and opportunities

    Directory of Open Access Journals (Sweden)

    Daniel eOro

    2014-12-01

    Full Text Available As a physical driver of ecosystem functioning, it is not surprising that climate influences seabird demography and population dynamics, generally by affecting food availability. However, if we zoom in ecologically, seabirds are in fact very heterogeneous, ranging in size from very small to very large species (with a difference of more than two orders of magnitude in body weight, from planktivorous forms to predators of large fish and squid, from benthic to pelagic, from species with small foraging ranges to species feeding throughout the whole circumpolar region, and from resident species (at a spatial mesoscale to trans-equatorial migrating seabirds that travel large distances across several oceanographic systems. Due to this high variability and the difficulty in obtaining direct reliable estimates of long-term food availability, global climatic indices have been extensively used in studying seabird demography and population dynamics. However, the use made by researchers of these indices has certain conceptual and methodological pitfalls, which I shall address in this review. Other factors, such as anthropogenic impacts (including oil-spills and interaction with fisheries, may further alter or confound the association between climate and seabird demography. These pitfalls and environmental noise, together with the inability to incorporate resilience, may bias our predictions regarding the future impact of global warming on seabirds, many of which have vulnerable populations.

  14. Oceanographic influences on seabirds and cetaceans of the eastern tropical Pacific: A review

    Science.gov (United States)

    Ballance, Lisa T.; Pitman, Robert L.; Fiedler, Paul C.

    2006-05-01

    This paper is part of a comprehensive review of the oceanography of the eastern tropical Pacific, the oceanic region centered on the eastern Pacific warm pool, but also including the equatorial cold tongue and equatorial current system, and summarizes what is known about oceanographic influences on seabirds and cetaceans there. The eastern tropical Pacific supports on the order of 50 species of seabirds and 30 species of cetaceans as regular residents; these include four endemic species, the world’s largest populations for several others, three endemic sub-species, and a multi-species community that is relatively unique to this ecosystem. Three of the meso-scale physical features of the region are particularly significant to seabirds and cetaceans: the Costa Rica Dome for blue whales and short-beaked common dolphins, the Equatorial Front for planktivorous seabirds, and the countercurrent thermocline ridge for flocking seabirds that associate with mixed-species schools of spotted and spinner dolphins and yellowfin tuna. A few qualitative studies of meso- to macro-scale distribution patterns have indicated that some seabirds and cetaceans have species-specific preferences for surface currents. More common are associations with distinct water masses; these relationships have been quantified for a number of species using several different analytical methods. The mechanisms underlying tropical species-habitat relationships are not well understood, in contrast to a number of higher-latitude systems. This may be due to the fact that physical variables have been used as proxies for prey abundance and distribution in species-habitat research in the eastern tropical Pacific. Though seasonal and interannual patterns tend to be complex, species-habitat relationships appear to remain relatively stable over time, and distribution patterns co-vary with patterns of preferred habitat for a number of species. The interactions between seasonal and interannual variation in

  15. AFSC/REFM: Seabird Necropsy dataset of North Pacific

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The seabird necropsy dataset contains information on seabird specimens that were collected under salvage and scientific collection permits primarily by...

  16. Incidental mortality of seabirds in selected commercial fisheries in Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Fishery-seabird observers monitored the incidental mortality of seabirds between 1989 and 1993 in three groundfish longline, trawl, and pot fisheries in the Bering...

  17. Seabird mortality in the Japanese salmon mothership fishery, summer 1982

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Recent studies have demonstrated a serious conflict between certain kinds of fishing gear, particularly gillnets, and seabirds. A study of seabird mortality in the...

  18. Using seabird habitat modeling to inform marine spatial planning in central California's National Marine Sanctuaries.

    Science.gov (United States)

    McGowan, Jennifer; Hines, Ellen; Elliott, Meredith; Howar, Julie; Dransfield, Andrea; Nur, Nadav; Jahncke, Jaime

    2013-01-01

    Understanding seabird habitat preferences is critical to future wildlife conservation and threat mitigation in California. The objective of this study was to investigate drivers of seabird habitat selection within the Gulf of the Farallones and Cordell Bank National Marine Sanctuaries to identify areas for targeted conservation planning. We used seabird abundance data collected by the Applied California Current Ecosystem Studies Program (ACCESS) from 2004-2011. We used zero-inflated negative binomial regression to model species abundance and distribution as a function of near surface ocean water properties, distances to geographic features and oceanographic climate indices to identify patterns in foraging habitat selection. We evaluated seasonal, inter-annual and species-specific variability of at-sea distributions for the five most abundant seabirds nesting on the Farallon Islands: western gull (Larus occidentalis), common murre (Uria aalge), Cassin's auklet (Ptychorampus aleuticus), rhinoceros auklet (Cerorhinca monocerata) and Brandt's cormorant (Phalacrocorax penicillatus). The waters in the vicinity of Cordell Bank and the continental shelf east of the Farallon Islands emerged as persistent and highly selected foraging areas across all species. Further, we conducted a spatial prioritization exercise to optimize seabird conservation areas with and without considering impacts of current human activities. We explored three conservation scenarios where 10, 30 and 50 percent of highly selected, species-specific foraging areas would be conserved. We compared and contrasted results in relation to existing marine protected areas (MPAs) and the future alternative energy footprint identified by the California Ocean Uses Atlas. Our results show that the majority of highly selected seabird habitat lies outside of state MPAs where threats from shipping, oil spills, and offshore energy development remain. This analysis accentuates the need for innovative marine spatial

  19. Using seabird habitat modeling to inform marine spatial planning in central California's National Marine Sanctuaries.

    Directory of Open Access Journals (Sweden)

    Jennifer McGowan

    Full Text Available Understanding seabird habitat preferences is critical to future wildlife conservation and threat mitigation in California. The objective of this study was to investigate drivers of seabird habitat selection within the Gulf of the Farallones and Cordell Bank National Marine Sanctuaries to identify areas for targeted conservation planning. We used seabird abundance data collected by the Applied California Current Ecosystem Studies Program (ACCESS from 2004-2011. We used zero-inflated negative binomial regression to model species abundance and distribution as a function of near surface ocean water properties, distances to geographic features and oceanographic climate indices to identify patterns in foraging habitat selection. We evaluated seasonal, inter-annual and species-specific variability of at-sea distributions for the five most abundant seabirds nesting on the Farallon Islands: western gull (Larus occidentalis, common murre (Uria aalge, Cassin's auklet (Ptychorampus aleuticus, rhinoceros auklet (Cerorhinca monocerata and Brandt's cormorant (Phalacrocorax penicillatus. The waters in the vicinity of Cordell Bank and the continental shelf east of the Farallon Islands emerged as persistent and highly selected foraging areas across all species. Further, we conducted a spatial prioritization exercise to optimize seabird conservation areas with and without considering impacts of current human activities. We explored three conservation scenarios where 10, 30 and 50 percent of highly selected, species-specific foraging areas would be conserved. We compared and contrasted results in relation to existing marine protected areas (MPAs and the future alternative energy footprint identified by the California Ocean Uses Atlas. Our results show that the majority of highly selected seabird habitat lies outside of state MPAs where threats from shipping, oil spills, and offshore energy development remain. This analysis accentuates the need for innovative marine

  20. Evaluation of the effectiveness of light streamer tori-lines and characteristics of bait attacks by seabirds in the western North Pacific.

    Science.gov (United States)

    Sato, Noriyosi; Ochi, Daisuke; Minami, Hiroshi; Yokawa, Kotaro

    2012-01-01

    To improve the effectiveness of tori-lines it is necessary to evaluate the ability of tori-lines to mitigate seabird bycatch and determine what kind of seabird species gather during line settings, attack the bait and are incidentally caught. We conducted two experiments in the western North Pacific and examined the effectiveness for seabird mitigation of light streamer tori-lines which have no long streamers but many light (short) streamers and are mainly used in the North Pacific area. Firstly, the effectiveness of two different types of tori-line (light streamer (1 m) and long streamer (up to 7 m) tori-line) and of two different colors (yellow and red) of light streamers for seabird bycatch avoidance was evaluated using 567 sets based on data from 20 offshore surface commercial longliners. No significant difference in the bycatch number between the different tori-line types and streamer colors was found. Secondly, we investigated the characteristics of the seabird bycatch in the North Pacific and the effectiveness of three different types of streamers (light, hybrid and modified light types) by detailed observations of seabird attacks using a chartered longline vessel. Although the appearance rate of albatrosses and shearwaters were 40.9% and 27.7%, Laysan albatross was the main seabird species that followed the vessel but shearwaters seldom followed the vessel and did not aggregate during line setting. In all attacks on bait observed during line settings, 81% and 7% were by albatrosses and shearwaters, respectively. In the number of primary attacks by Laysan albatrosses which attacked most aggressively of all seabirds, there were no significant differences among the tori-line types. No individuals of shearwater were caught. The results of both experiments indicated that light streamer tori-lines were as effective as tori-lines with long streamers for mitigating seabird bycatch in the North Pacific.

  1. Evaluation of the effectiveness of light streamer tori-lines and characteristics of bait attacks by seabirds in the western North Pacific.

    Directory of Open Access Journals (Sweden)

    Noriyosi Sato

    Full Text Available To improve the effectiveness of tori-lines it is necessary to evaluate the ability of tori-lines to mitigate seabird bycatch and determine what kind of seabird species gather during line settings, attack the bait and are incidentally caught. We conducted two experiments in the western North Pacific and examined the effectiveness for seabird mitigation of light streamer tori-lines which have no long streamers but many light (short streamers and are mainly used in the North Pacific area. Firstly, the effectiveness of two different types of tori-line (light streamer (1 m and long streamer (up to 7 m tori-line and of two different colors (yellow and red of light streamers for seabird bycatch avoidance was evaluated using 567 sets based on data from 20 offshore surface commercial longliners. No significant difference in the bycatch number between the different tori-line types and streamer colors was found. Secondly, we investigated the characteristics of the seabird bycatch in the North Pacific and the effectiveness of three different types of streamers (light, hybrid and modified light types by detailed observations of seabird attacks using a chartered longline vessel. Although the appearance rate of albatrosses and shearwaters were 40.9% and 27.7%, Laysan albatross was the main seabird species that followed the vessel but shearwaters seldom followed the vessel and did not aggregate during line setting. In all attacks on bait observed during line settings, 81% and 7% were by albatrosses and shearwaters, respectively. In the number of primary attacks by Laysan albatrosses which attacked most aggressively of all seabirds, there were no significant differences among the tori-line types. No individuals of shearwater were caught. The results of both experiments indicated that light streamer tori-lines were as effective as tori-lines with long streamers for mitigating seabird bycatch in the North Pacific.

  2. Worldwide distribution and diversity of seabird ticks: implications for the ecology and epidemiology of tick-borne pathogens.

    Science.gov (United States)

    Dietrich, Muriel; Gómez-Díaz, Elena; McCoy, Karen D

    2011-05-01

    The ubiquity of ticks and their importance in the transmission of pathogens involved in human and livestock diseases are reflected by the growing number of studies focusing on tick ecology and the epidemiology of tick-borne pathogens. Likewise, the involvement of wild birds in dispersing pathogens and their role as reservoir hosts are now well established. However, studies on tick-bird systems have mainly focused on land birds, and the role of seabirds in the ecology and epidemiology of tick-borne pathogens is rarely considered. Seabirds typically have large population sizes, wide geographic distributions, and high mobility, which make them significant potential players in the maintenance and dispersal of disease agents at large spatial scales. They are parasitized by at least 29 tick species found across all biogeographical regions of the world. We know that these seabird-tick systems can harbor a large diversity of pathogens, although detailed studies of this diversity remain scarce. In this article, we review current knowledge on the diversity and global distribution of ticks and tick-borne pathogens associated with seabirds. We discuss the relationship between seabirds, ticks, and their pathogens and examine the interesting characteristics of these relationships from ecological and epidemiological points of view. We also highlight some future research directions required to better understand the evolution of these systems and to assess the potential role of seabirds in the epidemiology of tick-borne pathogens.

  3. Mapping seabird sensitivity to offshore wind farms.

    Science.gov (United States)

    Bradbury, Gareth; Trinder, Mark; Furness, Bob; Banks, Alex N; Caldow, Richard W G; Hume, Duncan

    2014-01-01

    We present a Geographic Information System (GIS) tool, SeaMaST (Seabird Mapping and Sensitivity Tool), to provide evidence on the use of sea areas by seabirds and inshore waterbirds in English territorial waters, mapping their relative sensitivity to offshore wind farms. SeaMaST is a freely available evidence source for use by all connected to the offshore wind industry and will assist statutory agencies in assessing potential risks to seabird populations from planned developments. Data were compiled from offshore boat and aerial observer surveys spanning the period 1979-2012. The data were analysed using distance analysis and Density Surface Modelling to produce predicted bird densities across a grid covering English territorial waters at a resolution of 3 km×3 km. Coefficients of Variation were estimated for each grid cell density, as an indication of confidence in predictions. Offshore wind farm sensitivity scores were compiled for seabird species using English territorial waters. The comparative risks to each species of collision with turbines and displacement from operational turbines were reviewed and scored separately, and the scores were multiplied by the bird density estimates to produce relative sensitivity maps. The sensitivity maps reflected well the amassed distributions of the most sensitive species. SeaMaST is an important new tool for assessing potential impacts on seabird populations from offshore development at a time when multiple large areas of development are proposed which overlap with many seabird species' ranges. It will inform marine spatial planning as well as identifying priority areas of sea usage by marine birds. Example SeaMaST outputs are presented.

  4. Mapping Seabird Sensitivity to Offshore Wind Farms

    Science.gov (United States)

    Bradbury, Gareth; Trinder, Mark; Furness, Bob; Banks, Alex N.; Caldow, Richard W. G.; Hume, Duncan

    2014-01-01

    We present a Geographic Information System (GIS) tool, SeaMaST (Seabird Mapping and Sensitivity Tool), to provide evidence on the use of sea areas by seabirds and inshore waterbirds in English territorial waters, mapping their relative sensitivity to offshore wind farms. SeaMaST is a freely available evidence source for use by all connected to the offshore wind industry and will assist statutory agencies in assessing potential risks to seabird populations from planned developments. Data were compiled from offshore boat and aerial observer surveys spanning the period 1979–2012. The data were analysed using distance analysis and Density Surface Modelling to produce predicted bird densities across a grid covering English territorial waters at a resolution of 3 km×3 km. Coefficients of Variation were estimated for each grid cell density, as an indication of confidence in predictions. Offshore wind farm sensitivity scores were compiled for seabird species using English territorial waters. The comparative risks to each species of collision with turbines and displacement from operational turbines were reviewed and scored separately, and the scores were multiplied by the bird density estimates to produce relative sensitivity maps. The sensitivity maps reflected well the amassed distributions of the most sensitive species. SeaMaST is an important new tool for assessing potential impacts on seabird populations from offshore development at a time when multiple large areas of development are proposed which overlap with many seabird species’ ranges. It will inform marine spatial planning as well as identifying priority areas of sea usage by marine birds. Example SeaMaST outputs are presented. PMID:25210739

  5. Mapping seabird sensitivity to offshore wind farms.

    Directory of Open Access Journals (Sweden)

    Gareth Bradbury

    Full Text Available We present a Geographic Information System (GIS tool, SeaMaST (Seabird Mapping and Sensitivity Tool, to provide evidence on the use of sea areas by seabirds and inshore waterbirds in English territorial waters, mapping their relative sensitivity to offshore wind farms. SeaMaST is a freely available evidence source for use by all connected to the offshore wind industry and will assist statutory agencies in assessing potential risks to seabird populations from planned developments. Data were compiled from offshore boat and aerial observer surveys spanning the period 1979-2012. The data were analysed using distance analysis and Density Surface Modelling to produce predicted bird densities across a grid covering English territorial waters at a resolution of 3 km×3 km. Coefficients of Variation were estimated for each grid cell density, as an indication of confidence in predictions. Offshore wind farm sensitivity scores were compiled for seabird species using English territorial waters. The comparative risks to each species of collision with turbines and displacement from operational turbines were reviewed and scored separately, and the scores were multiplied by the bird density estimates to produce relative sensitivity maps. The sensitivity maps reflected well the amassed distributions of the most sensitive species. SeaMaST is an important new tool for assessing potential impacts on seabird populations from offshore development at a time when multiple large areas of development are proposed which overlap with many seabird species' ranges. It will inform marine spatial planning as well as identifying priority areas of sea usage by marine birds. Example SeaMaST outputs are presented.

  6. Preliminary catalog of seabird colonies and photographic mapping of seabird colonies: Annual report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This preliminary catalog identifies 339 seabird colonies lying along the North Pacific coast of Alaska between Cape Fairweather and Unimak Pass. Information is given...

  7. Seabird Nesting Colonies in Louisiana, Geographic NAD83, LSU (1997) [seabirds_LSU_1997

    Data.gov (United States)

    Louisiana Geographic Information Center — This is a point dataset for seabird nesting colonies derived from GPS locations in the field. The attributes of the habitat points are based upon visual assessment...

  8. Oceanographic gradients and seabird prey community dynamics in glacial fjords

    Science.gov (United States)

    Arimitsu, Mayumi L.; Piatt, John F.; Madison, Erica N.; Conaway, Jeff; Hillgruber, N.

    2012-01-01

    Glacial fjord habitats are undergoing rapid change as a result of contemporary global warming, yet little is known about how glaciers influence marine ecosystems. These ecosystems provide important feeding, breeding and rearing grounds for a wide variety of marine organisms, including seabirds of management concern. To characterize ocean conditions and marine food webs near tidewater glaciers, we conducted monthly surveys of oceanographic variables, plankton, fish and seabirds in Kenai Fjords, Alaska, from June to August of 2007 and 2008. We also measured tidal current velocities near glacial features. We found high sediment load from glacial river runoff played a major role in structuring the fjord marine ecosystem. Submerged moraines (sills) isolated cool, fresh, stratified and silt-laden inner fjord habitats from oceanic influence. Near tidewater glaciers, surface layers of turbid glacial runoff limited availability of light to phytoplankton, but macrozooplankton were abundant in surface waters, perhaps due to the absence of a photic cue for diel migration. Fish and zooplankton community structure varied along an increasing temperature gradient throughout the summer. Acoustic measurements indicated that low density patches of fish and zooplankton were available in the surface waters near glacial river outflows. This is the foraging habitat occupied most by Kittlitz's murrelet (Brachyramphus brevirostris), a rare seabird that appears to be specialized for life in glacially influenced environments. Kittlitz's murrelets were associated with floating glacial ice, and they were more likely to occur near glaciers, in deeper water, and in areas with high acoustic backscatter. Kittlitz's murrelet at-sea distribution was limited to areas influenced by turbid glacial outflows, and where prey was concentrated near the surface in waters with low light penetration. Tidewater glaciers impart unique hydrographic characteristics that influence marine plankton and fish

  9. Seabird metapopulations: searching for alternative breeding habitats

    NARCIS (Netherlands)

    Schippers, P.; Snep, R.P.H.; Schotman, A.G.M.; Jochem, R.; Stienen, E.W.M.; Slim, P.A.

    2009-01-01

    Today, many seabird species nest in port areas, which are also necessary for human economic activity. In this paper, we evaluate, using a metapopulation model, the possibilities for creating alternative breeding sites for the Common Tern (Sterna hirundo) in the Rhine¿Meuse¿Scheldt estuary. We explor

  10. Masterplan Wind - Seabirds Cruise Report January 2011

    NARCIS (Netherlands)

    Witte, R.H.; Witte, L.

    2011-01-01

    This cruise report presents the seabird and marine mammal data collected during the 10th ‘fish egg and fish larvae’ survey on the Dutch Continental Shelf, in a series of 12 monthly surveys from April 2010 till March 2011.

  11. Does Croatia Need a General Anti-Avoidance Rule? Recommended Changes to Croatia’s Current Legislative Framework

    Directory of Open Access Journals (Sweden)

    Rebecca Prebble

    2005-09-01

    Full Text Available This paper considers whether Croatia would benefit from the introduction of a general anti-avoidance rule into its tax system. The paper gives an overview of what tax avoidance is and differentiates the concept from the related concepts of tax evasion and fraud. The paper then describes how general anti-avoidance rules work. The paper gives an overview of Croatia’s tax system, including the measures the country already has to combat tax avoidance, and concludes that a general anti-avoidance rule is necessary. The paper draws on the experiences of countries with legal systems similar to that of Croatia to suggest the form that a Croatian general anti-avoidance rule should take.

  12. Colony Foundation in an Oceanic Seabird.

    Directory of Open Access Journals (Sweden)

    Ignacio Munilla

    Full Text Available Seabirds are colonial vertebrates that despite their great potential for long-range dispersal and colonization are reluctant to establish in novel locations, often recruiting close to their natal colony. The foundation of colonies is therefore a rare event in most seabird species and little is known about the colonization process in this group. The Cory's shearwater (Calonectris diomedea is a pelagic seabird that has recently established three new colonies in Galicia (NE Atlantic thus expanding its distribution range 500 km northwards. This study aimed to describe the establishment and early progress of the new Galician populations and to determine the genetic and morphometric characteristics of the individuals participating in these foundation events. Using 10 microsatellite loci, we tested the predictions supported by different seabird colonization models. Possibly three groups of non-breeders, adding up to around 200 birds, started visiting the Galician colonies in the mid 2000's and some of them eventually laid eggs and reproduced, thus establishing new breeding colonies. The Galician populations showed a high genetic diversity and a frequency of private alleles similar to or even higher than some of the large historical populations. Most individuals were assigned to several Atlantic populations and a few (if any to Mediterranean colonies. Our study suggests that a large and admixed population is settling in Galicia, in agreement with predictions from island metapopulation models of colonization. Multiple source colonies imply that some birds colonizing Galicia were dispersing from very distant colonies (> 1500 km. Long-distance colonizations undertaken by relatively large and admixed groups of colonizers can help to explain the low levels of genetic structure over vast areas that are characteristic of most oceanic seabird species.

  13. Marine wind farms and seabirds. Updated national screening of potential conflict areas; Offshore vindenergianlegg og sjoefugl. Oppdatert screening av potensielle konfliktomraader paa nasjonal skala

    Energy Technology Data Exchange (ETDEWEB)

    Christensen-Dalsgaard, Signe; Lorentsen, Svein-Haakon; Hanssen, Frank; Systad, Geir Helge

    2011-07-01

    In 2010 NINA performed a screening of areas that may be suitable for the establishment of offshore wind power plants (Christensen-Dalsgaard et al. 2010). The surveyed area ranged from the Swedish border in the south (North Sea/Skagerrak) to the northern tip of Andoeya (Norwegian Sea). Following the publishing of the report the Directorate for Nature management wanted to extend the analysis so that it also covered the Barents Sea (National scale). While the 2010-report also included potential effects on white-tailed eagles, Eurasian eagle owl and waders this geographically extended analysis only covers seabirds. Marine wind farms are a relatively new element in European waters, and at present there have been few investigations carried out to study their short- and long-term environmental effects. While there have been several studies to identify environmental impacts of wind farms in other countries, there is currently only one such study in Norway, on the island of Smoela. So far, four mechanisms have been emphasized with regard to the impact of wind farms on birds: 1) mortality resulting from collisions with wind turbines (tower and wings), 2) avoidance due to interference from installations in operation and from the activity associated with the construction of wind farms; 3) loss and change of habitat, through habitat degradation and fragmentation, and 4) barrier effects, which may increase the flight distance and increase the birds' energy demands. In this report, we have chosen to use a methodology that was developed to evaluate seabird vulnerability to marine wind farms in German waters. This method provides a species-specific vulnerability index (SSI) based on nine factors: flight maneuverability, flight altitude, percentage of time flying, nocturnal flight activity, sensitivity towards disturbance by ship/helicopter traffic, flexibility in habitat use, bio geographical population size, adult survival rate and conservation status. In addition we added a

  14. Modelling seabird collision risk with off-shore wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Mateos, Maria; Arroyo, Gonzalo Munoz; Rosario, Jose Juan Alonso del

    2011-07-01

    Full text: Recent concern about the adverse effects of collision mortality of avian migrants at wind farms has highlighted the need to understand bird-wind turbine interactions. Here, a stochastic collision model, based on data of seabird behaviour collected on- site, is presented, as a flexible and easy to take tool to assess the collisions probabilities of off-shore wind farms in a pre-construction phase. The collision prediction model considering the wind farm area as a risk window has been constructed as a stochastic model for avian migrants, based on Monte Carlo simulation. The model calculates the probable number of birds collided per time unit. Migration volume, wind farm dimensions, vertical and horizontal distribution of the migratory passage, flight direction and avoidance rates, between other variables, are taken into account in different steps of the model as the input variables. In order to assess the weighted importance of these factors on collision probability predictions, collision probabilities obtained from the set of scenarios resulting from the different combinations of the input variables were modelled by using Generalised Additive Models. The application of this model to a hypothetical project for erecting a wind farm at the Strait of Gibraltar showed that collision probability, and consequently mortality rates, strongly depend on the values of the avoidance rates taken into account, and the distribution of birds into the different altitude layers. These parameters should be considered as priorities to be addressed in post-construction studies. (Author)

  15. Investigating kleptothermy: a reptile-seabird association with thermal benefits.

    Science.gov (United States)

    Corkery, Ilse; Bell, Ben D; Nelson, Nicola J

    2014-01-01

    Studies on interspecific interactions between vertebrates based on thermal benefits are poorly represented in the literature. Ecologists know little about a category of thermoregulation termed kleptothermy. We provide evidence that a close association between a medium-sized reptile (tuatara, Sphenodon punctatus) and a small seabird (fairy prion, Pachyptila turtur) enables the reptile to maintain higher-than-average body temperatures. This is the first multiyear data set to reveal that the presence of an endotherm within a burrow has direct, transferable thermal benefits to an ectotherm. It is possible that such positive interspecific interactions may alleviate thermal stress across the range of a single species. Currently, we know little about the evolutionary consequences of such interactions, and future work should focus on whether these thermal benefits increase fitness through increased growth rates or reproductive output.

  16. Contrasted structuring effects of mesoscale features on the seabird community in the Mozambique Channel

    Science.gov (United States)

    Jaquemet, S.; Ternon, J. F.; Kaehler, S.; Thiebot, J. B.; Dyer, B.; Bemanaja, E.; Marteau, C.; Le Corre, M.

    2014-02-01

    The Mozambique Channel (western Indian Ocean) is a dynamic environment characterised by strong mesoscale features, which influence all biological components of the pelagic ecosystem. We investigated the distribution, abundance and feeding behaviour of seabirds in the Mozambique Channel in relation to physical and biological environmental variables, with a specific interest in mesoscale features. Seabird censuses were conducted in summer and winter during 7 cruises in the southern and northern Mozambique Channel. Tropical species accounted for 49% of the 37 species identified and 97% of the individuals, and species from the sub-Antarctic region constituted 30% of the identifications. The typically tropical sooty tern (Onychoprion fuscata) was the dominant species during all cruises, and overall accounted for 74% of the species observations and 85% of counted birds. Outputs of Generalised Linear Models at the scale of the Mozambique Channel suggested that higher densities of flying and feeding birds occurred in areas with lower sea surface temperatures and lower surface chlorophyll a concentrations. Most of the flocks of feeding birds did not associate with surface schools of fish or marine mammals, but when they did, these flocks were larger, especially when associated with tuna. While tropical species seemed to favour cyclonic eddies, frontal and divergence zones, non-tropical species were more frequently recorded over shelf waters. Sooty terns foraged preferentially in cyclonic eddies where zooplankton, micronekton and tuna schools were abundant. Among other major tropical species, frigatebirds (Fregata spp.) predominated in frontal zones between eddies, where tuna schools also frequently occurred and where geostrophic currents were the strongest. Red-footed boobies (Sula sula) concentrated in divergence zones characterised by low sea level anomalies, low geostrophic currents, and high zooplankton biomass close to the surface. Our results highlight the importance

  17. The global distribution of ammonia emissions from seabird colonies

    Science.gov (United States)

    Riddick, S. N.; Dragosits, U.; Blackall, T. D.; Daunt, F.; Wanless, S.; Sutton, M. A.

    2012-08-01

    Seabird colonies represent a significant source of atmospheric ammonia (NH3) in remote maritime systems, producing a source of nitrogen that may encourage plant growth, alter terrestrial plant community composition and affect the surrounding marine ecosystem. To investigate seabird NH3 emissions on a global scale, we developed a contemporary seabird database including a total seabird population of 261 million breeding pairs. We used this in conjunction with a bioenergetics model to estimate the mass of nitrogen excreted by all seabirds at each breeding colony. The results combined with the findings of mid-latitude field studies of volatilization rates estimate the global distribution of NH3 emissions from seabird colonies on an annual basis. The largest uncertainty in our emission estimate concerns the potential temperature dependence of NH3 emission. To investigate this we calculated and compared temperature independent emission estimates with a maximum feasible temperature dependent emission, based on the thermodynamic dissociation and solubility equilibria. Using the temperature independent approach, we estimate global NH3 emissions from seabird colonies at 404 Gg NH3 per year. By comparison, since most seabirds are located in relatively cold circumpolar locations, the thermodynamically dependent estimate is 136 Gg NH3 per year. Actual global emissions are expected to be within these bounds, as other factors, such as non-linear interactions with water availability and surface infiltration, moderate the theoretical temperature response. Combining sources of error from temperature (±49%), seabird population estimates (±36%), variation in diet composition (±23%) and non-breeder attendance (±13%), gives a mid estimate with an overall uncertainty range of NH3 emission from seabird colonies of 270 [97-442] Gg NH3 per year. These emissions are environmentally relevant as they primarily occur as "hot-spots" in otherwise pristine environments with low anthropogenic

  18. Seasonality in marine ecosystems: Peruvian seabirds, anchovy, and oceanographic conditions.

    Science.gov (United States)

    Passuni, Giannina; Barbraud, Christophe; Chaigneau, Alexis; Demarcq, Hervé; Ledesma, Jesus; Bertrand, Arnaud; Castillo, Ramiro; Perea, Angel; Mori, Julio; Viblanc, Vincent A; Torres-MaitaA, Jose; Bertrand, Sophie

    2016-01-01

    In fluctuating environments, matching breeding timing to periods of high resource availability is crucial for the fitness of many vertebrate species, and may have major consequences on population health. Yet, our understanding of the proximate environmental cues driving seasonal breeding is limited. This is particularly the case in marine ecosystems, where key environmental factors and prey abundance and availability are seldom quantified. The Northern Humboldt Current System (NHCS) is a highly productive, low-latitude ecosystem of moderate seasonality. In this ecosystem, three tropical seabird species (the Guanay Cormorant Phalacrocorax bougainvillii, the Peruvian Booby Sula variegata, and the Peruvian Pelican Pelecanus thagus) live in sympatry and prey almost exclusively on anchovy, Engraulis ringens. From January 2003 to December 2012, we monitored 31 breeding sites along the Peruvian coast to investigate the breeding cycle of these species. We tested for relationships between breeding timing, oceanographic conditions, and prey availability using occupancy models. We found that all three seabird species exhibited seasonal breeding patterns, with marked interspecific differences. Whereas breeding mainly started during the austral winter/early spring and ended in summer/early fall, this pattern was stronger in boobies and pelicans than in cormorants. Breeding onset mainly occurred when upwelling was intense but ecosystem productivity was below its annual maxima, and when anchovy were less available and in poor physiological condition. Conversely, the abundance and availability of anchovy improved during chick rearing and peaked around the time of fledging. These results suggest that breeding timing is adjusted so that fledging may occur under optimal environmental conditions, rather than being constrained by nutritional requirements during egg laying. Adjusting breeding time so that fledglings meet optimal conditions at independence is unique compared with other

  19. Effects of changes in sandeel availability on the reproductive output of seabirds

    DEFF Research Database (Denmark)

    Rindorf, Anna; Wanless, S.; Harris, M.P.

    2000-01-01

    The lesser sandeel Ammodytes marinus is a key prey species for many marine birds in the North Sea. This fish is currently the target of the largest single species fishery in the area, and this has led to concern about the potential impact of the fishery on seabirds. There are 2 critical issues......: does the breeding success of seabirds depend on sandeel availability and does the fishery reduce sandeel availability to a level at which avian reproductive output is affected? This paper investigates the first question in detail and briefly touches on the second by testing for correlations between...... per unit effort statistics from the Danish sandeel fishery. Breeding success in all 3 species was significantly reduced when sandeel availability to the fishery in June was low. There was also evidence that the timing of peak sandeel availability influenced reproductive output such that success...

  20. Update on eating disorders: current perspectives on avoidant/restrictive food intake disorder in children and youth

    Directory of Open Access Journals (Sweden)

    Norris ML

    2016-01-01

    Full Text Available Mark L Norris,1 Wendy J Spettigue,2 Debra K Katzman3 1Division of Adolescent Medicine, Department of Pediatrics, Children’s Hospital of Eastern Ontario, University of Ottawa, Ottawa, ON, Canada; 2Department of Psychiatry, Children’s Hospital of Eastern Ontario, University of Ottawa, Ottawa, ON, Canada; 3Division of Adolescent Medicine, Department of Pediatrics, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada Abstract: Avoidant/restrictive food intake disorder (ARFID is a new eating disorder diagnosis that was introduced in the Diagnostic and Statistical Manual of Mental Disorders (DSM fifth edition. The fourth edition of the DSM had failed to adequately capture a cohort of children, adolescents, and adults who are unable to meet appropriate nutritional and/or energy needs, for reasons other than drive for thinness, leading to significant medical and/or psychological sequelae. With the introduction of ARFID, researchers are now starting to better understand the presentation, clinical characteristics, and complexities of this disorder. This article outlines the diagnostic criteria for ARFID with specific focus on children and youth. A case example of a patient with ARFID, factors that differentiate ARFID from picky eating, and the estimated prevalence in pediatric populations are discussed, as well as clinical and treatment challenges that impact health care providers providing treatment for patients. Keywords: avoidant/restrictive food intake disorder, ARFID, eating disorder, picky eating, prevalence, treatment

  1. The biogeography of globally threatened seabirds and island conservation opportunities.

    Science.gov (United States)

    Spatz, Dena R; Newton, Kelly M; Heinz, Reina; Tershy, Bernie; Holmes, Nick D; Butchart, Stuart H M; Croll, Donald A

    2014-10-01

    Seabirds are the most threatened group of marine animals; 29% of species are at some risk of extinction. Significant threats to seabirds occur on islands where they breed, but in many cases, effective island conservation can mitigate these threats. To guide island-based seabird conservation actions, we identified all islands with extant or extirpated populations of the 98 globally threatened seabird species, as recognized on the International Union for Conservation of Nature Red List, and quantified the presence of threatening invasive species, protected areas, and human populations. We matched these results with island attributes to highlight feasible island conservation opportunities. We identified 1362 threatened breeding seabird populations on 968 islands. On 803 (83%) of these islands, we identified threatening invasive species (20%), incomplete protected area coverage (23%), or both (40%). Most islands with threatened seabirds are amenable to island-wide conservation action because they are small (57% were <1 km(2) ), uninhabited (74%), and occur in high- or middle-income countries (96%). Collectively these attributes make islands with threatened seabirds a rare opportunity for effective conservation at scale. © 2014 Society for Conservation Biology.

  2. Is current serologic RhD typing of blood donors sufficient for avoiding immunization of recipients? (CME)

    DEFF Research Database (Denmark)

    Krog, Grethe Risum; Clausen, Frederik Banch; Berkowicz, Adela

    2011-01-01

    BACKGROUND: Avoiding immunization with clinically important antibodies is a primary objective in transfusion medicine. Therefore, it is central to identify the extent of D antigens that escape routine RhD typing of blood donors and to improve methodology if necessary. STUDY DESIGN AND METHODS: We......-specific primers. Lookback was performed on all recipients of RBCs from RHD+ donors. RESULTS: We found 13 RHD+ samples (0.26%). No variants or chimeras were found. Characterization of DNA revealed a novel DEL type (IVS2-2 A>G). In the lookback of the 136 transfusions with subsequent antibody follow-up, of which 13...... were from DEL donors, one recipient developed anti-D. However, in this case, a competing and more likely cause of immunization was the concurrent transfusion of D+ platelets. Eleven recipients were immunized with 13 antibodies different from anti-D, of which five were anti-K. CONCLUSION: In our...

  3. [Proposal] Legacy seabird monitoring data inventory, compilation, and standardization

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Population data on seabirds are essential for conservation of those species, and are widely used as indicators of change in marine ecosystems. Alaska Maritime,...

  4. Effects of oil and oil burn residues on seabird feathers

    DEFF Research Database (Denmark)

    Fritt-Rasmussen, Janne; Linnebjerg, Jannie Fries; Sørensen, Martin X.

    2016-01-01

    It is well known, that in case of oil spill, seabirds are among the groups of animals most vulnerable. Even small amounts of oil can have lethal effects by destroying the waterproofing of their plumage, leading to loss of insulation and buoyancy. In the Arctic these impacts are intensified....... To protect seabirds, a rapid removal of oil is crucial and in situ burning could be an efficient method. In the present work exposure effects of oil and burn residue in different doses was studied on seabird feathers from legally hunted Common eider (Somateria mollissima) by examining changes in total weight...... of the feather and damages on the microstructure (Amalgamation Index) of the feathers before and after exposure. The results of the experiments indicate that burn residues from in situ burning of an oil spill have similar or larger fouling and damaging effects on seabird feathers, as compared to fresh oil....

  5. Effects of oil and oil burn residues on seabird feathers.

    Science.gov (United States)

    Fritt-Rasmussen, Janne; Linnebjerg, Jannie Fries; Sørensen, Martin X; Brogaard, Nicholas L; Rigét, Frank F; Kristensen, Paneeraq; Jomaas, Grunde; Boertmann, David M; Wegeberg, Susse; Gustavson, Kim

    2016-08-15

    It is well known, that in case of oil spill, seabirds are among the groups of animals most vulnerable. Even small amounts of oil can have lethal effects by destroying the waterproofing of their plumage, leading to loss of insulation and buoyancy. In the Arctic these impacts are intensified. To protect seabirds, a rapid removal of oil is crucial and in situ burning could be an efficient method. In the present work exposure effects of oil and burn residue in different doses was studied on seabird feathers from legally hunted Common eider (Somateria mollissima) by examining changes in total weight of the feather and damages on the microstructure (Amalgamation Index) of the feathers before and after exposure. The results of the experiments indicate that burn residues from in situ burning of an oil spill have similar or larger fouling and damaging effects on seabird feathers, as compared to fresh oil.

  6. Mercury levels in seabirds in the Gulf of Maine

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We conducted a pilot study to screen mercury (Hg) levels in Gulf of Maine seabirds in an effort to determine which species are most at risk, are the most appropriate...

  7. Genetically diverse herpesviruses in South American Atlantic coast seabirds

    Science.gov (United States)

    Favero, Cíntia Maria; Shivaprasad, H. L.; Uhart, Marcela; Musso, Cesar Meyer; Rago, María Virginia; Silva-Filho, Rodolfo Pinho; Canabarro, Paula Lima; Craig, María Isabel; Olivera, Valeria; Pereda, Ariel; Brandão, Paulo Eduardo; Catão-Dias, José Luiz

    2017-01-01

    Different herpesviruses have been associated with respiratory and enteric disease and mortality among seabirds and waterfowl. In 2011, a respiratory disease outbreak affected 58.3% (98/168) of the Magellanic penguins undergoing rehabilitation due to an oil spill off the southern Brazilian coast. Etiology was attributed to a novel herpesvirus identified by histopathology, immunohistochemistry, electron microscopy and molecular studies with partial DNA sequencing. Since migration, rehabilitation and translocation may facilitate the spread of pathogens between populations and trigger the onset of clinical disease in animals with latent infections, investigation of herpesvirus occurrence in asymptomatic seabirds was performed. Samples from free-ranging seabirds were collected in Argentinian Patagonia (Magellanic penguins) and the Abrolhos Archipelago in Brazil (Brown boobies, Masked boobies, Red-billed tropicbirds, White-tailed tropicbirds and South American tern). Furthermore, asymptomatic seabirds housed at the facility where the outbreak occurred were also sampled. In total, 354 samples from eight seabird species were analyzed by PCR for herpesvirus. Four different sequences of herpesviruses were identified, one in Yellow-nosed Albatross, one in Boobies and Tropicbirds and two in Magellanic penguins. Magellanic penguin herpesvirus 1 was identified during the penguin outbreak at the rehabilitation facility in Brazil, while Magellanic penguin herpesvirus 2 was recovered from free-ranging penguins at four reproduction sites in Argentina. Phylogenic analysis of the herpesviruses sequences tentatively identified suggested that the one found in Suliformes and the one associated with the outbreak are related to sequences of viruses that have previously caused seabird die-offs. These findings reinforce the necessity for seabird disease surveillance programs overall, and particularly highlight the importance of quarantine, good hygiene, stress management and pre

  8. LightForce photon-pressure collision avoidance: Efficiency analysis in the current debris environment and long-term simulation perspective

    Science.gov (United States)

    Yang Yang, Fan; Nelson, Bron; Aziz, Jonathan; Carlino, Roberto; Dono Perez, Andres; Faber, Nicolas; Foster, Cyrus; Frost, Chad; Henze, Chris; Karacalıoğlu, Arif Göktuğ; Levit, Creon; Marshall, William; Mason, James; O'Toole, Conor; Swenson, Jason; Worden, Simon P.; Stupl, Jan

    2016-09-01

    This work provides an efficiency analysis of the LightForce space debris collision avoidance scheme in the current debris environment and describes a simulation approach to assess its impact on the long-term evolution of the space debris environment. LightForce aims to provide just-in-time collision avoidance by utilizing photon pressure from ground-based industrial lasers. These ground stations impart minimal accelerations to increase the miss distance for a predicted conjunction between two objects. In the first part of this paper we will present research that investigates the short-term effect of a few systems consisting of 20 kW class lasers directed by 1.5 m diameter telescopes using adaptive optics. The results found such a network of ground stations to mitigate more than 85 percent of conjunctions and could lower the expected number of collisions in Low Earth Orbit (LEO) by an order of magnitude. While these are impressive numbers that indicate LightForce's utility in the short-term, the remaining 15 % of possible collisions contain (among others) conjunctions between two massive objects that would add large amount of debris if they collide. Still, conjunctions between massive objects and smaller objects can be mitigated. Hence, we choose to expand the capabilities of the simulation software to investigate the overall effect of a network of LightForce stations on the long-term debris evolution. In the second part of this paper, we will present the planned simulation approach for that effort. For the efficiency analysis of collision avoidance in the current debris environment, we utilize a simulation approach that uses the entire Two Line Element (TLE) catalog in LEO for a given day as initial input. These objects are propagated for one year and an all-on-all conjunction analysis is performed. For conjunctions that fall below a range threshold, we calculate the probability of collision and record those values. To assess efficiency, we compare a baseline

  9. AFSC/REFM: Seabird food habits dataset of the North Pacific

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The seabird food habits dataset contains information on the stomach contents from seabird specimens that were collected under salvage and scientific collection...

  10. Dynamics of Seabird Colonies Vulnerable to Sea-Level Rise at French Frigate Shoals, Hawaii

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Globally, seabirds are vulnerable to anthropogenic threats both at sea and on land. Seabirds typically nest colonially and show strong site fidelity; therefore,...

  11. Mortality of seabirds in the Japanese high seas salmon mothership fishery, 1981-1984

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Annual mortality of over 160,000 seabirds in the Japanese mothership fishery is apparently not causing significant harm to seabird populations in the North Pacific....

  12. Washington Maritime NWRC: Initial Survey Instructions for Surface-nesting Seabird Monitoring

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In Region 1, the vast majority of seabirds nest on NWRs. Because seabirds are dependent on the marine environment and surface-nesters are easily observed on...

  13. Temporal variation in atmospheric ammonia concentrations above seabird colonies

    Science.gov (United States)

    Blackall, T. D.; Wilson, L. J.; Bull, J.; Theobald, M. R.; Bacon, P. J.; Hamer, K. C.; Wanless, S.; Sutton, M. A.

    Recent studies have shown that seabirds are an important source of ammonia (NH 3) emissions in remote coastal ecosystems. Nesting behaviour, which varies between seabird species, is likely to be a major factor in determining the proportion of excreted nitrogen (N) volatilised to the atmosphere as NH 3. A long-term NH 3 monitoring programme was implemented at a Scottish seabird colony with a range of species and associated nesting behaviours. The average monthly NH 3 concentration was measured at 12 locations over a 14-month period, to infer spatial (i.e. species-specific) and temporal (seasonal) changes in NH 3 emissions from different seabird species. An emissions model of seabird NH 3, based on species-specific bioenergetics and behaviour, was applied to produce spatial estimates for input to a dispersion model. Atmospheric NH 3 concentrations demonstrated spatial variability as a result of differing local populations of breeding seabirds, with the highest concentrations measured above cliff nesting species such as Common guillemot Uria aalge, Razorbill Alca torda and Black-legged kittiwake Rissa tridactyla. NH 3 concentrations above a colony of burrow nesting Atlantic puffin Fratercula arctica were low, considering the high number of birds. Emission of NH 3 from excreted N exhibits a time lag of approximately a month. It is likely that all excreted N is lost from the colony by volatilisation as NH 3 or surface run-off between breeding seasons. Modelled NH 3 emissions and concentrations correlated with measured concentrations, but were much higher, reflecting uncertainties in the local turbulent characteristics. The results allow multi-species seabird population data to be used for the calculation of regional and global NH 3 emission inventories, whilst improving understanding of N budgets of remote coastal ecosystems.

  14. A catalog of Louisiana's nesting seabird colonies

    Science.gov (United States)

    Fontenot, William R.; Cardiff, Steve W.; DeMay, Richard A.; Dittmann, Donna L.; Hartley, Stephen B.; Jeske, Clinton W.; Lorenz, Nicole; Michot, Thomas C.; Purrington, Robert Dan; Seymour, Michael; Vermillion, William G.

    2012-01-01

    Summarizing his colonial nesting waterbird survey experiences along the northern coast of the Gulf of Mexico in a paper presented to the Colonial Waterbird Group of the Waterbird Society (Portnoy 1978), bird biologist John W. Portnoy stated, “This huge concentration of nesting waterbirds, restricted almost entirely to the wetlands and estuaries of southern Louisiana, is unmatched in all of North America; for example, a 1975 inventory of wading birds along the Atlantic Coast from Maine to Florida [Custer and Osborn, in press], tallied 250,000 breeding [waterbirds] of 14 species, in contrast with the 650,000 birds of 15 species just from Sabine Pass to Mobile Bay.” The “650,000 birds” to which Portnoy referred, were tallied by him in a 1976 survey of coastal Louisiana, Mississippi, and Alabama (see below, under “Major Surveys” section). According to the National Atlas of Coastal Waterbird Colonies in the Contiguous United States: 1976-82 (Spendelow and Patton 1988), the percentages of the total U.S. populations of Laughing Gull (11%), Forster's Tern (52%), Royal Tern (16%), Sandwich Tern (77%), and Black Skimmer (44%) which annually nest in Louisiana are significant – perhaps crucially so in the cases of Forster's Tern, Sandwich Tern, and Black Skimmer. Nearly three decades after Spendelow and Patton's determinations above, coastal Louisiana still stands out as the major center of colonial wading bird and seabird nesting in all of the United States. Within those three intervening decades, however, the

  15. Identification and characterisation of foraging areas of seabirds in upwelling systems: biological and hydrographic implications for foraging at sea

    OpenAIRE

    Ludynia, Katrin

    2007-01-01

    This thesis investigates the foraging behaviour of three seabird species, the African penguin (Spheniscus demersus) and the Cape gannet (Morus capensis) in the Benguela upwelling system as well as the Peruvian booby (Sula variegata) in the Humboldt Current. Biological and hydrographic parameters were considered when evaluating the characteristics of foraging areas and the behaviour of the species studied. Foraging areas used by the birds as well as the birds' diving behaviour were assessed by...

  16. Using stable isotopes of nitrogen and carbon to study seabird ecology: applications in the Mediterranean seabird community

    Directory of Open Access Journals (Sweden)

    Manuela G. Forero

    2003-07-01

    Full Text Available The application of the stable isotope technique to ecological studies is becoming increasingly widespread. In the case of seabirds, stable isotopes of nitrogen and carbon have been mainly used as dietary tracers. This approach relieson the fact that food web isotopic signatures are reflected in the tissues of the consumer. In addition to the study of trophic ecology, stable isotopes have been used to track the movement of seabirds across isotopic gradients, as individuals moving between isotopically distinct foodwebs can carry with them information on the location of previous feeding areas. Studies applying the stable isotope methodology to the study of seabird ecology show a clear evolution from broad and descriptive approaches to detailed and individual-based analyses. The purpose of this article is to show the different fields of application of stable isotopes to the study of the seabird ecology. Finally, we illustrate the utility of this technique by considering the particularities of the Mediterranean seabird community, suggesting different ecological questions and conservation problems that could be addressed by using the stable isotope approach in this community.

  17. Risk Factors for Seabird Bycatch in a Pelagic Longline Tuna Fishery.

    Directory of Open Access Journals (Sweden)

    Eric Gilman

    Full Text Available Capture in global pelagic longline fisheries threatens the viability of some seabird populations. The Hawaii longline tuna fishery annually catches hundreds of seabirds, primarily Laysan (Phoebastria immutabilis and black-footed (P. nigripes albatrosses. Since seabird regulations were introduced in 2001, the seabird catch rate has declined 74%. However, over the past decade, seabird catch levels significantly increased due to significant increasing trends in both effort and nominal seabird catch rates. We modelled observer data using a spatio-temporal generalized additive mixed model with zero-inflated Poisson likelihood to determine the significance of the effect of various risk factors on the seabird catch rate. The seabird catch rate significantly increased as annual mean multivariate ENSO index values increased, suggesting that decreasing ocean productivity observed in recent years in the central north Pacific may have contributed to the increasing trend in nominal seabird catch rate. A significant increasing trend in number of albatrosses attending vessels, possibly linked to declining regional ocean productivity and increasing absolute abundance of black-footed albatrosses, may also have contributed to the increasing nominal seabird catch rate. Largest opportunities for reductions are through augmented efficacy of seabird bycatch mitigation north of 23° N where mitigation methods are required and during setting instead of during hauling. Both side vs. stern setting, and blue-dyed vs. untreated bait significantly reduced the seabird catch rate. Of two options for meeting regulatory requirements, side setting had a significantly lower seabird catch rate than blue-dyed bait. There was significant spatio-temporal and seasonal variation in the risk of seabird capture with highest catch rates in April and May and to the northwest of the main Hawaiian Islands.

  18. Seabird bycatch in pelagic longline fisheries is grossly underestimated when using only haul data.

    Directory of Open Access Journals (Sweden)

    Nigel Brothers

    Full Text Available Hundreds of thousands of seabirds are killed each year as bycatch in longline fisheries. Seabirds are predominantly caught during line setting but bycatch is generally recorded during line hauling, many hours after birds are caught. Bird loss during this interval may lead to inaccurate bycatch information. In this 15 year study, seabird bycatch was recorded during both line setting and line hauling from four fishing regions: Indian Ocean, Southern Ocean, Coral Sea and central Pacific Ocean. Over 43,000 albatrosses, petrels and skuas representing over 25 species were counted during line setting of which almost 6,000 seabirds attempted to take the bait. Bait-taking interactions were placed into one of four categories. (i The majority (57% of bait-taking attempts were "unsuccessful" involving seabirds that did not take the bait nor get caught or hooked. (ii One-third of attempts were "successful" with seabirds removing the bait while not getting caught. (iii One-hundred and seventy-six seabirds (3% of attempts were observed being "caught" during line setting, with three albatross species - Laysan (Phoebastria immutabilis, black-footed (P. nigripes and black-browed (Thalassarche melanophrys- dominating this category. However, of these, only 85 (48% seabird carcasses were retrieved during line hauling. Most caught seabirds were hooked through the bill. (iv The remainder of seabird-bait interactions (7% was not clearly observed, but likely involved more "caught" seabirds. Bait taking attempts and percentage outcome (e.g. successful, caught varied between seabird species and was not always related to species abundance around fishing vessels. Using only haul data to calculate seabird bycatch grossly underestimates actual bycatch levels, with the level of seabird bycatch from pelagic longline fishing possibly double what was previously thought.

  19. Seabird bycatch in pelagic longline fisheries is grossly underestimated when using only haul data.

    Science.gov (United States)

    Brothers, Nigel; Duckworth, Alan R; Safina, Carl; Gilman, Eric L

    2010-08-31

    Hundreds of thousands of seabirds are killed each year as bycatch in longline fisheries. Seabirds are predominantly caught during line setting but bycatch is generally recorded during line hauling, many hours after birds are caught. Bird loss during this interval may lead to inaccurate bycatch information. In this 15 year study, seabird bycatch was recorded during both line setting and line hauling from four fishing regions: Indian Ocean, Southern Ocean, Coral Sea and central Pacific Ocean. Over 43,000 albatrosses, petrels and skuas representing over 25 species were counted during line setting of which almost 6,000 seabirds attempted to take the bait. Bait-taking interactions were placed into one of four categories. (i) The majority (57%) of bait-taking attempts were "unsuccessful" involving seabirds that did not take the bait nor get caught or hooked. (ii) One-third of attempts were "successful" with seabirds removing the bait while not getting caught. (iii) One-hundred and seventy-six seabirds (3% of attempts) were observed being "caught" during line setting, with three albatross species - Laysan (Phoebastria immutabilis), black-footed (P. nigripes) and black-browed (Thalassarche melanophrys)- dominating this category. However, of these, only 85 (48%) seabird carcasses were retrieved during line hauling. Most caught seabirds were hooked through the bill. (iv) The remainder of seabird-bait interactions (7%) was not clearly observed, but likely involved more "caught" seabirds. Bait taking attempts and percentage outcome (e.g. successful, caught) varied between seabird species and was not always related to species abundance around fishing vessels. Using only haul data to calculate seabird bycatch grossly underestimates actual bycatch levels, with the level of seabird bycatch from pelagic longline fishing possibly double what was previously thought.

  20. Drake Passage-Antarctic Peninsula Ecosystem Research: Spring and Fall Zooplankton and Seabird Assemblages

    Science.gov (United States)

    Loeb, V. J.; Chereskin, T. K.; Santora, J. A.

    2016-02-01

    Acoustic Doppler Current Profiler (ADCP) records from multiple "L.M. Gould" supply transits of Drake Passage from 1999 to present demonstrate spatial and temporal (diel, seasonal, annual and longer term) variability in acoustics backscattering. Acoustics backscattering strength in the upper water column corresponds to zooplankton and nekton biomass that relates to seabird and mammal distribution and abundance. Recent results indicate that interannual variability in backscattering strength is correlated to climate indices. The interpretation of these ecological changes is severely limited because the sound scatterers previously had not been identified and linkages to upper trophic level predators are unknown. Net-tows, depth-referenced underwater videography and seabird/mammal visual surveys during spring 2014 and fall 2015 transits provided information on the taxonomic-size composition, distribution, aggregation and behavioral patterns of dominant ADCP backscattering organisms and relate these to higher level predator populations. The distribution and composition of zooplankton species and seabird assemblages conformed to four biogeographic regions. Areas of elevated secondary productivity coincided with increased ADCP target strength with highest concentrations off Patagonia and Antarctic Peninsula and secondary peaks around the Polar Front. Small sized zooplankton taxa dominated north of the Polar Front while larger taxa dominated to the south. Regionally important prey items likely are: copepods, amphipods, small euphausiids and fish (Patagonia); copepods, myctophids, shelled pteropods and squid (Polar Front); large euphausiids (Antarctic Peninsula). This study demonstrates that biological observations during "L.M. Gould" supply transits greatly augment the value of routinely collected ADCP and XBT data and provide basic information relevant to the impacts of climate change in this rapidly warming portion of the Southern Ocean

  1. Determining seabird body condition using nonlethal measures.

    Science.gov (United States)

    Jacobs, Shoshanah R; Elliott, Kyle; Guigueno, Mélanie F; Gaston, Anthony J; Redman, Paula; Speakman, John R; Weber, Jean-Michel

    2012-01-01

    Energy stores are critical for successful breeding, and longitudinal studies require nonlethal methods to measure energy stores ("body condition"). Nonlethal techniques for measuring energy reserves are seldom verified independently. We compare body mass, size-corrected mass (SCM), plasma lipids, and isotopic dilution with extracted total body lipid content in three seabird species (thick-billed murres Uria lomvia, all four measures; northern fulmars Fulmarus glacialis, three measures; and black-legged kittiwakes Rissa tridactyla, two measures). SCM and body mass were better predictors of total body lipids for the species with high percent lipids (fulmars; R2 = 0.5-0.6) than for the species with low percent lipids (murres and kittiwakes; R2 = 0.2-0.4). The relationship between SCM and percent body lipids, which we argue is often a better measure of condition, was also poor (R2 SCM be used as an index of energy stores only when lipids exceed 15% of body mass. Across all three species we measured, SCM based on the ordinary least squares regression of mass on the first principal component outperformed other measures. Isotopic dilution was a better predictor of both total body lipids and percent body lipids than were mass, SCM, or plasma lipids in murres. Total body lipids decreased through the breeding season at both sites, while total and neutral plasma lipid concentrations increased at one site but not another, suggesting mobilization of lipid stores for breeding. A literature review showed substantial variation in the reliability of plasma markers, and we recommend isotopic dilution (oxygen-18, plateau) for determination of energy reserves in birds where lipid content is below 15%.

  2. Celestial moderation of tropical seabird behavior.

    Directory of Open Access Journals (Sweden)

    Patrick Pinet

    Full Text Available Most animals, including birds, have cyclic life histories and numerous studies generally conducted on captive animals have shown that photoperiod is the main factor influencing this periodicity. Moon cycles can also affect periodic behavior of birds. Few studies have investigated the influence of these environmental cues in natural settings, and particularly in tropical areas where the change in photoperiod is slight and some bird species keep cyclic behaviors. Using miniaturized light sensors, we simultaneously investigated under natural conditions the influence of photoperiod and moon phases on the migration dates and at-sea activity of a tropical seabird species, the Barau's petrel, throughout its annual cycle. Firstly, we found that birds consistently started their pre- and post-breeding migrations at precise dates corresponding in both cases to a day-duration of 12.5 hours, suggesting a strong influence of the photoperiod in the regulation of migration behavior. We also found that mean population arrival dates to the colony changed from year to year and they were influenced by moon phases. Returns at their colonies occurred around the last full moon of the austral winter, suggesting that moon cycle is used by birds to synchronize their arrival. Secondly, variations of day-time activity were sinusoidal and correlated to seasonal changes of daylength. We thus hypothesize that the photoperiod could directly affect the behavior of the birds at sea. Night-time at-sea activity exhibited a clear cycle of 29.2 days, suggesting that nocturnal foraging was highly regulated by moon phase, particularly during the non-breeding season. To our knowledge, this is the first study to document a mixed regulation of the behavior of a wild bird by photoperiod and moon phases throughout its annual cycle.

  3. Celestial moderation of tropical seabird behavior.

    Science.gov (United States)

    Pinet, Patrick; Jaeger, Audrey; Cordier, Emmanuel; Potin, Gaël; Le Corre, Matthieu

    2011-01-01

    Most animals, including birds, have cyclic life histories and numerous studies generally conducted on captive animals have shown that photoperiod is the main factor influencing this periodicity. Moon cycles can also affect periodic behavior of birds. Few studies have investigated the influence of these environmental cues in natural settings, and particularly in tropical areas where the change in photoperiod is slight and some bird species keep cyclic behaviors. Using miniaturized light sensors, we simultaneously investigated under natural conditions the influence of photoperiod and moon phases on the migration dates and at-sea activity of a tropical seabird species, the Barau's petrel, throughout its annual cycle. Firstly, we found that birds consistently started their pre- and post-breeding migrations at precise dates corresponding in both cases to a day-duration of 12.5 hours, suggesting a strong influence of the photoperiod in the regulation of migration behavior. We also found that mean population arrival dates to the colony changed from year to year and they were influenced by moon phases. Returns at their colonies occurred around the last full moon of the austral winter, suggesting that moon cycle is used by birds to synchronize their arrival. Secondly, variations of day-time activity were sinusoidal and correlated to seasonal changes of daylength. We thus hypothesize that the photoperiod could directly affect the behavior of the birds at sea. Night-time at-sea activity exhibited a clear cycle of 29.2 days, suggesting that nocturnal foraging was highly regulated by moon phase, particularly during the non-breeding season. To our knowledge, this is the first study to document a mixed regulation of the behavior of a wild bird by photoperiod and moon phases throughout its annual cycle.

  4. LightForce Photon-pressure Collision Avoidance: Efficiency Analysis in the Current Debris Environment and Long-Term Simulation Perspective

    Science.gov (United States)

    Yang, Fan Y.; Nelson, Bron; Carlino, Roberto; Perez, Andres D.; Faber, Nicolas; Henze, Chris; Karacahoglu, Arif G.; O'Toole, Conor; Swenson, Jason; Stupl, Jan

    2015-01-01

    This work provides an efficiency analysis of the LightForce space debris collision avoidance scheme in the current debris environment and describes a simulation approach to assess its impact on the long-term evolution of the space debris environment. LightForce aims to provide just-in-time collision avoidance by utilizing photon pressure from ground-based industrial lasers. These ground stations impart minimal accelerations to increase the miss distance for a predicted conjunction between two objects. In the first part of this paper we will present research that investigates the short-term effect of a few systems consisting of 10kW class lasers directed by 1.5 m diameter telescopes using adaptive optics. The results found such a network of ground stations to mitigate more than 85 percent of conjunctions and could lower the expected number of collisions in Low Earth Orbit (LEO) by an order of magnitude. While these are impressive numbers that indicate LightForce's utility in the short-term, the remaining 15 percent of possible collisions contain (among others) conjunctions between two massive objects that would add large amount of debris if they collide. Still, conjunctions between massive objects and smaller objects can be mitigated. Hence we choose to expand the capabilities of the simulation software to investigate the overall effect of a network of LightForce stations on the long-term debris evolution. In the second part of this paper, we will present the planed simulation approach for that effort.

  5. Seasonal spatial patterns in seabird and marine mammal distribution in the eastern Chukchi and western Beaufort seas: Identifying biologically important pelagic areas

    Science.gov (United States)

    Kuletz, Kathy J.; Ferguson, Megan C.; Hurley, Brendan; Gall, Adrian E.; Labunski, Elizabeth A.; Morgan, Tawna C.

    2015-08-01

    The Chukchi and Beaufort seas are undergoing rapid climate change and increased human activity. Conservation efforts for upper trophic level predators such as seabirds and marine mammals require information on species' distributions and identification of important marine areas. Here we describe broad-scale distributions of seabirds and marine mammals. We examined spatial patterns of relative abundance of seabirds and marine mammals in the eastern Chukchi and western Beaufort seas during summer (15 June-31 August) and fall (1 September-20 November) from 2007 to 2012. We summarized 49,206 km of shipboard surveys for seabirds and 183,157 km of aerial surveys for marine mammals into a grid of 40-km × 40-km cells. We used Getis-Ord Gi∗ hotspot analysis to test for cells with higher relative abundance than expected when compared to all cells within the study area. We identified cells representing single species and taxonomic group hotspots, cells representing hotspots for multiple species, and cells representing hotspots for both seabirds and marine mammals. The locations of hotspots varied among species but often were located near underwater canyons or over continental shelf features and slopes. Hotspots for seabirds, walrus, and gray whales occurred primarily in the Chukchi Sea. Hotspots for bowhead whales and other pinnipeds (i.e., seals) occurred near Barrow Canyon and along the Beaufort Sea shelf and slope. Hotspots for belugas occurred in both the Chukchi and Beaufort seas. There were three hotspots shared by both seabirds and marine mammals in summer: off Wainwright in the eastern Chukchi Sea, south of Hanna Shoal, and at the mouth of Barrow Canyon. In fall, the only identified shared hotspot occurred at the mouth of Barrow Canyon. Shared hotspots are characterized by strong fronts caused by upwelling and currents, and these areas can have high densities of euphausiids in summer and fall. Due to the high relative abundance of animals and diversity of taxa

  6. Avoid Logs to Avoid Ticks

    Institute of Scientific and Technical Information of China (English)

    莫文佳

    2004-01-01

    扁虱是莱姆关节炎的罪魁祸首。研究人员为了弄明白何处扁虱最猖獗, 不惜以身作饵,他们发现:The ticks were all over the log surface。因此告诫人 们:Avoid sitting on logs。

  7. Estimating the impacts of fishing on dependent predators: a case study in the California Current.

    Science.gov (United States)

    Field, J C; MacCall, A D; Bradley, R W; Sydeman, W J

    2010-12-01

    Juvenile rockfish (Sebastes spp.) are important prey to seabirds in the California Current System, particularly during the breeding season. Both seabird breeding success and the abundance of pelagic juvenile rockfish show high interannual variability. This covariation is largely a response to variable ocean conditions; however, fishing on adult rockfish may have had consequences for seabird productivity (e.g., the number of chicks fledged per breeding pair) by reducing the availability of juvenile rockfish to provisioning seabird parents. We tested the hypothesis that fishing has decreased juvenile rockfish availability and thereby limited seabird productivity over the past 30 years. We quantified relationships between observed juvenile rockfish relative abundance and seabird productivity, used fisheries stock assessment approaches to estimate the relative abundance of juvenile rockfish in the absence of fishing, and compared the differences in seabird productivity that would have resulted without rockfish fisheries. We examined the abundance of juvenile rockfish and the corresponding productivity of three seabird species breeding on Southeast Farallon Island (near San Francisco, California, USA) from the early 1980s to the present. Results show that while the relative abundance of juvenile rockfish has declined to approximately 50% of the estimated unfished biomass, seabirds achieved 75-95% of the estimated un-impacted levels of productivity, depending upon the species of bird and various model assumptions. These results primarily reflect seabirds with "conservative" life histories (one egg laid per year) and may be different for species with more flexible life history strategies (greater reproductive effort). Our results are consistent with the premise that the impacts of local rockfish fisheries on seabird productivity are less than impacts that have occurred to the prey resources themselves due to ocean climate and the ability of seabirds to buffer against

  8. Spatial variogram estimation from temporally aggregated seabird count data

    NARCIS (Netherlands)

    Perez-Lapena, Blanca; Wijnberg, Kathelijne Mariken; Stein, A.; Hulscher, Suzanne J.M.H.

    2013-01-01

    Seabird abundance is an important indicator for assessing impact of human activities on the marine environment. However, data collection at sea is time consuming and surveys are carried out over several consecutive days for efficiency reasons. This study investigates the validity of aggregating

  9. Mitigating seabird bycatch during hauling by pelagic longline vessels.

    Directory of Open Access Journals (Sweden)

    Eric Gilman

    Full Text Available Bycatch in longline fisheries threatens the viability of some seabird populations. The Hawaii longline swordfish fishery reduced seabird captures by an order of magnitude primarily through mitigating bycatch during setting. Now, 75% of captures occur during hauling. We fit observer data to a generalized additive regression model with mixed effects to determine the significance of the effect of various factors on the standardized seabird haul catch rate. Density of albatrosses attending vessels during hauling, leader length and year had largest model effects. The standardized haul catch rate significantly increased with increased albatross density during hauling. The standardized catch rate was significantly higher the longer the leader: shorter leaders place weighted swivels closer to hooks, reducing the likelihood of baited hooks becoming available to surface-scavenging albatrosses. There was a significant linear increasing temporal trend in the standardized catch rate, possibly partly due to an observed increasing temporal trend in the local abundance of albatrosses attending vessels during hauling. Swivel weight, Beaufort scale and season were also significant but smaller model effects. Most (81% haul captures were on branchlines actively being retrieved. Future haul mitigation research should therefore focus on reducing bird access to hooks as crew coil branchlines, including methods identified here of shorter leaders and heavier swivels, and other potentially effective methods, including faster branchline coiling and shielding the area where hooks becomes accessible. The proportion of Laysan albatross (Phoebastria immutabilis captures that occurred during hauling was significantly, 1.6 times, higher than for black-footed albatrosses (P. nigripes, perhaps due to differences in the time of day of foraging and in daytime scavenging competitiveness; mitigating haul bycatch would therefore be a larger benefit to Laysans. Locally, findings

  10. Mitigating seabird bycatch during hauling by pelagic longline vessels.

    Science.gov (United States)

    Gilman, Eric; Chaloupka, Milani; Wiedoff, Brett; Willson, Jeremy

    2014-01-01

    Bycatch in longline fisheries threatens the viability of some seabird populations. The Hawaii longline swordfish fishery reduced seabird captures by an order of magnitude primarily through mitigating bycatch during setting. Now, 75% of captures occur during hauling. We fit observer data to a generalized additive regression model with mixed effects to determine the significance of the effect of various factors on the standardized seabird haul catch rate. Density of albatrosses attending vessels during hauling, leader length and year had largest model effects. The standardized haul catch rate significantly increased with increased albatross density during hauling. The standardized catch rate was significantly higher the longer the leader: shorter leaders place weighted swivels closer to hooks, reducing the likelihood of baited hooks becoming available to surface-scavenging albatrosses. There was a significant linear increasing temporal trend in the standardized catch rate, possibly partly due to an observed increasing temporal trend in the local abundance of albatrosses attending vessels during hauling. Swivel weight, Beaufort scale and season were also significant but smaller model effects. Most (81%) haul captures were on branchlines actively being retrieved. Future haul mitigation research should therefore focus on reducing bird access to hooks as crew coil branchlines, including methods identified here of shorter leaders and heavier swivels, and other potentially effective methods, including faster branchline coiling and shielding the area where hooks becomes accessible. The proportion of Laysan albatross (Phoebastria immutabilis) captures that occurred during hauling was significantly, 1.6 times, higher than for black-footed albatrosses (P. nigripes), perhaps due to differences in the time of day of foraging and in daytime scavenging competitiveness; mitigating haul bycatch would therefore be a larger benefit to Laysans. Locally, findings identify opportunities

  11. Seabird eggs as bioindicators of chemical contamination in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Cifuentes, Jacqueline Munoz; Becker, Peter H.; Sommer, Ute; Pacheco, Patricia; Schlatter, Roberto

    2003-11-01

    Seabird eggs are proposed as biomonitors of chemical contamination in Chile. - Seabird eggs were used as bioindicators of chemical contamination in Chile. Brown-hooded Gull (Larus maculipennis), Kelp Gull (Larus dominicanus), Trudeau's Tern (Sterna trudeaui), Neotropic Cormorant (Phalacrocorax brasilianus), and Pink-footed Shearwater (Puffinus creatopus) eggs were sampled at different breeding sites during the 1990s. Mercury and organochlorines (PCBs, DDT, HCB, HCH, and PCP) were quantified to reveal the interspecific differences, spatial and temporal trends in contamination levels. Trudeau's Tern displayed the highest levels of mercury (486 ng g{sup -1} wet weight). The highest {sigma}DDT concentrations were measured in Brown-hooded Gulls (726 ng g{sup -1}). PCB levels were similar among the species (102-236 ng g{sup -1}), but the composition of the PCB mixture was different in Pink-footed Shearwaters. With the exception of the Brown-hooded Gull, all species studied presented similar and low levels of organochlorines ({sigma}OHa). Residues of PCB and related compounds were not detected in any of the seabird eggs analyzed in Chile. Geographical variation was low, although levels of industrial chemicals were slightly higher in eggs from Concepcion Bay, and agricultural chemicals in eggs from Valdivia. Also interannual variation was low, but some evidence was found of decreasing levels in gull eggs throughout the time of the study. The causes of the low levels and small variability in space and time of environmental chemicals in Chilean seabirds are discussed. We propose the use of seabirds in future monitoring of the development of chemical contamination in Chile.

  12. Influence of Seasonal Food Availability on the Dynamics of Seabird Feeding Flocks at a Coastal Upwelling Area.

    Directory of Open Access Journals (Sweden)

    Cristóbal Anguita

    Full Text Available The formation of multi-species feeding flocks (MSFFs through visual recruitment is considered an important strategy for obtaining food in seabirds and its functionality has been ascribed to enhanced foraging efficiency. Its use has been demonstrated in much of the world's oceans and includes numerous species. However, there is scant information on the temporal stability of the composition and abundance of MSFFs as well as the effect of seasonal food availability on their dynamics. Between July 2006 and September 2014, we conducted monthly at-sea seabird counts at Valparaiso Bay (32°56' to 33°01'S, 71°36' to 71°46'W within the area of influence of the Humboldt Current in central Chile. This area is characterized by a marked seasonality in primary and secondary production associated with upwelling, mainly during austral spring-summer. Based on studies that provide evidence that flocking is most frequent when food is both scarce and patchy, we hypothesized that seabird MSFF attributes (i.e. frequency of occurrence, abundance and composition will be modified according to the seasonal availability of food. Using generalized linear models (GLMs, our results show that the contrasting seasonality in food availability of the study area (using chlorophyll-a concentration as a proxy had no significant influence on MSFF attributes, sparsely explaining their variations (P>0.05. Rather than seasonal food availability, the observed pattern for MSFF attributes at Valparaiso Bay suggests a substantial influence of reproductive and migratory (boreal and austral migrants habits of birds that modulates MSFF dynamics consistently throughout the whole year in this highly variable and patchy environment. We highlight the importance of visual recruitment as a mechanism by which migratory and resident birds interact. This would allow them to reduce resource unpredictability, which in turn has a major impact on structuring seabird's MSFF dynamics.

  13. Monitoring Seabirds and Marine Mammals by Georeferenced Aerial Photography

    Science.gov (United States)

    Kemper, G.; Weidauer, A.; Coppack, T.

    2016-06-01

    The assessment of anthropogenic impacts on the marine environment is challenged by the accessibility, accuracy and validity of biogeographical information. Offshore wind farm projects require large-scale ecological surveys before, during and after construction, in order to assess potential effects on the distribution and abundance of protected species. The robustness of site-specific population estimates depends largely on the extent and design of spatial coverage and the accuracy of the applied census technique. Standard environmental assessment studies in Germany have so far included aerial visual surveys to evaluate potential impacts of offshore wind farms on seabirds and marine mammals. However, low flight altitudes, necessary for the visual classification of species, disturb sensitive bird species and also hold significant safety risks for the observers. Thus, aerial surveys based on high-resolution digital imagery, which can be carried out at higher (safer) flight altitudes (beyond the rotor-swept zone of the wind turbines) have become a mandatory requirement, technically solving the problem of distant-related observation bias. A purpose-assembled imagery system including medium-format cameras in conjunction with a dedicated geo-positioning platform delivers series of orthogonal digital images that meet the current technical requirements of authorities for surveying marine wildlife at a comparatively low cost. At a flight altitude of 425 m, a focal length of 110 mm, implemented forward motion compensation (FMC) and exposure times ranging between 1/1600 and 1/1000 s, the twin-camera system generates high quality 16 bit RGB images with a ground sampling distance (GSD) of 2 cm and an image footprint of 155 x 410 m. The image files are readily transferrable to a GIS environment for further editing, taking overlapping image areas and areas affected by glare into account. The imagery can be routinely screened by the human eye guided by purpose-programmed software

  14. New records, distribution and status of six seabird species in Brazil

    Directory of Open Access Journals (Sweden)

    Rafael Antunes Dias

    2010-12-01

    Full Text Available Distribution records of poorly-known species are currently the most explored theme in the Brazilian seabird literature. If properly evaluated, this kind of information can improve our knowledge on distribution, migration and status of occurrence of these species. In this note we present new records for six species of poorly-known seabirds in the Brazilian coast, reviewing distribution records and defining their status of occurrence in the country. We consider Chionis albus (Gmelin, 1789 a pseudo-vagrant in Brazil and define its status as a scarce seasonal visitor from southern South America. We present the first records of Leucophaeus atricilla (Linnaeus, 1758 for Trindade Island, and of Leucophaeus pipixcan (Wagler, 1831 for the state of Rio Grande do Sul, and determined that the former is a vagrant in eastern Brazil and the latter a vagrant across the country. Anous stolidus (Linnaeus, 1758 is a vagrant in southernmost Brazil. We were unable to determine if records of Chlidonias niger (Linnaeus, 1758 for Brazil and southern South America refer to vagrancy or pseudo-vagrancy. Additionally, we verified the occurrence of breeding individuals of Anous minutus Boie, 1844 on Martin Vaz Island and confirmed that there is no evidence of breeding on neighboring Trindade Island.

  15. Trophic ecology drives contaminant concentrations within a tropical seabird community.

    Science.gov (United States)

    Sebastiano, Manrico; Bustamante, Paco; Eulaers, Igor; Malarvannan, Govindan; Mendez-Fernandez, Paula; Churlaud, Carine; Blévin, Pierre; Hauselmann, Antoine; Covaci, Adrian; Eens, Marcel; Costantini, David; Chastel, Olivier

    2017-08-01

    To support environmental management programs, there is an urgent need to know about the presence and understand the dynamics of major contaminants in seabird communities of key marine ecosystems. In this study, we investigated the concentrations and trophodynamics of trace elements in six seabird species and persistent organic pollutants (POPs) in three seabird species breeding on Grand Connétable Island (French Guiana), an area where the increase in human population and mining activities has raised concerns in recent years. Red blood cell Hg concentrations in adults were the highest in Magnificent frigatebirds Fregata magnificens (median: 5.6 μg g(-1) dw; range: 3.8-7.8 μg g(-1) dw) and lowest in Sooty terns Onychoprion fuscatus (median: 0.9 μg g(-1) dw; range: 0.6-1.1 μg g(-1) dw). Among POPs, dichlorodiphenyldichloroethylene (p,p'-DDE) was the most abundant compound in plasma of Cayenne terns Thalasseus sandvicensis (median: 1100 pg g(-1) ww; range: 160 ± 5100 pg g(-1) ww), while polychlorinated biphenyls (PCBs) were the most abundant compound class in plasma of Magnificent frigatebirds (median: 640 pg g(-1) ww; range 330 ± 2700 pg g(-1) ww). While low intensity of POP exposure does not appear to pose a health threat to this seabird community, Hg concentration in several adults Laughing gulls Leucophaeus atricilla and Royal terns Thalasseus maximus, and in all Magnificent frigatebirds was similar or higher than that of high contaminated seabird populations. Furthermore, nestling red blood cells also contained Hg concentrations of concern, and further studies should investigate its potential health impact in this seabird community. Differences in adult trophic ecology of the six species explained interspecific variation in exposure to trace element and POPs, while nestling trophic ecology provides indications about the diverse feeding strategies adopted by the six species, with the consequent variation in exposure to contaminants

  16. Polychlorinated biphenyls and organochlorine pesticides in plastics ingested by seabirds.

    Science.gov (United States)

    Colabuono, Fernanda Imperatrice; Taniguchi, Satie; Montone, Rosalinda Carmela

    2010-04-01

    The occurrence of plastic objects in the digestive tract was assessed in eight species of Procellariiformes collected in southern Brazil and the occurrence of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the ingested plastics pellets and plastic fragments was evaluated. PCBs were detected in plastic pellets (491 ng g(-1)) and plastic fragments (243-418 ng g(-1)). Among the OCPs, p,p'-DDE had the highest concentrations, ranging from 68.0 to 99.0 ng g(-1). The occurrence of organic pollutants in post-consumer plastics supports the fact that plastics are an important source carrying persistent organic pollutants in the marine environment. Although transfer through the food chain may be the main source of exposure to POPs to seabirds, plastics could be an additional source for the organisms which ingest them, like Procellariiformes which are the seabirds most affected by plastic pollution.

  17. Offshore Seabird Distributions during Summer and Autumn at West Greenland

    DEFF Research Database (Denmark)

    Boertmann, D.; Mosbech, A.

    This report presents the phenological and distributional results of seabird surveys carried out by ship in West Greenland waters. In 1977 observations were carried out from stationary platforms (oil exploration supply ships) and in the period 1992 to 2000 observations were carried out from sailing...... ships. The results from 1977 are presented as observations per 5-day periods and give an impression of the species temporal occurrence. The 1992-2000 results are presented as distribution maps. These show densities for more numerous and widespread species, and actual observations for the less numerous....... During the autumn the numbers of seabirds increase as migrants from local and international populations of mainly thick-billed murre and little auk arrive to spend the winter in West Greenland waters. Huge concentrations of thick-billed murres, common eiders and king-eiders may occur then...

  18. Prevalence of blood parasites in seabirds - a review

    Directory of Open Access Journals (Sweden)

    Quillfeldt Petra

    2011-10-01

    Full Text Available Abstract Introduction While blood parasites are common in many birds in the wild, some groups seem to be much less affected. Seabirds, in particular, have often been reported free from blood parasites, even in the presence of potential vectors. Results From a literature review of hemosporidian prevalence in seabirds, we collated a dataset of 60 species, in which at least 15 individuals had been examined. These data were included in phylogenetically controlled statistical analyses of hemosporidian prevalence in relation to ecological and life-history parameters. Haemoproteus parasites were common in frigatebirds and gulls, while Hepatozoon occurred in albatrosses and storm petrels, and Plasmodium mainly in penguins. The prevalence of Haemoproteus showed a geographical signal, being lower in species with distribution towards polar environments. Interspecific differences in Plasmodium prevalence were explained by variables that relate to the exposure to parasites, suggesting that prevalence is higher in burrow nesters with long fledgling periods. Measures of Plasmodium, but not Haemoproteus prevalences were influenced by the method, with PCR-based data resulting in higher prevalence estimates. Conclusions Our analyses suggest that, as in other avian taxa, phylogenetic, ecological and life-history parameters determine the prevalence of hemosporidian parasites in seabirds. We discuss how these relationships should be further explored in future studies.

  19. Identification of an assembly site for migratory and tropical seabirds in the South Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    B. John Hughes

    2015-07-01

    Full Text Available Seabirds are good indicators of wider biodiversity and where they assemble in large numbers signifies sites important to many marine faunal species. Few such large assemblage sites have been identified and none in pelagic waters has been identified in the tropical Atlantic Ocean despite their importance for resident seabirds and those ‘on passage’ during migration. Here, we identify the likely location of just such an assembly site and provide preliminary information about the distribution of pelagic seabirds around Ascension Island in the tropical South Atlantic Ocean using a combination of trans-equatorial seabird migrant tracking data, records of at-sea surveys and land counts of seabirds returning from foraging trips. We found that waters north–north-west of Ascension Island are used more often by seabirds than those south and east of the island. Three-fifths of the species recorded in the assembly site breed at mid- or high-latitudes and some of these migratory seabirds stopover possibly to wait for favourable winds that facilitate onward flight. Our findings are important because to the best of our knowledge no seabird assembly sites have previously been identified in tropical Atlantic Ocean pelagic waters. We provide evidence to support the aspirations of the Marine Reserves Coalition that waters in the vicinity of Ascension Island should be recognised as a sanctuary for marine wildlife and we highlight an area that is worthy of further targeted investigation.

  20. Interspecies and spatial trends in polycyclic aromatic hydrocarbons (PAHs) in Atlantic and Mediterranean pelagic seabirds

    Energy Technology Data Exchange (ETDEWEB)

    Roscales, Jose L., E-mail: jlroscales@iqog.csic.es [Research Institute of Biodiversity (IRBio) and department of Animal Biology (Vertebrates), Barcelona University, Av Diagonal 645, 08028 Barcelona (Spain); Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Gonzalez-Solis, Jacob [Research Institute of Biodiversity (IRBio) and department of Animal Biology (Vertebrates), Barcelona University, Av Diagonal 645, 08028 Barcelona (Spain); Calabuig, Pascual [Wildlife Fauna Tafira Recuperation Center, Cabildo de Gran Canaria, Canary Islands (Spain); Jimenez, Begona [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)

    2011-10-15

    PAHs were analyzed in the liver of 5 species of pelagic seabirds (Procellariiformes) from the northeast Atlantic and the Mediterranean. The main objective was to assess the trophic and geographic trends of PAHs in seabirds to evaluate their suitability as bioindicators of chronic marine pollution by these compounds. Although higher levels of PAHs have been described in the Mediterranean compared to other oceanic regions, we did not find significant spatial patterns and observed only minor effects of the geographic origin on seabird PAHs. However, we found significant higher PAH levels in petrel compared to shearwater species, which could be related to differences in their exploitation of mesopelagic and epipelagic resources, respectively, and the vertical dynamic of PAHs in the water column. Overall, although this study enhances the need of multi-species approaches to show a more comprehensive evaluation of marine pollution, seabirds emerged as poor indicators of pelagic chronic PAH levels. - Highlights: > PAHs in pelagic seabirds show specific inter-species patterns related to trophic ecology. > Geographic origin shows a minor effect over PAH levels in pelagic seabirds. > Pelagic seabirds seem to be poor indicators of chronic PAH levels. - PAH levels in Atlantic and Mediterranean pelagic seabirds show specific inter-species patterns related to trophic ecology but a minor influence of their geographic origin.

  1. Rickettsia spp. in seabird ticks from western Indian Ocean islands, 2011-2012.

    Science.gov (United States)

    Dietrich, Muriel; Lebarbenchon, Camille; Jaeger, Audrey; Le Rouzic, Céline; Bastien, Matthieu; Lagadec, Erwan; McCoy, Karen D; Pascalis, Hervé; Le Corre, Matthieu; Dellagi, Koussay; Tortosa, Pablo

    2014-05-01

    We found a diversity of Rickettsia spp. in seabird ticks from 6 tropical islands. The bacteria showed strong host specificity and sequence similarity with strains in other regions. Seabird ticks may be key reservoirs for pathogenic Rickettsia spp., and bird hosts may have a role in dispersing ticks and tick-associated infectious agents over large distances.

  2. Airborne Collision Avoidance System X

    Science.gov (United States)

    2015-06-01

    avoidance system on behalf of the Federal Aviation Adminis- tration (FAA). The current Traffic Alert and Collision Avoidance System II (TCAS II...transformations to the National Airspace System are being imple- mented through the FAA’s Next-Genera- tion Air Transportation System (NextGen). With the goal...weighted states to provide a single, optimal action. If a collision avoidance This work is sponsored by the Federal Aviation Administration under Air

  3. Teachers Avoiding Learners' Avoidance: Is It Possible?

    Science.gov (United States)

    Tadayyon, Maedeh; Zarrinabadi, Nourollah; Ketabi, Saeed

    2016-01-01

    Dealing with learners who prefer to take the back seat and avoid classroom participation can be every teacher's nightmare. This lack of participation may cause teacher frustration, and possibly the only way to reduce this lack of participation is to access the concept of avoidance strategy. Avoidance strategy is the abandonment of a classroom task…

  4. Evidence for Borrelia bavariensis infections of Ixodes uriae within seabird colonies of the North Atlantic Ocean.

    Science.gov (United States)

    Munro, Hannah J; Ogden, Nicholas H; Lindsay, L Robbin; Robertson, Gregory J; Whitney, Hugh; Lang, Andrew S

    2017-08-11

    The first report of members of the spirochete genus Borrelia in the seabird tick, Ixodes uriae, and seabird colonies occurred during the early 1990s. Since then, Borrelia spp. have been detected in these ticks and seabird colonies around the world. To-date, the primary species detected has been B. garinii, with rare occurrences of B. burgdorferi sensu stricto and B. lusitaniae. During our research on Borrelia and I. uriae in seabird colonies of Newfoundland and Labrador, Canada, we have identified B. bavariensis in I. uriae To our knowledge, B. bavariensis has previously only been found in the Eurasian tick species, I. persulcatus and I. ricinus, and it was believed to be a rodent-specific Borrelia ecotype. We found B. bavariensis within I. uriae from three seabird colonies, over three calendar years. We also reanalyzed B. garinii sequences collected from I. uriae from Eurasian seabird colonies, and determined that sequences from two Russian seabird colonies likely also represent B. bavariensis The Canadian B. bavariensis sequences from I. uriae analysed in this study cluster with previously described sequences from Asia. Overall, this is an important discovery that illustrates and expands the range of hosts and vectors for B. bavariensis and it raises questions regarding the possible mechanisms of pathogen dispersal from Asia to North America.Importance To our knowledge this is the first documentation of B. bavariensis outside Eurasia. Additionally, the bacterium was found in a marine ecosystem involving the seabird tick, I. uriae, and its associated seabird hosts. This indicates the epizootiology of B. bavariensis transmission is much different from what was previously described, with this species previously believed to be a rodent-specific ecotype, and indicates that this pathogen is established, or establishing, much more widely. © Crown copyright 2017.

  5. Shrimp trawlers as a local attractor of seabirds in nearshore waters of South Carolina, USA

    Science.gov (United States)

    Jodice, Patrick G.; Wickliffe, Lisa C.; Sachs, Elena B.

    2011-01-01

    Shrimp trawling is common throughout the southeastern and Gulf of Mexico coasts of the USA and is the primary contributor to fisheries discards in these regions. Tens of thousands of nearshore seabirds nest near shrimp trawling grounds in the USA, but to date, there has been no assessment of the relationship between seabirds and shrimp trawlers. We examined the taxonomic composition of bycatch, rate at which seabirds scavenged bycatch, and energy density of discarded bycatch in a nearshore commercial shrimp fishery. Bycatch was primarily comprised of demersal fish that are not typically accessible to the plunge-diving and surface-feeding seabirds that occur in the area. Hence, seabird diets in the region appear to be broadened taxonomically by the availability of discards. Results from discard experiments indicated that 70% of the nearly 5,500 items discarded by hand were scavenged by seabirds and that the fate of a discarded item was most strongly predicted by its taxonomic order. Laughing gulls scavenged the greatest proportion of discards, although brown pelicans were the only species to scavenge more discards than predicted based upon their abundance. Because this is the first such study in the region, it is difficult to ascertain the extent or intensity of the impact that discards have on nearshore seabirds. Nonetheless, our results suggest that it will be difficult for managers to clearly understand fluctuations in local seabird population dynamics without first understanding the extent to which these species rely upon discards. This may be especially problematic in situations where seabird populations are recovering following natural or anthropogenic stressors.

  6. Population dynamics of Hawaiian seabird colonies vulnerable to sea-level rise

    Science.gov (United States)

    Hatfield, Jeff S.; Reynolds, Michelle H.; Seavy, Nathaniel E.; Krause, Crystal M.

    2012-01-01

    Globally, seabirds are vulnerable to anthropogenic threats both at sea and on land. Seabirds typically nest colonially and show strong fidelity to natal colonies, and such colonies on low-lying islands may be threatened by sea-level rise. We used French Frigate Shoals, the largest atoll in the Hawaiian Archipelago, as a case study to explore the population dynamics of seabird colonies and the potential effects sea-level rise may have on these rookeries. We compiled historic observations, a 30-year time series of seabird population abundance, lidar-derived elevations, and aerial imagery of all the islands of French Frigate Shoals. To estimate the population dynamics of 8 species of breeding seabirds on Tern Island from 1980 to 2009, we used a Gompertz model with a Bayesian approach to infer population growth rates, density dependence, process variation, and observation error. All species increased in abundance, in a pattern that provided evidence of density dependence. Great Frigatebirds (Fregata minor), Masked Boobies (Sula dactylatra), Red-tailed Tropicbirds (Phaethon rubricauda), Spectacled Terns (Onychoprion lunatus), and White Terns (Gygis alba) are likely at carrying capacity. Density dependence may exacerbate the effects of sea-level rise on seabirds because populations near carrying capacity on an island will be more negatively affected than populations with room for growth. We projected 12% of French Frigate Shoals will be inundated if sea level rises 1 m and 28% if sea level rises 2 m. Spectacled Terns and shrub-nesting species are especially vulnerable to sea-level rise, but seawalls and habitat restoration may mitigate the effects of sea-level rise. Losses of seabird nesting habitat may be substantial in the Hawaiian Islands by 2100 if sea levels rise 2 m. Restoration of higher-elevation seabird colonies represent a more enduring conservation solution for Pacific seabirds.

  7. A mechanistic link between chick diet and decline in seabirds?

    Science.gov (United States)

    Kitaysky, A.S.; Kitaiskaia, E.V.; Piatt, J.F.; Wingfield, J.C.

    2006-01-01

    A climatic regime shift during the mid-1970s in the North Pacific resulted in decreased availability of lipidrich fish to seabirds and was followed by a dramatic decline in number of kittiwakes breeding on the Pribilof Islands. Although production of chicks in the mid-1970s was adequate to sustain kittiwake populations in the early 1980s, the disappearance of birds from breeding colonies apparently exceeded recruitment. No mechanism has been proposed to explain why recruitment would differ among fledglings fed lipid-rich or lipid-poor fish during development. Here we show that diets low in lipids induce nutritional stress and impair cognitive abilities in young red-legged kittiwakes, Rissa brevirostris. Specifically, growth retardation, increased secretion of stress hormones and inferior ability to associate food distribution with visual cues were observed in individuals fed lipid-poor diets. We conclude that lipid-poor diets during development affect the quality of young seabirds, which is likely to result in their increased mortality and low recruitment. ?? 2005 The Royal Society.

  8. Metal concentrations in pelagic seabirds from the North Pacific Ocean.

    Science.gov (United States)

    Honda, K; Marcovecchio, J E; Kan, S; Tatsukawa, R; Ogi, H

    1990-01-01

    Concentrations of four essential elements (Fe, Mn, Zn, and Cu) and two toxic metals (Cd and Hg) were measured in selected tissues of 19 pelagic seabird species collected in the North Pacific and neighboring waters. Essential metal concentrations were generally highest in the liver and less variable than toxic metals among species and also within each species. Fe concentrations in the muscle were higher in Alcidae than in the other families, whereas the opposite trend was found for Fe and Mn in the liver. Zn concentrations varied among species, depending on the Cd concentrations. On the other hand, toxic metal concentrations were highest in the liver or kidney and varied widely among species, greatly depending on differences in the diet among species. Extraordinarily high Hg concentrations were found in Black-footed Albatrosses,Diomedea nigripes, exceeding 300 μg/g wet weight in some, and seemed to be due to constraints on the elimination of Hg. Also, some geographical differences in Cd and Hg concentrations of the seabirds were observed. The concentrations of Cd and Hg reported here, however, seem to be natural rather than due to environmental pollution.

  9. Varying foraging patterns in response to competition? A multicolony approach in a generalist seabird.

    Science.gov (United States)

    Corman, Anna-Marie; Mendel, Bettina; Voigt, Christian C; Garthe, Stefan

    2016-02-01

    Reducing resource competition is a crucial requirement for colonial seabirds to ensure adequate self- and chick-provisioning during breeding season. Spatial segregation is a common avoidance strategy among and within species from neighboring breeding colonies. We determined whether the foraging behaviors of incubating lesser black-backed gulls (Larus fuscus) differed between six colonies varying in size and distance to mainland, and whether any differences could be related to the foraging habitats visited. Seventy-nine incubating individuals from six study colonies along the German North Sea coast were equipped with GPS data loggers in multiple years. Dietary information was gained by sampling food pellets, and blood samples were taken for stable isotope analyses. Foraging patterns clearly differed among and within colonies. Foraging range increased with increasing colony size and decreased with increasing colony distance from the mainland, although the latter might be due to the inclusion of the only offshore colony. Gulls from larger colonies with consequently greater density-dependent competition were more likely to forage at land instead of at sea. The diets of the gulls from the colonies furthest from each other differed, while the diets from the other colonies overlapped with each other. The spatial segregation and dietary similarities suggest that lesser black-backed gulls foraged at different sites and utilized two main habitat types, although these were similar across foraging areas for all colonies except the single offshore island. The avoidance of intraspecific competition results in colony-specific foraging patterns, potentially causing more intensive utilization of terrestrial foraging sites, which may offer more predictable and easily available foraging compared with the marine environment.

  10. Predicting Future European Breeding Distributions of British Seabird Species under Climate Change and Unlimited/No Dispersal Scenarios

    Directory of Open Access Journals (Sweden)

    Deborah J.F. Russell

    2015-11-01

    Full Text Available Understanding which traits make species vulnerable to climatic change and predicting future distributions permits conservation efforts to be focused on the most vulnerable species and the most appropriate sites. Here, we combine climate envelope models with predicted bioclimatic data from two emission scenarios leading up to 2100, to predict European breeding distributions of 23 seabird species that currently breed in the British Isles. Assuming unlimited dispersal, some species would be “winners” (increase the size of their range, but over 65% would lose range, some by up to 80%. These “losers” have a high vulnerability to low prey availability, and a northerly distribution meaning they would lack space to move into. Under the worst-case scenario of no dispersal, species are predicted to lose between 25% and 100% of their range, so dispersal ability is a key constraint on future range sizes. More globally, the results indicate, based on foraging ecology, which seabird species are likely to be most affected by climatic change. Neither of the emissions scenarios used in this study is extreme, yet they generate very different predictions for some species, illustrating that even small decreases in emissions could yield large benefits for conservation.

  11. Pacific Remote Islands MNM: Initial Survey Instructions for Seabird Colony Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of the seabird survey is to assess, to the extent possible within the period of time available ashore, the species composition, number of adults, number...

  12. Reproductive ecology of seabirds at Middletown Island, Alaska, 14-26 June 1981: Trip report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is a summary of reproductive ecology of seabirds at Middleton Island, Alaska from June 14-26 1981. Species covered include Black-legged kittiwakes and...

  13. The historical status of nesting seabirds of the northern and western Gulf of Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The coming of the tanker terminal at Valdez and the pending development of oil and gas resources on the outer continental shelf threaten massive change for seabirds...

  14. Widespread mortality of adult seabirds in Alaska, August-September 1983

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A widespread die-off of adult seabirds, affecting primarily the black-legged kittiwake (Rissa tridactyla), and short-tailed shearwater (Puffinus tenuirostris),...

  15. Breeding seabirds at Gull Island and Sixty-foot Rock during 1987-88

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the results of a series of breeding seabird surveys taken on Gull Island and Sixty-foot Rock during 1987 and 1988. A description of the study...

  16. Populations and productivity of seabirds on the pacific coast of Becharof National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Colonial seabirds (murres, cormorants, gulls, puffins, and kittiwakes) were monitored along the Pacific Coast of the Becharof National Wildlife Refuge (NWR) to...

  17. Breeding status, population trends and diets of seabirds in Alaska, 2008

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is the thirteenth in a series of annual reports summarizing the results of seabird monitoring efforts at breeding colonies on the Alaska Maritime...

  18. Challenges to Oil Spill Assessment for Seabirds in the Deep Ocean.

    Science.gov (United States)

    Haney, J Christopher; Jodice, Patrick G R; Montevecchi, William A; Evers, David C

    2017-07-01

    We synthesize impediments for evaluating effects to seabirds from open ocean hydrocarbon releases. Effects on seabirds from ship discharges, spills, and well blowouts often are poorly detected and monitored far from land. Regulatory regimes for ocean spills can result in monitoring efforts that are not entirely transparent. We illustrate how interdisciplinary technologies address deficits that hamper individual or population level assessments for seabirds, and we demonstrate where emerging technologies might be engaged to bridge gaps in oil spill monitoring. Although acute mortality from direct oil exposure poses the greatest risk to seabirds, other hazards from light-attraction, flaring, collisions, chronic pollution, and hydrocarbon inhalation around oil infrastructure also may induce bird mortality in the deep ocean.

  19. Distribution and abundance of breeding seabirds in Chiniak and southern Marmot Bays, Kodiak Island, Alaska, 1975

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A census survey of breeding seabirds was conducted by boat and airplane in Chiniak and southern Marmot Bays, Kodiak Island, Alaska, from 15 June to 14 August 1975. A...

  20. Determine disturbance impacts of fireworks at the Coquille Point seabird colony complex near Bandon, Oregon

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The USFWS conducted a monitoring study at Pirate Cove Rock during 2011 to determine if the Independence Day fireworks display had any adverse effects on seabirds,...

  1. Results of the 1986 seabird monitoring program at Cape Lisburne, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers the results of the 1986 seabird monitoring program at Cape Lisburne, Alaska. Objectives of this reports includes determining reproductive success,...

  2. An effort to trap mink in Maine to protect nesting Seabirds 1998

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report details and effort to trap minks on the islands of Otter, Roberts, Carvers and Hay during the spring of 1998. This is to benefit and protect the seabirds...

  3. An effort to trap mink in Maine to protect nesting Seabirds 2000

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Mink were trapped off the seabird nesting islands south east of Vinalhaven, Maine (outer Penobscot Bay) during the late 1990's, and the local Black Guillemot...

  4. Threat of plastic pollution to seabirds is global, pervasive, and increasing

    OpenAIRE

    Wilcox, Chris; van Sebille, Erik; Hardesty, Britta Denise

    2015-01-01

    Plastic pollution in the ocean is a rapidly emerging global environmental concern, with high concentrations (up to 580,000 pieces per km2) and a global distribution, driven by exponentially increasing production. Seabirds are particularly vulnerable to this type of pollution and are widely observed to ingest floating plastic. We used a mixture of literature surveys, oceanographic modeling, and ecological models to predict the risk of plastic ingestion to 186 seabird species globally. Impacts ...

  5. Sensitivity of tropical seabirds to El Niño precursors.

    Science.gov (United States)

    Devney, Carol A; Short, Michael; Congdon, Bradley C

    2009-05-01

    Intense El Niño events severely impact seabird populations, often months in advance of peak temperature anomalies. The trophic mechanisms responsible for these impacts are unknown but are assumed to operate at seasonal scales and to be linked to ocean productivity changes. Precursors to El Niño events include changes in both sea-surface temperature and the depth of the 20 degrees C thermocline. Foraging piscivorous seabirds are known to be sensitive to both thermocline depth and sea-surface temperature change, but the potential influence of these phenomena on breeding dynamics is unknown. Using 18 years of data on three seabirds of the western tropical Pacific, we show that pelagic seabird breeding participation is directly and independently related to changes in both surface chlorophyll concentration and thermocline depth that occur well in advance of El Niño generated sea-surface temperature anomalies. In contrast, breeding in an inshore foraging species is not correlated with any environmental/biological parameters investigated. These findings demonstrate that El Niño related phenomena do not affect seabird prey dynamics solely via productivity shifts at seasonal scales, nor in similar ways across different seabird foraging guilds. Our results also suggest that population declines observed in the western tropical Pacific may be directly related to the frequency and intensity of El Niño anomalies over the study period.

  6. Orbiviruses and bunyaviruses from a seabird colony in Scotland.

    Science.gov (United States)

    Nuttall, P A; Carey, D; Reid, H W; Harrap, K A

    1981-11-01

    Viruses isolated from ticks (Ixodes uriae) and a kittiwake (Rissa tridactyla) from a seabird colony at St. Abb's Head, Scotland, were shown by complement fixation tests (CFT) to be antigenically related to the Uukuniemi and Kemerovo serogroups. Electron microscopic examination of cell cultures infected with the Kemerovo group viruses revealed particles characteristic of orbiviruses, 72 +/- 3 nm in diam., with an inner core 37 +/- 3 nm in diam., in association with intracytoplasmic, densely staining granular areas, and with fibrillar and tubular structures. Cell cultures infected with the Uukuniemi group viruses revealed characteristic bunyavirus particles, 94 +/- 7 nm in diam., with a closely adherent envelope. Both orbi- and bunyaviruses were isolated from two tick pools and the kittiwake. A third tick pool contained an orbivirus which cross-reacted with the other isolates in CFT and fluorescent antibody tests, but was distinguished from them by neutralization tests.

  7. Unexpected hydrogen isotope variation in oceanic pelagic seabirds

    Science.gov (United States)

    Ostrom, Peggy H.; Wiley, Anne E.; Rossman, Sam; Stricker, Craig A.; James, Helen F.

    2014-01-01

    Hydrogen isotopes have significantly enhanced our understanding of the biogeography of migratory animals. The basis for this methodology lies in predictable, continental patterns of precipitation δD values that are often reflected in an organism's tissues. δD variation is not expected for oceanic pelagic organisms whose dietary hydrogen (water and organic hydrogen in prey) is transferred up the food web from an isotopically homogeneous water source. We report a 142% range in the δD values of flight feathers from the Hawaiian petrel (Pterodroma sandwichensis), an oceanic pelagic North Pacific species, and inquire about the source of that variation. We show δD variation between and within four other oceanic pelagic species: Newell's shearwater (Puffinus auricularis newellii), Black-footed albatross (Phoebastria nigripes), Laysan albatross (Phoebastria immutabilis) and Buller's shearwater (Puffinus bulleri). The similarity between muscle δD values of hatch-year Hawaiian petrels and their prey suggests that trophic fractionation does not influence δD values of muscle. We hypothesize that isotopic discrimination is associated with water loss during salt excretion through salt glands. Salt load differs between seabirds that consume isosmotic squid and crustaceans and those that feed on hyposmotic teleost fish. In support of the salt gland hypothesis, we show an inverse relationship between δD and percent teleost fish in diet for three seabird species. Our results demonstrate the utility of δD in the study of oceanic consumers, while also contributing to a better understanding of δD systematics, the basis for one of the most commonly utilized isotope tools in avian ecology.

  8. Unexpected hydrogen isotope variation in oceanic pelagic seabirds.

    Science.gov (United States)

    Ostrom, Peggy H; Wiley, Anne E; Rossman, Sam; Stricker, Craig A; James, Helen F

    2014-08-01

    Hydrogen isotopes have significantly enhanced our understanding of the biogeography of migratory animals. The basis for this methodology lies in predictable, continental patterns of precipitation δD values that are often reflected in an organism's tissues. δD variation is not expected for oceanic pelagic organisms whose dietary hydrogen (water and organic hydrogen in prey) is transferred up the food web from an isotopically homogeneous water source. We report a 142‰ range in the δD values of flight feathers from the Hawaiian petrel (Pterodroma sandwichensis), an oceanic pelagic North Pacific species, and inquire about the source of that variation. We show δD variation between and within four other oceanic pelagic species: Newell's shearwater (Puffinus auricularis newellii), Black-footed albatross (Phoebastria nigripes), Laysan albatross (Phoebastria immutabilis) and Buller's shearwater (Puffinus bulleri). The similarity between muscle δD values of hatch-year Hawaiian petrels and their prey suggests that trophic fractionation does not influence δD values of muscle. We hypothesize that isotopic discrimination is associated with water loss during salt excretion through salt glands. Salt load differs between seabirds that consume isosmotic squid and crustaceans and those that feed on hyposmotic teleost fish. In support of the salt gland hypothesis, we show an inverse relationship between δD and percent teleost fish in diet for three seabird species. Our results demonstrate the utility of δD in the study of oceanic consumers, while also contributing to a better understanding of δD systematics, the basis for one of the most commonly utilized isotope tools in avian ecology.

  9. Low-temperature synthesis to achieve high critical current density and avoid a reaction layer in SmFeAsO1-x F x superconducting tapes

    Science.gov (United States)

    Zhang, Qianjun; Lin, He; Yuan, Pusheng; Zhang, Xianping; Yao, Chao; Wang, Dongliang; Dong, Chiheng; Ma, Yanwei; Awaji, Satoshi; Watanabe, Kazuo

    2015-10-01

    A low-temperature (300-500 °C) heat treatment process under ambient pressure or uniaxial pressure was performed on Sn-added SmFeAsO1-x F x superconducting tapes fabricated by the ex situ powder-in-tube method. A highest transport critical current density (J c) of 3.95 × 104 A cm-2 (at 4.2 K and self-field) was achieved by this process. The low-temperature process allows tapes to endure much longer heat treatment without J c degradation than the high-temperature method. Microscopic analysis also revealed that this method could obtain a clear boundary without a reaction layer or interdiffusion between a superconducting core and sheath metal.

  10. 一种避免低压隔离变压器合闸涌流的新型实用方法%The practical method to avoid switching inrush current of low-voltage isolation transformer

    Institute of Scientific and Technical Information of China (English)

    赵忠云; 田贵书

    2016-01-01

    介绍了变压器空载合闸励磁涌流产生机理,详细分析了利用软启动器空载合闸及分闸隔离变压器时避免合闸涌流及操作过电压的原理、方法,验证了该方法安全可靠、成本低、安装方便,值得推广。%The generating mechanism of no-load switching inrush current in transformer is introduced. This paper makes in-depth analysis of using soft starter with no-load closing and opening isolation transformer to avoid switching inrush current, principle and method of switching surge. It shows that the method has characteristics of safety and reliability, low cost and easy installation, which is worth promoting.

  11. Potential benefits and shortcomings of marine protected areas for small seabirds revealed using miniature tags

    Directory of Open Access Journals (Sweden)

    Sara M Maxwell

    2016-12-01

    Full Text Available Marine protected areas are considered important tools for protecting marine biodiversity, and animal tracking is a key way to determine if boundaries are effectively placed for protection of key marine species, including seabirds. We tracked chick-rearing brown noddies (Anous stolidus from the Dry Tortugas National Park in Florida USA in 2016 using 1.8 g Nanofix GPS tags (n = 10, making this the first time this species has ever been tracked. We determined movement parameters, such as flight speed, distance traveled and home range, and how birds used a complex of marine protected areas including the Dry Tortugas National Park which is largely no-take (i.e., no fishing or extraction permitted, and the Florida Keys National Marine Sanctuary, of which two Ecological Reserves totaling 517.9 km2 are no-take. Birds remained largely within marine protected areas, with 91.3% of birds’ locations and 58.8% of the birds’ total home range occurring within the MPAs, and 79.2% of birds’ locations and 18.2% of the birds’ total home range within no-take areas. However areas of probable foraging, indicated by locations where birds had high-residence time, were found within one of the MPAs only 64.7% of the time, and only 6.7% of those locations were in no-take areas. Birds traveled a mean straight line distance from the colony of 37.5 km, primarily using the region to the southwest of the colony where the shelf break and Loop Current occur. High-residence-time locations were found in areas of significantly higher sea surface temperature and closer to the shelf break than low residency locations. A sea surface temperature front occurs near the shelf edge, likely indicative of where Sargassum seaweed is entrained, providing habitat for forage species. Much of this region, however, falls outside the boundaries of the marine protected areas, and brown noddies and other species breeding in the Dry Tortugas may interact with fisheries via resource competition

  12. Assessing the role of seabirds in the ecology of influenza A viruses

    Science.gov (United States)

    Lang, Andrew S.; Lebarbenchon, Camille; Robertson, Gregory J.; Ramey, Andrew M.; Waldenström, Jonas; Wille, Michelle

    2016-01-01

    Wild waterbirds, specifically waterfowl, gulls, and shorebirds, are recognized as the primordial reservoir of influenza A viruses (IAVs). However, the role of seabirds, an abundant, diverse, and globally distributed group of birds, in the perpetuation and transmission of IAVs is less clear. Here we summarize published and publicly available data for influenza viruses in seabirds, which for the purposes of this study are defined as birds that exhibit a largely or exclusively pelagic lifestyle and exclude waterfowl, gulls, and shorebirds, and we review this collective dataset to assess the role of seabirds in the influenza A ecology. Since 1961, more than 40,000 samples have been collected worldwide from the seabirds considered here and screened, using a variety of techniques, for evidence of active or past IAV infection. From these data, the overall prevalence of active infection has been estimated to be very low; however, serological data provide evidence that some seabird species are more frequently exposed to IAVs. Sequence data for viruses from seabirds are limited, except for murres (common murre, Uria aalge, and thick-billed murre, Uria lomvia; family Alcidae) for which there are full or partial genome sequences available for more than 80 viruses. Characterization of these viruses suggests that murres are infected with Group 1 hemagglutinin subtype viruses more frequently as compared to Group 2 and also indicates that these northern, circumpolar birds are frequently infected by intercontinental reassortant viruses. Greater temporal and spatial sampling and characterization of additional viruses are required to better understand the role of seabirds in global IAV dynamics.

  13. Assessing the Role of Seabirds in the Ecology of Influenza A Viruses.

    Science.gov (United States)

    Lang, Andrew S; Lebarbenchon, Camille; Ramey, Andrew M; Robertson, Gregory J; Waldenström, Jonas; Wille, Michelle

    2016-05-01

    Wild waterbirds, specifically waterfowl, gulls, and shorebirds, are recognized as the primordial reservoir of influenza A viruses (IAVs). However, the role of seabirds, an abundant, diverse, and globally distributed group of birds, in the perpetuation and transmission of IAVs is less clear. Here we summarize published and publicly available data for influenza viruses in seabirds, which for the purposes of this study are defined as birds that exhibit a largely or exclusively pelagic lifestyle and exclude waterfowl, gulls, and shorebirds, and we review this collective dataset to assess the role of seabirds in the influenza A ecology. Since 1961, more than 40,000 samples have been collected worldwide from the seabirds considered here and screened, using a variety of techniques, for evidence of active or past IAV infection. From these data, the overall prevalence of active infection has been estimated to be very low; however, serological data provide evidence that some seabird species are more frequently exposed to IAVs. Sequence data for viruses from seabirds are limited, except for murres (common murre, Uria aalge, and thick-billed murre, Uria lomvia; family Alcidae) for which there are full or partial genome sequences available for more than 80 viruses. Characterization of these viruses suggests that murres are infected with Group 1 hemagglutinin subtype viruses more frequently as compared to Group 2 and also indicates that these northern, circumpolar birds are frequently infected by intercontinental reassortant viruses. Greater temporal and spatial sampling and characterization of additional viruses are required to better understand the role of seabirds in global IAV dynamics.

  14. Patterns of seabird and marine mammal carcass deposition along the central California coast, 1980-1986

    Science.gov (United States)

    Bodkin, J.L.; Jameson, R.

    1991-01-01

    At monthly intervals from February 1980 through December 1986, a 14.5-km section of central California coastline was systematically surveyed for beach-cast carcasses of marine birds and mammlas. Five hundred and fifty-four bird carcasses and 194 marine mammal carcasses were found. Common murres, western grebes, and Brandt's cormorants composed 45% of the bird total. California sea lions, sea otters, and harbor seals composed 90% of the mammal total. Several factors appeared to affect patterns of carcass deposition. The El Nino-Southern Oscillation (ENSO) of 1982-1983 was the dominate influence in terms of interannual variation in carcassdeposition. During this ENSO, 56% of the seabirds and 48% of the marine mammals washed ashore. Patterns of intra-annual variation were species specificand were related to animal migration patterns, reproduction, and seasonal changes in weather. Nearshore currents and winds influenced the general area of carcass deposition, while beach subtrate type and local patterns of san deposition influenced the location of carcass carcass deposition on a smaller spatial scale. Weekly surveys along a 1.1-km section of coastline indicated that 62% of bird carcasses and 41% of mammal carcasses remained on the beach less than 9 days. Cause of death determined for only 8% of the carcasses. Oiling was the most common indication of cause of death in birds (6%). Neonates composed 8% of all mammal carcasses.

  15. Adverse foraging conditions may impact body mass and survival of a high Arctic seabird

    Science.gov (United States)

    Harding, A.M.A.; Welcker, J.; Steen, H.; Hamer, K.C.; Kitaysky, A.S.; Fort, J.; Talbot, S.L.; Cornick, L.A.; Karnovsky, N.J.; Gabrielsen, G.W.; Gremillet, D.

    2011-01-01

    Tradeoffs between current reproduction and future survival are widely recognized, but may only occur when food is limited: when foraging conditions are favorable, parents may be able to reproduce without compromising their own survival. We investigated these tradeoffs in the little auk (Alle alle), a small seabird with a single-egg clutch. During 2005-2007, we examined the relationship between body mass and survival of birds breeding under contrasting foraging conditions at two Arctic colonies. We used corticosterone levels of breeding adults as a physiological indicator of the foraging conditions they encountered during each reproductive season. We found that when foraging conditions were relatively poor (as reflected in elevated levels of corticosterone), parents ended the reproductive season with low body mass and suffered increased post-breeding mortality. A positive relationship between body mass and post-breeding survival was found in one study year; light birds incurred higher survival costs than heavy birds. The results of this study suggest that reproducing under poor foraging conditions may affect the post-breeding survival of long-lived little auks. They also have important demographic implications because even a small change in adult survival may have a large effect on populations of long-lived species. ?? 2011 Springer-Verlag.

  16. Assessing incidental bycatch of seabirds in Norwegian coastal commercial fisheries: Empirical and methodological lessons

    Directory of Open Access Journals (Sweden)

    Kirstin Fangel

    2015-07-01

    Full Text Available With diminishing seabird populations and little knowledge on incidental bycatch in fisheries in the Northeast Atlantic, this study aimed to screen seabird bycatch in Norwegian coastal fisheries in 2009. The purpose was to 1 quantify magnitude of seabird bycatch rates and estimate total bycatch from the entire fleet by different estimators 2 evaluate data from an access point survey against monitoring data from a reference fleet as methods for collecting data on bycatch mortality of seabirds and 3 give advice on further bycatch studies. The study focused on three small-vessel fisheries (11 000 birds estimated caught. The black guillemot Cepphus gryllealso stood out as a numerous victim, constituting almost two thirds of the >3000 birds estimated to have drowned in lumpfish gillnets. The two methods were both considered to hold merit and yielded approximately similar estimates of the bycatch in the coastal cod fisheries, however BPUE differs. Further studies are recommended especially on the lumpfish gillnet and Greenland halibut longline fisheries and on temporal and spatial variations in bycatch. More studies are also needed to model effects on seabirds at the population level.

  17. Geographical patterns of seabird attendance to a research trawler along the Iberian Mediterranean coast

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    Pere Abelló

    2003-07-01

    Full Text Available The attendance of seabirds to a research trawler along the Mediterranean coast of the Iberian Peninsula was monitored during six demersal surveys (MEDITS project. Cruises were performed in late spring during the period 1994-1999. Twenty seabird species were recorded, including both breeders and migrants. The four most common species behind the boat were local breeders, namely the Balearic shearwater Puffinus mauretanicus, Cory´s shearwater Calonectris diomedea, Audouin´s gull Larus audouinii and the yellow-legged gull Larus cachinnans. Most seabirds made use of trawler discards to some extent, with the exception of the Puffin Fratercula arctica. Geographically consistent patterns were identified in the six years surveyed. Seabirds were most abundant along the eastern coast of Iberia, especially off the Ebro Delta and around the Columbretes Islands, coinciding with one of the major areas of primary productivity and one of the largest trawling fleets in the western Mediterranean. The location of the main seabird colonies also influenced the distribution of breeders.

  18. Biogeography of top predators - seabirds and cetaceans - along four latitudinal transects in the Atlantic Ocean

    Science.gov (United States)

    Jungblut, Simon; Nachtsheim, Dominik A.; Boos, Karin; Joiris, Claude R.

    2017-07-01

    The distribution, abundance, and species assemblage of top predators - seabirds and cetaceans - can be correlated to water masses as defined by hydrological parameters. In comparison to other oceans, information about the structuring effects of water masses on top predators in the Atlantic Ocean is limited. The present study aims 1) to provide baseline distributional data of top predators for future comparisons, for instance in the course of climate change, and 2) to test how water masses and seasons affect distributional patterns of seabirds and cetaceans in the temperate and tropical Atlantic. During four trans-equatorial expeditions of the RV Polarstern between 2011 and 2014, at-sea observation data of seabirds, cetaceans and other megafauna were collected. Counts of top predators were generally low in the surveyed regions. Statistical analyses for the eight most abundant seabird species and the pooled number of cetaceans revealed water masses and seasons to account for differences in counts and thus also distribution. In most cases, borders between water masses were not very distinct due to gradual changes in surface water properties. Thus, top predator counts were correlated to water masses but, in contrast to polar waters, not strongly linked to borders between water masses. Additional factors, e.g. distance to locally productive areas (upwelling), competition effects, and seabird associations to prey-accumulating subsurface predators may be similarly important in shaping distributional patterns of top predators in the tropical and temperate Atlantic, but could not be specifically tested for here.

  19. Marine wind farms - seabirds, white-tailed eagles, Eurasian eagle-owl and waders. A screening of potential conflict areas; Offshore vindenergianlegg - sjoefugl, havoern, hubro og vadere. En screening av potensielle konfliktomraader

    Energy Technology Data Exchange (ETDEWEB)

    Christensen-Dalsgaard, S.; Lorentsen, S.-H.; Dahl, E.L.; Follestad, A.; Hanssen, F.O.; Systad, G.H.

    2010-06-15

    The objective of the present study was to develop a decision-relevant, large-scale screening tool for areas that may be suitable for the establishment of offshore wind power plants. The surveyed area ranged from the Swedish border in the south (North Sea/Skagerrak) to the northern tip of Andoeya (North Sea). Marine wind farms are a relatively new element in European waters, and at present there have been few investigations carried out to study their short- and long-term environmental effects. While there have been several studies to identify environmental impacts of wind farms in other countries, there is currently only one such study in Norway, on the island of Smoela. So far, four mechanisms have been emphasized with regard to the impact of wind farms on birds: 1) mortality resulting from collisions with wind turbines (tower and wings), 2) avoidance due to interference from installations in operation and from the activity associated with the construction of the windfarm; 3) loss and change of habitat, through habitat degradation and fragmentation, and 4) barrier effects, which may increase the flight distance and increase the birds' energy demands. In this report, we have chosen to use a methodology that was developed to evaluate seabird vulnerability to marine wind farms in German waters. This method provides a species-specific vulnerability index based on nine factors: flight maneuverability, flight altitude, percentage of time flying, nocturnal flight activity, sensitivity towards disturbance by ship/helicopter traffic, flexibility in habitat use, biogeographical population size, adult survival rate and conservation status. Combined with a measure of density or relative proportion of the relevant species in an area, a wind farm sensitivity index (WSI) is created. The WSI can be summed for all species found in the area at different times of the year to give a total WSI for seabirds. The existing data for seabirds in winter and in the breeding season was of

  20. Personality, foraging and fitness consequences in a long lived seabird.

    Directory of Open Access Journals (Sweden)

    Samantha C Patrick

    Full Text Available While personality differences in animals are defined as consistent behavioural variation between individuals, the widely studied field of foraging specialisation in marine vertebrates has rarely been addressed within this framework. However there is much overlap between the two fields, both aiming to measure the causes and consequences of consistent individual behaviour. Here for the first time we use both a classic measure of personality, the response to a novel object, and an estimate of foraging strategy, derived from GPS data, to examine individual personality differences in black browed albatross and their consequences for fitness. First, we examine the repeatability of personality scores and link these to variation in foraging habitat. Bolder individuals forage nearer the colony, in shallower regions, whereas shyer birds travel further from the colony, and fed in deeper oceanic waters. Interestingly, neither personality score predicted a bird's overlap with fisheries. Second, we show that both personality scores are correlated with fitness consequences, dependent on sex and year quality. Our data suggest that shyer males and bolder females have higher fitness, but the strength of this relationship depends on year quality. Females who forage further from the colony have higher breeding success in poor quality years, whereas males foraging close to the colony always have higher fitness. Together these results highlight the potential importance of personality variation in seabirds and that the fitness consequences of boldness and foraging strategy may be highly sex dependent.

  1. The sub-annual breeding cycle of a tropical seabird.

    Science.gov (United States)

    Reynolds, S James; Martin, Graham R; Dawson, Alistair; Wearn, Colin P; Hughes, B John

    2014-01-01

    Breeding periodicity allows organisms to synchronise breeding attempts with the most favourable ecological conditions under which to raise offspring. For most animal species, ecological conditions vary seasonally and usually impose an annual breeding schedule on their populations; sub-annual breeding schedules will be rare. We use a 16-year dataset of breeding attempts by a tropical seabird, the sooty tern (Onychoprion fuscatus), on Ascension Island to provide new insights about this classical example of a population of sub-annually breeding birds that was first documented in studies 60 years previously on the same island. We confirm that the breeding interval of this population has remained consistently sub-annual. By ringing >17,000 birds and re-capturing a large sample of them at equivalent breeding stages in subsequent seasons, we reveal for the first time that many individual birds also consistently breed sub-annually (i.e. that sub-annual breeding is an individual as well as a population breeding strategy). Ascension Island sooty terns appear to reduce their courtship phase markedly compared with conspecifics breeding elsewhere. Our results provide rare insights into the ecological and physiological drivers of breeding periodicity, indicating that reduction of the annual cycle to just two life-history stages, breeding and moult, is a viable life-history strategy and that moult may determine the minimum time between breeding attempts.

  2. An evaluation of oil spill responses for offshore oil production projects in Newfoundland and Labrador, Canada: Implications for seabird conservation.

    Science.gov (United States)

    Fraser, Gail S; Racine, Vincent

    2016-06-15

    Seabirds are vulnerable to oil pollution, particularly in cold-water regions. We investigated the response of small spills (oil production operations Environment Canada requested monitoring and mitigation of small spills potentially impacting seabird populations; suggestions supported by two independent reviews. An industry spill response plan states that operators would collect systematic observations on spills and deploy countermeasures where possible. Operators' spill reports were obtained under an Access to Information request. There were 220 daytime spills with sheens (out of 381 spills; 1997-2010). Of these, six reported time to oil dispersion and eleven the presence or absence of seabirds. Industry self-reporting has not permitted an evaluation of the impact of chronic oil spills on seabirds. We recommend that independent observers be placed on platforms to systematically collect data on spills and seabirds.

  3. Qualitative and numerical investigations of the impact of a novel pathogen on a seabird colony

    Energy Technology Data Exchange (ETDEWEB)

    O' Regan, S M; O' Callaghan, M J A; Pokrovskii, A V [Department of Applied Mathematics, Aras na Laoi, University College Cork (Ireland); Kelly, T C [Department of Zoology, Ecology and Plant Science, Distillery Fields, North Mall, University College Cork (Ireland); Korobeinikov, A [MACSI, Department of Mathematics and Statistics, University of Limerick, Limerick (Ireland)], E-mail: s.m.oregan@student.ucc.ie

    2008-11-01

    Understanding the dynamics of novel pathogens in dense populations is crucial to public and veterinary health as well as wildlife ecology. Seabirds live in crowded colonies numbering several thousands of individuals. The long-term dynamics of avian influenza H5N1 virus in a seabird colony with no existing herd immunity are investigated using sophisticated mathematical techniques. The key characteristics of seabird population biology and the H5N1 virus are incorporated into a Susceptible-Exposed-Infected-Recovered (SEIR) model. Using the theory of integral manifolds, the SEIR model is reduced to a simpler system of two differential equations depending on the infected and recovered populations only, termed the IR model. The results of numerical experiments indicate that the IR model and the SEIR model are in close agreement. Using Lyapunov's direct method, the equilibria of the SEIR and the IR models are proven to be globally asymptotically stable in the positive quadrant.

  4. Qualitative and numerical investigations of the impact of a novel pathogen on a seabird colony

    Science.gov (United States)

    O'Regan, S. M.; Kelly, T. C.; Korobeinikov, A.; O'Callaghan, M. J. A.; Pokrovskii, A. V.

    2008-11-01

    Understanding the dynamics of novel pathogens in dense populations is crucial to public and veterinary health as well as wildlife ecology. Seabirds live in crowded colonies numbering several thousands of individuals. The long-term dynamics of avian influenza H5N1 virus in a seabird colony with no existing herd immunity are investigated using sophisticated mathematical techniques. The key characteristics of seabird population biology and the H5N1 virus are incorporated into a Susceptible-Exposed-Infected-Recovered (SEIR) model. Using the theory of integral manifolds, the SEIR model is reduced to a simpler system of two differential equations depending on the infected and recovered populations only, termed the IR model. The results of numerical experiments indicate that the IR model and the SEIR model are in close agreement. Using Lyapunov's direct method, the equilibria of the SEIR and the IR models are proven to be globally asymptotically stable in the positive quadrant.

  5. Seasonal Variation in the Abundance of Seabirds in Areas of Mariculture

    Directory of Open Access Journals (Sweden)

    Branco Joaquim Olinto

    2001-01-01

    Full Text Available Mariculture has emerged as a complementary income for small fishermen along the coast of the state of Santa Catarina, Brazil, causing significant alterations in the coastal landscape and creating a new substratum seabirds. From March 1998 to February 1999, 48 censuses were carried out at four sample times, registering an average annual occurrence of 4448.7 birds, distributed among five seabird species. Laridae dominated in diversity and abundance, contributing with 98.1% of the birds recorded. The number of birds per float varied depending on the time of day and season of the year, showing an average of 2.09/1. Seabirds use the mariculture area as a place to rest, to clean their feathers and to overnight.

  6. Avoiding health information.

    Science.gov (United States)

    Barbour, Joshua B; Rintamaki, Lance S; Ramsey, Jason A; Brashers, Dale E

    2012-01-01

    This study investigated why and how individuals avoid health information to support the development of models of uncertainty and information management and offer insights for those dealing with the information and uncertainty inherent to health and illness. Participants from student (n = 507) and community (n = 418) samples reported that they avoided health information to (a) maintain hope or deniability, (b) resist overexposure, (c) accept limits of action, (d) manage flawed information, (e) maintain boundaries, and (f) continue with life/activities. They also reported strategies for avoiding information, including removing or ignoring stimuli (e.g., avoiding people who might provide health advice) and controlling conversations (e.g., withholding information, changing the subject). Results suggest a link between previous experience with serious illness and health information avoidance. Building on uncertainty management theory, this study demonstrated that health information avoidance is situational, relatively common, not necessarily unhealthy, and may be used to accomplish multiple communication goals.

  7. Predicting seasonal variations in coastal seabird habitats in the English Channel and the Bay of Biscay

    Science.gov (United States)

    Virgili, A.; Lambert, C.; Pettex, E.; Dorémus, G.; Van Canneyt, O.; Ridoux, V.

    2017-07-01

    Seabirds, like all animals, have to live in suitable habitats to fulfil their energetic needs for both somatic and reproductive growth and maintenance. Apart from migration trips, all coastal seabirds are linked to the coast, because they need to return daily to land for resting or breeding. Their use of marine habitats strongly depends on their biology, but also on environmental conditions, and can be described using habitat models. This study aimed to: (1) identify the processes that mostly influence seabird distributions along the coasts of the English Channel and the Bay of Biscay; (2) determine seasonal variations of these processes, (3) provide prediction maps that describe the species distributions. We collected data of coastal seabird sightings from aerial surveys carried out in the English Channel and the eastern North Atlantic in the winter 2011-2012 and summer 2012. We classified seabirds into morphological groups and described their habitats using physiographic and oceanographic variables in Generalised Additive Models (GAMs). Finally, we produced maps of predicted distributions by season for each group. The distributions of coastal seabirds were essentially determined by the distance to the nearest coast, with a weaker influence of oceanographic variables. The nature of the substrate, sand or rock, combined with the timing of reproduction, also contributed to determine seasonal at-sea distributions for some species. The highest densities were predicted near the coast, particularly in bays and estuaries for strictly coastal species with possible variations depending on the season. From this study, we were able to predict the seasonal distribution of the studied species according to varying environmental parameters that changed over time, allowing us to understand better their behaviour and ecology.

  8. Cliff-nesting seabirds influence production and sediment chemistry of lakes situated above their colony.

    Science.gov (United States)

    Hargan, K E; Michelutti, N; Coleman, K; Grooms, C; Blais, J M; Kimpe, L E; Gilchrist, G; Mallory, M; Smol, J P

    2017-01-15

    Seabirds that congregate in large numbers during the breeding season concentrate marine-derived nutrients to their terrestrial nesting sites, and these nutrients disperse and enhance production in nearby terrestrial, freshwater and marine ecosystems. In the Canadian Arctic, large seabird colonies (>100,000 breeding pairs) nest on cliff faces that drain directly in the ocean, ultimately returning the nutrients back to the marine environment from which they were derived. However, strong winds blowing up cliff faces could transport nutrients up in elevation and onto surrounding terrestrial and aquatic environments. Here, we assess the degree to which seabird nutrients and metals have been delivered to coastal lakes near Hudson Strait (Nunavut, Canada) over the past century. Three lakes located at a higher elevation and increasing distance from a thick-billed murre (Uria lomvia) colony (~400,000 breeding pairs) were sampled for surface water chemistry. In addition, algal assemblages, nitrogen isotopes, and metal/metalloids were analyzed in four dated sediment cores. Elevated nutrients and major ions, as well as an enriched δ(15)N signature in the sediment cores, were measured in the lake lakes >1km from the seabird colony. In contrast, similar oligotrophic and benthic diatom assemblages were identified in all three lakes, suggesting that diatoms were not influenced by enhanced nutrient inputs in this Arctic environment. Chemical tracers (e.g., total mercury) and algal assemblages in the lake near the colony suggest climate warming since ~1950 was the most likely driver of limnological changes, but this effect was muted in the more distant lakes. These pronounced changes in the seabird-impacted lake suggest that, with warming air temperatures and diminished lake ice cover, longer growing seasons may allow for aquatic organisms to more fully exploit the seabird nutrient subsidies.

  9. Cognitive avoidance in phobia

    NARCIS (Netherlands)

    Brosschot, J.F.; Kindt, M.

    1998-01-01

    Investigated the stage in which the bias changed into avoidance and whether cognitive avoidance of threat is restricted to information that refers to the anxiety response as opposed to the threatening stimulus. Therefore, 37 spider phobics (mean age 31 yrs) and 34 controls (mean age 38 yrs) were

  10. Seabird guano fertilizes Baltic Sea littoral food webs.

    Directory of Open Access Journals (Sweden)

    Karine Gagnon

    Full Text Available Nutrient enrichment in coastal marine systems can have profound impacts on trophic networks. In the Baltic Sea, the population of Great Cormorant (Phalacrocorax carbo sinensis has increased nearly exponentially since the mid-1990 s, and colonies of these seabirds can be important sources of nitrogen enrichment for nearby benthic communities due to guano runoff. In this study we used stable isotope analyses and diet mixing models to determine the extent of nitrogen enrichment from cormorant colonies, as well as to examine any possible changes in herbivore diet preferences due to enrichment. We found significantly higher levels of δ(15N in samples from colony islands than control islands for producers (the dominant macroalga Fucus vesiculosus, filamentous algae, and periphyton and herbivores, as well as a positive correlation between enrichment and nest density in colony sites. We also found that enrichment increased over the breeding season of the cormorants, with higher enrichment in late summer than early summer. While the amount of total nitrogen did not differ between colony and control sites, the amount of guano-based nitrogen in algae was >50% in most sites, indicating high nitrogen enrichment from colonies. Herbivores (the isopod Idotea balthica and the gastropod Theodoxus fluviatilis preferred feeding upon the dominant macroalga Fucus vesiculosus rather than on filamentous algae or periphyton in both control and colony, and there was a significant increase in periphyton consumption near colony sites. Overall, guano from cormorant colonies seems to have effects on both producers and herbivores, as well as the potential to modify algae-herbivore interactions.

  11. Seabird Guano Fertilizes Baltic Sea Littoral Food Webs

    Science.gov (United States)

    Gagnon, Karine; Rothäusler, Eva; Syrjänen, Anneli; Yli-Renko, Maria; Jormalainen, Veijo

    2013-01-01

    Nutrient enrichment in coastal marine systems can have profound impacts on trophic networks. In the Baltic Sea, the population of Great Cormorant (Phalacrocorax carbo sinensis) has increased nearly exponentially since the mid-1990s, and colonies of these seabirds can be important sources of nitrogen enrichment for nearby benthic communities due to guano runoff. In this study we used stable isotope analyses and diet mixing models to determine the extent of nitrogen enrichment from cormorant colonies, as well as to examine any possible changes in herbivore diet preferences due to enrichment. We found significantly higher levels of δ15N in samples from colony islands than control islands for producers (the dominant macroalga Fucus vesiculosus, filamentous algae, and periphyton) and herbivores, as well as a positive correlation between enrichment and nest density in colony sites. We also found that enrichment increased over the breeding season of the cormorants, with higher enrichment in late summer than early summer. While the amount of total nitrogen did not differ between colony and control sites, the amount of guano-based nitrogen in algae was >50% in most sites, indicating high nitrogen enrichment from colonies. Herbivores (the isopod Idotea balthica and the gastropod Theodoxus fluviatilis) preferred feeding upon the dominant macroalga Fucus vesiculosus rather than on filamentous algae or periphyton in both control and colony, and there was a significant increase in periphyton consumption near colony sites. Overall, guano from cormorant colonies seems to have effects on both producers and herbivores, as well as the potential to modify algae-herbivore interactions. PMID:23593452

  12. Contaminants in tracked seabirds showing regional patterns of marine pollution.

    Science.gov (United States)

    Ito, Atsuo; Yamashita, Rei; Takada, Hideshige; Yamamoto, Takashi; Shiomi, Kozue; Zavalaga, Carlos; Abe, Tomoya; Watanabe, Shinichi; Yamamoto, Maki; Sato, Katsufumi; Kohno, Hiroyoshi; Yoda, Ken; Iida, Tomohiko; Watanuki, Yutaka

    2013-07-16

    Ocean-scale monitoring of pollution is challenging. Seabirds are useful indicators because they travel over a broad foraging range. Nevertheless, this coarse spatial resolution is not fine enough to discriminate pollution in a finer scale. Previous studies have demonstrated that pollution levels are higher in the Sea of Japan and South and East China Seas than the Northen Pacific Ocean. To test these findings in a wide-ranging animal, we tracked streaked shearwaters (Calonectris leucomelas) from four islands in Japan using global positioning system (GPS) and measured persistent organic pollutants (POPs) in the oil of their preen glands. The POPs did not change during 6 to 21 days when birds from Awashima were foraging only in the Sea of Japan, while it increased when they crossed to the Pacific through the Tsugaru Strait and foraged along the eastern coast of Hokkaido where industrial cities occur. These results indicate that POPs in the oil reflect relatively short-term exposure. Concentrations of POPs displayed greater variation among regions. Total polychlorinated biphenyls were highest in birds foraging in a small area of the semiclosed Seto Inland Sea surrounded by urbanized coast, p,p'-dichlorodiphenyltrichloroethane (DDT) was highest in birds foraging in the East China Sea, and total hexachlorocyclohexanes were highest in birds foraging in the Sea of Japan. All were lowest in birds foraging in the Pacific. This distribution of POPs concentration partly agrees with previous findings based on mussels, fish, and seawater and possibly reflects the mobility and emission sources of each type of POP. These results highlight the importance of information on the foraging area of highly mobile top predators to make them more effective monitors of regional marine pollution.

  13. Combined bio-logging and stable isotopes reveal individual specialisations in a benthic coastal seabird, the Kerguelen shag.

    Science.gov (United States)

    Camprasse, Elodie C M; Cherel, Yves; Arnould, John P Y; Hoskins, Andrew J; Bost, Charles-André

    2017-01-01

    Individual specialisations, which involve the repetition of specific behaviours or dietary choices over time, have been suggested to benefit animals by avoiding competition with conspecifics and increasing individual foraging efficiency. Among seabirds, resident and benthic species are thought to be good models to study inter-individual variation as they repetitively exploit the same environment. We investigated foraging behaviour, isotopic niche and diet in the Kerguelen shag Phalacrocorax verrucosus during both the incubation and chick-rearing periods for the same individuals to determine the effect of sex, breeding stage, body mass and morphometrics on mean foraging metrics and their consistency. There were large differences between individuals in foraging behaviour and consistency, with strong individual specialisations in dive depths and heading from the colony. Stable isotopes revealed specialisations in feeding strategies, across multiple temporal scales. Specifically, individuals showed medium term specialisations in feeding strategies during the breeding season, as well as long-term consistency. A clustering analysis revealed 4 different foraging strategies displaying significantly different δ15N values and body masses. There were no sex or stage biases to clusters and individuals in different clusters did not differ in their morphology. Importantly, the results suggest that the different strategies emphasized were related to individual prey preferences rather than intrinsic characteristics.

  14. Combined bio-logging and stable isotopes reveal individual specialisations in a benthic coastal seabird, the Kerguelen shag

    Science.gov (United States)

    Cherel, Yves; Hoskins, Andrew J.

    2017-01-01

    Individual specialisations, which involve the repetition of specific behaviours or dietary choices over time, have been suggested to benefit animals by avoiding competition with conspecifics and increasing individual foraging efficiency. Among seabirds, resident and benthic species are thought to be good models to study inter-individual variation as they repetitively exploit the same environment. We investigated foraging behaviour, isotopic niche and diet in the Kerguelen shag Phalacrocorax verrucosus during both the incubation and chick-rearing periods for the same individuals to determine the effect of sex, breeding stage, body mass and morphometrics on mean foraging metrics and their consistency. There were large differences between individuals in foraging behaviour and consistency, with strong individual specialisations in dive depths and heading from the colony. Stable isotopes revealed specialisations in feeding strategies, across multiple temporal scales. Specifically, individuals showed medium term specialisations in feeding strategies during the breeding season, as well as long-term consistency. A clustering analysis revealed 4 different foraging strategies displaying significantly different δ15N values and body masses. There were no sex or stage biases to clusters and individuals in different clusters did not differ in their morphology. Importantly, the results suggest that the different strategies emphasized were related to individual prey preferences rather than intrinsic characteristics. PMID:28264057

  15. Integrating population and genetic monitoring to understand changes in the abundance of a threatened seabird

    Science.gov (United States)

    Catalina Vásquez-Carrillo; R. William Henry; Laird Henkel; M. Zachariah. Peery

    2013-01-01

    Population monitoring programs for threatened species are rarely designed to disentangle the effects of movements from changes in birth and death rates on estimated trends in abundance. Here, we illustrate how population and genetic monitoring can be integrated to understand the cause of large changes in the abundance of a threatened species of seabird, the Marbled...

  16. Biodiversity offsets: a cost-effective interim solution to seabird bycatch in fisheries?

    Directory of Open Access Journals (Sweden)

    Sean Pascoe

    Full Text Available The concept of biodiversity offsets is well established as an approach to environmental management. The concept has been suggested for environmental management in fisheries, particularly in relation to the substantial numbers of non-target species--seabirds in particular--caught and killed as incidental bycatch during fishing activities. Substantial areas of fisheries are being closed to protect these species at great cost to the fishing industry. However, other actions may be taken to offset the impact of fishing on these populations at lower cost to the fishing industry. This idea, however, has attracted severe criticism largely as it does not address the underlying externality problems created by the fishing sector, namely seabird fishing mortality. In this paper, we re-examine the potential role of compensatory mitigation as a fisheries management tool, although from the perspective of being an interim management measure while more long-lasting solutions to the problem are found. We re-model an example previously examined by both proponents and opponents of the approach, namely the cost effectiveness of rodent control relative to fishery area closures for the conservation of a seabird population adversely affected by an Australian tuna fishery. We find that, in the example being examined, invasive rodent eradication is at least 10 times more cost effective than area closures. We conclude that, while this does not solve the actual bycatch problem, it may provide breathing space for both the seabird species and the industry to find longer term means of reducing bycatch.

  17. Serological evidence for the circulation of flaviviruses in seabird populations of the western Indian Ocean.

    Science.gov (United States)

    Jaeger, A; Lecollinet, S; Beck, C; Bastien, M; Le Corre, M; Dellagi, K; Pascalis, H; Boulinier, T; Lebarbenchon, C

    2016-02-01

    Birds play a central role in the epidemiology of several flaviviruses of concern for public and veterinary health. Seabirds represent the most abundant and widespread avifauna in the western Indian Ocean and may play an important role as host reservoirs and spreaders of arthropod-borne pathogens such as flaviviruses. We report the results of a serological investigation based on blood samples collected from nine seabird species from seven islands in the Indian Ocean. Using a commercial competitive enzyme-linked immunosorbent assay directed against the prototypic West Nile flavivirus, antibodies against flaviviruses were detected in the serum of 47 of the 855 seabirds tested. They were detected in bird samples from three islands and from four bird species. Seroneutralization tests on adults and chicks suggested that great frigatebirds (Fregata minor) from Europa were infected by West Nile virus during their non-breeding period, and that Usutu virus probably circulated within bird colonies on Tromelin and on Juan de Nova. Real-time polymerase chain reactions performed on bird blood samples did not yield positive results precluding the genetic characterization of flavivirus using RNA sequencing. Our findings stress the need to further investigate flavivirus infections in arthropod vectors present in seabird colonies.

  18. Seabird aggregative patterns: a new tool for offshore wind energy risk assessment.

    Science.gov (United States)

    Christel, Isadora; Certain, Grégoire; Cama, Albert; Vieites, David R; Ferrer, Xavier

    2013-01-15

    The emerging development of offshore wind energy has raised public concern over its impact on seabird communities. There is a need for an adequate methodology to determine its potential impacts on seabirds. Environmental Impact Assessments (EIAs) are mostly relying on a succession of plain density maps without integrated interpretation of seabird spatio-temporal variability. Using Taylor's power law coupled with mixed effect models, the spatio-temporal variability of species' distributions can be synthesized in a measure of the aggregation levels of individuals over time and space. Applying the method to a seabird aerial survey in the Ebro Delta, NW Mediterranean Sea, we were able to make an explicit distinction between transitional and feeding areas to define and map the potential impacts of an offshore wind farm project. We use the Ebro Delta study case to discuss the advantages of potential impacts maps over density maps, as well as to illustrate how these potential impact maps can be applied to inform on concern levels, optimal EIA design and monitoring in the assessment of local offshore wind energy projects.

  19. Timing of ice retreat alters seabird abundances and distributions in the southeast Bering Sea.

    Science.gov (United States)

    Renner, Martin; Salo, Sigrid; Eisner, Lisa B; Ressler, Patrick H; Ladd, Carol; Kuletz, Kathy J; Santora, Jarrod A; Piatt, John F; Drew, Gary S; Hunt, George L

    2016-09-01

    Timing of spring sea-ice retreat shapes the southeast Bering Sea food web. We compared summer seabird densities and average bathymetry depth distributions between years with early (typically warm) and late (typically cold) ice retreat. Averaged over all seabird species, densities in early-ice-retreat-years were 10.1% (95% CI: 1.1-47.9%) of that in late-ice-retreat-years. In early-ice-retreat-years, surface-foraging species had increased numbers over the middle shelf (50-150 m) and reduced numbers over the shelf slope (200-500 m). Pursuit-diving seabirds showed a less clear trend. Euphausiids and the copepod Calanus marshallae/glacialis were 2.4 and 18.1 times less abundant in early-ice-retreat-years, respectively, whereas age-0 walleye pollock Gadus chalcogrammus near-surface densities were 51× higher in early-ice-retreat-years. Our results suggest a mechanistic understanding of how present and future changes in sea-ice-retreat timing may affect top predators like seabirds in the southeastern Bering Sea.

  20. Marine distribution of arctic seabirds over six decades: changes and conservation applications

    DEFF Research Database (Denmark)

    Wong, SNP; Johansen, Kasper Lambert; Lieske, DJ

    Climate change is causing rapid changes in Arctic marine ecosystems and understanding its impacts on wildlife is critical for conservation management, especially as the decline in sea ice leads to increased development and vessel traffic. The Arctic supports hundreds of millions of seabirds, which...

  1. 77 FR 73989 - Takes of Marine Mammals Incidental to Specified Activities; Seabird and Pinniped Research...

    Science.gov (United States)

    2012-12-12

    ... IHA (77 FR 59377, September 27, 2012), as behavioral modification. Mitigation In order to issue an... species may exhibit behavioral modifications, including temporarily vacating the area during the seabird... causing disruption of behavioral patterns, including, but not limited to, migration, breathing,...

  2. Restoring piscivorous fish populations in the Laurentian Great Lakes causes seabird dietary change

    Science.gov (United States)

    Hebert, C.E.; Weseloh, D.V.C.; Idrissi, A.; Arts, M.T.; O'Gorman, R.; Gorman, O.T.; Locke, B.; Madenjian, C.P.; Roseman, E.F.

    2008-01-01

    Ecosystem change often affects the structure of aquatic communities thereby regulating how much and by what pathways energy and critical nutrients flow through food webs. The availability of energy and essential nutrients to top predators such as seabirds that rely on resources near the water's surface will be affected by changes in pelagic prey abundance. Here, we present results from analysis of a 25-year data set documenting dietary change in a predatory seabird from the Laurentian Great Lakes. We reveal significant declines in trophic position and alterations in energy and nutrient flow over time. Temporal changes in seabird diet tracked decreases in pelagic prey fish abundance. As pelagic prey abundance declined, birds consumed less aquatic prey and more terrestrial food. This pattern was consistent across all five large lake ecosystems. Declines in prey fish abundance may have primarily been the result of predation by stocked piscivorous fishes, but other lake-specific factors were likely also important. Natural resource management activities can have unintended consequences for nontarget ecosystem components. Reductions in pelagic prey abundance have reduced the capacity of the Great Lakes to support the energetic requirements of surface-feeding seabirds. In an environment characterized by increasingly limited pelagic fish resources, they are being offered a Hobsonian choice: switch to less nutritious terrestrial prey or go hungry. ?? 2008 by the Ecological Society of America.

  3. No evidence of extra-pair paternity in a colonial seabird, the common tern (Sterna hirundo)

    DEFF Research Database (Denmark)

    Griggio, M.; Matessi, Giuliano; Marin, G.

    2004-01-01

    The incidence of extra-pair paternity and egg dumping was investigated in a colony of common terns (Sterna hirundo), a colonial seabird, in the Venetian lagoon. Ten families were sampled and multilocus DNA fingerprinting analysis was performed. No indication of extra-pair paternity or egg dumping...

  4. Seabird, fish, marine mammal and oceanography coordinated investigations (SMMOCI) in the Pribilof Islands, Alaska, July 2005

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We conducted a survey of seabirds, fishes, marine mammals and oceanographic conditions near the Pribilof Islands, Alaska (Fig. 1) from the M/V Tiˆglaˆx during 20-26...

  5. Contribution of Arctic seabird-colony ammonia to atmospheric particles and cloud-albedo radiative effect

    Science.gov (United States)

    Croft, B.; Wentworth, G. R.; Martin, R. V.; Leaitch, W. R.; Murphy, J. G.; Murphy, B. N.; Kodros, J. K.; Abbatt, J. P. D.; Pierce, J. R.

    2016-11-01

    The Arctic region is vulnerable to climate change and able to affect global climate. The summertime Arctic atmosphere is pristine and strongly influenced by natural regional emissions, which have poorly understood climate impacts related to atmospheric particles and clouds. Here we show that ammonia from seabird-colony guano is a key factor contributing to bursts of newly formed particles, which are observed every summer in the near-surface atmosphere at Alert, Nunavut, Canada. Our chemical-transport model simulations indicate that the pan-Arctic seabird-influenced particles can grow by sulfuric acid and organic vapour condensation to diameters sufficiently large to promote pan-Arctic cloud-droplet formation in the clean Arctic summertime. We calculate that the resultant cooling tendencies could be large (about -0.5 W m-2 pan-Arctic-mean cooling), exceeding -1 W m-2 near the largest seabird colonies due to the effects of seabird-influenced particles on cloud albedo. These coupled ecological-chemical processes may be susceptible to Arctic warming and industrialization.

  6. Threat of plastic pollution to seabirds is global, pervasive, and increasing.

    Science.gov (United States)

    Wilcox, Chris; Van Sebille, Erik; Hardesty, Britta Denise

    2015-09-22

    Plastic pollution in the ocean is a global concern; concentrations reach 580,000 pieces per km(2) and production is increasing exponentially. Although a large number of empirical studies provide emerging evidence of impacts to wildlife, there has been little systematic assessment of risk. We performed a spatial risk analysis using predicted debris distributions and ranges for 186 seabird species to model debris exposure. We adjusted the model using published data on plastic ingestion by seabirds. Eighty of 135 (59%) species with studies reported in the literature between 1962 and 2012 had ingested plastic, and, within those studies, on average 29% of individuals had plastic in their gut. Standardizing the data for time and species, we estimate the ingestion rate would reach 90% of individuals if these studies were conducted today. Using these results from the literature, we tuned our risk model and were able to capture 71% of the variation in plastic ingestion based on a model including exposure, time, study method, and body size. We used this tuned model to predict risk across seabird species at the global scale. The highest area of expected impact occurs at the Southern Ocean boundary in the Tasman Sea between Australia and New Zealand, which contrasts with previous work identifying this area as having low anthropogenic pressures and concentrations of marine debris. We predict that plastics ingestion is increasing in seabirds, that it will reach 99% of all species by 2050, and that effective waste management can reduce this threat.

  7. Ship-based seabird and marine mammal survey pff Mauritania, 4 - 14 september 2015

    NARCIS (Netherlands)

    Camphuysen, C.J.; Spanje, van T.M.; Verdaat, J.P.

    2015-01-01

    This report presents the first results obtained during the ship-based seabird and marine mammal surveys conducted between 4 and 14 September 2015 and must be seen as a preliminary analysis of the data and a further step in data collection. This cruise was part of the longer-term research project fin

  8. The paradox of pelagic food webs in the northern Bering Sea—I. Seabird food habits

    Science.gov (United States)

    Springer, Alan M.; Murphy, Edward C.; Roseneau, David G.; McRoy, C. Peter; Cooper, Brian A.

    1987-08-01

    Two distinct environmental settings in the Bering Strait region of the northern Bering Sea lead to characteristic pathways of energy flow through primarily pelagic food webs to avian consumers. In Norton Sound, a large, shallow embayment on the northeastern coast, the physical environment is dominated by the discharge of the Yukon River and by a large seasonal temperature signal. Seabirds breeding at Bluff, the largest colony in Norton Sound, number in the order of 5 × 10 4 and require 1.2 × 10 6 g C d -1. Two piscivorous species constitute the bulk of all seabirds there and are supported by a pelagic food web typical of the coastal zone of the Bering and Chukchi seas. This food web also is present around St. Lawrence Island, on the northwestern shelf, and is important to at least one species of seabird there. In addition, and generally more important, St. Lawrence Island is in a biologically rich environment resulting from the northward flow of water that originates along the continental shelf break of the Bering Sea. This flow apparently accounts for the unexpected presence of oceanic zooplankton and a diversity of forage fishes on the shallow northern shelf that support an abundant and taxonomically rich avifauna. In comparison to Norton Sound, breeding seabirds on St. Lawrence Island number in the order of 2 × 10 6, with planktivores consuming about 8 × 10 6 g C d -1 and piscivores consuming about 16 × 10 6 g C d -1.

  9. Differential effects of a local industrial sand lance fishery on seabird breeding performance

    DEFF Research Database (Denmark)

    Frederiksen, M.; Jensen, Henrik; Daunt, F.;

    2008-01-01

    fluctuations. We evaluated the effects of an industrial sand lance (Ammodytes marinus) fishery off the North Sea coast of the United Kingdom, which has been opened and closed in a quasi-experimental fashion, on sand-lance-dependent breeding seabirds. Controlling for environmental variation ( sea surface...

  10. Stable isotope biogeochemistry of seabird guano fertilization: results from growth chamber studies with maize (Zea mays.

    Directory of Open Access Journals (Sweden)

    Paul Szpak

    Full Text Available BACKGROUND: Stable isotope analysis is being utilized with increasing regularity to examine a wide range of issues (diet, habitat use, migration in ecology, geology, archaeology, and related disciplines. A crucial component to these studies is a thorough understanding of the range and causes of baseline isotopic variation, which is relatively poorly understood for nitrogen (δ(15N. Animal excrement is known to impact plant δ(15N values, but the effects of seabird guano have not been systematically studied from an agricultural or horticultural standpoint. METHODOLOGY/PRINCIPAL FINDINGS: This paper presents isotopic (δ(13C and δ(15N and vital data for maize (Zea mays fertilized with Peruvian seabird guano under controlled conditions. The level of (15N enrichment in fertilized plants is very large, with δ(15N values ranging between 25.5 and 44.7‰ depending on the tissue and amount of fertilizer applied; comparatively, control plant δ(15N values ranged between -0.3 and 5.7‰. Intraplant and temporal variability in δ(15N values were large, particularly for the guano-fertilized plants, which can be attributed to changes in the availability of guano-derived N over time, and the reliance of stored vs. absorbed N. Plant δ(13C values were not significantly impacted by guano fertilization. High concentrations of seabird guano inhibited maize germination and maize growth. Moreover, high levels of seabird guano greatly impacted the N metabolism of the plants, resulting in significantly higher tissue N content, particularly in the stalk. CONCLUSIONS/SIGNIFICANCE: The results presented in this study demonstrate the very large impact of seabird guano on maize δ(15N values. The use of seabird guano as a fertilizer can thus be traced using stable isotope analysis in food chemistry applications (certification of organic inputs. Furthermore, the fertilization of maize with seabird guano creates an isotopic signature very similar to a high-trophic level

  11. Bird Avoidance Model

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is an unpublished report on the bird avoidance model to predict bird strike hazards with low flying aircraft. Included is peak periods for different species of...

  12. Avoiding Computer Viruses.

    Science.gov (United States)

    Rowe, Joyce; And Others

    1989-01-01

    The threat of computer sabotage is a real concern to business teachers and others responsible for academic computer facilities. Teachers can minimize the possibility. Eight suggestions for avoiding computer viruses are given. (JOW)

  13. Avoid Mosquito Bites

    Science.gov (United States)

    ... Submit What's this? Submit Button Past Emails Avoid Mosquito Bites Language: English (US) Español (Spanish) Recommend on ... finding a travel medicine clinic near you. Prevent Mosquito Bites While Traveling Mosquito bites are bothersome enough, ...

  14. Currents, temperature, and salinity data recorded continuously from May 12, 2010 to December 16, 2010 from the surface to 1000 meters at a coastal location near the 1600 meters isobath off SW Oahu, Hawaii (NODC Accession 0072305)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The dataset contains ADCP Workhorse Long Ranger current records from 50 to 950m depth and Seabird CTD at 20, 80, 130, 230, 500, 850, and 1000m, recorded continuously...

  15. Color-avoiding percolation

    CERN Document Server

    Krause, Sebastian M; Zlatić, Vinko

    2016-01-01

    Many real world networks have groups of similar nodes which are vulnerable to the same failure or adversary. Nodes can be colored in such a way that colors encode the shared vulnerabilities. Using multiple paths to avoid these vulnerabilities can greatly improve network robustness. Color-avoiding percolation provides a theoretical framework for analyzing this scenario, focusing on the maximal set of nodes which can be connected via multiple color-avoiding paths. In this paper we extend the basic theory of color-avoiding percolation that was published in [Krause et. al., Phys. Rev. X 6 (2016) 041022]. We explicitly account for the fact that the same particular link can be part of different paths avoiding different colors. This fact was previously accounted for with a heuristic approximation. We compare this approximation with a new, more exact theory and show that the new theory is substantially more accurate for many avoided colors. Further, we formulate our new theory with differentiated node functions, as s...

  16. Effectiveness of tori line use to reduce seabird bycatch in pelagic longline fishing

    Science.gov (United States)

    Domingo, Andrés; Abreu, Martin; Forselledo, Rodrigo; Yates, Oliver

    2017-01-01

    Industrial longline fisheries cause the death of large numbers of seabirds annually. Various mitigation measures have been proposed, including the use of tori lines. In this study the efficiency of a single tori line to reduce seabird bycatch was tested on pelagic longline vessels (25-37m length). Thirteen fishing trips were carried out in the area and season of the highest bycatch rates recorded in the southwest Atlantic (2009–2011). We deployed two treatments in random order: sets with a tori line and without a tori line (control treatment). The use of a tori line significantly reduced seabird bycatch rates. Forty three and seven birds were captured in the control (0.85 birds/1,000 hooks, n = 49 sets) and in the tori line treatment (0.13 birds/1,000 hooks, n = 51 sets), respectively. In 47% of the latter sets the tori line broke either because of entanglement with the longline gear or by tension. This diminished the tori line effectiveness; five of the seven captures during sets where a tori line was deployed were following ruptures. Nine additional trips were conducted with a tori line that was modified to reduce entanglements (2012–2016). Seven entanglements were recorded in 73 longline sets. The chance of a rupture on these trips was 4% (95% c.l. = 1–18%) of that during 2009–2011. This work shows that the use of a tori line reduces seabird bycatch in pelagic longline fisheries and is a practice suitable for medium size vessels (~25-40m length). Because the study area has historically very high bycatch rates at global level, this tori line design is potentially useful to reduce seabird bycatch in many medium size pelagic longline vessel fishing in the southern hemisphere. PMID:28886183

  17. Predicting cetacean and seabird habitats across a productivity gradient in the South Pacific gyre

    Science.gov (United States)

    Mannocci, Laura; Catalogna, Maxime; Dorémus, Ghislain; Laran, Sophie; Lehodey, Patrick; Massart, Wendy; Monestiez, Pascal; Van Canneyt, Olivier; Watremez, Pierre; Ridoux, Vincent

    2014-01-01

    Oligotrophic regions are expected to host low densities of top predators. Nevertheless, top predators with contrasting energetic costs might respond differently to the productivity of their habitats. Predators with high energetic demands might be constrained to select the most productive habitats to meet their high energetic requirements, whereas less active predators would be able to satisfy their needs by exploiting either high or low productivity habitats. Although situated in the core of the South Pacific oligotrophic gyre, French Polynesia is characterized by a fairly marked productivity gradient from the extremely oligotrophic Australs area to the more productive Marquesas area. The aim of this study was to investigate cetacean and seabird habitats in French Polynesia in light of their general energetic constraints. We collected cetacean and seabird sightings from an aerial survey across French Polynesian waters during the austral summer 2011. We classified cetaceans and seabirds into energetic guilds according to the literature. For each guild, we built generalized additive models along with static covariates and oceanographic covariates at the seasonal and climatological resolutions. We provided regional habitat predictions for Delphininae, Globicephalinae, sperm and beaked whales, tropicbirds, grey terns, noddies, white terns, boobies, petrels and shearwaters, sooty terns and frigatebirds. Explained deviances ranged from 5% to 30% for cetaceans and from 14% to 29% for seabirds. Cetaceans clearly responded to the productivity gradient, with the highest predicted densities around the productive waters of the Marquesas. However, Delphininae and Globicephalinae, characterized by higher energetic demands, depended more strongly on productivity, showing a ratio of 1-26 and 1-31 between their lowest and highest density areas respectively, compared to the less active sperm and beaked whales (showing only a ratio of 1-3.5 in predicted densities). In contrast

  18. Invasive rats alter woody seedling composition on seabird-dominated islands in New Zealand.

    Science.gov (United States)

    Grant-Hoffman, Madeline N; Mulder, Christa P; Bellingham, Peter J

    2010-06-01

    Invasive rats (Rattus rattus, R. norvegicus, R. exulans) have large impacts on island habitats through both direct and indirect effects on plants. Rats affect vegetation by extirpating burrowing seabirds through consumption of eggs, chicks, and adults. These seabirds serve as ecosystem engineers, affecting plant communities by burying and trampling seeds and seedlings, and by altering microclimate. Rats also directly affect plant communities by consuming seeds and seedlings. We studied the direct and indirect impacts of rats on the seedlings of woody plants on 21 islands in northern New Zealand. We compared seedling densities and richness on islands which differed in status with respect to rats: nine islands where rats never invaded, seven islands where rats were present at the time of our study, and five islands where rats were either eradicated or where populations were likely to be small as a result of repeated eradications and re-invasions. In addition, we compared plots from a subset of the 21 islands with different burrow densities to examine the effects of burrowing seabirds on plants while controlling for other factors that differ between islands. We categorized plant communities by species composition and seedling density in a cluster analysis. We found that burrow densities explained more variation in seedling communities than rat status. In areas with high seabird burrow density seedling densities were low, especially for the smallest seedlings. Species richness and diversity of seedlings, but not seedling density, were most influenced by changes in microclimate induced by seabirds. Islands where rats had been eradicated or that had low rat populations had the lowest diversity and richness of seedlings (and adults), but the highest seedling density. Seedling communities on these islands were dominated by Pseudopanax lessonii and Coprosma macrocarpa. This indicates lasting effects of rats that may prevent islands from returning to pre-invasion states.

  19. Diversity and global distribution of the Coxiella intracellular bacterium in seabird ticks.

    Science.gov (United States)

    Duron, Olivier; Jourdain, Elsa; McCoy, Karen D

    2014-09-01

    The obligate intracellular bacterium Coxiella burnetii is the etiological agent of Q fever, a widespread zoonotic disease whose most common animal reservoirs are domestic ruminants. Recently, a variety of Coxiella-like organisms have also been reported from non-mammalian hosts, including pathogenic forms in birds and forms without known effects in ticks, raising questions about the potential importance of non-mammalian hosts as reservoirs of Coxiella in the wild. In the present study, we examined the potential role of globally-distributed seabird ticks as reservoirs of these bacteria. To this aim, we tested for Coxiella infection 11 geographically distinct populations of two tick species frequently found in seabird breeding colonies, the hard tick Ixodes uriae (Ixodidae) and soft ticks of the Ornithodoros (Carios) capensis group (Argasidae). We found Coxiella-like organisms in all O. capensis sensu lato specimens, but only in a few I. uriae specimens of one population. The sequencing of 16S rDNA and GroEL gene sequences further revealed an unexpected Coxiella diversity, with seven genetically distinct Coxiella-like organisms present in seabird tick populations. Phylogenetic analyses show that these Coxiella-like organisms originate from three divergent subclades within the Coxiella genus and that none of the Coxiella strains found in seabird ticks are genetically identical to the forms known to be associated with pathogenicity in vertebrates, including C. burnetii. Using this data set, we discuss the potential epidemiological significance of the presence of Coxiella in seabird ticks. Notably, we suggest that these organisms may not be pathogenic forms, but rather behave as endosymbionts engaged in intricate interactions with their tick hosts.

  20. Demonstration projects : learning by experience : the Seabird Island demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2009-10-15

    This article described the Seabird Island sustainable community housing demonstration project near Agassiz, British Columbia. The project provides a sustainable, affordable place for 7 families and demonstrates a new way to build and design communities using renewable energy technologies to provide residents with better quality, energy efficient housing while reducing costs and minimizing environmental impacts. The design integrates renewable energy sources such as wind, solar and geothermal energy to save on heating and lighting costs. This article noted some of the dubious design features that could have been screened out at the design stage if careful analysis had been carried out. It described features such as the solar orientation; climatic factors that influenced the form and details of the building; the high-efficiency, condensing, natural gas water heater for space heating combined with a forced-air and radiant-floor heating system; solariums that provided solar preheating of domestic hot water; ventilation air preheating; the solar roof; an earth-tube ventilation system; and 3 wind turbines to generate electricity to offset conventional electricity sources. Canada Mortgage and Housing Corporation has monitored several of the systems in order to evaluate the extent to which these features have influenced the performance of the dwelling units. The energy use in all 7 units was documented along with indoor air quality. An energy performance rating of EnerGuide 80 was achieved, which is comparable to R-2000. The monitoring study revealed that wind energy at this location was not sufficient to justify the installation of the wind turbines. The solar steel roof/solarium energy system did not perform as expected. In addition, the earth-tube ventilation system provided little heat and its overall contribution to ventilation was uncertain. Other deficiencies were also noted, such as leaky ductwork, non-operational dampers and poorly integrated control systems. The

  1. Breeding distribution and abundance of seabirds on islands off north-central Chile Distribución reproductiva y abundancia de aves marinas en islas del norte y centro de Chile

    Directory of Open Access Journals (Sweden)

    ALEJANDRO SIMEONE

    2003-06-01

    Full Text Available Between 1999 and 2003 we collected information on the breeding distribution and abundance of 12 seabird species occurring on nine islands off the coasts of north and central Chile (27°-33°S. The Peruvian booby Sula variegata was the most abundant seabird with a breeding population of ca. 18,000 pairs concentrated in two islands, followed by the Humboldt penguin Spheniscus humboldti with ca. 9,000 pairs, the largest colony being at Chañaral Island with ca. 7,000 pairs. Kelp gulls Larus dominicanus bred at all the surveyed sites in colonies of variable size, ranging from 40 to 2,000 pairs. Peruvian diving-petrels Pelecanoides garnotii and Peruvian pelicans Pelecanus occidentalis bred at restricted sites, but generally in large colonies. Magellanic penguins Spheniscus magellanicus, wedge-rumped storm-petrels Oceanodroma tethys, Neotropical cormorants Hypoleucos brasiliensis, guanay cormorants Leucocarbo bougainvillii, red-legged cormorants Stictocarbo gairmardi, band-tailed gulls Larus belcheri and Inca terns Larosterna inca nested at few sites forming small colonies (from a few to 150 pairs. Two new breeding sites are reported for the Peruvian diving-petrel and nesting of the wedge-rumped storm-petrel is confirmed on the Chilean coast for the first time. Despite protective status, most of the islands showed human disturbance, derived mainly from guano harvesting, egging and tourism. On at least five of these islands we were able to confirm introduced mammals including rats, rabbits and cats. These factors are likely to be detrimental to seabirds and thus demand detailed assessment. Further comprehensive ornithological surveys in other areas are needed so as to improve the scarce knowledge that we currently have on the seabird populations along the Chilean coast

  2. Pelagic and near-shore seabird densities in the western Aleutian Islands as determined by transect counts in 1975 and 1976, also partial data on seabird densities in the eastern Aleutians and mammal observations from Unimak to Attu, 1976

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report presents the results of a ship-board seabird census project in the Western Aleutian Islands (Gareloi to Attu). Three variations of the transect count...

  3. A multi-scale problem arising in a model of avian flu virus in a seabird colony

    Energy Technology Data Exchange (ETDEWEB)

    Clancy, C F; O' Callaghan, M J A; Kelly, T C [Department of Zoology, Ecology and Plant Science, Distillery Fields, North Mall, University College Cork (Ireland)

    2006-12-01

    Understanding the dynamics of epidemics of novel pathogens such as the H5N1 strain of avian influenza is of crucial importance to public and veterinary health as well as wildlife ecology. We model the effect of a new virus on a seabird colony, where no pre-existing Herd Immunity exists. The seabirds in question are so-called K-strategists, i.e. they have a relatively long life expectancy and very low reproductive output. They live in isolated colonies which typically contain tens of thousands of birds. These densely populated colonies, with so many birds competing for nesting space, would seem to provide perfect conditions for the entry and spread of an infection. Yet there are relatively few reported cases of epidemics among these seabirds. We develop a SEIR model which incorporates some of the unusual features of seabird population biology and examine the effects of introducing a pathogen into the colony.

  4. The status of ledge-nesting seabirds at monitoring sites in the Aleutian Islands, Alaska in summer 1989

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Seabird monitoring in the Aleutian Islands durin9 summer 1989 focused on a guild of ledge-nesting species including northern fulmar (Fulmarus glacialis), cormorants...

  5. Seabird investigations on Middleton Island during the summer 1976 with notes on the other island avifauna : Draft report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The results of seabird investigations on Middleton Island, Alaska, during the summer of 1976 are reported here. The purpose of this study was to gather baseline...

  6. NOAA ESRI Grid - predictions of seabird diversity in the New York offshore planning area made by the NOAA Biogeography Branch

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents seabird diversity predictions from spatial models developed for the New York offshore spatial planning area. This raster was derived from...

  7. Changes in colony size and reproductive success of seabirds at the Semidi Islands, Alaska, 1977-1990

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Monitoring of seabirds at Chowiet Island during the 1990 breeding season to determine if populations and productivity of northern fulmars, black-legged kittiwakes,...

  8. The status of ledge-nesting seabirds in the Pribilof Islands, Alaska, 1976-1986: An executive summary

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is a brief summary of our findings in 1966 on six species of seabirds (northern fulmar, red-faced cormorant, black- and red-legged kittiwakes, and common...

  9. Burrowing seabird effects on invertebrate communities in soil and litter are dominated by ecosystem engineering rather than nutrient addition.

    Science.gov (United States)

    Orwin, Kate H; Wardle, David A; Towns, David R; St John, Mark G; Bellingham, Peter J; Jones, Chris; Fitzgerald, Brian M; Parrish, Richard G; Lyver, Phil O'B

    2016-01-01

    Vertebrate consumers can be important drivers of the structure and functioning of ecosystems, including the soil and litter invertebrate communities that drive many ecosystem processes. Burrowing seabirds, as prevalent vertebrate consumers, have the potential to impact consumptive effects via adding marine nutrients to soil (i.e. resource subsidies) and non-consumptive effects via soil disturbance associated with excavating burrows (i.e. ecosystem engineering). However, the exact mechanisms by which they influence invertebrates are poorly understood. We examined how soil chemistry and plant and invertebrate communities changed across a gradient of seabird burrow density on two islands in northern New Zealand. Increasing seabird burrow density was associated with increased soil nutrient availability and changes in plant community structure and the abundance of nearly all the measured invertebrate groups. Increasing seabird densities had a negative effect on invertebrates that were strongly influenced by soil-surface litter, a positive effect on fungal-feeding invertebrates, and variable effects on invertebrate groups with diverse feeding strategies. Gastropoda and Araneae species richness and composition were also influenced by seabird activity. Generalized multilevel path analysis revealed that invertebrate responses were strongly driven by seabird engineering effects, via increased soil disturbance, reduced soil-surface litter, and changes in trophic interactions. Almost no significant effects of resource subsidies were detected. Our results show that seabirds, and in particular their non-consumptive effects, were significant drivers of invertebrate food web structure. Reductions in seabird populations, due to predation and human activity, may therefore have far-reaching consequences for the functioning of these ecosystems.

  10. Using large scale surveys to investigate seasonal variations in seabird distribution and abundance. Part I: The North Western Mediterranean Sea

    Science.gov (United States)

    Pettex, Emeline; David, Léa; Authier, Matthieu; Blanck, Aurélie; Dorémus, Ghislain; Falchetto, Hélène; Laran, Sophie; Monestiez, Pascal; Van Canneyt, Olivier; Virgili, Auriane; Ridoux, Vincent

    2017-07-01

    Scientific investigation in offshore areas are logistically challenging and expensive, therefore the available knowledge on seabird at sea distribution and abundance, as well as their seasonal variations, remains limited. To investigate the seasonal variability in seabird distribution and abundance in the North-Western Mediterranean Sea (NWMS), we conducted two large-scale aerial surveys in winter 2011-12 and summer 2012, covering a 181,400 km2 area. Following a strip-transect method, observers recorded a total of 4141 seabird sightings in winter and 2334 in summer, along 32,213 km. Using geostatistical methods, we generated sightings density maps for both seasons, as well as estimates of density and abundance. Most taxa showed seasonal variations in their density and distribution patterns, as they used the area either for wintering or for breeding. Highest densities of seabirds were recorded during winter, although large-sized shearwaters, storm petrels and terns were more abundant during summer. Consequently, with nearly 170,000 seabirds estimated in winter, the total abundance was twice higher in winter. Coastal waters of the continental shelf were generally more exploited by seabirds, even though some species, such as Mediterranean gulls, black-headed gulls, little gulls and storm petrels were found at high densities in highly offshore waters. Our results revealed areas highly exploited by the seabird community in the NWMS, such as the Gulf of Lion, the Tuscan region, and the area between Corsica and Sardinia. In addition, these large-scale surveys provide a baseline for the monitoring of seabird at sea distribution, and could inform the EU Marine Strategy Framework Directive.

  11. Impact of climate change on zooplankton communities, seabird populations and arctic terrestrial ecosystem—A scenario

    Science.gov (United States)

    Stempniewicz, Lech; Błachowiak-Samołyk, Katarzyna; Węsławski, Jan M.

    2007-11-01

    Many arctic terrestrial ecosystems suffer from a permanent deficiency of nutrients. Marine birds that forage at sea and breed on land can transport organic matter from the sea to land, and thus help to initiate and sustain terrestrial ecosystems. This organic matter initiates the emergence of local tundra communities, increasing primary and secondary production and species diversity. Climate change will influence ocean circulation and the hydrologic regime, which will consequently lead to a restructuring of zooplankton communities between cold arctic waters, with a dominance of large zooplankton species, and Atlantic waters in which small species predominate. The dominance of large zooplankton favours plankton-eating seabirds, such as the little auk ( Alle alle), while the presence of small zooplankton redirects the food chain to plankton-eating fish, up through to fish-eating birds (e.g., guillemots Uria sp.). Thus, in regions where the two water masses compete for dominance, such as in the Barents Sea, plankton-eating birds should dominate the avifauna in cold periods and recess in warmer periods, when fish-eaters should prevail. Therefore under future anthropogenic climate scenarios, there could be serious consequences for the structure and functioning of the terrestrial part of arctic ecosystems, due in part to changes in the arctic marine avifauna. Large colonies of plankton-eating little auks are located on mild mountain slopes, usually a few kilometres from the shore, whereas colonies of fish-eating guillemots are situated on rocky cliffs at the coast. The impact of guillemots on the terrestrial ecosystems is therefore much smaller than for little auks because of the rapid washing-out to sea of the guano deposited on the seabird cliffs. These characteristics of seabird nesting sites dramatically limit the range of occurrence of ornithogenic soils, and the accompanying flora and fauna, to locations where talus-breeding species occur. As a result of climate

  12. Will the Effects of Sea-Level Rise Create Ecological Traps for Pacific Island Seabirds?

    Directory of Open Access Journals (Sweden)

    Michelle H Reynolds

    Full Text Available More than 18 million seabirds nest on 58 Pacific islands protected within vast U.S. Marine National Monuments (1.9 million km2. However, most of these seabird colonies are on low-elevation islands and sea-level rise (SLR and accompanying high-water perturbations are predicted to escalate with climate change. To understand how SLR may impact protected islands and insular biodiversity, we modeled inundation and wave-driven flooding of a globally important seabird rookery in the subtropical Pacific. We acquired new high-resolution Digital Elevation Models (DEMs and used the Delft3D wave model and ArcGIS to model wave heights and inundation for a range of SLR scenarios (+0.5, +1.0, +1.5, and +2.0 m at Midway Atoll. Next, we classified vegetation to delineate habitat exposure to inundation and identified how breeding phenology, colony synchrony, and life history traits affect species-specific sensitivity. We identified 3 of 13 species as highly vulnerable to SLR in the Hawaiian Islands and quantified their atoll-wide distribution (Laysan albatross, Phoebastria immutabilis; black-footed albatross, P. nigripes; and Bonin petrel, Pterodroma hypoleuca. Our models of wave-driven flooding forecast nest losses up to 10% greater than passive inundation models at +1.0 m SLR. At projections of + 2.0 m SLR, approximately 60% of albatross and 44% of Bonin petrel nests were overwashed displacing more than 616,400 breeding albatrosses and petrels. Habitat loss due to passive SLR may decrease the carrying capacity of some islands to support seabird colonies, while sudden high-water events directly reduce survival and reproduction. This is the first study to simulate wave-driven flooding and the combined impacts of SLR, groundwater rise, and storm waves on seabird colonies. Our results highlight the need for early climate change planning and restoration of higher elevation seabird refugia to prevent low-lying protected islands from becoming ecological traps in the

  13. Helping Students Avoid Plagiarism.

    Science.gov (United States)

    Wilhoit, Stephen

    1994-01-01

    Discusses how and why college students commit plagiarism, suggesting techniques that instructors can use to help student avoid plagiarism. Instructors should define and discuss plagiarism thoroughly; discuss hypothetical cases; review the conventions of quoting and documenting material; require multiple drafts of essays; and offer responses…

  14. On partitions avoiding right crossings

    CERN Document Server

    Yan, Sherry H F

    2011-01-01

    Recently, Chen et al. derived the generating function for partitions avoiding right nestings and posed the problem of finding the generating function for partitions avoiding right crossings. In this paper, we derive the generating function for partitions avoiding right crossings via an intermediate structure of partial matchings avoiding 2-right crossings and right nestings. We show that there is a bijection between partial matchings avoiding 2-right crossing and right nestings and partitions avoiding right crossings.

  15. Plastic debris in great skua (Stercorarius skua) pellets corresponds to seabird prey species.

    Science.gov (United States)

    Hammer, S; Nager, R G; Johnson, P C D; Furness, R W; Provencher, J F

    2016-02-15

    Plastic is a common item in marine environments. Studies assessing seabird ingestion of plastics have focused on species that ingest plastics mistaken for prey items. Few studies have examined a scavenger and predatory species that are likely to ingest plastics indirectly through their prey items, such as the great skua (Stercorarius skua). We examined 1034 regurgitated pellets from a great skua colony in the Faroe Islands for plastics and found approximately 6% contained plastics. Pellets containing remains of Northern fulmars (Fulmarus glacialis) had the highest prevalence of plastic. Our findings support previous work showing that Northern fulmars have higher loads of plastics than other sympatric species. This study demonstrates that marine plastic debris is transferred from surface feeding seabird species to predatory great skuas. Examination of plastic ingestion in species that do not ingest plastics directly can provide insights into how plastic particles transfer vertically within the food web.

  16. Winter temperature affects the prevalence of ticks in an Arctic seabird.

    Directory of Open Access Journals (Sweden)

    Sébastien Descamps

    Full Text Available The Arctic is rapidly warming and host-parasite relationships may be modified by such environmental changes. Here, I showed that the average winter temperature in Svalbard, Arctic Norway, explained almost 90% of the average prevalence of ticks in an Arctic seabird, the Brünnich's guillemot Uria lomvia. An increase of 1°C in the average winter temperature at the nesting colony site was associated with a 5% increase in the number of birds infected by these ectoparasites in the subsequent breeding season. Guillemots were generally infested by only a few ticks (≤5 and I found no direct effect of tick presence on their body condition and breeding success. However, the strong effect of average winter temperature described here clearly indicates that tick-seabird relationships in the Arctic may be strongly affected by ongoing climate warming.

  17. Phytoplankton community structure is influenced by seabird guano enrichment in the Southern Ocean

    Science.gov (United States)

    Shatova, O. A.; Wing, S. R.; Hoffmann, L. J.; Wing, L. C.; Gault-Ringold, M.

    2017-05-01

    Phytoplankton biomass, productivity and community structure are strongly influenced by differences in nutrient concentrations among oceanographic water masses. Changes in community composition, particularly in the distribution of cell sizes, can result in dramatic changes in the energetics of pelagic food webs and ecosystem function in terms of biogeochemical cycling and carbon sequestration. Here we examine responses of natural phytoplankton communities from four major water masses in the Southern Ocean to enrichment from seabird guano, a concentrated source of bioactive metals (Mn, Fe, Co, Ni, Cu, Zn) and macronutrients (N, P), in a series of incubation experiments. Phytoplankton communities from sub-tropical water, modified sub-tropical water from the Snares Island wake, sub-Antarctic water and Antarctic water from the Ross Sea, each showed dramatic changes in community structure following additions of seabird guano. We observed particularly high growth of prymnesiophytes in response to the guano-derived nutrients within sub-Antarctic and sub-tropical frontal zones, resulting in communities dominated by larger cell sizes than in control incubations. Community changes within treatments enriched with guano were distinct, and in most cases more extensive, than those observed for treatments with additions of macronutrients (N, P) or iron (Fe) alone. These results provide the first empirical evidence that seabird guano enrichment can drive significant changes in the structure and composition of natural phytoplankton communities. Our findings have important implications for understanding the consequences of accumulation of bioactive metals and macronutrients within food webs and the role of seabirds as nutrient vectors within the Southern Ocean ecosystem.

  18. Estimating population size of a nocturnal burrow-nesting seabird using acoustic monitoring and habitat mapping

    Directory of Open Access Journals (Sweden)

    Steffen Oppel

    2014-04-01

    Full Text Available Population size assessments for nocturnal burrow-nesting seabirds are logistically challenging because these species are active in colonies only during darkness and often nest on remote islands where manual inspections of breeding burrows are not feasible. Many seabird species are highly vocal, and recent technological innovations now make it possible to record and quantify vocal activity in seabird colonies. Here we test the hypothesis that remotely recorded vocal activity in Cory’s shearwater (Calonectris borealis breeding colonies in the North Atlantic increases with nest density, and combined this relationship with cliff habitat mapping to estimate the population size of Cory’s shearwaters on the island of Corvo (Azores. We deployed acoustic recording devices in 9 Cory’s shearwater colonies of known size to establish a relationship between vocal activity and local nest density (slope = 1.07, R2 = 0.86, p < 0.001. We used this relationship to predict the nest density in various cliff habitat types and produced a habitat map of breeding cliffs to extrapolate nest density around the island of Corvo. The mean predicted nest density on Corvo ranged from 6.6 (2.1–16.2 to 27.8 (19.5–36.4 nests/ha. Extrapolation of habitat-specific nest densities across the cliff area of Corvo resulted in an estimate of 6326 Cory’s shearwater nests (95% confidence interval: 3735–10,524. This population size estimate is similar to previous assessments, but is too imprecise to detect moderate changes in population size over time. While estimating absolute population size from acoustic recordings may not be sufficiently precise, the strong positive relationship that we found between local nest density and recorded calling rate indicates that passive acoustic monitoring may be useful to document relative changes in seabird populations over time.

  19. Seabirds of Easter Island, Salas y Gómez Island and Desventuradas Islands, southeastern Pacific Ocean

    OpenAIRE

    Flores,Marcelo A; Roberto P Schlatter; Rodrigo Hucke-Gaete

    2014-01-01

    We reviewed available information on seabirds inhabiting Easter Island, Salas y Gómez Island and Desventuradas Islands and their adjacent waters through an analysis of published and grey literature. Results obtained indicate that a total of 37 species are present in the study area and that, among the orders represented, the Procellariiformes and Charadriiformes are the dominant taxa (29 species). Moreover, the family Procellariidae is represented by 13 species and Laridae by 7 species. There ...

  20. Detecting and measuring senescence in wild birds: experience with long-lived seabirds.

    Science.gov (United States)

    Nisbet, I C

    2001-04-01

    This paper points out and discusses several practical and methodological problems that arise in attempts to detect and measure senescent declines in survival or breeding performance of wild animals, with specific emphasis on long-lived seabirds. Birds have no anatomical markers of age, so studies of age-related biology require marking individuals at the time of hatching and following them throughout their lives. Seabirds live longer than the working lifespan of biologists, and longer than the turnover times of study techniques or theories of senescence. Seabirds are exposed to changing environmental and demographic conditions and cannot be assumed to be in demographic equilibrium. Sample sizes of the oldest age-classes are always small, requiring either marking very large numbers of birds at hatching or continuing studies of old birds over many years. Incomplete sampling requires the use of mark-recapture models that have only been developed in the last 20years. Mortality selection resulting from demographic heterogeneity (selective survival of high-quality individuals) can offset or confound the effects of senescent changes within individuals. Many of these problems are amenable to solution and will be probably solved within a few years. In the meantime, this paper recommends that reviewers should be cautious about accepting published reports of senescent declines in natural populations.

  1. INTRAVENOUS REGIONAL ANTIBIOTIC PERFUSION THERAPY AS AN ADJUNCTIVE TREATMENT FOR DIGITAL LESIONS IN SEABIRDS.

    Science.gov (United States)

    Fiorello, Christine V

    2017-03-01

    Foot infections are a common problem among seabirds in wildlife rehabilitation. Pododermatitis and digital infections are often challenging to treat because of the presence of suboptimal substrates, abnormal weight-bearing due to injuries, and suboptimal nutritional or health status. Seabirds represent the majority of animals requiring rehabilitation after oil spills, and foot problems are a common reason for euthanasia among these birds. Antibiotic intravenous regional perfusion therapy is frequently used in humans and other species to treat infections of the distal extremities, but it has not been evaluated in seabirds. During the 2015 Refugio oil spill response, four birds with foot lesions (pododermatitis, osteomyelitis, or both) were treated with ampicillin/sulbactam administered intravenously to the affected limb(s) in addition to systemic antibiotics and anti-inflammatories. Three of the birds, all brown pelicans ( Pelecanus occidentalis ) recovered rapidly and were released. Two of these birds had acute pododermatitis and were treated once with intravenous regional perfusion. They were released approximately 3 wk after the perfusion therapy. The third pelican had osteomyelitis of a digit. It was treated twice with intravenous regional perfusion and was released about 1 mo after the initial perfusion therapy. The fourth bird, a Pacific loon ( Gavia pacifica ), was treated once with perfusion therapy but did not respond to treatment and was euthanatized. No serious adverse effects were observed. This technique should be explored further in avian species.

  2. Remotely sensed wind speed predicts soaring behaviour in a wide-ranging pelagic seabird.

    Science.gov (United States)

    Gibb, Rory; Shoji, Akiko; Fayet, Annette L; Perrins, Chris M; Guilford, Tim; Freeman, Robin

    2017-07-01

    Global wind patterns affect flight strategies in many birds, including pelagic seabirds, many of which use wind-powered soaring to reduce energy costs during at-sea foraging trips and migration. Such long-distance movement patterns are underpinned by local interactions between wind conditions and flight behaviour, but these fine-scale relationships are far less well understood. Here we show that remotely sensed ocean wind speed and direction are highly significant predictors of soaring behaviour in a migratory pelagic seabird, the Manx shearwater (Puffinus puffinus). We used high-frequency GPS tracking data (10 Hz) and statistical behaviour state classification to identify two energetic modes in at-sea flight, corresponding to flap-like and soar-like flight. We show that soaring is significantly more likely to occur in tailwinds and crosswinds above a wind speed threshold of around 8 m s(-1), suggesting that these conditions enable birds to reduce metabolic costs by preferentially soaring over flapping. Our results suggest a behavioural mechanism by which wind conditions may shape foraging and migration ecology in pelagic seabirds, and thus indicate that shifts in wind patterns driven by climate change could impact this and other species. They also emphasize the emerging potential of high-frequency GPS biologgers to provide detailed quantitative insights into fine-scale flight behaviour in free-living animals. © 2017 The Author(s).

  3. Evaluation of seabirds in Newfoundland and Labrador, Canada, as hosts of influenza A viruses.

    Science.gov (United States)

    Wille, Michelle; Huang, Yanyan; Robertson, Gregory J; Ryan, Pierre; Wilhelm, Sabina I; Fifield, David; Bond, Alexander L; Granter, Alissa; Munro, Hannah; Buxton, Rachel; Jones, Ian L; Fitzsimmons, Michelle G; Burke, Chantelle; Tranquilla, Laura McFarlane; Rector, Megan; Takahashi, Linda; Kouwenberg, Amy-Lee; Storey, Anne; Walsh, Carolyn; Hedd, April; Montevecchi, William A; Runstadler, Jonathan A; Ojkic, Davor; Whitney, Hugh; Lang, Andrew S

    2014-01-01

    Influenza A viruses infect a wide range of hosts, including many species of birds. Avian influenza A virus (AIV) infection appears to be most common in Anseriformes (ducks, geese, and swans) and some Charadriiformes (shorebirds and gulls), but many other birds also serve as hosts of AIV. Here, we evaluated the role of seabirds as hosts for AIV. We tested 3,160 swab samples from 13 seabird species between May 2008 and December 2011 in Newfoundland and Labrador, Canada. We also tested 156 serum samples for evidence of previous infection of AIV in Common Murres (Uria aalge) and Atlantic Puffins (Fratercula arctica). Avian influenza A virus was detected in breeding Common Murres and nonbreeding Thick-billed Murres (Uria lomvia), and Common Murres also had high antibody prevalence (44%). From these findings, combined with other studies showing AIV infection in murres, we conclude that murres are important for the ecology of AIV. For other species (Razorbill, Alca torda; Leach's Storm-Petrel, Oceanodroma leucorhoa; Black-legged Kittiwake, Rissa tridactyla; Atlantic Puffin) with good coverage (>100 samples) we did not detect AIV. However, serology indicates infection does occur in Atlantic Puffins, with 22% antibody prevalence found. The possibility of virus spread through dense breeding colonies and the long distance movements of these hosts make a more thorough evaluation of the role for seabirds as hosts of AIV important.

  4. Abundance and breeding distribution of seabirds in the northern part of the Danco Coast, Antarctic Peninsula

    Directory of Open Access Journals (Sweden)

    Mariana A. Juáres

    2013-02-01

    Full Text Available Seabird abundances and breeding distribution have the potential to serve as ecological indicators. The western Antarctic Peninsula is one of the three sites in the world with the greatest increases in local temperature during the last 50 years. The aim of this study was to monitor the distribution and abundance of breeding populations of seabirds in the northern sector of the Danco Coast, north-west of the Antarctic Peninsula, during the breeding season 2010/11. The birds were the Wilson′s storm petrel (Oceanites oceanicus, South Polar skua (Stercorarius maccormicki, kelp gull (Larus dominicanus, Antarctic tern (Sterna vittata, snowy sheathbill (Chionis alba, chinstrap penguin (Pygoscelis antarctica, southern giant petrel (Macronectes giganteus, gentoo penguin (Pygoscelis papua, Cape petrel (Daption capense and Antarctic shag (Phalacrocorax bransfieldensis. Annual breeding population growth increased in pygoscelids, southern giant petrel and sheathbill, and for the remaining species, breeding population trends were stable. Given that seabird populations can provide valuable information on the conditions of their feeding and nesting environments, this study highlights the need to maintain basics monitoring studies.

  5. The jellyfish buffet: jellyfish enhance seabird foraging opportunities by concentrating prey.

    Science.gov (United States)

    Sato, Nobuhiko N; Kokubun, Nobuo; Yamamoto, Takashi; Watanuki, Yutaka; Kitaysky, Alexander S; Takahashi, Akinori

    2015-08-01

    High levels of jellyfish biomass have been reported in marine ecosystems around the world, but understanding of their ecological role remains in its infancy. Jellyfish are generally thought to have indirect negative impacts on higher trophic-level predators, through changes in lower trophic pathways. However, high densities of jellyfish in the water column may affect the foraging behaviour of marine predators more directly, and the effects may not always be negative. Here, we present novel observations of a diving seabird, the thick-billed murre, feeding on fish aggregating among the long tentacles of large jellyfish, by using small video loggers attached to the birds. We show that the birds encountered large jellyfish, Chrysaora melanaster, during most of their dives, commonly fed on fish associated with jellyfish, and appeared to specifically target jellyfish with a high number of fish aggregating in their tentacles, suggesting the use of jellyfish may provide significant energetic benefits to foraging murres. We conclude that jellyfish provide feeding opportunities for diving seabirds by concentrating forage fish, and that the impacts of jellyfish on marine ecosystems are more complex than previously anticipated and may be beneficial to seabirds.

  6. Evaluation of noninvasive approach for monitoring PCB pollution of seabirds using preen gland oil.

    Science.gov (United States)

    Yamashita, Rei; Takada, Hideshige; Murakami, Michio; Fukuwaka, Masa-Aki; Watanuki, Yutaka

    2007-07-15

    Oil secreted from the preen gland (located at the base of the tail feathers) of seabirds can be collected from live birds. We determined PCB concentrations and profiles in the preen gland oil and corresponding abdominal adipose tissue collected from 30 seabirds (2 orders, 3 families, 10 genera, 13 species) to examine the utility of the oil as a monitoring medium. Samples were collected from seabirds that had died in traffic accidents or had become caught unintentionally in experimental drift nets and long-lines in the North Pacific Ocean. Significant concentrations of PCBs were detected in all oil samples, with a concentration range of 9-4834 ng/g-lipid and a geometric mean of 404 ng/ g-lipid. PCBs in the oil had more lower-chlorinated congeners than those in corresponding abdominal adipose, suggesting that they had less opportunity to undergo metabolism before they were secreted from the gland. We observed a weak but significant correlation between the PCB concentrations in the oil and abdominal adipose tissue (R2 = 0.19, P < 0.05). Correcting for the metabolic loss of PCBs on the basis of congener profiles improved the correlation (R2 = 0.48, P < 0.001), implying that congener-specific determination of PCBs in the preen gland oil enables us to estimate PCB concentrations in the abdominal adipose within 1 order of magnitude difference. The differences in PCB concentrations among the 13 species are discussed in terms of dietary behavior, habitat, and migration.

  7. Large-scale population assessment informs conservation management for seabirds in Antarctica and the Southern Ocean: A case study of Adélie penguins

    Directory of Open Access Journals (Sweden)

    Colin Southwell

    2017-01-01

    Full Text Available Antarctica and the Southern Ocean are increasingly affected by fisheries, climate change and human presence. Antarctic seabirds are vulnerable to all these threats because they depend on terrestrial and marine environments to breed and forage. We assess the current distribution and total abundance of Adélie penguins in East Antarctica and find there are 3.5 (95% CI 2.9–4.2 million individuals of breeding age along the East Antarctic coastline and 5.9 (4.2–7.7 million individuals foraging in the adjacent ocean after the breeding season. One third of the breeding population numbering over 1 million individuals breed within 10 km of research stations, highlighting the potential for human activities to impact Adélie penguin populations despite their current high abundance. The 16 Antarctic Specially Protected Areas currently designated in East Antarctica offer protection to breeding populations close to stations in four of six regional populations. The East Antarctic breeding population consumes an average of 193 500 tonnes of krill and 18 800 tonnes of fish during a breeding season, with consumption peaking at the end of the breeding season. These findings can inform future conservation management decisions in the terrestrial environment under the Protocol on Environmental Protection to develop a systematic network of protected areas, and in the marine environment under the Convention for the Conservation of Antarctic Marine Living Resources to allow the consumption needs of Adélie penguins to be taken into account when setting fishery catch limits. Extending this work to other penguin, flying seabird, seal and whale species is a priority for conservation management in Antarctica and the Southern Ocean.

  8. Social anxiety predicts avoidance behaviour in virtual encounters

    NARCIS (Netherlands)

    Rinck, M.; Rörtgen, T.; Lange, W.G.; Dotsch, R.; Wigboldus, D.H.J.; Becker, E.S.

    2010-01-01

    Avoidant behaviour is critical in social anxiety and social phobia, being a major factor in the maintenance of anxiety. However, almost all previous studies of social avoidance were restricted to using self-reports for the study of intentional aspects of avoidance. In contrast, the current study use

  9. Predicting attention and avoidance: when do avoiders attend?

    Science.gov (United States)

    Klein, Rupert; Knäuper, Bärbel

    2009-09-01

    Three avoidance measures, the Miller Behavioural Style Scale (MBSS), Index of Self-Regulation of Emotion (ISE) and Mainz Coping Inventory (MCI), were compared in their ability to predict attention and avoidance of threats in the emotional Stroop task. It was also examined if the avoidance mechanism of individuals who would normally avoid threat-indicating words becomes disrupted under conditions of dopamine reduction. Results show that only the ISE predicted attention/avoidance of threat-indicating words. In addition, the avoidance mechanism, as measured by the ISE and MCI, was not activated when regular smokers abstained from smoking.

  10. Avoidable waste management costs

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, K.; Burns, M.; Priebe, S.; Robinson, P.

    1995-01-01

    This report describes the activity based costing method used to acquire variable (volume dependent or avoidable) waste management cost data for routine operations at Department of Energy (DOE) facilities. Waste volumes from environmental restoration, facility stabilization activities, and legacy waste were specifically excluded from this effort. A core team consisting of Idaho National Engineering Laboratory, Los Alamos National Laboratory, Rocky Flats Environmental Technology Site, and Oak Ridge Reservation developed and piloted the methodology, which can be used to determine avoidable waste management costs. The method developed to gather information was based on activity based costing, which is a common industrial engineering technique. Sites submitted separate flow diagrams that showed the progression of work from activity to activity for each waste type or treatability group. Each activity on a flow diagram was described in a narrative, which detailed the scope of the activity. Labor and material costs based on a unit quantity of waste being processed were then summed to generate a total cost for that flow diagram. Cross-complex values were calculated by determining a weighted average for each waste type or treatability group based on the volume generated. This study will provide DOE and contractors with a better understanding of waste management processes and their associated costs. Other potential benefits include providing cost data for sites to perform consistent cost/benefit analysis of waste minimization and pollution prevention (WMIN/PP) options identified during pollution prevention opportunity assessments and providing a means for prioritizing and allocating limited resources for WMIN/PP.

  11. Incidence of plastic fragments among burrow-nesting seabird colonies on offshore islands in northern New Zealand.

    Science.gov (United States)

    Buxton, Rachel T; Currey, Caitlin A; Lyver, Philip O'B; Jones, Christopher J

    2013-09-15

    Marine plastic pollution is ubiquitous throughout the world's oceans, and has been found in high concentrations in oceanic gyres of both the northern and southern hemispheres. The number of studies demonstrating plastic debris at seabird colonies and plastic ingestion by adult seabirds has increased over the past few decades. Despite the recent discovery of a large aggregation of plastic debris in the South Pacific subtropical gyre, the incidence of plastics at seabird colonies in New Zealand is unknown. Between 2011 and 2012 we surveyed six offshore islands on the northeast coast of New Zealand's North Island for burrow-nesting seabird colonies and the presence of plastic fragments. We found non-research related plastic fragments (0.031 pieces/m(2)) on one island only, Ohinau, within dense flesh-footed shearwater (Puffinus carneipes) colonies. On Ohinau, we found a linear relationship between burrow density and plastic density, with 3.5 times more breeding burrows in areas with plastic fragments found. From these data we conclude that plastic ingestion is a potentially a serious issue for flesh-footed shearwaters in New Zealand. Although these results do not rule out plastic ingestion by other species, they suggest the need for further research on the relationship between New Zealand's pelagic seabirds and marine plastic pollution.

  12. Long-term monitoring study of beached seabirds shows that chronic oil pollution in the southern North Sea has almost halted.

    Science.gov (United States)

    Stienen, Eric W M; Courtens, Wouter; Van de Walle, Marc; Vanermen, Nicolas; Verstraete, Hilbran

    2017-02-15

    Trends in oil rates of beached seabirds reflect temporal and spatial patterns in chronic oil pollution at sea. We analysed a long-term dataset of systematic beached bird surveys along the Belgian North Sea coast during 1962-2015, where extreme high oil contamination rates and consequently high mortality rates of seabirds during the 1960s used to coincide with intensive ship traffic. In the 1960s, >90% of all swimming seabirds that washed ashore were contaminated with oil and estimated oil-induced mortality of seabirds was probably several times higher than natural mortality. More than 50years later oil rates of seabirds have dropped to historically low levels while shipping is still very intense, indicating that chronic oil pollution has significantly declined. The declining trend is discussed in the light of a series of legislative measures that were enacted in the North Sea region to reduce oil pollution.

  13. Highest PBDE levels (max 63 ppm) yet found in biota measured in seabird eggs from San Francisco Bay

    Energy Technology Data Exchange (ETDEWEB)

    She, J.; Holden, A.; Tanner, M.; Sharp, M.; Hooper, K. [Department of Toxic Substances Control, Berkeley, CA (United States). Hazardous Materials Lab.; Adelsbach, T. [Environmental Contaminants Division, Sacramento Fish and Wildlife Office, US Fish and Wildlife Service, Sacramento, CA (United States)

    2004-09-15

    High levels of polybrominated diphenylethers (PBDEs) have been found in humans and wildlife from the San Francisco Bay Area, with levels in women among the highest in the world, and levels in piscivorous seabird eggs at the ppm level. Seabirds are useful for monitoring and assessing ecosystem health at various times and places because they occupy a high trophic level in the marine food web, are long-lived, and are generally localized near their breeding and non-breeding sites. In collaboration with the US Fish and Wildlife Services (USFWS), we are carrying out a three-year investigation of dioxin, PCB and PBDE levels in eggs from fish-eating seabirds. Year 1 (2002) PBDE measurements from 73 bird eggs were reported at Dioxin2003. Year 2 (2003) PBDE measurements from 45 samples are presented in this report. The highest PBDE level measured in eggs was 63 ppm, lipid, which is the highest PBDE level, yet reported in biota.

  14. Patterns in prey use among fur seals and seabirds in the Pribilof Islands

    Science.gov (United States)

    Sinclair, E. H.; Vlietstra, L. S.; Johnson, D. S.; Zeppelin, T. K.; Byrd, G. V.; Springer, A. M.; Ream, R. R.; Hunt, G. L., Jr.

    2008-08-01

    We explored correlation in diet trends for five piscivorous predators that reproduce on the Pribilof Islands as illustrative of the shifting structure of the Bering Sea ecosystem. We evaluated the size and species of prey consumed by adult female and juvenile northern fur seals ( Callorhinus ursinus) and adults and chicks of black-legged kittiwakes ( Rissa tridactyla), red-legged kittiwakes ( Rissa brevirostris), thick-billed murres ( Uria lomvia), and common murres ( Uria aalge) from data collected between July and October 1960-2000. Sample sources included stomachs from seals and seabirds collected on pelagic foraging grounds in the eastern Bering Sea, seal scats from rookeries and seabird regurgitations and whole prey from nest sites on St. Paul and St. George Islands of the Pribilof Island archipelago. Typical prey included small fish and invertebrates (⩽20 cm for seals and ⩽12 cm for seabirds) that concentrate along frontal boundaries of the continental shelf/slope and in the epi-pelagic zone. Squids and fishes including walleye pollock ( Theragra chalcogramma), capelin ( Mallotus villosus), and sand lance ( Ammodytes hexapterus) were variably important in the diet of all five predators. Some prey, such as capelin, were principal in predator diets during the 1960s (seals) and into the early 1980s (seabirds), but declined or disappeared from all predator diets thereafter while others, such as walleye pollock, occurred with increasing frequency from the 1970s forward. As the number of individuals consuming walleye pollock increased, the overall volume of pollock in seabird diets declined. This decline was coincident with a decrease in the age and body size of pollock consumed by both seabirds and fur seals. Squid and pollock were negatively correlated in the diets of their primary consumers, northern fur seals (Pearson's coefficient -0.71, p=0.016) and thick-billed murres (Pearson's coefficient=-0.74, p=0.015) from the 1970s forward. Inter-island variation

  15. Avoidance Strategies in Intimate Relationships.

    Science.gov (United States)

    Belk, Sharyn S.; And Others

    Avoidance strategies involve the tactics and techniques people use when they don't wish to be influenced by others. To investigate the types of avoidance strategies men and women use to deal with an unwelcome persuasion attempt from an intimate partner, undergraduates wrote essays describing how they avoided such attempts. A 24-strategy coding…

  16. Influence of seabird colonies and other environmental variables on benthic community structure, Lancaster Sound Region, Canadian Arctic

    Science.gov (United States)

    Bouchard Marmen, Mariève; Kenchington, Ellen; Ardyna, Mathieu; Archambault, Philippe

    2017-03-01

    The Canadian Arctic shelters millions of seabirds each year during the breeding season. By the excretion of important quantities of guano, seabirds locally concentrate nutrient-rich organic matter in the marine areas surrounding colonies. Seabirds, acting as biological vectors of nutrients, can markedly affect terrestrial ecosystems, but their influence on the structure of marine benthic communities is still under-studied. Sessile and long-lived megabenthic species can integrate environmental variation into marine food webs over long time frames. The objectives of this study were (1) to characterize the epifaunal and infaunal communities of the Lancaster Sound Region (LSR) and (2) to test the influence of the presence of seabird colonies and other environmental parameters on the structure of those benthic communities. Our prediction was that benthic diversity, number of taxa, total biomass of infauna and total density of epifauna and infauna, would be higher in areas with colonies present. Photos of the seafloor (data on epifauna) and grab samples (data on infauna) were taken at three control areas and at five areas near seabird colonies, within a depth range of 122 to 442 m. A database of 26 environmental parameters was built to study the environment-benthos relationships. Infauna, which was relatively uniform across the LSR, was numerically dominated by Annelida. Epifauna was much patchier, with each study area having unique epibenthic assemblages. Brittle stars were highly abundant in epifaunal communities, reaching 600 individuals per square meter. The presence of seabird colonies was not a major driver of benthic community structure in the LSR at the depths studied. Negative effects of colonies were detected on the density and number of taxa of infauna, perhaps due to top-down effects transmitted by the seabirds which feed in the water column and can directly reduce the quantity of food reaching the seabed. Sediment concentration of pigment, percent cover of

  17. Estimating Regions of Oceanographic Importance for Seabirds Using A-Spatial Data.

    Directory of Open Access Journals (Sweden)

    Grant Richard Woodrow Humphries

    Full Text Available Advances in GPS tracking technologies have allowed for rapid assessment of important oceanographic regions for seabirds. This allows us to understand seabird distributions, and the characteristics which determine the success of populations. In many cases, quality GPS tracking data may not be available; however, long term population monitoring data may exist. In this study, a method to infer important oceanographic regions for seabirds will be presented using breeding sooty shearwaters as a case study. This method combines a popular machine learning algorithm (generalized boosted regression modeling, geographic information systems, long-term ecological data and open access oceanographic datasets. Time series of chick size and harvest index data derived from a long term dataset of Maori 'muttonbirder' diaries were obtained and used as response variables in a gridded spatial model. It was found that areas of the sub-Antarctic water region best capture the variation in the chick size data. Oceanographic features including wind speed and charnock (a derived variable representing ocean surface roughness came out as top predictor variables in these models. Previously collected GPS data demonstrates that these regions are used as "flyways" by sooty shearwaters during the breeding season. It is therefore likely that wind speeds in these flyways affect the ability of sooty shearwaters to provision for their chicks due to changes in flight dynamics. This approach was designed to utilize machine learning methodology but can also be implemented with other statistical algorithms. Furthermore, these methods can be applied to any long term time series of population data to identify important regions for a species of interest.

  18. High residue levels and the chemical form of mercury in tissues and organs of seabirds

    Energy Technology Data Exchange (ETDEWEB)

    Kim, E.Y.; Murakami, Toru; Saeki, Kazutoshi; Tatsukawa, Ryo [Ehime Univ. (Japan). Dept. of Environment Conservation

    1995-12-31

    Total and organic (methyl) mercury in liver, muscle, kidney and feather of 9 species of seabirds were analyzed to determine the levels and their distribution and to clarify the occurrences of high mercury levels and their detoxification process in seabirds. Total mercury levels in liver showed great variations in intra and interspecies, while organic mercury levels were less variable. As compared with species in relatively low mercury levels, the species which accumulated the high concentration of mercury like black-footed albatross exhibited the different distribution of mercury in the body: in total mercury burden, albatross species contained less than 10% in feather and over 50% in liver, while other species contained over 40% in feather and less than 20% in liver. The order of organic mercury concentrations in tissues were as follows: liver > kidney > muscle in seabirds examined, except oldsquaw. The mean percentage of organic mercury in total was 35%, 66%, and 36% in liver, muscle and kidney, respectively, for all the species. The significant negative correlations were found between organic mercury percentage to total mercury and total mercury concentrations in the liver and muscle of black-footed albatross and in the liver of laysan albatross. Furthermore, in liver, muscle, and kidney of all the species, the percentages of organic mercury had a negative trend with an increase of total mercury concentrations. The results suggest that albatross species may be capable for demethylating organic mercury in the tissues (mainly in liver), and for storing the mercury as immobilizable inorganic form in the liver as substitution for delivering organic mercury to other organs. It is noteworthy that the species with high degree of demethylation showed the lower mercury burdens in feather and slow moulting pattern.

  19. Sex-specific foraging behavior in response to fishing activities in a threatened seabird.

    Science.gov (United States)

    García-Tarrasón, Manuel; Bécares, Juan; Bateman, Santiago; Arcos, José Manuel; Jover, Lluís; Sanpera, Carolina

    2015-06-01

    Some seabird species have learnt to efficiently exploit fishing discards from trawling activities. However, a discard ban has been proposed as necessary in Europe to ensure the sustainability of the seas. It is of crucial importance for the management and conservation purposes to study the potential consequences of a discard ban on the foraging ecology of threatened seabirds. We assessed the influence of fishing activities on the feeding habits of 22 male and 15 female Audouin's gulls (Larus audouinii) from the Ebro Delta (Mediterranean Sea) during the breeding period using GPS loggers together with Stable Isotope Analysis (SIA), which provided new insights into their foraging behavior and trophic ecology, respectively. GPS data revealed different sex-specific foraging patterns between workdays and weekends. Females were highly consistent in that they foraged at sea throughout the week even though discarding stops at weekends. In contrast, males switched from foraging at sea during the week (when discards are produced) to an increased use of rice field habitats at weekends (when fishermen do not work). This sex-specific foraging behavior could be related to specific nutritional requirements associated with previous egg production, an energetically demanding period for females. However, on a broader time scale integrated by the SIA, both sexes showed a high degree of individual specialization in their trophic ecology. The need to obtain detailed information on the dependence and response of seabirds to fishing activities is crucial in conservation sciences. In this regard, sex-specific foraging behavior in relation to fisheries has been overlooked, despite the ecological and conservation implications. For instance, this situation may lead to sex differentiation in bycatch mortality in longlines when trawlers do not operate. Moreover, any new fisheries policy will need to be implemented gradually to facilitate the adaptation of a specialized species to a discard ban

  20. Pelagic seabird surveys in the Tuamotu and Gambier Archipelagos, French Polynesia

    Science.gov (United States)

    Vanderwerf, Eric A.; Pierce, Ray J.; Gill, Verena A.; Wragg, Graham; Raust, Philippe; Tibbitts, T. Lee

    2006-01-01

    We conducted pelagic seabird surveys in the Gambier and Tuamotu Archipelagos in the southeastern Pacific Ocean totaling 40 hours during 7-27 March 2003 and 22.5 hours during 22-27 July 2001. We used a 300-m-wide strip transect to estimate seabird density, and we estimated relative abundance of birds at all distances. In 2001, we observed a total of 326 birds of 18 species. The mean relative abundance of all birds was 14.3 ?? 3.1/h. Red-footed Booby Sula sula was the most abundant species (5.6/h), followed by White Tern Gygis alba (3.4/h), and Great Crested or Swift Tern Sterna bergii (1.2/h). In 2003, we observed a total of 1463 birds of 25 species. The mean relative abundance of all birds was 36.6 ?? 11.4/h and the mean density of all birds was 4.14 ?? 0.72/km2. Brown Noddy Anous stolidus was the most abundant species (17.6/h, 1.5/km2), followed by White Tern (8.4/h, 1.3/km2), and Red-footed Booby (4.6/h, 0.8/km2). Several globally or locally rare species were observed infrequently, including Phoenix Petrel Pterodroma alba (0.1/h, 0.03/km2). Distribution of birds was uneven, with long periods of no birds punctuated by occasional feeding flocks. In 2003, species diversity was related to length of observation period, with more species observed on longer segments (r2 = 0.58, F1.5 = 6.03, P = 0.05). Although the duration and extent of our surveys were limited, these data are valuable because little published information is available on pelagic seabirds in southeastern Polynesia.

  1. Foraging segregation and genetic divergence between geographically proximate colonies of a highly mobile seabird

    Science.gov (United States)

    Wiley, Anne E.; Welch, Andreanna J.; Ostrom, P.H.; James, Helen F.; Stricker, C.A.; Fleischer, R.C.; Gandhi, H.; Adams, J.; Ainley, D.G.; Duvall, F.; Holmes, N.; Hu, D.; Judge, S.; Penniman, J.; Swindle, K.A.

    2012-01-01

    Foraging segregation may play an important role in the maintenance of animal diversity, and is a proposed mechanism for promoting genetic divergence within seabird species. However, little information exists regarding its presence among seabird populations. We investigated genetic and foraging divergence between two colonies of endangered Hawaiian petrels (Pterodroma sandwichensis) nesting on the islands of Hawaii and Kauai using the mitochondrial Cytochrome b gene and carbon, nitrogen and hydrogen isotope values (?? 13C, ?? 15N and ??D, respectively) of feathers. Genetic analyses revealed strong differentiation between colonies on Hawaii and Kauai, with ?? ST = 0. 50 (p < 0. 0001). Coalescent-based analyses gave estimates of <1 migration event per 1,000 generations. Hatch-year birds from Kauai had significantly lower ?? 13C and ?? 15N values than those from Hawaii. This is consistent with Kauai birds provisioning chicks with prey derived from near or north of the Hawaiian Islands, and Hawaii birds provisioning young with prey from regions of the equatorial Pacific characterized by elevated ?? 15N values at the food web base. ?? 15N values of Kauai and Hawaii adults differed significantly, indicating additional foraging segregation during molt. Feather ??D varied from -69 to 53???. This variation cannot be related solely to an isotopically homogeneous ocean water source or evaporative water loss. Instead, we propose the involvement of salt gland excretion. Our data demonstrate the presence of foraging segregation between proximately nesting seabird populations, despite high species mobility. This ecological diversity may facilitate population coexistence, and its preservation should be a focus of conservation strategies. ?? 2011 Springer-Verlag (outside the USA).

  2. Accumulation of plastic-derived chemicals in tissues of seabirds ingesting marine plastics.

    Science.gov (United States)

    Tanaka, Kosuke; Takada, Hideshige; Yamashita, Rei; Mizukawa, Kaoruko; Fukuwaka, Masa-aki; Watanuki, Yutaka

    2013-04-15

    We analyzed polybrominated diphenyl ethers (PBDEs) in abdominal adipose of oceanic seabirds (short-tailed shearwaters, Puffinus tenuirostris) collected in northern North Pacific Ocean. In 3 of 12 birds, we detected higher-brominated congeners (viz., BDE209 and BDE183), which are not present in the natural prey (pelagic fish) of the birds. The same compounds were present in plastic found in the stomachs of the 3 birds. These data suggested the transfer of plastic-derived chemicals from ingested plastics to the tissues of marine-based organisms.

  3. A psychological perspective on tax avoidance: Deferential avoidance vs. defiant avoidance

    National Research Council Canada - National Science Library

    Minjo Kang

    2016-01-01

      Is a taxpayer's act of tax avoidance deemed compliant or non-compliant? Academic researchers, investigating tax compliance behaviour, address the term tax avoidance differently for a variety of purposes...

  4. Contrasting effects of tropical cyclones on the annual survival of a pelagic seabird in the Indian Ocean.

    Science.gov (United States)

    Nicoll, Malcolm A C; Nevoux, Marie; Jones, Carl G; Ratcliffe, Norman; Ruhomaun, Kevin; Tatayah, Vikash; Norris, Ken

    2017-02-01

    Tropical cyclones are renowned for their destructive nature and are an important feature of marine and coastal tropical ecosystems. Over the last 40 years, their intensity, frequency and tracks have changed, partly in response to ocean warming, and future predictions indicate that these trends are likely to continue with potential consequences for human populations and coastal ecosystems. However, our understanding of how tropical cyclones currently affect marine biodiversity, and pelagic species in particular, is limited. For seabirds, the impacts of cyclones are known to be detrimental at breeding colonies, but impacts on the annual survival of pelagic adults and juveniles remain largely unexplored and no study has simultaneously explored the direct impacts of cyclones on different life-history stages across the annual life cycle. We used a 20-year data set on tropical cyclones in the Indian Ocean, tracking data from 122 Round Island petrels and long-term capture-mark-recapture data to explore the impacts of tropical cyclones on the survival of adult and juvenile (first year) petrels during both the breeding and migration periods. The tracking data showed that juvenile and adult Round Island petrels utilize the three cyclone regions of the Indian Ocean and were potentially exposed to cyclones for a substantial part of their annual cycle. However, only juvenile petrel survival was affected by cyclone activity; negatively by a strong cyclone in the vicinity of the breeding colony and positively by increasing cyclone activity in the Northern Indian Ocean where they spend the majority of their first year at sea. These contrasting effects raise the intriguing prospect that the projected changes in cyclones under current climate change scenarios may have positive as well as the more commonly perceived negative impacts on marine biodiversity. © 2016 John Wiley & Sons Ltd.

  5. Oil pollution and climate have wide-scale impacts on seabird demographics.

    Science.gov (United States)

    Votier, Stephen C; Hatchwell, Ben J; Beckerman, Andrew; McCleery, Robin H; Hunter, Fiona M; Pellatt, Jayne; Trinder, Mark; Birkhead, Tim R

    2005-11-01

    Oil spills often spell disaster for marine birds caught in slicks. However, the impact of oil pollution on seabird population parameters is poorly known because oil spills usually occur in wintering areas remote from breeding colonies where birds may be distributed over a wide area, and because it is difficult to separate the effects of oil pollution from the effect of natural environmental variation on seabird populations. Using a long-term data set we show that over-winter survival of adult common guillemots (Uria aalge) is negatively affected by both the incidence of four major oil-spills in their wintering grounds and high values of the North Atlantic Oscillation (NAO) index. After controlling for the effect of the NAO index, we show that winter mortality of adult guillemots is doubled by major oil pollution incidents. Our results demonstrate that oil pollution can have wide-scale impacts on marine ecosystems that can be quantified using populations of marked individuals to estimate survival.

  6. Diving physiology of seabirds and marine mammals: Relevance, challenges and some solutions for field studies.

    Science.gov (United States)

    Andrews, Russel D; Enstipp, Manfred R

    2016-12-01

    To fully understand how diving seabirds and marine mammals balance the potentially conflicting demands of holding their breath while living their lives underwater (and maintaining physiological homeostasis during exercise, feeding, growth, and reproduction), physiological studies must be conducted with animals in their natural environments. The purpose of this article is to review the importance of making physiological measurements on diving animals in field settings, while acknowledging the challenges and highlighting some solutions. The most extreme divers are great candidates for study, especially in a comparative and mechanistic context. However, physiological data are also required of a wide range of species for problems relating to other disciplines, in particular ecology and conservation biology. Physiological data help with understanding and predicting the outcomes of environmental change, and the direct impacts of anthropogenic activities. Methodological approaches that have facilitated the development of field-based diving physiology include the isolated diving hole protocol and the translocation paradigm, and while there are many techniques for remote observation, animal-borne biotelemetry, or "biologging", has been critical. We discuss issues related to the attachment of instruments, the retrieval of data and sensing of physiological variables, while also considering negative impacts of tagging. This is illustrated with examples from a variety of species, and an in-depth look at one of the best studied and most extreme divers, the emperor penguin (Aptenodytes forsteri). With a variety of approaches and high demand for data on the physiology of diving seabirds and marine mammals, the future of field studies is bright.

  7. Low Density of Top Predators (Seabirds and Marine Mammals in the High Arctic Pack Ice

    Directory of Open Access Journals (Sweden)

    Claude R. Joiris

    2016-01-01

    Full Text Available The at-sea distribution of top predators, seabirds and marine mammals, was determined in the high Arctic pack ice on board the icebreaker RV Polarstern in July to September 2014. In total, 1,620 transect counts were realised, lasting 30 min each. The five most numerous seabird species represented 74% of the total of 15,150 individuals registered: kittiwake Rissa tridactyla, fulmar Fulmarus glacialis, puffin Fratercula arctica, Ross’s gull Rhodostethia rosea, and little auk Alle alle. Eight cetacean species were tallied for a total of 330 individuals, mainly white-beaked dolphin Lagenorhynchus albirostris and fin whale Balaenoptera physalus. Five pinniped species were represented by a total of 55 individuals and the polar bear Ursus maritimus was represented by 12 individuals. Four main geographical zones were identified: from Tromsø to the outer marginal ice zone (OMIZ, the Arctic pack ice (close pack ice, CPI, the end of Lomonosov Ridge off Siberia, and the route off Siberia and northern Norway. Important differences were detected between zones, both in species composition and in individual abundance. Low numbers of species and high proportion of individuals for some of them can be considered to reflect very low biodiversity. Numbers encountered in zones 2 to 4 were very low in comparison with other European Arctic seas. The observed differences showed strong patterns.

  8. The effects of spatially heterogeneous prey distributions on detection patterns in foraging seabirds.

    Directory of Open Access Journals (Sweden)

    Octavio Miramontes

    Full Text Available Many attempts to relate animal foraging patterns to landscape heterogeneity are focused on the analysis of foragers movements. Resource detection patterns in space and time are not commonly studied, yet they are tightly coupled to landscape properties and add relevant information on foraging behavior. By exploring simple foraging models in unpredictable environments we show that the distribution of intervals between detected prey (detection statistics is mostly determined by the spatial structure of the prey field and essentially distinct from predator displacement statistics. Detections are expected to be Poissonian in uniform random environments for markedly different foraging movements (e.g. Lévy and ballistic. This prediction is supported by data on the time intervals between diving events on short-range foraging seabirds such as the thick-billed murre (Uria lomvia. However, Poissonian detection statistics is not observed in long-range seabirds such as the wandering albatross (Diomedea exulans due to the fractal nature of the prey field, covering a wide range of spatial scales. For this scenario, models of fractal prey fields induce non-Poissonian patterns of detection in good agreement with two albatross data sets. We find that the specific shape of the distribution of time intervals between prey detection is mainly driven by meso and submeso-scale landscape structures and depends little on the forager strategy or behavioral responses.

  9. Spatial ecotoxicology: migratory Arctic seabirds are exposed to mercury contamination while overwintering in the northwest Atlantic.

    Science.gov (United States)

    Fort, Jérôme; Robertson, Gregory J; Grémillet, David; Traisnel, Gwendoline; Bustamante, Paco

    2014-10-01

    Arctic organisms are exposed to various levels of pollutants, among which mercury (Hg) has raised important environmental concerns. Previous studies examining Hg levels, trends, and effects on Arctic marine top predators have focused on the Arctic region. However, many of these top predators, such as seabirds, migrate to spend a large part of their life cycle far from the Arctic in areas where their exposure to contaminants is largely unknown. By combining biotelemetry and Hg and stable isotope analyses, we studied the seasonal Hg contamination of little auks (Alle alle, the most abundant Arctic seabird) in relation to their distribution and marine foraging habitat, as well as its potential impacts on bird reproduction. We show that little auks were ∼ 3.5 times more contaminated when outside the breeding season, and that Hg that accumulated during this nonbreeding non-Arctic period was related to egg size the following season, with females having more Hg laying smaller eggs. Our results highlight that ecotoxicological studies should be expanded to yield a comprehensive understanding of contamination risks and associated threats to top predators over their entire annual cycle. Furthermore, we show that an important nonbreeding area located in the northwest Atlantic was associated with greater Hg contamination and demonstrate the utility of bird-borne miniaturized technology for evaluating the contamination of marine systems on large spatial scales.

  10. Levels and pattern of polybrominated diphenyl ethers in eggs of Antarctic seabirds: Endemic versus migratory species

    Energy Technology Data Exchange (ETDEWEB)

    Yogui, G.T. [Geochemical and Environmental Research Group, College of Geosciences, Texas A and M University, 833 Graham Road, College Station, TX 77845 (United States)], E-mail: gtyogui@ocean.tamu.edu; Sericano, J.L. [Geochemical and Environmental Research Group, College of Geosciences, Texas A and M University, 833 Graham Road, College Station, TX 77845 (United States)], E-mail: jsericano@gerg.tamu.edu

    2009-03-15

    Chinstrap and gentoo penguins are endemic species that live year round south of the Antarctic Convergence. South polar skua is a migratory seabird that can be observed in Antarctica during the breeding season (i.e., austral summer). This study compares concentration and pattern of polybrominated diphenyl ethers (PBDEs) in eggs of seabirds breeding at King George Island, Antarctic Peninsula. PBDEs in south polar skua eggs are approximately 20 times higher than in penguin eggs suggesting that skuas are more exposed to contaminants during the non-breeding season when they migrate to waters of the northern hemisphere. The pattern of PBDE congeners also differs between south polar skua and penguin eggs. The latter exhibited a pattern similar to that found in the local biota. In contrast, the congener pattern in south polar skua eggs suggests that birds breeding at King George Island may winter in the northwestern Pacific Ocean. - Skua and penguin eggs collected at King George Island have different concentration and pattern of PBDEs.

  11. Seabird databases and the new paradigm for scientific publication and attribution

    Science.gov (United States)

    Hatch, Scott A.

    2010-01-01

    For more than 300 years, the peer-reviewed journal article has been the principal medium for packaging and delivering scientific data. With new tools for managing digital data, a new paradigm is emerging—one that demands open and direct access to data and that enables and rewards a broad-based approach to scientific questions. Ground-breaking papers in the future will increasingly be those that creatively mine and synthesize vast stores of data available on the Internet. This is especially true for conservation science, in which essential data can be readily captured in standard record formats. For seabird professionals, a number of globally shared databases are in the offing, or should be. These databases will capture the salient results of inventories and monitoring, pelagic surveys, diet studies, and telemetry. A number of real or perceived barriers to data sharing exist, but none is insurmountable. Our discipline should take an important stride now by adopting a specially designed markup language for annotating and sharing seabird data.

  12. Olieslachtoffers op de Nederlandse Kust, 2010/2011 = Oiled Seabirds Washing Ashore in the Netherlands, 2010/2011

    NARCIS (Netherlands)

    Camphuysen, K.C.J.

    2011-01-01

    This report presents the proportion of dead oiled birds washed ashore in TheNetherlands of the total number of birds washing ashore as a result of beachedbird surveys conducted by volunteers of the Dutch Seabird Group (NZG/NSO).Apart from the survey results for winter 2010/11, a summary is provided

  13. Contamination of an arctic terrestrial food web with marine-derived persistent organic pollutants transported by breeding seabirds

    Energy Technology Data Exchange (ETDEWEB)

    Choy, Emily S., E-mail: echoy087@uottawa.c [Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada); Kimpe, Linda E., E-mail: linda.kimpe@uottawa.c [Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada); Mallory, Mark L., E-mail: mark.mallory@ec.gc.c [Canadian Wildlife Service, Environment Canada, Iqaluit, NU, X0A 0H0 (Canada); Smol, John P., E-mail: smolj@queensu.c [Paleoecological Environmental Assessment and Research Lab (PEARL), Department of Biology, Queen' s University, Kingston, ON, K7L 3N6 (Canada); Blais, Jules M., E-mail: jules.blais@uottawa.c [Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada)

    2010-11-15

    At Cape Vera, Devon Island (Nunavut, Canada), a colony of northern fulmars (Fulmarus glacialis) concentrates and releases contaminants through their guano to the environment. We determined whether persistent organic pollutants (POPs) from seabirds were transferred to coastal food webs. Snow buntings (Plectrophenax nivalis) were the most contaminated species, with {Sigma}PCB and {Sigma}DDT (mean: 168, 106 ng/g ww) concentrations surpassing environmental guidelines for protecting wildlife. When examined collectively, PCB congeners and DDT in jewel lichen (Xanthoria elegans) were lower in samples taken farther from the seabird colony, and increased with increasing {delta}{sup 15}N values. However, only concentrations of p'p-DDE:{Sigma}DDT and PCB-95 were significantly correlated inversely with distance from the seabird cliffs. Linkages between marine-derived POPs and their concentrations in terrestrial mammals were less clear. Our study provides novel contaminant data for these species and supports biovector transport as a source of organic contaminants to certain components of the terrestrial food web. - This study provides evidence of contaminant transport by seabirds to a coastal Arctic food web.

  14. Responses of seabirds, in particular prions (Pachyptila sp.), to small-scale processes in the Antarctic Polar Front

    NARCIS (Netherlands)

    Franeker, van J.A.; Brink, van den N.W.; Bathmann, U.V.; Pollard, R.T.; Baar, de H.J.W.; Wolff, W.J.

    2002-01-01

    Small-scale distribution patterns of seabirds in the Antarctic Polar Front (APF) were investigated in relation to other biological, physical, and chemical features during the ANT-XIII/2 research cruise of R.V. Polarstern from December 1995 to January 1996. The APF is characterized by steep gradients

  15. Flight paths of seabirds soaring over the ocean surface enable measurement of fine-scale wind speed and direction.

    Science.gov (United States)

    Yonehara, Yoshinari; Goto, Yusuke; Yoda, Ken; Watanuki, Yutaka; Young, Lindsay C; Weimerskirch, Henri; Bost, Charles-André; Sato, Katsufumi

    2016-08-09

    Ocean surface winds are an essential factor in understanding the physical interactions between the atmosphere and the ocean. Surface winds measured by satellite scatterometers and buoys cover most of the global ocean; however, there are still spatial and temporal gaps and finer-scale variations of wind that may be overlooked, particularly in coastal areas. Here, we show that flight paths of soaring seabirds can be used to estimate fine-scale (every 5 min, ∼5 km) ocean surface winds. Fine-scale global positioning system (GPS) positional data revealed that soaring seabirds flew tortuously and ground speed fluctuated presumably due to tail winds and head winds. Taking advantage of the ground speed difference in relation to flight direction, we reliably estimated wind speed and direction experienced by the birds. These bird-based wind velocities were significantly correlated with wind velocities estimated by satellite-borne scatterometers. Furthermore, extensive travel distances and flight duration of the seabirds enabled a wide range of high-resolution wind observations, especially in coastal areas. Our study suggests that seabirds provide a platform from which to measure ocean surface winds, potentially complementing conventional wind measurements by covering spatial and temporal measurement gaps.

  16. Detecting change in seabird distributions at sea in arctic and sub-arctic waters over six decades

    DEFF Research Database (Denmark)

    Gjerdrum, Carina; Wong, Sarah; Johansen, Kasper Lambert

    In the western North Atlantic and eastern Arctic, data on the distribution and abundance of seabirds at sea have been collected by the Canadian Wildlife Service from two main survey programs using ships of opportunity. The first, PIROP (Programme intégré de recherches sur les oiseaux pélagiques...

  17. Stimulus conflict triggers behavioral avoidance.

    Science.gov (United States)

    Dignath, David; Eder, Andreas B

    2015-12-01

    According to a recent extension of the conflict-monitoring theory, conflict between two competing response tendencies is registered as an aversive event and triggers a motivation to avoid the source of conflict. In the present study, we tested this assumption. Over five experiments, we examined whether conflict is associated with an avoidance motivation and whether stimulus conflict or response conflict triggers an avoidance tendency. Participants first performed a color Stroop task. In a subsequent motivation test, participants responded to Stroop stimuli with approach- and avoidance-related lever movements. These results showed that Stroop-conflict stimuli increased the frequency of avoidance responses in a free-choice motivation test, and also increased the speed of avoidance relative to approach responses in a forced-choice test. High and low proportions of response conflict in the Stroop task had no effect on avoidance in the motivation test. Avoidance of conflict was, however, obtained even with new conflict stimuli that had not been presented before in a Stroop task, and when the Stroop task was replaced with an unrelated filler task. Taken together, these results suggest that stimulus conflict is sufficient to trigger avoidance.

  18. Avoiding integrity land mines.

    Science.gov (United States)

    Heineman, Ben W

    2007-04-01

    How does a large multinational keep thousands of employees, operating in hundreds of countries, honest in a high-pressure business environment? As the chief legal officer at General Electric for nearly 20 years, Ben Heineman was part of the senior management group that sought to do just that--to make sure its executives and employees are moved to do the right thing as strongly as they are motivated to make their numbers. Heineman describes a set of systems that combine the communication of clear expectations with oversight, deterrence, and incentives. Nowhere are the expectations higher--and the sanctions more powerful--than for top executives. Heineman recounts example after example of senior leaders terminated for ethical lapses even when the business consequences of doing so were painful--and even when they had no direct knowledge of the violations occurring on their watch. To make expectations clear throughout the company, GE has systematically sought to set uniform standards that stay well ahead of current legal developments and stakeholders' changing attitudes about corporate accountability. Responsibility for implementing those standards, which are embedded in GE's operating practices, rests with the business leaders in the field. Oversight is both methodical and multifaceted. A host of auditing and assessment systems enables GE to compare the performance of its various business units against one another and against industry benchmarks. Perhaps the most powerful is the company's ombudsman system, which doesn't just allow but requires employees to lodge concerns. Failures to report into the system or up the line, or retaliation in any form, are firing offenses. The current intense focus on board-level governance has missed the point, Heineman argues. It is time to shift the debate from board oversight of the CEO to how top company leaders can most effectively infuse integrity at all levels of the corporation.

  19. A changing distribution of seabirds in South Africa – the possible impact of climate and its consequences

    Directory of Open Access Journals (Sweden)

    Robert James Minchin Crawford

    2015-02-01

    Full Text Available In the southern Benguela ecosystem off South Africa, there were recent shifts to the south and east in the distributions of three forage resources (anchovy, sardine, rock lobster, which probably were influenced by environmental change although fishing too may have played a part. In this study, we review information on trends in distributions and numbers of eight seabirds breeding in South Africa. For five species that feed predominantly on anchovy, sardine or rock lobster, their populations off northwest South Africa decreased markedly. For three of these species, which exhibit behavioural inertia and have restricted foraging ranges when breeding (African penguin, Cape cormorant, bank cormorant, there were large decreases in their overall populations in South Africa. Conversely, for two showing more plasticity and able to range over wide areas or move between breeding localities (Cape gannet, swift tern there were increases. It is thought that movement of forage resources away from the northern islands led to a mismatch in the distributions of breeding localities and prey of dependent seabirds off western South Africa and to attempts by several species to establish colonies on the southern mainland closer to food resources. There also were shifts to the south and east in the distributions of three seabirds that do not compete with fisheries for prey (crowned cormorant, white-breasted cormorant, kelp gull, suggesting some environmental forcing, but decreases of these species off northwest South Africa were less severe and populations in South Africa remained stable or increased in the long term. It is likely, because many fishing plants are located in the northwest, that there was increased competition between seabirds and fisheries for prey as forage resources moved south and east. Potential interventions to mitigate the adverse impacts of distributional changes for seabirds include allocations of allowable catches of shared forage resources at

  20. Chemical avoidance responses of fishes.

    Science.gov (United States)

    Tierney, Keith B

    2016-05-01

    The hydrosphere is a repository for all of our waste and mistakes, be they sewage, garbage, process-affected waters, runoff, and gases. For fish living in environments receiving undesirable inputs, moving away seems an obvious way to avoid harm. While this should occur, there are numerous examples where it will not. The inability to avoid harmful environments may lead to sensory impairments that in turn limit the ability to avoid other dangers or locate benefits. For avoidance to occur, the danger must first be perceived, which may not happen if the fish is 'blinded' in some capacity. Second, the danger must be recognized for what it is, which may also not happen if the fish is cognitively confused or impaired. Third, it is possible that the fish may not be able to leave the area, or worse, learns to prefer a toxic environment. Concerning generating regulations around avoidance, there are two possibilities: that an avoidance threshold be used to set guidelines for effluent release with the intention of driving fishes away; the second is to set a contaminant concentration that would not affect the avoidance or attraction responses to other cues. With the complexities of the modern world in which we release diverse pollutants, from light to municipal effluents full of 1000s of chemicals, to the diversity present in ecosystems, it is impossible to have avoidance data on every stimulus-species combination. Nevertheless, we may be able to use existing avoidance response data to predict the likelihood of avoidance of untested stimuli. Where we cannot, this review includes a framework that can be used to direct new research. This review is intended to collate existing avoidance response data, provide a framework for making decisions in the absence of data, and suggest studies that would facilitate the prediction of risk to fish health in environments receiving intentional and unintentional human-based chemical inputs.

  1. An Examination of Avoided Costs in Utah

    Energy Technology Data Exchange (ETDEWEB)

    Bolinger, Mark; Wiser, Ryan

    2005-01-07

    The Utah Wind Working Group (UWWG) believes there are currently opportunities to encourage wind power development in the state by seeking changes to the avoided cost tariff paid to qualifying facilities (QFs). These opportunities have arisen as a result of a recent renegotiation of Pacificorp's Schedule 37 tariff for wind QFs under 3 MW, as well as an ongoing examination of Pacificorp's Schedule 38 tariff for wind QFs larger than 3 MW. It is expected that decisions made regarding Schedule 38 will also impact Schedule 37. Through the Laboratory Technical Assistance Program (Lab TAP), the UWWG has requested (through the Utah Energy Office) that LBNL provide technical assistance in determining whether an alternative method of calculating avoided costs that has been officially adopted in Idaho would lead to higher QF payments in Utah, and to discuss the pros and cons of this method relative to the methodology recently adopted under Schedule 37 in Utah. To accomplish this scope of work, I begin by summarizing the current method of calculating avoided costs in Utah (per Schedule 37) and Idaho (the ''surrogate avoided resource'' or SAR method). I then compare the two methods both qualitatively and quantitatively. Next I present Pacificorp's four main objections to the use of the SAR method, and discuss the reasonableness of each objection. Finally, I conclude with a few other potential considerations that might add value to wind QFs in Utah.

  2. Cigarette tax avoidance and evasion.

    Science.gov (United States)

    Stehr, Mark

    2005-03-01

    Variation in state cigarette taxes provides incentives for tax avoidance through smuggling, legal border crossing to low tax jurisdictions, or Internet purchasing. When taxes rise, tax paid sales of cigarettes will decline both because consumption will decrease and because tax avoidance will increase. The key innovation of this paper is to compare cigarette sales data to cigarette consumption data from the Behavioral Risk Factor Surveillance System (BRFSS). I show that after subtracting percent changes in consumption, residual percent changes in sales are associated with state cigarette tax changes implying the existence of tax avoidance. I estimate that the tax avoidance response to tax changes is at least twice the consumption response and that tax avoidance accounted for up to 9.6% of sales between 1985 and 2001. Because of the increase in tax avoidance, tax paid sales data understate the level of smoking and overstate the drop in smoking. I also find that the level of legal border crossing was very low relative to other forms of tax avoidance. If states have strong preferences for smoking control, they must pair high cigarette taxes with effective policies to curb smuggling and other forms of tax avoidance or employ alternative policies such as counter-advertising and smoking restrictions.

  3. Parental conflict and blue egg coloration in a seabird

    Science.gov (United States)

    Morales, Judith; Torres, Roxana; Velando, Alberto

    2010-02-01

    When both parents provide offspring care, equal sharing of costly parental duties may enhance reproductive success. This is crucial for longlived species, where increased parental effort in current reproduction profoundly affects future reproduction. Indication of reproductive value or willingness to invest in reproduction may promote matching responses by mates, thus reducing the conflict over care. In birds with biparental care, blue-green eggshell color may function as a signal of reproductive value that affects parental effort, as predicted by the signaling hypothesis of blue-green eggshell coloration. However, this hypothesis has not been explored during incubation, when the potential stimulus of egg color is present, and has been little studied in longlived birds. We experimentally studied if egg color affected incubation patterns in the blue-footed booby, a longlived species with biparental care and blue eggs. We exchanged fresh eggs between nests of the same laying date and recorded parental incubation effort on the following 4 days. Although egg color did not affect male effort, original eggshell color was correlated with pair matching in incubation. Exchanged eggshell color did not affect incubation patterns. This suggests that biliverdin-based egg coloration reflects female quality features that are associated with pair incubation effort or that blue-footed boobies mate assortatively high-quality pairs incubating more colorful clutches. An intriguing possibility is that egg coloration facilitates an equal sharing of incubation, the signal being functional only during a short period close to laying. Results also suggest that indication of reproductive value reduces the conflict over care.

  4. Converging evidence of social avoidant behavior in schizophrenia from two approach-avoidance tasks.

    Science.gov (United States)

    de la Asuncion, Javier; Docx, Lise; Sabbe, Bernard; Morrens, Manuel; de Bruijn, Ellen R A

    2015-10-01

    Many people with schizophrenia suffer from social impairments characterized by active social avoidance, which is related to social phobia common in schizophrenia, while motivational impairments can also result in passive social withdrawal. Although social avoidance is frequently reported in this population, this is the first study to directly compare approach-avoidance tendencies in schizophrenia patients (N = 37) and healthy controls (N = 29). Participants performed two tasks: a computerized approach-avoidance task (AAT) to assess response tendencies toward images of happy and angry faces with direct or averted gaze and a one-to-one personal space test (PST) to gauge more naturalistic approach-avoidance behaviors toward a real person bearing a neutral expression. The AAT results showed that both groups showed faster avoidance responses to angry faces and faster approach responses to happy faces with a direct gaze. Happy faces with averted gaze, however, resulted in faster avoidance responses in the patient group only. On the PST, the patients approached the experimenter less than healthy controls did. This measure of interpersonal distance was positively related to positive symptom severity. Delusions of reference and increased sensitivity to social rejection may explain the patients' avoidance tendencies in response to pictures of happy faces with averted gaze and in the presence of an actual person. The current findings demonstrate the importance of others adopting positive and unambiguous attitudes when interacting with schizophrenia patients to minimize behavioral avoidance patterns, which is particularly relevant for relatives and clinicians whose interactions with the patients are crucial to facilitating treatment and promoting healthy social relationships.

  5. NOAA ESRI Grid - predictions of relative seabird abundance in the New York offshore planning area made by the NOAA Biogeography Branch

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents relative seabird abundance predictions from spatial models developed for the New York offshore spatial planning area. This raster was derived...

  6. NOAA ESRI Grid - predictions of relative uncertainty for seabird diversity metrics in the New York offshore planning area by NOAA Biogeography Branch

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents relative seabird abundance predictions from spatial models developed for the New York offshore spatial planning area. This raster was derived...

  7. A reconnaissance of the breeding distribution of colonial nesting of seabirds on the south coast of the Alaska Peninsula, May 30 - June 19, 1973

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These field notes respond to the need for more knowledge about colonial seabirds, a neglected segment of Alaska's natural resources. Refuges, research and what was...

  8. NCCOS Assessment: Predictive Mapping of Seabirds, Pinnipeds and Cetaceans off the Pacific Coast of Washington from 1995-07-21 to 2015-12-08 (NCEI Accession 0148762)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data collection comprises seasonal distribution maps and model outputs of selected seabird, pinniped and cetacean species off the Pacific coast of Washington....

  9. Atlantic Offshore Seabird Dataset Catalog, Atlantic Coast and Outer Continental Shelf, from 1938-01-01 to 2013-12-31 (NODC Accession 0115356)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Several bureaus within the Department of Interior compiled available information from seabird observation datasets from the Atlantic Outer Continental Shelf into a...

  10. NOAA ESRI Grid - predictions of seabird species richness in the New York offshore planning area made by the NOAA Biogeography Branch

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents seabird species richness, or number of species, predictions from spatial models developed for the New York offshore spatial planning area....

  11. Modeled prevalance of seabirds and relative abundance of cetaceans in NW Atlantic (limit-40 W) from 1980-04-01 to 1988-10-01 (NCEI Accession 0130025)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set is a compilation of modeled seabird prevalence predictions for a selection of species including Razorbill (Alca torda), Greater Shearwater (Puffinus...

  12. Feather mercury concentrations in Southern Ocean seabirds: Variation by species, site and time.

    Science.gov (United States)

    Becker, Peter H; Goutner, Vassilis; Ryan, Peter G; González-Solís, Jacob

    2016-09-01

    We studied mercury contamination in 25 seabird species breeding along a latitudinal gradient across the Southern Ocean, from Gough Island (40°S) through Marion Island (47°S) to Byers Peninsula (63°S). Total mercury concentrations in body feather samples of adults caught at breeding colonies from 2008 to 2011 were determined. Krill (Euphausia spp.) and other zooplankton consumers had low mercury concentrations (gentoo penguin Pygoscelis papua, chinstrap penguin Pseudomonas Antarctica, common diving petrel Pelecanoides urinatrix, broad-billed prion Pachyptila vittata; mean levels 308-753 ng g(-1)), whereas seabirds consuming squid or carrion had high mercury concentrations (ascending order: Kerguelen petrel Aphrodroma brevirostris, southern giant petrel Macronectes giganteus, soft-plumaged petrel Pterodroma mollis, sooty albatross Phoebetria fusca, Atlantic petrel Pterodroma incerta, northern giant petrel Macronectes halli, great-winged petrel Pterodroma macroptera; 10,720-28038 ng g(-1)). The two species with the highest mercury concentrations, northern giant petrels and great-winged petrels, bred at Marion Island. Among species investigated at multiple sites, southern giant petrels had higher mercury levels at Marion than at Gough Island and Byers Peninsula. Mercury levels among Byers Peninsula seabirds were low, in two species even lower than levels measured 10 years before at Bird Island, South Georgia. Replicate measurements after about 25 years at Gough Island showed much higher mercury levels in feathers of sooty albatrosses (by 187%), soft-plumaged petrels (53%) and Atlantic petrels (49%). Concentrations similar to the past were detected in southern giant petrels at Gough and Marion islands, and in northern giant petrels at Marion. There were no clear indications that timing of moult or migratory behavior affected mercury contamination patterns among species. Causes of inter-site or temporal differences in mercury contamination could not be verified

  13. A new approach to study of seabird-fishery overlap: Connecting chick feeding with parental foraging and overlap with fishing vessels

    OpenAIRE

    Junichi Sugishita; Leigh G Torres; Philip J Seddon

    2015-01-01

    Incidental fisheries bycatch is recognised as a major threat to albatross populations worldwide. However, fishery discards and offal produced in large quantities might benefit some scavenging seabirds. Here, we demonstrate an integrated approach to better understand the ecological ramifications of fine-scale overlap between seabirds and fisheries. As a case study, we examined whether foraging in association with a fishing vessel is advantageous for chick provisioning in terms of quantity of f...

  14. Ground Collision Avoidance System (Igcas)

    Science.gov (United States)

    Skoog, Mark A (Inventor); Prosser, Kevin (Inventor); Hook, Loyd (Inventor)

    2017-01-01

    The present invention is a system and method for aircraft ground collision avoidance (iGCAS) comprising a modular array of software, including a sense own state module configured to gather data to compute trajectory, a sense terrain module including a digital terrain map (DTM) and map manger routine to store and retrieve terrain elevations, a predict collision threat module configured to generate an elevation profile corresponding to the terrain under the trajectory computed by said sense own state module, a predict avoidance trajectory module configured to simulate avoidance maneuvers ahead of the aircraft, a determine need to avoid module configured to determine which avoidance maneuver should be used, when it should be initiated, and when it should be terminated, a notify Module configured to display each maneuver's viability to the pilot by a colored GUI, a pilot controls module configured to turn the system on and off, and an avoid module configured to define how an aircraft will perform avoidance maneuvers through 3-dimensional space.

  15. Pattern Avoidance in Ternary Trees

    CERN Document Server

    Gabriel, Nathan; Pudwell, Lara; Tay, Samuel

    2011-01-01

    This paper considers the enumeration of ternary trees (i.e. rooted ordered trees in which each vertex has 0 or 3 children) avoiding a contiguous ternary tree pattern. We begin by finding recurrence relations for several simple tree patterns; then, for more complex trees, we compute generating functions by extending a known algorithm for pattern-avoiding binary trees. Next, we present an alternate one-dimensional notation for trees which we use to find bijections that explain why certain pairs of tree patterns yield the same avoidance generating function. Finally, we compare our bijections to known "replacement rules" for binary trees and generalize these bijections to a larger class of trees.

  16. New at-sea records of pelagic seabirds in the South Atlantic Ocean and Antarctica

    Directory of Open Access Journals (Sweden)

    José Luis Orgeira

    2013-05-01

    Full Text Available During ship-based seabird surveys in the south Atlantic and Antarctica in the austral summers of 1994/95, 2009, 2010, 2011 and 2012, we documented at-sea distributions of Buller's albatross (Thalassarche bulleri, Atlantic petrel (Pterodroma incerta, soft-plumaged petrel (Pterodroma mollis, Kerguelen petrel (Lugensa brevirostris and great-winged petrel (Pterodroma macroptera. In some cases, sightings were considered as extralimital, but for other species updating their distributions in the literature seems warranted. Atlantic petrel, for example, has been regularly observed in the Drake Passage and north of the Antarctic Peninsula for about 30 years, but the distribution of this species has not been updated in the literature. The observations reported here will contribute to update the at-sea distributions of these species and to changes in their distributions.

  17. Mate replacement entails a fitness cost for a socially monogamous seabird

    Science.gov (United States)

    Ismar, Stefanie M. H.; Daniel, Claire; Stephenson, Brent M.; Hauber, Mark E.

    2010-01-01

    Studies of the selective advantages of divorce in socially monogamous bird species have unravelled extensive variation among different lineages with diverse ecologies. We quantified the reproductive correlates of mate retention, mate loss and divorce in a highly philopatric, colonially breeding biparental seabird, the Australasian gannet Morus serrator. Estimates of annual divorce rates varied between 40-43% for M. serrator and were high in comparison with both the closely related Morus bassanus and the range of divorce rates reported across monogamous avian breeding systems. Mate retention across seasons was related to consistently higher reproductive success compared with mate replacement, while divorce per se contributed significantly to lower reproductive output only in one of two breeding seasons. Prior reproductive success was not predictive of mate replacement overall or divorce in particular. These patterns are in accordance with the musical chairs hypothesis of adaptive divorce theory, which operates in systems characterised by asynchronous territorial establishment.

  18. Mercury accumulation in sediments and seabird feathers from the Antarctic Peninsula.

    Science.gov (United States)

    Calle, Paola; Alvarado, Omar; Monserrate, Lorena; Cevallos, Juan Manuel; Calle, Nastenka; Alava, Juan José

    2015-02-28

    In an effort to assess the impact of mercury in the Antarctic Peninsula, we conducted ecotoxicological research in this region during the summer of 2012 and 2013. The objectives were to assess: (a) mercury levels in sediment samples; (b) mercury accumulation in Antarctic seabird feathers: Catharacta lonnbergi (brown skua), Pygoscelis papua (gentoo penguin) and Pygoscelis antarctica (chinstrap penguin); and (c) biomagnification (BMF predator/prey) and biota sediment accumulation (BSAF skuas/sediment) factors. Mercury concentrations in sediment were relatively low. Mercury concentrations were significantly higher in brown skuas and gentoo penguins than in chinstrap penguins (2012), and significantly higher in brown skuas than in both penguins (2013). BMF indicated 2-7.5 times greater mercury levels in brown skuas than in penguins. BSAF values suggested an apparent temporal decrease of 18.2% of this ratio from 2012 to 2013. Long-range environmental transport is the likely route of entry of mercury into the Antarctic Peninsula.

  19. Seabirds of Easter Island, Salas y Gómez Island and Desventuradas Islands, southeastern Pacific Ocean

    Directory of Open Access Journals (Sweden)

    Marcelo A Flores

    2014-10-01

    Full Text Available We reviewed available information on seabirds inhabiting Easter Island, Salas y Gómez Island and Desventuradas Islands and their adjacent waters through an analysis of published and grey literature. Results obtained indicate that a total of 37 species are present in the study area and that, among the orders represented, the Procellariiformes and Charadriiformes are the dominant taxa (29 species. Moreover, the family Procellariidae is represented by 13 species and Laridae by 7 species. There has been an increase in new records over the past six years but no systematic studies have been developed. The need for further research that focuses on ecological aspects and anthropogenic impacts is critical in order to develop adequate conservation strategies.

  20. Attraction of Hawaiian seabirds to lights: conservation efforts and effects of moon phase

    Science.gov (United States)

    Telfer, T.C.; Sincock, J.L.; Byrd, G.V.; Reed, J.R.

    1987-01-01

    Increased urban lighting on Kauai Island, Hawaii, has resulted in new problems for threatened and endangered procellariiform birds. Between 1978 and 1985,11,767 Kewell's shearwaters, 38 dark-rumped petrels, and 8 band-rumped storm petrels were attracted to bright urban lights, struck unseen objects, and fell to the ground. A salvage effort involving public cooperation and government-run 'aid stations' has returned 90% of these birds to the wild. Nightly fallout of seabirds was significantly reduced during the full moon, but fallout increased as the new moon approached. The heaviest fallout occurred in urban coastal areas, particularly at river mouths. More than 97% of the fallout involved fledgling birds apparently leaving their mountain nesting grounds for the first time. Less than 1%of these birds were recovered again on subsequent nights.

  1. The importance of tidewater glaciers for marine mammals and seabirds in Svalbard, Norway

    Science.gov (United States)

    Lydersen, Christian; Assmy, Philipp; Falk-Petersen, Stig; Kohler, Jack; Kovacs, Kit M.; Reigstad, Marit; Steen, Harald; Strøm, Hallvard; Sundfjord, Arild; Varpe, Øystein; Walczowski, Waldek; Weslawski, Jan Marcin; Zajaczkowski, Marek

    2014-01-01

    Approximately 60% of Svalbard's land areas are glaciated at the present time. The Archipelago has more than 1100 glaciers (> 1 km2) and 163 of these are “tidewater glaciers” - that is glaciers that terminate (with their calving front) at the sea. It has been known for a long time that these glacier front areas are important feeding areas for seabirds and marine mammals. Herein, we review current knowledge regarding the importance of these areas for these animals and reflect upon the processes that create these apparent “hotspots”. Kittiwakes Rissa tridactyla, routinely dominate avian assemblages in front of glaciers in Svalbard, but fulmars Fulmarus glacialis, ivory gulls Pagophila eburnea and glaucous gulls Larus hyperboreus also contribute to aggregations, which can sometimes comprise many thousands of individuals. The birds are often found in the so-called “brown zone”, which is an area in front of tidewater glaciers that is ice-free due to currents and muddy due to suspended sediments. Animals at these sites typically have their stomachs full of large zooplankton or fish. These brown zones are also foraging hotspots for Svalbard's ringed seals (Pusa hispida) and white whales (Delphinapterus leucas). Prime breeding habitat for ringed seals in Svalbard occurs deep in the fjords where ice pieces calved from the glacier fronts become frozen into land-fast sea-ice, promoting the accumulation of snow to a depth suitable for ringed seal females to dig out birth lairs above breathing holes in the ice. These pupping areas are important hunting areas for polar bears (Ursus maritimus) in spring, especially female bears with cubs of the year during the period following emergence from the winter/birthing den. Glacier-ice pieces floating in coastal areas are also important for all seal species in the region as dry platforms during moulting and also as general resting platforms for both birds and seals. During the last decade there have been several years with a

  2. Oil pollution increases plasma antioxidants but reduces coloration in a seabird.

    Science.gov (United States)

    Pérez, Cristóbal; Lores, Marta; Velando, Alberto

    2010-08-01

    It has been suggested that condition-dependent signals may be a useful measure of environmental quality. In this study, we tested the hypothesis that oil pollution enhances oxidative stress and impairs expression of a carotenoid-based signal in a wild population of the yellow-legged gull (Larus michahellis). During the courtship period, a group of gulls were fed a supplementary diet containing heavy fuel oil from the Prestige oil spill and were compared with control gulls fed a similar supplementary diet without fuel oil. Blood levels of polycyclic aromatic hydrocarbons, the most toxic components of crude oils, were higher (30%) in the Prestige oil-fed gulls than in the control gulls. Plasma concentrations of vitamin E and carotenoids were also significantly higher in the Prestige oil-fed gulls (31 and 27%, respectively). Although, the plasma levels of lipid peroxidation markers were higher (13%) in gulls fed with Prestige oil than in the control gulls, these differences were not significant, possibly because of the small number of gulls analyzed. The red bill spot was significantly smaller (16%) in the oil-fed gulls than in the control individuals. This study provides the first experimental evidence that a carotenoid-based signal in a free-living seabird is affected by exposure to oil pollution and is hence indicative of environmental quality. Since the yellow-legged gull belongs to a complex of species widely distributed throughout the northern hemisphere, the method described may constitute a useful tool for evaluating sub-lethal effects of oil spills in seabirds.

  3. Studying seabird diet through genetic analysis of faeces: a case study on macaroni penguins (Eudyptes chrysolophus.

    Directory of Open Access Journals (Sweden)

    Bruce E Deagle

    Full Text Available BACKGROUND: Determination of seabird diet usually relies on the analysis of stomach-content remains obtained through stomach flushing; this technique is both invasive and logistically difficult. We evaluate the usefulness of DNA-based faecal analysis in a dietary study on chick-rearing macaroni penguins (Eudyptes chrysolophus at Heard Island. Conventional stomach-content data was also collected, allowing comparison of the approaches. METHODOLOGY/PRINCIPAL FINDINGS: Prey-specific PCR tests were used to detect dietary DNA in faecal samples and amplified prey DNA was cloned and sequenced. Of the 88 faecal samples collected, 39 contained detectable DNA from one or more of the prey groups targeted with PCR tests. Euphausiid DNA was most commonly detected in the early (guard stage of chick-rearing, and detection of DNA from the myctophid fish Krefftichthys anderssoni and amphipods became more common in samples collected in the later (crèche stage. These trends followed those observed in the penguins' stomach contents. In euphausiid-specific clone libraries the proportion of sequences from the two dominant euphausiid prey species (Euphausia vallentini and Thysanoessa macrura changed over the sampling period; again, this reflected the trend in the stomach content data. Analysis of prey sequences in universal clone libraries revealed a higher diversity of fish prey than identified in the stomachs, but non-fish prey were not well represented. CONCLUSIONS/SIGNIFICANCE: The present study is one of the first to examine the full breadth of a predator's diet using DNA-based faecal analysis. We discuss methodological difficulties encountered and suggest possible refinements. Overall, the ability of the DNA-based approach to detect temporal variation in the diet of macaroni penguins indicates this non-invasive method will be generally useful for monitoring population-level dietary trends in seabirds.

  4. Studying seabird diet through genetic analysis of faeces: a case study on macaroni penguins (Eudyptes chrysolophus).

    Science.gov (United States)

    Deagle, Bruce E; Gales, Nick J; Evans, Karen; Jarman, Simon N; Robinson, Sarah; Trebilco, Rowan; Hindell, Mark A

    2007-09-05

    Determination of seabird diet usually relies on the analysis of stomach-content remains obtained through stomach flushing; this technique is both invasive and logistically difficult. We evaluate the usefulness of DNA-based faecal analysis in a dietary study on chick-rearing macaroni penguins (Eudyptes chrysolophus) at Heard Island. Conventional stomach-content data was also collected, allowing comparison of the approaches. Prey-specific PCR tests were used to detect dietary DNA in faecal samples and amplified prey DNA was cloned and sequenced. Of the 88 faecal samples collected, 39 contained detectable DNA from one or more of the prey groups targeted with PCR tests. Euphausiid DNA was most commonly detected in the early (guard) stage of chick-rearing, and detection of DNA from the myctophid fish Krefftichthys anderssoni and amphipods became more common in samples collected in the later (crèche) stage. These trends followed those observed in the penguins' stomach contents. In euphausiid-specific clone libraries the proportion of sequences from the two dominant euphausiid prey species (Euphausia vallentini and Thysanoessa macrura) changed over the sampling period; again, this reflected the trend in the stomach content data. Analysis of prey sequences in universal clone libraries revealed a higher diversity of fish prey than identified in the stomachs, but non-fish prey were not well represented. The present study is one of the first to examine the full breadth of a predator's diet using DNA-based faecal analysis. We discuss methodological difficulties encountered and suggest possible refinements. Overall, the ability of the DNA-based approach to detect temporal variation in the diet of macaroni penguins indicates this non-invasive method will be generally useful for monitoring population-level dietary trends in seabirds.

  5. Use of social information in seabirds: compass rafts indicate the heading of food patches.

    Directory of Open Access Journals (Sweden)

    Henri Weimerskirch

    Full Text Available Ward and Zahavi suggested in 1973 that colonies could serve as information centres, through a transfer of information on the location of food resources between unrelated individuals (Information Centre Hypothesis. Using GPS tracking and observations on group movements, we studied the search strategy and information transfer in two of the most colonial seabirds, Guanay cormorants (Phalacrocorax bougainvillii and Peruvian boobies (Sula variegata. Both species breed together and feed on the same prey. They do return to the same feeding zone from one trip to the next indicating high unpredictability in the location of food resources. We found that the Guanay cormorants use social information to select their bearing when departing the colony. They form a raft at the sea surface whose position is continuously adjusted to the bearing of the largest returning columns of cormorants. As such, the raft serves as a compass signal that gives an indication on the location of the food patches. Conversely, Peruvian boobies rely mainly on personal information based on memory to take heading at departure. They search for food patches solitarily or in small groups through network foraging by detecting the white plumage of congeners visible at long distance. Our results show that information transfer does occur and we propose a new mechanism of information transfer based on the use of rafts off colonies. The use of rafts for information transfer may be common in central place foraging colonial seabirds that exploit short lasting and/or unpredictably distributed food patches. Over the past decades Guanay cormorants have declined ten times whereas Peruvian boobies have remained relatively stable. We suggest that the decline of the cormorants could be related to reduced social information opportunities and that social behaviour and search strategies have the potential to play an important role in the population dynamics of colonial animals.

  6. Mercury concentrations in seabird tissues from Machias Seal Island, New Brunswick, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Bond, Alexander L., E-mail: abond@mun.ca [Atlantic Cooperative Wildlife Ecology Research Network, University of New Brunswick, PO Box 4400, Fredericton, New Brunswick, E3B 5A3 (Canada); Department of Biology, University of New Brunswick, PO Box 4400, Fredericton, New Brunswick, E3B 5A3 (Canada); Diamond, Antony W. [Atlantic Cooperative Wildlife Ecology Research Network, University of New Brunswick, PO Box 4400, Fredericton, New Brunswick, E3B 5A3 (Canada); Department of Biology, University of New Brunswick, PO Box 4400, Fredericton, New Brunswick, E3B 5A3 (Canada)

    2009-07-01

    Mercury is a pervasive environmental contaminant, the anthropogenic portion of which is increasing globally, and in northeastern North America in particular. Seabirds frequently are used as indicators of the marine environment, including mercury contamination. We analysed paired samples for total mercury (Hg) concentrations in feathers and blood from adult and chick, albumen, and lipid-free yolk of seven seabirds breeding on Machias Seal Island, New Brunswick, Canada - Arctic Tern (Sterna paradisaea), Atlantic Puffin (Fratercula arctica), Common Eider (Somateria mollissima), Common Murre (Uria aalge), Common Tern (Sterna hirundo), Leach's Storm-petrel (Oceanodroma leucorhoa), and Razorbill (Alca torda). We also used stable-isotope ratios of carbon ({delta}{sup 13}C), and nitrogen ({delta}{sup 15}N) to evaluate the relationship between carbon source and trophic position and mercury. We found high Hg concentrations across tissue types in Leach's Storm-petrels, and Razorbills, with lower concentrations in other species, the lowest being in Common Eiders. Storm-petrels prey on mesopelagic fish that accumulate mercury, and Razorbills feed on larger, older fish that bioaccumulate heavy metals. Biomagnification of Hg, or the increase in Hg concentration with trophic position as measured by {delta}{sup 15}N, was significant and greater in albumen than other tissues, whereas in other tissues, {delta}{sup 15}N explained little of the overall variation in Hg concentration. Hg concentrations in egg components are higher on Machias Seal Island than other sites globally and in the Gulf of Maine region, but only for some species. Further detailed investigations are required to determine the cause of this trend.

  7. Keeping it regular: Development of thermoregulation in four tropical seabird species.

    Science.gov (United States)

    Hart, Lorinda A; Downs, Colleen T; Brown, Mark

    2017-02-01

    The thermoregulatory capacity of a species can determine which climatic niche it occupies. Its development in avian chicks is influenced by numerous factors. Furthermore, it is suggested that altricial chicks develop their thermoregulatory capacity post-hatching, while precocial chicks develop aspects of this in the egg. We investigated the development of thermoregulation of four co-occurring seabird species in the Seychelles; namely white, ground-nesting white-tailed tropicbirds (Phaethon lepturus) and tree-nesting fairy terns (Gygis alba); and dark plumaged, tree-nesting lesser noddies (Anous tenuirostris) and ground- and tree-nesting brown noddies (A. stolidus). White-tailed tropicbirds have semi-altricial chicks, while the remaining species have semi-precocial chicks. Cloacal temperatures (Tb) were measured at five day intervals from newly hatched chicks and compared over time, and with adult Tbs. Initial Tbs of all chicks, except fairy terns, were lower than those taken when chicks were older. Brooding cessation generally coincided with feather development, as did an increase in Tb. Mean chick Tb was significantly lower than mean adult Tb for all species, but only white-tailed tropicbird and brown noddy chicks in tree nests differed significantly from mean adult Tb when chick Tb at five day intervals were considered. There was a significant interactive effect of nest site and age on brown noddy chick Tb, but chick colour did not have a significant effect on Tb. However, brown noddy chicks on dune crests maintained a constant Tb sooner than chicks in tree nests. Our results demonstrate that tropical seabird species have a more delayed onset of thermoregulatory capabilities when compared with those in temperate environments, perhaps as nest sites are less thermally challenging. Nest microhabitats and behavioural thermoregulation, are likely more important during early chick development for these species. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Feather corticosterone reveals stress associated with dietary changes in a breeding seabird.

    Science.gov (United States)

    Will, Alexis; Watanuki, Yutaka; Kikuchi, Dale M; Sato, Nobuhiko; Ito, Motohiro; Callahan, Matt; Wynne-Edwards, Katherine; Hatch, Scott; Elliott, Kyle; Slater, Leslie; Takahashi, Akinori; Kitaysky, Alexander

    2015-10-01

    Changes in climate and anthropogenic pressures might affect the composition and abundance of forage fish in the world's oceans. The junk-food hypothesis posits that dietary shifts that affect the quality (e.g., energy content) of food available to marine predators may impact their physiological state and consequently affect their fitness. Previously, we experimentally validated that deposition of the adrenocortical hormone, corticosterone, in feathers is a sensitive measure of nutritional stress in seabirds. Here, we use this method to examine how changes in diet composition and prey quality affect the nutritional status of free-living rhinoceros auklets (Cerorhinca monocerata). Our study sites included the following: Teuri Is. Japan, Middleton Is. central Gulf of Alaska, and St. Lazaria Is. Southeast Alaska. In 2012 and 2013, we collected "bill loads" delivered by parents to feed their chicks (n = 758) to document dietary changes. We deployed time-depth-temperature recorders on breeding adults (n = 47) to evaluate whether changes in prey coincided with changes in foraging behavior. We measured concentrations of corticosterone in fledgling (n = 71) and adult breeders' (n = 82) feathers to determine how birds were affected by foraging conditions. We found that seasonal changes in diet composition occurred on each colony, adults dove deeper and engaged in longer foraging bouts when capturing larger prey and that chicks had higher concentrations of corticosterone in their feathers when adults brought back smaller and/or lower energy prey. Corticosterone levels in feathers of fledglings (grown during the breeding season) and those in feathers of adult breeders (grown during the postbreeding season) were positively correlated, indicating possible carryover effects. These results suggest that seabirds might experience increased levels of nutritional stress associated with moderate dietary changes and that physiological responses to changes in prey composition

  9. Things to Avoid When Breastfeeding

    Science.gov (United States)

    ... need to avoid fish that are high in mercury, namely, shark, swordfish, king mackerel, and tilefish. When you do eat fish, it’s important to eat varieties that contain less mercury, such as canned light tuna, shrimp, salmon, pollock, ...

  10. Neuromorphic UAS Collision Avoidance Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Using biologically-inspired neuromorphic optic flow algorithms is a novel approach in collision avoidance for UAS. Traditional computer vision algorithms rely on...

  11. Avoiding Gluten Cross-Contamination

    Science.gov (United States)

    ... Toddler For Preschooler For Gradeschooler For Teen Avoiding Gluten Cross-Contamination Reviewed by Sharon Denny, MS, RDN ... can be a virtual mine field. That's because gluten (a protein in grains such as wheat, rye ...

  12. Robot Avoids Collisions With Obstacles

    Science.gov (United States)

    Cheung, Edward; Rosinski, Doug; Wegerif, Dan

    1993-01-01

    Developmental robot equipped with infrared sensors and control system acting in concert to enable manipulator arm to move around obstacles. Robot avoids collisions with other objects, even when moving in unpredictable ways. Control system requires no prior knowledge of environment.

  13. How to avoid exercise injuries

    Science.gov (United States)

    ... gov/ency/patientinstructions/000859.htm How to avoid exercise injuries To use the sharing features on this ... injury and stay safe during exercise. What Causes Exercise Injuries? Some of the most common causes of ...

  14. Postcopulatory inbreeding avoidance in guppies

    National Research Council Canada - National Science Library

    Fitzpatrick, J. L; Evans, J. P

    2014-01-01

    .... Here, we examine the potential for paternity biases to favour unrelated males when their sperm compete for fertilizations though postcopulatory inbreeding avoidance mechanisms in the guppy, P oecilia reticulata...

  15. Vision-based obstacle avoidance

    Science.gov (United States)

    Galbraith, John

    2006-07-18

    A method for allowing a robot to avoid objects along a programmed path: first, a field of view for an electronic imager of the robot is established along a path where the electronic imager obtains the object location information within the field of view; second, a population coded control signal is then derived from the object location information and is transmitted to the robot; finally, the robot then responds to the control signal and avoids the detected object.

  16. Oiled seabird rescue at the J.V. Fitzgerald Marine Reserve, San Mateo County, California, 1968-1995

    Science.gov (United States)

    Carter, H.R.

    1997-01-01

    Records of oiled and injured seabirds at the J.V. Fitzgerald Marine Reserve, San Mateo County, California, were collated from the daily log at the Reserve for the period 1968-1995. These records serve to demonstrate that oil spills and chronic oiling have occurred frequently in this area, just south of San Francisco. Common Murres (Uria aalge) were the most frequently-oiled species rescued at the Reserve. Greater efforts should be made by wildlife rehabilitators to collate large volumes of past data (prior to the early 1990s) on oiled and injured seabirds for similar documentation of large or moderate oil spills (including undocumented or poorly-known spills), chronic oiling from small spills, and injuries from other sources.

  17. Approach/avoidance in dreams.

    Science.gov (United States)

    Malcolm-Smith, Susan; Koopowitz, Sheri; Pantelis, Eleni; Solms, Mark

    2012-03-01

    The influential threat simulation theory (TST) asserts that dreaming yields adaptive advantage by providing a virtual environment in which threat-avoidance may be safely rehearsed. We have previously found the incidence of biologically threatening dreams to be around 20%, with successful threat avoidance occurring in approximately one-fifth of such dreams. TST asserts that threat avoidance is over-represented relative to other possible dream contents. To begin assessing this issue, we contrasted the incidence of 'avoidance' dreams with that of their opposite: 'approach' dreams. Because TST states that the threat-avoidance function is only fully activated in ecologically valid (biologically threatening) contexts, we also performed this contrast for populations living in both high- and low-threat environments. We find that 'approach' dreams are significantly more prevalent across both contexts. We suggest these results are more consistent with the view that dreaming is generated by reward-seeking systems than by fear-conditioning systems, although reward-seeking is clearly not the only factor determining the content of dreams.

  18. Monitoring polycyclic aromatic hydrocarbon pollution in the marine environment after the Prestige oil spill by means of seabird blood analysis.

    Science.gov (United States)

    Pérez, Cristóbal; Velando, Alberto; Munilla, Ignacio; López-Alonso, Marta; Oro, Daniel

    2008-02-01

    In this study we tested the use of seabird blood as a bioindicator of polycyclic aromatic hydrocarbon (PAH) pollution in the marine environment. Blood cells of breeding yellow-legged gulls (Larus michahellis) were able to track spatial and temporal changes consistent with the massive oil pollution pulse that resulted from the Prestige oil spill. Thus, in 2004, blood samples from yellow-legged gulls breeding in colonies that were in the trajectory of the spill doubled in theirtotal PAH concentrations when compared to samples from unoiled colonies. Furthermore, PAH levels in gulls from an oiled colony decreased by nearly a third in two consecutive breeding seasons (2004 and 2005). Experimental evidence was gathered by means of an oil-ingestion field experiment. The total concentration of PAHs in the blood of gulls given oil supplements was 30% higher compared to controls. This strongly suggested that measures of PAHs in the blood of gulls are sensitive to the ingestion of small quantities of oil. Our study provides evidence that seabirds were exposed to residual Prestige oil 17 months after the spill commenced and gives support to the nondestructive use of seabirds as biomonitors of oil pollution in marine environments.

  19. Nesting seabirds in SE Spain: distribution, numbers and trends in the province of Almería

    Directory of Open Access Journals (Sweden)

    Mariano Paracuellos

    2003-07-01

    Full Text Available Little is known on the abundance of seabirds breeding in southeastern Spain. This study reports on the distribution, numbers and population trends of breeding colonies of this avian group in this region. Principally from 1996 to 2000, the coast of the province of Almería was surveyed during the breeding season. In 2000, the last year of survey, we counted 1,731 seabird breeding pairs, corresponding to 8 species. The yellow-legged gull Larus cachinnans was the most abundant seabird with more than 50% of the total, followed by Audouin´s gull Larus audouinii, the little tern Sterna albifrons, the black-headed gull Larus ridibundus and the common tern Sterna hirundo. Cory´s shearwater Calonectris diomedea, the shag Phalacrocorax aristotelis and the European storm petrel Hydrobates pelagicus bred in small numbers. The black-headed Gull, yellow-legged gull and common tern showed increasing trends over the last decade. The most important breeding sites were Alborán Island and the sea cliffs of Cabo de Gata, La Higuera and Cabrera. A main factor influencing increasing population trends was the lack of human disturbance at legally protected breeding sites.

  20. Responses of seabirds, in particular prions ( Pachyptila sp.), to small-scale processes in the Antarctic Polar Front

    Science.gov (United States)

    van Franeker, Jan A.; van den Brink, Nico W.; Bathmann, Ulrich V.; Pollard, Raymond T.; de Baar, Hein J. W.; Wolff, Wim J.

    Small-scale distribution patterns of seabirds in the Antarctic Polar Front (APF) were investigated in relation to other biological, physical, and chemical features during the ANT-XIII/2 research cruise of R.V. Polarstern from December 1995 to January 1996. The APF is characterized by steep gradients in sea-surface temperature and salinity. Within the APF, gradient zones were closely associated with elevated levels of primary production, chlorophyll- a (chl- a) concentrations, and zooplankton densities. Even broad-billed prions (' Pachyptila vittata-group'), which dominated the seabird community by 83% in carbon requirements, showed small-scale distributional patterns that were positively related to primary production, chl- a, and total zooplankton densities. The findings demonstrate a close, direct link between fine-scale physical processes in the APF and biological activity through several food web levels up to that of zooplankton-eating seabirds. Broad-billed prions appeared to forage on very small copepods ( Oithona spp.) in close association with the front. Fish- and squid-eating predators showed poor correlations with small-scale spatial structures of the APF. However, in a wider band around the APF, most top predators did occur in elevated densities, showing gradual spatio-temporal diffusion of the impact of the APF on higher trophic levels.

  1. Black Petrels (Procellaria parkinsoni patrol the ocean shelf-break: GPS tracking of a vulnerable procellariiform seabird.

    Directory of Open Access Journals (Sweden)

    Robin Freeman

    Full Text Available BACKGROUND: Determining the foraging movements of pelagic seabirds is fundamental for their conservation. However, the vulnerability and elusive lifestyles of these animals have made them notoriously difficult to study. Recent developments in satellite telemetry have enabled tracking of smaller seabirds during foraging excursions. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report the first successful precision tracking of a c. 700 g seabird, the vulnerable Black Petrel, Procellaria parkinsoni, foraging at sea during the breeding season, using miniature GPS-logging technology. Employing a combination of high-resolution fixes and low-power duty-cycles, we present data from nine individual foraging excursions tracked during the chick-rearing period in February 2006. CONCLUSIONS/SIGNIFICANCE: We provide a snapshot of the species' foraging range and behaviour in relation to detailed underlying bathymetry off the coast of New Zealand, finding a significant relationship between foraging movements and regions of the shelf-break. We also highlight the potential of more sophisticated analyses to identify behavioural phenomena from position data alone.

  2. Motive to Avoid Success, Locus of Control, and Reinforcement Avoidance.

    Science.gov (United States)

    Katovsky, Walter

    Subjects were four groups of 12 college women, high or low in motive to avoid success (MAS) and locus of control (LC), were reinforced for response A on a fixed partial reinforcement schedule on three concept learning tasks, one task consisting of combined reward and punishment, another of reward only, and one of punishment only. Response B was…

  3. Using large scale surveys to investigate seasonal variations in seabird distribution and abundance. Part II: The Bay of Biscay and the English Channel

    Science.gov (United States)

    Pettex, Emeline; Laran, Sophie; Authier, Matthieu; Blanck, Aurélie; Dorémus, Ghislain; Falchetto, Hélène; Lambert, Charlotte; Monestiez, Pascal; Stéfan, Eric; Van Canneyt, Olivier; Ridoux, Vincent

    2017-07-01

    Seabird distributions and the associated seasonal variations remain challenging to investigate, especially in oceanic areas. Recent advances in telemetry have provided considerable information on seabird ecology, but still exclude small species, non-breeding birds and individuals from inaccessible colonies from any scientific survey. To overcome this issue and investigate seabird distribution and abundance in the eastern North Atlantic (ENA), large-scale aerial surveys were conducted in winter 2011-12 and summer 2012 over a 375,000 km2 area encompassing the English Channel (EC) and the Bay of Biscay (BoB). Seabird sightings, from 15 taxonomic groups, added up to 17,506 and 8263 sightings in winter and summer respectively, along 66,307 km. Using geostatistical methods, density maps were provided for both seasons. Abundance was estimated by strip transect sampling. Most taxa showed marked seasonal variations in their density and distribution. The highest densities were recorded during winter for most groups except shearwaters, storm-petrels, terns and large-sized gulls. Subsequently, the abundance in winter nearly reached one million individuals and was 2.5 times larger than in summer. The continental shelf and the slope in the BoB and the EC were identified as key areas for seabird conservation, especially during winter, as birds from northern Europe migrate southward after breeding. This large-scale study provided a synoptic view of the seabird community in the ENA, over two contrasting seasons. Our results highlight that oceanic areas harbour an abundant avifauna. Since most of the existing marine protected areas are restricted to the coastal fringe, the importance of oceanic areas in winter should be considered in future conservation plans. Our work will provide a baseline for the monitoring of seabird distribution at sea, and could inform the EU Marine Strategy Framework Directive.

  4. Contrasting population trends of piscivorous seabirds in the Pribilof Islands: A 30-year perspective

    Science.gov (United States)

    Byrd, G. Vernon; Schmutz, Joel A.; Renner, Heather M.

    2008-08-01

    The Pribilof Islands provide nesting habitat for one of the largest concentrations of piscivorous seabirds in the North Pacific region. Pribilof breeding populations of black-legged and red-legged kittiwakes ( Rissa tridactyla and Rissa brevirostris), and common and thick-billed murres ( Uria aalge and Uria lomvia) are supported by a highly productive marine food web. Productivity and temperature in this area are influenced by winter sea ice that frequently reaches its maximum extent near the Pribilofs. Although St. George and St. Paul islands, the two largest of the Pribilof group, are situated only 60 km apart, St. George is within 25 km of the shelf break, but St. Paul is approximately 90 km away. In contrast, the local contribution of sea ice-edge productivity in the spring is frequently closer to St. Paul than to St. George. Central place foraging piscivorous seabirds nesting at St. Paul and St. George are likely differentially affected by the relative contributions of the shelf break and ice-edge environments based on juxtaposition. Within the past decade or so, sea ice in the Bering Sea has failed to reach the vicinity of the Pribilofs in some years, and predictions of warming in the future suggest the possibility that direct effects of the ice on the immediate Pribilof environment will be reduced. To evaluate the response of kittiwakes and murres on the two islands to conditions in their foraging environments, we examined population trends over the past 30 years based on data from the seabird monitoring program conducted by the Alaska Maritime National Wildlife Refuge and others. Spatial differences in trends have been more consistent than differences among species, with populations at St. Paul having more enduring declines than those at St. George. At St. George, black-legged kittiwakes and common murres have remained stable. Red-legged kittiwakes and thick-billed murres both declined, but began to rebound in the late 1980s, such that in 2005 population

  5. Contrasting population trends of piscivorous seabirds in the Pribilof Islands: A 30-year perspective

    Science.gov (United States)

    Byrd, G.V.; Schmutz, J.A.; Renner, H.M.

    2008-01-01

    The Pribilof Islands provide nesting habitat for one of the largest concentrations of piscivorous seabirds in the North Pacific region. Pribilof breeding populations of black-legged and red-legged kittiwakes (Rissa tridactyla and Rissa brevirostris), and common and thick-billed murres (Uria aalge and Uria lomvia) are supported by a highly productive marine food web. Productivity and temperature in this area are influenced by winter sea ice that frequently reaches its maximum extent near the Pribilofs. Although St. George and St. Paul islands, the two largest of the Pribilof group, are situated only 60 km apart, St. George is within 25 km of the shelf break, but St. Paul is approximately 90 km away. In contrast, the local contribution of sea ice-edge productivity in the spring is frequently closer to St. Paul than to St. George. Central place foraging piscivorous seabirds nesting at St. Paul and St. George are likely differentially affected by the relative contributions of the shelf break and ice-edge environments based on juxtaposition. Within the past decade or so, sea ice in the Bering Sea has failed to reach the vicinity of the Pribilofs in some years, and predictions of warming in the future suggest the possibility that direct effects of the ice on the immediate Pribilof environment will be reduced. To evaluate the response of kittiwakes and murres on the two islands to conditions in their foraging environments, we examined population trends over the past 30 years based on data from the seabird monitoring program conducted by the Alaska Maritime National Wildlife Refuge and others. Spatial differences in trends have been more consistent than differences among species, with populations at St. Paul having more enduring declines than those at St. George. At St. George, black-legged kittiwakes and common murres have remained stable. Red-legged kittiwakes and thick-billed murres both declined, but began to rebound in the late 1980s, such that in 2005 population

  6. Avoiding unfavourable outcomes in liposuction.

    Science.gov (United States)

    Khanna, Atul; Filobbos, George

    2013-05-01

    The origin of liposuction can be traced to an adverse event by Dujarrier in 1921 when he used a uterine curette to remove fat from the knees of a ballerina ending in an amputation secondary to damage of the femoral artery. The history of liposuction since then has been one of avoiding complications and optimising outcome. After this adverse event, liposuction was abandoned until the 1960's when Schrudde revived the practice using small stab incisions and sharp curettage with the secondary suction to aspirate the freed tissue. This technique was associated with a high incidence of complications especially seroma and skin necrosis. Illouz then replaced the curette with a blunt cannula connected to vacuum pump thus avoiding the complications of a sharp curette. Despite the presence of various techniques for liposuction, suction assisted liposuction (SAL) is still the standard technique of liposuction. This article aims to discuss literature regarding the various aspects of liposuction (SAL) and to highlight the salient points in the literature and in the senior author's experience in order to avoid unfavourable outcomes in liposuction. A literature review on avoiding complication is in liposuction including some of the seminal papers on liposuction. Liposuction is generally a safe procedure with reproducible outcome. Just like any surgical procedure it should be treated with the utmost care. Illouz published 10 commandments for liposuction in 1989 and we review these commandments to demonstrate how liposuction has evolved.

  7. Avoiding unfavourable outcomes in liposuction

    Directory of Open Access Journals (Sweden)

    Atul Khanna

    2013-01-01

    Full Text Available The origin of liposuction can be traced to an adverse event by Dujarrier in 1921 when he used a uterine curette to remove fat from the knees of a ballerina ending in an amputation secondary to damage of the femoral artery. The history of liposuction since then has been one of avoiding complications and optimising outcome. After this adverse event, liposuction was abandoned until the 1960′s when Schrudde revived the practice using small stab incisions and sharp curettage with the secondary suction to aspirate the freed tissue. This technique was associated with a high incidence of complications especially seroma and skin necrosis. Illouz then replaced the curette with a blunt cannula connected to vacuum pump thus avoiding the complications of a sharp curette. Despite the presence of various techniques for liposuction, suction assisted liposuction (SAL is still the standard technique of liposuction. This article aims to discuss literature regarding the various aspects of liposuction (SAL and to highlight the salient points in the literature and in the senior author′s experience in order to avoid unfavourable outcomes in liposuction. A literature review on avoiding complication is in liposuction including some of the seminal papers on liposuction. Liposuction is generally a safe procedure with reproducible outcome. Just like any surgical procedure it should be treated with the utmost care. Illouz published 10 commandments for liposuction in 1989 and we review these commandments to demonstrate how liposuction has evolved.

  8. Avoidance: grammatical or semantic causes?

    NARCIS (Netherlands)

    Hulstijn, J.H.; Marchena, E.

    1989-01-01

    This article follows up on a study by Dagut and Laufer (1985), who found that Hebrew learners of English avoid phrasal verbs, such as ‘let down’, while preferring one-word verbs, such as ‘;disappoint’, since phrasal verbs do not exist in Hebrew. A corollary derived from Dagut and Laufer's study is t

  9. Avoidance: grammatical or semantic causes?

    NARCIS (Netherlands)

    Hulstijn, J.H.; Marchena, E.

    1989-01-01

    This article follows up on a study by Dagut and Laufer (1985), who found that Hebrew learners of English avoid phrasal verbs, such as ‘let down’, while preferring one-word verbs, such as ‘;disappoint’, since phrasal verbs do not exist in Hebrew. A corollary derived from Dagut and Laufer's study is t

  10. Avoiding plagiarism in academic writing.

    Science.gov (United States)

    Anderson, Irene

    Plagiarism means taking the work of another and presenting it as one's own, resulting in potential upset for the original author and disrepute for the professions involved. This article aims to explore the issue of plagiarism and some mechanisms for detection and avoidance.

  11. Chlorinated biphenyls and pesticides in migrating and resident seabirds from East and West Antarctica.

    Science.gov (United States)

    Corsolini, Simonetta; Borghesi, Nicoletta; Ademollo, Nicoletta; Focardi, Silvano

    2011-11-01

    The unhatched eggs of the following seabirds were analyzed to quantify PCBs, hexachlorobenzene (HCB), α-, β-, γ-, δ-hexachlorocyclohexanes (HCHs), o,p' and p,p' isomers of DDT, DDD and DDE: resident Adèlie (Pygoscelis adèliae, ADPE) and Emperor (Aptenodytes forsteri, EMPE) penguins, migrating snow petrel (Pagodroma nivea, SNPT) and South Polar skua (Catharacta maccormicki, SPSK) from the Ross Sea (East Antarctica); and migrating Brown skua (Catharacta antartica, BRSK) and resident ADPE from the Brainsfield Strait (West Antarctica). The general aims were to evaluate the contaminant accumulation in eggs of migrating and resident species in the two study areas, and to compare levels in penguins and skuas nesting in East and West Antarctica. PCB congener and HCH and DDT isomer profiles were also assessed. Comparisons were evaluated using seven PCB congeners (IUPAC nos. 28, 52, 101, 118+149, 138, 153, and 180), p,p'-DDE, ΣDDTs, and ΣHCHs. Higher contaminant concentrations were detected in migrating seabirds (South polar skua and brown skua)>sub-Antarctic species (snow petrel)>Antarctic species (penguins) from both the sampling sites, suggesting contamination events at lower latitudes for those birds migrating northward. HCHs showed the lowest concentrations in all species (from 0.03±0.03 ng/g wet wt in SPSK to 1.81±1.23 ng/g wet wt in ADPE from West Antarctica), and PCBs were the most abundant contaminants (from 4.34±2.15 ng/g wet wt. in EMPE to 53.41±19.61 ng/g wet wt. in brown skua). Among pesticides, it is relevant the detection of p,p'-DDT in Adèlie penguin from West Antarctica and in both species of skua; the detection of this pesticide can confirm its actual use in certain malaria-endemic countries from where it is transferred through the long range transport to the polar regions. Contaminants did not show any significant temporal trend during a ten year time span, from 1994/95 to 2004/05, in organisms collected in East Antarctica and they did not

  12. Knowing and Avoiding Plagiarism During Scientific Writing

    Science.gov (United States)

    Kumar, P Mohan; Priya, N Swapna; Musalaiah, SVVS; Nagasree, M

    2014-01-01

    Plagiarism has become more common in both dental and medical communities. Most of the writers do not know that plagiarism is a serious problem. Plagiarism can range from simple dishonesty (minor copy paste/any discrepancy) to a more serious problem (major discrepancy/duplication of manuscript) when the authors do cut-copy-paste from the original source without giving adequate credit to the main source. When we search databases like PubMed/MedLine there is a lot of information regarding plagiarism. However, it is still a current topic of interest to all the researchers to know how to avoid plagiarism. It's time to every young researcher to know ethical guidelines while writing any scientific publications. By using one's own ideas, we can write the paper completely without looking at the original source. Specific words from the source can be added by using quotations and citing them which can help in not only supporting your work and amplifying ideas but also avoids plagiarism. It is compulsory to all the authors, reviewers and editors of all the scientific journals to know about the plagiarism and how to avoid it by following ethical guidelines and use of plagiarism detection software while scientific writing. PMID:25364588

  13. Urban water restrictions: Attitudes and avoidance

    Science.gov (United States)

    Cooper, Bethany; Burton, Michael; Crase, Lin

    2011-12-01

    In most urban cities across Australia, water restrictions remain the dominant policy mechanism to restrict urban water consumption. The extensive adoption of water restrictions as a means to limit demand, over several years, means that Australian urban water prices have consistently not reflected the opportunity cost of water. Given the generally strong political support for water restrictions and the likelihood that they will persist for some time, there is value in understanding households' attitudes in this context. More specifically, identifying the welfare gains associated with avoiding urban water restrictions entirely would be a nontrivial contribution to our knowledge and offer insights into the benefits of alternative policy responses. This paper describes the results from a contingent valuation study that investigates consumers' willingness to pay to avoid urban water restrictions. Importantly, the research also investigates the influence of cognitive and exogenous dimensions on the utility gain associated with avoiding water restrictions. The results provide insights into the impact of the current policy mechanism on economic welfare.

  14. Knowing and avoiding plagiarism during scientific writing.

    Science.gov (United States)

    Kumar, P Mohan; Priya, N Swapna; Musalaiah, Svvs; Nagasree, M

    2014-09-01

    Plagiarism has become more common in both dental and medical communities. Most of the writers do not know that plagiarism is a serious problem. Plagiarism can range from simple dishonesty (minor copy paste/any discrepancy) to a more serious problem (major discrepancy/duplication of manuscript) when the authors do cut-copy-paste from the original source without giving adequate credit to the main source. When we search databases like PubMed/MedLine there is a lot of information regarding plagiarism. However, it is still a current topic of interest to all the researchers to know how to avoid plagiarism. It's time to every young researcher to know ethical guidelines while writing any scientific publications. By using one's own ideas, we can write the paper completely without looking at the original source. Specific words from the source can be added by using quotations and citing them which can help in not only supporting your work and amplifying ideas but also avoids plagiarism. It is compulsory to all the authors, reviewers and editors of all the scientific journals to know about the plagiarism and how to avoid it by following ethical guidelines and use of plagiarism detection software while scientific writing.

  15. Granting silence to avoid wireless collisions

    KAUST Repository

    Choi, Jung Il

    2010-10-01

    We describe grant-to-send, a novel collision avoidance algorithm for wireless mesh networks. Rather than announce packets it intends to send, a node using grant-to-send announces packets it expects to hear others send. We present evidence that inverting collision avoidance in this way greatly improves wireless mesh performance. Evaluating four protocols from 802.11 meshes and 802.15.4 sensor networks, we find that grant-to-send matches or outperforms CSMA and RTS/CTS in all cases. For example, in a 4-hop UDP flow, grantto- send can achieve 96% of the theoretical maximum throughput while maintaining a 99.9% packet delivery ratio. Grant-tosend is also general enough to replace protocol-specific collision avoidance mechanisms common to sensor network protocols. Grant-to-send is simple. For example, incorporating it into 802.11 requires only 11 lines of driver code and no hardware changes. Furthermore, as it reuses existing 802.11 mechanisms, grant-to-send inter-operates with current networks and can be incrementally deployed. © 2010 IEEE.

  16. Dining Dovekies Demand, "When, Where and What's for Dinner?" The Impact of Seasonal Changes in Snow Melt and the Development of the Arctic Marine Food Web on Seabirds.

    Science.gov (United States)

    Karnovsky, N. J.; Harding, A.; Welcker, J.; Brown, Z. W.; Kitaysky, A.; Kwasniewski, S.; Walkusz, W.; Gremillet, D.

    2011-12-01

    The Atlantic sector of the Arctic is undergoing widespread climate change with increases in air and sea temperatures which impact the timing of ice retreat, snow melt and the development of the marine food web. Dovekies (Alle alle) are small seabirds that migrate to the Atlantic Sector of the Arctic to feed in ice free waters that have abundant lipid-rich zooplankton. In the Greenland Sea, the dovekies are largely dependent on the advection of Calanus copepods into the area. We hypothesized that dovekies breeding adjacent to water masses which bring smaller, less energy-rich prey into the region (Calanus finmarchicus), work harder to find food and have higher stress levels. We tested this hypothesis by attaching time-depth recorders to provisioning dovekies at three colonies adjacent to different water masses (the West Spistbergen Current, the East Greenland Current, and the Sorkapp Current). We determined the length of time dovekies at different colonies spent at-sea collecting food for themselves and their chicks. We measured circulating corticosteroid hormone levels in their blood to assess stress levels. We collected chick meals to determine the energetic content of prey fed chicks at the different colonies. We found that dovekies are sensitive to the quality of prey available to them. Dovekies exposed to less profitable prey made longer foraging trips and worked harder while at-sea to collect prey for themselves and their chicks. Furthermore, over the past 50 years, dovekies breeding along the western shores of Spitsbergen have initiated breeding earlier in spring as their nest sites have become snow-free at earlier dates. We evaluate the impact of earlier breeding and the timing of the development of the marine food web within different currents which advect and/or support Calanus copepods into the Greenland Sea. Future possible declines in dovekies may impact terrestrial food webs which are highly influenced by the annual input of nitrogen rich guano on the

  17. Thyroid hormones correlate with resting metabolic rate, not daily energy expenditure, in two charadriiform seabirds

    Directory of Open Access Journals (Sweden)

    Kyle H. Elliott

    2013-04-01

    Thyroid hormones affect in vitro metabolic intensity, increase basal metabolic rate (BMR in the lab, and are sometimes correlated with basal and/or resting metabolic rate (RMR in a field environment. Given the difficulty of measuring metabolic rate in the field—and the likelihood that capture and long-term restraint necessary to measure metabolic rate in the field jeopardizes other measurements—we examined the possibility that circulating thyroid hormone levels were correlated with RMR in two free-ranging bird species with high levels of energy expenditure (the black-legged kittiwake, Rissa tridactyla, and thick-billed murre, Uria lomvia. Because BMR and daily energy expenditure (DEE are purported to be linked, we also tested for a correlation between thyroid hormones and DEE. We examined the relationships between free and bound levels of the thyroid hormones thyroxine (T4 and triiodothyronine (T3 with DEE and with 4-hour long measurements of post-absorptive and thermoneutral resting metabolism (resting metabolic rate; RMR. RMR but not DEE increased with T3 in both species; both metabolic rates were independent of T4. T3 and T4 were not correlated with one another. DEE correlated with body mass in kittiwakes but not in murres, presumably owing to the larger coefficient of variation in body mass during chick rearing for the more sexually dimorphic kittiwakes. We suggest T3 provides a good proxy for resting metabolism but not DEE in these seabird species.

  18. Skin pentosidine and telomere length do not covary with age in a long-lived seabird.

    Science.gov (United States)

    Rattiste, Kalev; Klandorf, Hillar; Urvik, Janek; Sepp, Tuul; Asghar, Muhammad; Hasselquist, Dennis; Cooey, Crissa; Hõrak, Peeter

    2015-08-01

    The questions about why and how senescence occurs in the wild are among the most pertinent ones in evolutionary ecology. Telomere length is a commonly used marker for aging, while other biomarkers of aging have received considerably less attention. Here we studied how another potent indicator of aging-skin pentosidine concentration-relates to age and blood telomere length in a long-lived seabird with well-documented reproductive senescence. We found no associations between telomere length, skin pentosidine and chronological age in male common gulls (Larus canus), aging from 2 to 30 years. However, the variance in telomere length was 4.6 times higher among the birds older than 13 years, which hints at relaxed selection on telomere length among the birds that have passed their prime age of reproduction. These results suggest that physiological and chronological ages may be largely uncoupled in our study system. Furthermore, our findings do not support a hypothesis about the presence of a common physiological factor (e.g., such as oxidative stress) that would cause covariation between two independent markers of aging.

  19. Trophic structure in a seabird host-parasite food web: insights from stable isotope analyses.

    Directory of Open Access Journals (Sweden)

    Elena Gómez-Díaz

    Full Text Available Ecological studies on food webs rarely include parasites, partly due to the complexity and dimensionality of host-parasite interaction networks. Multiple co-occurring parasites can show different feeding strategies and thus lead to complex and cryptic trophic relationships, which are often difficult to disentangle by traditional methods. We analyzed stable isotope ratios of C ((13C/(12C, delta(13C and N ((15N/(14N, delta(15N of host and ectoparasite tissues to investigate trophic structure in 4 co-occurring ectoparasites: three lice and one flea species, on two closely related and spatially segregated seabird hosts (Calonectris shearwaters. delta(13C isotopic signatures confirmed feathers as the main food resource for the three lice species and blood for the flea species. All ectoparasite species showed a significant enrichment in delta(15N relatively to the host tissue consumed (discrimination factors ranged from 2 to 5 per thousand depending on the species. Isotopic differences were consistent across multiple host-ectoparasite locations, despite of some geographic variability in baseline isotopic levels. Our findings illustrate the influence of both ectoparasite and host trophic ecology in the isotopic structuring of the Calonectris ectoparasite community. This study highlights the potential of stable isotope analyses in disentangling the nature and complexity of trophic relationships in symbiotic systems.

  20. Stimulation of gaseous phosphine production from Antarctic seabird guanos and ornithogenic soils

    Institute of Scientific and Technical Information of China (English)

    ZHU Renbin; LIU Yashu; SUN Jianjun; SUN Liguang; GENG Jinju

    2009-01-01

    Matrix-bound phosphine (MBP) is a general term used to indicate non-gaseous reduced phosphorus compounds that are transformed into phosphine gas upon reaction with bases or acids. Antarctic seabird guanos and ornithogenic soils were used as materials to compare the different digestion methods for transforming matrix-bound phosphine into phosphine gas. The results demonstrated that more phosphine gas in most of Antarctic environmental materials was formed of matrix-bound phosphine by caustic digestion than by acidic digestion. The comparative study on different digestion methods also revealed that the fraction of MBP converted to gaseous phosphine during the digestion depended on the temperature. The optimal digestion temperature was close to 70℃ and the optimal digestion time was about 20 min. Acidic conditions were more favorable for the release of matrix-bound phosphine compared to the central[u1] conditions. The proper additional water dilution can increase the production and emission of phosphine from the Antarctic penguin guanos.

  1. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities

    Science.gov (United States)

    Zwolicki, Adrian; Zmudczyńska-Skarbek, Katarzyna; Richard, Pierre; Stempniewicz, Lech

    2016-01-01

    We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic) that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris) from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina). Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale. PMID:27149113

  2. Endocrine correlates of parental care in an Antarctic winter breeding seabird, the emperor penguin, Aptenodytes forsteri.

    Science.gov (United States)

    Lormée, H; Jouventin, P; Chastel, O; Mauget, R

    1999-02-01

    Plasma levels of luteinizing hormone (LH) and prolactin associated with parental behavior were measured in the Antarctic winter breeding emperor penguin, Aptenodytes forsteri. Males exclusively incubate the egg while females exclusively brood the nonhomeothermic young; both sexes alternate in rearing the homeothermic young. Birds were sampled on arrival from the sea through egg laying, incubation, and brooding. All parent birds lost their chicks at the end of the brooding period due to harsh weather but sampling continued. In females, LH titers dropped after egg laying but levels were restored when the birds returned from the sea to brood the chicks and were not depressed by high prolactin levels. Plasma prolactin remained low in males captured on arrival and kept until the free-living males finished incubation. In breeders, prolactin secretion increased during the prelaying period when day length decreased. Prolactin levels stayed elevated in males during incubation and in brooding females returning after a 2-month absence at sea. Prolactin values were higher in brooding females than in males ending incubation or returning in late brooding. These levels did not drop after chick loss, and the sexual difference in prolactin values was maintained after breeding failure. In emperor penguins, increased prolactin secretion appears to be triggered around the time of egg laying and continues, driven by an endogenous mechanism, through incubation and brooding until rearing is completed. Prolactin secretion independent of external stimuli may have evolved in pelagic seabirds to maintain parental care despite long absences at sea from the breeding colony.

  3. Evidence of a shift in the cyclicity of Antarctic seabird dynamics linked to climate.

    Science.gov (United States)

    Jenouvrier, Stéphanie; Weimerskirch, Henri; Barbraud, Christophe; Park, Young-Hyang; Cazelles, Bernard

    2005-05-07

    Ecosystems and populations are known to be influenced not only by long-term climatic trends, but also by other short-term climatic modes, such as interannual and decadal-scale variabilities. Because interactions between climatic forcing, biotic and abiotic components of ecosystems are subtle and complex, analysis of long-term series of both biological and physical factors is essential to understanding these interactions. Here, we apply a wavelet analysis simultaneously to long-term datasets on the environment and on the populations and breeding success of three Antarctic seabirds (southern fulmar, snow petrel, emperor penguin) breeding in Terre Adélie, to study the effects of climate fluctuations on Antarctic marine ecosystems. We show that over the past 40 years, populations and demographic parameters of the three species fluctuate with a periodicity of 3-5 years that was also detected in sea-ice extent and the Southern Oscillation Index. Although the major periodicity of these interannual fluctuations is not common to different species and environmental variables, their cyclic characteristics reveal a significant change since 1980. Moreover, sliding-correlation analysis highlighted the relationships between environmental variables and the demography of the three species, with important change of correlation occurring between the end of the 1970s and the beginning of the 1980s. These results suggest that a regime shift has probably occurred during this period, significantly affecting the Antarctic ecosystem, but with contrasted effects on the three species.

  4. Fathers matter: male body mass affects life-history traits in a size-dimorphic seabird.

    Science.gov (United States)

    Cornioley, Tina; Jenouvrier, Stéphanie; Börger, Luca; Weimerskirch, Henri; Ozgul, Arpat

    2017-05-17

    One of the predicted consequences of climate change is a shift in body mass distributions within animal populations. Yet body mass, an important component of the physiological state of an organism, can affect key life-history traits and consequently population dynamics. Over the past decades, the wandering albatross-a pelagic seabird providing bi-parental care with marked sexual size dimorphism-has exhibited an increase in average body mass and breeding success in parallel with experiencing increasing wind speeds. To assess the impact of these changes, we examined how body mass affects five key life-history traits at the individual level: adult survival, breeding probability, breeding success, chick mass and juvenile survival. We found that male mass impacted all traits examined except breeding probability, whereas female mass affected none. Adult male survival increased with increasing mass. Increasing adult male mass increased breeding success and mass of sons but not of daughters. Juvenile male survival increased with their chick mass. These results suggest that a higher investment in sons by fathers can increase their inclusive fitness, which is not the case for daughters. Our study highlights sex-specific differences in the effect of body mass on the life history of a monogamous species with bi-parental care. © 2017 The Authors.

  5. Climatic influence on demographic parameters of a tropical seabird varies with age and sex.

    Science.gov (United States)

    Oro, Daniel; Torres, Roxana; Rodríguez, Cristina; Drummond, Hugh

    2010-04-01

    In marine ecosystems climatic fluctuation and other physical variables greatly influence population dynamics, but differential effects of physical variables on the demographic parameters of the two sexes and different age classes are largely unexplored. We analyzed the effects of climate on the survival and recruitment of both sexes and several age classes of a long-lived tropical seabird, the Blue-footed Booby (Sula nebouxii), using long-term observations on marked individuals. Results demonstrated a complex interaction between yearly fluctuations in climate (both local and global indexes, during both winter and breeding season) and the sex and age of individuals. Youngest birds' survival and recruitment were commonly affected by local climate, whereas oldest birds' parameters tended to be constant and less influenced by environmental variables. These results confirm the theoretical prediction that sex- and age-related variation in life-history demographic traits is greater under poor environmental conditions, and they highlight the importance of including variability in fitness components in demographic and evolutionary models. Males and females showed similar variation in survival but different recruitment patterns, in relation to both age and the spatial scale of climatic influence (local or global). Results indicate different life-history tactics for each sex and different ages, with birds likely trying to maximize their fitness by responding to the environmental contingencies of each year.

  6. Long-term isolation of a highly mobile seabird on the Galapagos

    Science.gov (United States)

    Hailer, Frank; Schreiber, E.A.; Miller, Joshua M.; Levin, Iris I.; Parker, Patricia G.; Chesser, R. Terry; Fleischer, Robert C.

    2011-01-01

    The Galapagos Islands are renowned for their high degree of endemism. Marine taxa inhabiting the archipelago might be expected to be an exception, because of their utilization of pelagic habitats--the dispersal barrier for terrestrial taxa--as foraging grounds. Magnificent frigatebirds (Fregata magnificens) have a highly vagile lifestyle and wide geographical distribution around the South and Central American coasts. Given the potentially high levels of gene flow among populations, the species provides a good test of the effectiveness of the Galapagos ecosystem in isolating populations of highly dispersive marine species. We studied patterns of genetic (mitochondrial DNA, microsatellites and nuclear introns) and morphological variation across the distribution of magnificent frigatebirds. Concordant with predictions from life-history traits, we found signatures of extensive gene flow over most of the range, even across the Isthmus of Panama, which is a major barrier to gene flow in other tropical seabirds. In contrast, individuals from the Galapagos were strongly differentiated from all conspecifics, and have probably been isolated for several hundred thousand years. Our finding is a powerful testimony to the evolutionary uniqueness of the taxa inhabiting the Galapagos archipelago and its associated marine ecosystems.

  7. Effects of human disturbance on cave-nesting seabirds: the case of the storm petrel

    Science.gov (United States)

    Soldatini, Cecilia; Albores-Barajas, Yuri V.; Tagliavia, Marcello; Massa, Bruno; Fusani, Leonida; Canoine, Virginie

    2015-01-01

    Human disturbance is an important stress factor with potentially strong impact on breeding activity in animals. The consequences can be extinction of the breeding population, because disturbed animals might desert their breeding area and find no suitable substitute area. In this study, we investigated the effects of anthropogenic disturbance on a breeding population of Mediterranean storm petrels. Seabirds are increasingly used as bio-indicators for sea environmental parameters, because they are very sensitive to changing conditions. Burrowing or cave-nesting species may be particularly susceptible to human disturbance because their direct contact with humans is usually minimal or absent. First, we compared two different populations (exposed or not exposed to human disturbance) for their individual stress response to a standardized stressor (handling and keeping in a cloth bag). Second, we compared the two sub-colonies for their population-level stress response. Third, we tested experimentally whether sub-colonies of storm petrels exposed to tourism have physiological adaptations to anthropogenic disturbances. Our results indicate that storm petrels may be habituated to moderate disturbance associated with boat traffic close to the colony. PMID:27293726

  8. Hematological and plasma biochemical reference ranges of Alaskan seabirds: Their ecological significance and clinical importance

    Science.gov (United States)

    Newman, S.H.; Piatt, J.F.; White, J.

    1997-01-01

    Blood was analyzed from 151 pelagic marine birds to establish reference ranges for hematological and plasma biochemical parameters from healthy, wild populations of Pacific seabirds. Of the 13 species examined, 9 were from the Family Alcidae (N = 122 individuals) and the remainder (N = 29) from the Families Phalacrocoracidae, Laridae, and Procellariidae. Three of 8 hematological parameters (total white blood cell count, lymphocyte count and eosinophil count) differed significantly among species, as did 9 of 13 plasma biochemical parameters (alkaline phosphatase, aspartate aminotransferase, creatine kinase, cholesterol, glucose, lactate dehydrogenase, total bilirubin, total protein and field total protein). There were no differences among species for packed cell volume, buffy coat, cell counts of heterophils, monoqtes and basophils, or for concentrations of alanine aminotransferase, triglycerides, uric acid and calcium. Plasma calcium concentration, triglyceride levels and field total protein varied significantly between sexes, with females having higher mean concentrations of all 3 parameters. However, no significant relationships between measures of breeding condition (brood patch size, subcutaneous and mesenteric fat deposits, or ovarian follicle size and ovary weight) and calcium or alkaline phosphatase concentrations in female birds could be identified. Alanine aminotransferase and uric acid were the only analytes which did not differ significantly between species or sexes.

  9. Congruent and synchronic patterns in biogeography and speciation among seabirds, pinnipeds, and cestodes.

    Science.gov (United States)

    Hoberg, E P

    1992-08-01

    Congruence in biogeographic patterns among diverse assemblages of taxa indicates uniformity in the historical determinants of biotic distributions. Comparisons of host and parasite phylogenies and the elucidation of distributional area relationships are requisite components of analyses in historical biogeography. Host-parasite associations with broad geographic ranges are often archaic and have been structured largely by coevolutionary processes. In contrast, the origins and radiation of the primary cestode faunas of some seabirds (Alcataenia spp./Alcidae) and pinnipeds (Anophryocephalus spp./Phocidae and Otariidae) are associated with colonization. These young colonizing faunas, in the Holarctic Region, were influenced by a common history during the late Pliocene and Pleistocene epochs. Periodic range contraction, with isolation in refugial centers, and subsequent expansion into postglacial habitats for hosts and parasites coincided with the cyclic pattern of stadials and interstadials. During the past 2-3 million years following colonization, these dramatic climatic fluctuations strongly influenced the continuity of ecological associations in marine habitats and appear to have been the determinants of congruent and synchronic patterns of speciation among these disparate taxa of marine homeotherms and eucestodes.

  10. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities.

    Directory of Open Access Journals (Sweden)

    Adrian Zwolicki

    Full Text Available We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina. Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale.

  11. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities.

    Science.gov (United States)

    Zwolicki, Adrian; Zmudczyńska-Skarbek, Katarzyna; Richard, Pierre; Stempniewicz, Lech

    2016-01-01

    We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic) that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris) from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina). Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale.

  12. Obstacle Avoidance Through Visual Teleoperation

    Directory of Open Access Journals (Sweden)

    Muhammad Usman Keerio

    2009-01-01

    Full Text Available This paper presents a novel controlling approach forHumanoid Robot to work safely in critical situations like badlight environment using Visual Teleoperation. In this regardmodeling environments for Humanoid Teleoperation Systemis developed. Here virtual reality modeling environmentincludes development of virtual Humanoid BHR-2, andvirtual objects like table etc. The main goal of this work is toenhance our visual teleoperation system for BHR-2 in orderto avoid any collision during real time operation. SoftwareMaya is used for modeling and simulations. Maya plug-insin VC++ provides efficient modeling rule, real timeinteraction, and time saving rendering approach in a virtualenvironment. In this paper the validity of proposed scheme isshown by conducting experiments using offline step overtrajectory to avoid obstacle in bad light environment.

  13. Consumer Privacy and Marketing Avoidance

    OpenAIRE

    Il-Horn Hann; Kai-Lung Hui; Sang-Yong Tom Lee; Ivan Png

    2005-01-01

    We introduce consumer avoidance into analytical marketing research. We show that consumer efforts to conceal themselves and to deflect marketing have a crucial impact on sellers¡¯ marketing strategy. Under reasonable conditions, seller marketing is a strategic complement with consumer concealment. Hence, consumer measures to conceal themselves from marketing will increase its cost-effectiveness and lead sellers to market more. Policies that encourage consumers to conceal their identities woul...

  14. The impact of the 1982-1983 El Niño-Southern Oscillation on seabirds in the Galapagos Islands, Ecuador

    Science.gov (United States)

    Valle, Carlos A.; Cruz, Felipe; Cruz, Justine B.; Merlen, Godfrey; Coulter, Malcolm C.

    1987-12-01

    October 1982 through July 1983, the Galapagos Islands experienced the strongest El Niño-Southern Oscillation (ENSO) event yet recorded, with heavy rains and a warm, unproductive ocean. During this period most seabirds did not breed, and many left the archipelago altogether. Dark-rumped petrels which did breed during the event demonstrated low growth rate of chicks. Censuses and observations demonstrated substantial population decreases of other seabirds during the ENSO. Magnificent frigate birds suffered decreased nesting success, while blue-footed boobies abandoned all nesting attempts. Total censuses of Galapagos penguins and flightless cormorants taken before and after the ENSO demonstrated declines of 77% and 49%, respectively. We discuss the seabird population declines during ENSO and their subsequent recovery.

  15. Surveys of the distribution of seabirds found in the vicinity of proposed geothermal project subzones in the District of Puna, Hawaii. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, M.; Ritchotte, G.; Viggiano, A.; Dwyer, J.; Nielsen, B.; Jacobi, J.D. [Fish and Wildlife Service, Hawaii National Park, HI (United States). Hawaii Research Station

    1994-08-01

    In 1993, the US Fish and Wildlife Service (USFWS) entered into an interagency agreement with the Department of Energy (DOE) to conduct specific biological surveys to identify potential impacts of the proposed geothermal development on the natural resources of the East Rift Zone. This report presents information from published literature information and new field data on seabird populations on the island of Hawaii. These data are analyzed with regard to potential impacts of geothermal development on seabird populations in this area. Fifteen species of seabirds, waterbirds, and shorebirds are documented or suspected of being found using habitats within or immediately adjacent to the three geothermal subzones located in the Puna district on the island of Hawai`i. Of these species, two are on the federal Endangered Species List, three are on the State of Hawaii Endangered Species List, and all 15 are protected by the federal Migratory Bird Act.

  16. Seabird feathers as monitors of the levels and persistence of heavy metal pollution after the Prestige oil spill

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Rocio, E-mail: rocio@rociomoreno.com [Dept. Biologia Animal (Vertebrats), Facultat de Biologia, Universitat de Barcelona, Avgda. Diagonal 645, 08028 Barcelona (Spain); Jover, Lluis, E-mail: lluis_jover@ub.edu [Dept. Salut Publica, Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036 Barcelona (Spain); Diez, Carmen, E-mail: karminha13@gmail.com [Dept. Ecoloxia e Bioloxia Animal, Facultade de Ciencias, Universidade de Vigo, 36310 Vigo, Galicia (Spain); Sanpera, Carola, E-mail: csanpera@ub.edu [Dept. Biologia Animal (Vertebrats), Facultat de Biologia, Universitat de Barcelona, Avgda. Diagonal 645, 08028 Barcelona (Spain)

    2011-10-15

    We measured heavy metal concentrations in yellow-legged gulls (n = 196) and European shags (n = 189) in order to assess the temporal pattern of contaminant exposure following the Prestige oil spill in November 2002. We analysed Pb, Cu, Zn, Cr, Ni and V levels in chick feathers sampled at four colonies during seven post-spill years (2003-2009), and compared results with pre-spill levels obtained from feathers of juvenile shag corpses (grown in spring/summer 2002). Following the Prestige wreck, Cu (4.3-10 {mu}g g{sup -1}) and Pb concentrations (1.0-1.4 {mu}g g{sup -1}) were, respectively, between two and five times higher than pre-spill levels (1.5-3.6 and 0.1-0.4 {mu}g g{sup -1}), but returned to previous background concentrations after three years. Our study highlights the suitability of chick feathers of seabirds for assessing the impact of oil spills on heavy metal contamination, and provides the best evidence to date on the persistence of oil pollution after the Prestige incident. - Highlights: > Seabirds as sentinel species of levels and persistence of heavy metal pollution after oil spills. > Pb, Cu, Zn, Cr, Ni, V in chick feathers of Phalacrocorax aristotelis and Larus michahellis. > Chronic oil pollution in the marine food web for at least three years after the Prestige oil spill. - Monitoring heavy metal in seabird feathers indicated chronic oil pollution in the marine food web for at least three years after the Prestige oil spill.

  17. Combination of at-sea activity, geolocation and feather stable isotopes documents where and when seabirds moult

    Directory of Open Access Journals (Sweden)

    Yves eCherel

    2016-02-01

    Full Text Available Key facets of the foraging ecology of seabirds during the inter-breeding period still remain poorly understood because of the difficulty of studying them at sea, including during the energy-demanding moulting stage. Here, the extent to which three sympatric petrels (Antarctic and thin-billed prions, and blue petrel from the subantarctic Kerguelen Islands modify their foraging ecology during moult was investigated using a combination of complementary tools, namely miniaturized saltwater immersion geolocators (GLS and the isotopic method. Firstly, moulting behaviour was first characterized in the blue petrel, a reference species that is known to renew its plumage in autumn. GLS and feather stable isotopes (13C as a proxy of the birds’ foraging habitat indicated that the post-breeding moult of blue petrel occurred in Antarctic waters. Importantly, activity recorders showed that moult was marked by a strong peak in time spent daily sitting on water, which thereafter declined to lower values during the remaining winter months. Secondly, the peak in time spent sitting on water was used as a proxy to characterize the contrasted moult strategies of the two prion species. As blue petrels demonstrated, thin-billed prions moulted during the post-breeding period in cold Antarctic waters where they fed primarily on low trophic level prey, most likely Antarctic krill (15N as a proxy of the birds’ diet. By contrast, Antarctic prions presented an unexpected pre-breeding moult of longer duration that took place further north, in warm subtropical waters. Interestingly, the two Antarctic moulting species, the blue petrel and thin-billed prion, renewed their plumage at the same time and within the same oceanic zone that is likely to be a previously undescribed hot spot of seabird diversity during the Austral autumn. The study contributes to a growing body of evidence that closely-related species exhibit various foraging strategies allowing ecological

  18. Sources of organochlorine contaminants and mercury in seabirds from the Aleutian archipelago of Alaska: Inferences from spatial and trophic variation

    Science.gov (United States)

    Ricca, Mark A.; Miles, A. Keith; Anthony, Robert G.

    2008-01-01

    Persistent organochlorine compounds and mercury (Hg) have been detected in numerous coastal organisms of the Aleutian archipelago of Alaska, yet sources of these contaminants are unclear. We collected glaucous-winged gulls, northern fulmars, and tufted puffins along a natural longitudinal gradient across the western and central Aleutian Islands (Buldir, Kiska, Amchitka, Adak), and an additional 8 seabird species representing different foraging and migratory guilds from Buldir Island to evaluate: 1) point source input from former military installations, 2) westward increases in contaminant concentrations suggestive of distant source input, and 3) effects of trophic status (δ15N) and carbon source (δ13C) on contaminant accumulation. Concentrations of Σ polychlorinated biphenyls (PCBs) and most chlorinated pesticides in glaucous-winged gulls consistently exhibited a ‘U’-shaped pattern of high levels at Buldir and the east side of Adak and low levels at Kiska and Amchitka. In contrast, concentrations of Σ PCBs and chlorinated pesticides in northern fulmars and tufted puffins did not differ among islands. Hg concentrations increased westward in glaucous-winged gulls and were highest in northern fulmars from Buldir. Among species collected only at Buldir, Hg was notably elevated in pelagic cormorants, and relatively high Σ PCBs were detected in black-legged kittiwakes. Concentrations of Σ PCBs, dichlorodiphenyldichloroethylene (p,p′ DDE), and Hg were positively correlated with δ15N across all seabird species, indicating biomagnification across trophic levels. The east side of Adak Island (a former military installation) was a likely point source of Σ PCBs and p,p′ DDE, particularly in glaucous-winged gulls. In contrast, elevated levels of these contaminants and Hg, along with PCB congener and chlorinated pesticide compositional patterns detected at Buldir Island indicated exposure from distant sources influenced by a combination of atmospheric

  19. Long-term study of at-sea distribution of seabirds and marine mammals in the Scotia Sea, Antarctica

    Institute of Scientific and Technical Information of China (English)

    Jos Luis Orgeira; Mariela del Carmen Alderete; Yohana Gisell Jimnez; Juan Cruz Gonzlez

    2015-01-01

    The Scotia Sea is one of the most biologically rich regions of Antarctica, and it hosts a large community of upper trophic-level predators. Long-term at-sea monitoring provides valuable information on the Antarctic marine ecosystem and relationships among top predators. This paper presents the results of at-sea monitoring of seabirds and cetaceans over five consecutive summer seasons (2010—2014) in the Scotia Sea, Antarctica. A total of 11 656 lfying birds belonging to 24 species were recorded in 884 ten-minute counts. Six Procellariiformes species were abundant: Black-browed Albatross, Cape Petrel, Southern Fulmar, Antarctic Prion, Wilson’s Storm-petrel, and Black-bellied Storm-petrel. Only three of these species accounted for 82%of the total abundance:Antarctic Prion (40%), Southern Fulmar (22%), and Cape Petrel (20%). A total of 678 baleen whales belonging to ifve species were recorded along a sampling effort of 2 351 nautical miles:Humpback, Sei, Southern Right, Fin, and Minke whales, which had different abundances during the study. The Fin Whale had the highest mean encounter rate for the 5 years (0.29 whales per nautical mile), followed by the Humpback Whale (0.09 whales per nautical mile). Annual dissimilarity in abundance of both seabirds and cetaceans occurred in conjunction with changes in the sea surface temperature and ice cover, showing the dependence of top predators on environmental changes. The largest aggregations of all top predators (seabirds and cetaceans) were recorded in two regions, west and south of the South Orkney Islands, suggesting important prey availability (especially krill) in those areas.

  20. Learning to Avoid Risky Actions

    OpenAIRE

    Malfaz, María; Miguel A. Salichs

    2011-01-01

    When a reinforcement learning agent executes actions that can cause frequent damage to itself, it can learn, by using Q-learning, that these actions must not be executed again. However, there are other actions that do not cause damage frequently but only once in a while, for example, risky actions such as parachuting. These actions may imply punishment to the agent and, depending on its personality, it would be better to avoid them. Nevertheless, using the standard Q-learning algorithm, the a...

  1. Jam avoidance with autonomous systems

    CERN Document Server

    Tordeux, Antoine

    2016-01-01

    Many car-following models are developed for jam avoidance in highways. Two mechanisms are used to improve the stability: feedback control with autonomous models and increasing of the interaction within cooperative ones. In this paper, we compare the linear autonomous and collective optimal velocity (OV) models. We observe that the stability is significantly increased by adding predecessors in interaction with collective models. Yet autonomous and collective approaches are close when the speed difference term is taking into account. Within the linear OV models tested, the autonomous models including speed difference are sufficient to maximise the stability.

  2. The Relation between Anxiety Disorder and Experiential Avoidance in Inpatient Adolescents

    Science.gov (United States)

    Venta, Amanda; Sharp, Carla; Hart, John

    2012-01-01

    The current study aimed to examine the relation between experiential avoidance and anxiety disorders, as well as the usefulness of the Avoidance and Fusion Questionnaire for Youth (AFQ-Y; Greco, Lambert, & Baer, 2008) in detecting anxiety disorder in a sample of adolescent inpatients. First, the relation between experiential avoidance and anxiety…

  3. Population dynamics in a long-lived seabird: I. Impact of breeding activity on survival and breeding probability in unbanded king penguins.

    Science.gov (United States)

    Le Bohec, Céline; Gauthier-Clerc, Michel; Grémillet, David; Pradel, Roger; Béchet, Arnaud; Gendner, Jean-Paul; Le Maho, Yvon

    2007-11-01

    Understanding the trade-off between current reproductive effort, future survival and future breeding attempts is crucial for demographic analyses and life history studies. We investigated this trade-off in a population of king penguins (Aptenodytes patagonicus) marked individually with transponders using multistate capture-recapture models. This colonial seabird species has a low annual proportion of non-breeders (13%), despite a breeding cycle which lasts over 1 year. To draw inferences about the consequences of non-breeding, we tested for an effect of reproductive activity on survival and on the probability of subsequent breeding. We found that birds non-breeding in year t show the same survival rate as breeders (two-states analysis: breeding and non-breeding). However, breeders had a lower probability of breeding again the following year. This negative phenotypic correlation suggests the existence of reproductive costs affecting future breeding probability, but it might also be strengthened by late arrival for courtship in year t. A three-state analysis including breeding success revealed that failed breeders in year t have a lower probability to reproduce successfully in year t + 1 than non-breeders in year t, providing some evidence for the existence of reproductive costs. Moreover, successful breeders showed higher survival probability. This positive phenotypic correlation between current reproduction and subsequent survival supports the hypothesis of an heterogeneity in individual quality. Males breeding in year t had a lower probability to breed again in year t + 1 than females, suggesting higher reproductive costs for this sex. Such additional costs might be due to higher male parental investment in the final phase of chick-rearing, which also delays the arrival of males in year t + 1, and decreases their breeding probability. Our study is the first to explore the breeding biology and the demography of penguins without the disturbance of flipper-bands.

  4. Spatial heterogeneity as a genetic mixing mechanism in highly philopatric colonial seabirds.

    Science.gov (United States)

    Cristofari, Robin; Trucchi, Emiliano; Whittington, Jason D; Vigetta, Stéphanie; Gachot-Neveu, Hélène; Stenseth, Nils Christian; Le Maho, Yvon; Le Bohec, Céline

    2015-01-01

    How genetic diversity is maintained in philopatric colonial systems remains unclear, and understanding the dynamic balance of philopatry and dispersal at all spatial scales is essential to the study of the evolution of coloniality. In the King penguin, Aptenodytes patagonicus, return rates of post-fledging chicks to their natal sub-colony are remarkably high. Empirical studies have shown that adults return year after year to their previous breeding territories within a radius of a few meters. Yet, little reliable data are available on intra- and inter-colonial dispersal in this species. Here, we present the first fine-scale study of the genetic structure in a king penguin colony in the Crozet Archipelago. Samples were collected from individual chicks and analysed at 8 microsatellite loci. Precise geolocation data of hatching sites and selective pressures associated with habitat features were recorded for all sampling locations. We found that despite strong natal and breeding site fidelity, king penguins retain a high degree of panmixia and genetic diversity. Yet, genetic structure appears markedly heterogeneous across the colony, with higher-than-expected inbreeding levels, and local inbreeding and relatedness hotspots that overlap predicted higher-quality nesting locations. This points towards heterogeneous population structure at the sub-colony level, in which fine-scale environmental features drive local philopatric behaviour, while lower-quality patches may act as genetic mixing mechanisms at the colony level. These findings show how a lack of global genetic structuring can emerge from small-scale heterogeneity in ecological parameters, as opposed to the classical model of homogeneous dispersal. Our results also emphasize the importance of sampling design for estimation of population parameters in colonial seabirds, as at high spatial resolution, basic genetic features are shown to be location-dependent. Finally, this study stresses the importance of

  5. Spatial heterogeneity as a genetic mixing mechanism in highly philopatric colonial seabirds.

    Directory of Open Access Journals (Sweden)

    Robin Cristofari

    Full Text Available How genetic diversity is maintained in philopatric colonial systems remains unclear, and understanding the dynamic balance of philopatry and dispersal at all spatial scales is essential to the study of the evolution of coloniality. In the King penguin, Aptenodytes patagonicus, return rates of post-fledging chicks to their natal sub-colony are remarkably high. Empirical studies have shown that adults return year after year to their previous breeding territories within a radius of a few meters. Yet, little reliable data are available on intra- and inter-colonial dispersal in this species. Here, we present the first fine-scale study of the genetic structure in a king penguin colony in the Crozet Archipelago. Samples were collected from individual chicks and analysed at 8 microsatellite loci. Precise geolocation data of hatching sites and selective pressures associated with habitat features were recorded for all sampling locations. We found that despite strong natal and breeding site fidelity, king penguins retain a high degree of panmixia and genetic diversity. Yet, genetic structure appears markedly heterogeneous across the colony, with higher-than-expected inbreeding levels, and local inbreeding and relatedness hotspots that overlap predicted higher-quality nesting locations. This points towards heterogeneous population structure at the sub-colony level, in which fine-scale environmental features drive local philopatric behaviour, while lower-quality patches may act as genetic mixing mechanisms at the colony level. These findings show how a lack of global genetic structuring can emerge from small-scale heterogeneity in ecological parameters, as opposed to the classical model of homogeneous dispersal. Our results also emphasize the importance of sampling design for estimation of population parameters in colonial seabirds, as at high spatial resolution, basic genetic features are shown to be location-dependent. Finally, this study stresses the

  6. Variance in prey abundance influences time budgets of breeding seabirds: Evidence from pigeon guillemots Cepphus columba

    Science.gov (United States)

    Litzow, Michael A.; Piatt, J.F.

    2003-01-01

    We use data on pigeon guillemots Cepphus columba to test the hypothesis that discretionary time in breeding seabirds is correlated with variance in prey abundance. We measured the amount of time that guillemots spent at the colony before delivering fish to chicks ("resting time") in relation to fish abundance as measured by beach seines and bottom trawls. Radio telemetry showed that resting time was inversely correlated with time spent diving for fish during foraging trips (r = -0.95). Pigeon guillemots fed their chicks either Pacific sand lance Ammodytes hexapterus, a schooling midwater fish, which exhibited high interannual variance in abundance (CV = 181%), or a variety of non-schooling demersal fishes, which were less variable in abundance (average CV = 111%). Average resting times were 46% higher at colonies where schooling prey dominated the diet. Individuals at these colonies reduced resting times 32% during years of low food abundance, but did not reduce meal delivery rates. In contrast, individuals feeding on non-schooling fishes did not reduce resting times during low food years, but did reduce meal delivery rates by 27%. Interannual variance in resting times was greater for the schooling group than for the non-schooling group. We conclude from these differences that time allocation in pigeon guillemots is more flexible when variable schooling prey dominate diets. Resting times were also 27% lower for individuals feeding two-chick rather than one-chick broods. The combined effects of diet and brood size on adult time budgets may help to explain higher rates of brood reduction for pigeon guillemot chicks fed non-schooling fishes.

  7. Stress hormones suggest opposite trends of food availability for planktivorous and piscivorous seabirds in 2 years

    Science.gov (United States)

    Benowitz-Fredericks, Z. Morgan; Shultz, Michael T.; Kitaysky, Alexander S.

    2008-08-01

    Apex predators can provide valuable information about effects of climate variability on trophodynamics in the Bering Sea. We used corticosterone (the primary avian stress hormone, "CORT") as a proxy of changes in prey availability for planktivorous and piscivorous seabirds. CORT secretion reflects energy balance in breeding individuals and can be used to monitor changes in the marine environment that alter food availability. We tested whether CORT in planktivorous least auklets ( Aethia pusilla) and piscivorous thick-billed murres ( Uria lomvia) on two Pribilof Islands differed spatially or temporally in 2003 and 2004. During June-September of each year, we sampled birds breeding on St. Paul and St. George Islands. We found that seasonal dynamics of CORT varied between years. Although the seasonal dynamics were similar between islands in a year, in 2004 there were inter-island differences in CORT levels for both species. In 2003, CORT in murres was low throughout the season, suggesting that their prey availability (primarily forage fishes) was consistently good. In 2004, CORT levels suggested that overall food availability was poor for murres and declined as the season progressed. For auklets, inter-annual variability was associated with contrasting intra-seasonal patterns in the availability of zooplankton prey (primarily Neocalanus spp.). In 2003, high early-season (June) CORT indicated that auklets were food-limited, but CORT decreased in July, suggesting that the availability of zooplankton improved as the season progressed. In 2004, CORT was low early in the season (June), but an abrupt increase late in the season (July) suggests that food became scarce. Our data indicate that environmental differences between 2003 and 2004 affected prey availability for planktivorous and piscivorous alcids in opposite ways. These results suggest that in the shelf regions of the Bering Sea, the populations of apex predators feeding on zooplankton may be affected by

  8. Molecular evidence for gender differences in the migratory behaviour of a small seabird.

    Directory of Open Access Journals (Sweden)

    Renata J Medeiros

    Full Text Available Molecular sexing revealed an unexpectedly strong female bias in the sex ratio of pre-breeding European Storm Petrels (Hydrobates pelagicus, attracted to playback of conspecific calls during their northwards migration past SW Europe. This bias was consistent across seven years, ranging from 80.8% to 89.7% female (mean annual sex ratio ± SD = 85.5% female ±4.1%. The sex ratio did not differ significantly from unity (i.e., 50% female among (i Storm Petrel chicks at a breeding colony in NW France, (ii adults found dead on beaches in Southern Portugal, (iii breeding birds attending nest burrows in the UK, captured by hand, and (iv adults captured near a breeding colony in the UK using copies of the same sound recordings as used in Southern Europe, indicating that females are not inherently more strongly attracted to playback calls than males. A morphological discriminant function analysis failed to provide a good separation of the sexes, showing the importance of molecular sexing for this species. We found no sex difference in the seasonal or nocturnal timing of migration past Southern Europe, but there was a significant tendency for birds to be caught in sex-specific aggregations. The preponderance of females captured in Southern Europe suggests that the sexes may differ in migration route or in their colony-prospecting behaviour during migration, at sites far away from their natal colonies. Such differences in migration behaviour between males and females are poorly understood but have implications for the vulnerability of seabirds to pollution and environmental change at sea during the non-breeding season.

  9. Mercury, selenium, cadmium and organochlorines in eggs of three Hawaiian seabird species

    Science.gov (United States)

    Ohlendorf, H.M.; Harrison, C.S.

    1986-01-01

    Eggs of three representative species of seabirds (wedge-tailed shearwater Puffinus pacificus; red-footed booby Sula sula; and sooty tern Sterna fuscata) were collected in 1980 to determined differences in heavy metal, Se, and organochlorine residues among species nesting in the Hawaiian Archipelago and among the four nesting sites sampled (Oahu, French Frigate Shoals, Laysan, and Midway). Hg and Se were present in all eggs analysed, but Cd was not detected. Hg was usually highest in booby eggs, and there was a southeast-to-northeast trend toward higher concetrations in this species; booby eggs from Midway contained the highest mean concentration of Hg (0?36 :g g-1, wet weight). Se consistently occurred at lowest concentrations in booby eggs. When Se and Hg concentrations were expressed as nanomoles per gram, Se constituted 94?96% of the combined total at each location for shearwater and tern eggs. In booby eggs, the proportion as Se declined significantly (' = 0?05) from Oahu (93?4%) westward to Midway (85?9%). Although DDT occurred in most of the shearwater eggs from each site, it was not found in booby or tern eggs. DDE occured in all eggs, but mean concentrations did not exceed 0?6 :g g-1. DDE concentrations were higher in eggs from the two south-eastern nesting sites and were consistently highest in shearwater eggs. PCBs were found in most of the shearwater and booby eggs, but were not detected in tern eggs. Other organochlorines usually occurred more frequently in eggs of shearwaters than in other species. The only exception were '-HCH and HCB, which occurred more frequently in booby eggs. Kepone, heptachlor epoxide, chlordane compounds, and toxaphene were not detected. Differences in residue concentrations seem to reflect differences in diets and seasonal movements of the birds, and perhaps other factors such as atmospheric and oceanic transport of chemicals and physiological differences among the species.

  10. Tracking through life stages: adult, immature and juvenile autumn migration in a long-lived seabird.

    Directory of Open Access Journals (Sweden)

    Clara Péron

    Full Text Available Seasonal long-distance migration is likely to be experienced in a contrasted manner by juvenile, immature and adult birds, leading to variations in migratory routes, timing and behaviour. We provide the first analysis of late summer movements and autumn migration in these three life stages, which were tracked concurrently using satellite tags, geolocators or GPS recorders in a long-ranging migratory seabird, the Scopoli's shearwater (formerly named Cory's shearwater, Calonectrisdiomedea breeding on two French Mediterranean islands. During the late breeding season, immatures foraged around their colony like breeding adults, but they were the only group showing potential prospecting movements around non-natal colonies. Global migration routes were broadly comparable between the two populations and the three life stages, with all individuals heading towards the Atlantic Ocean through the strait of Gibraltar and travelling along the West African coast, up to 8000 km from their colony. However, detailed comparison of timing, trajectory and oceanographic conditions experienced by the birds revealed remarkable age-related differences. Compared to adults and immatures, juveniles made a longer stop-over in the Balearic Sea (10 days vs 4 days in average, showed lower synchrony in crossing the Gibraltar strait, had more sinuous pathways and covered longer daily distances (240 km.d(-1 vs 170 km.d(-1. Analysis of oceanographic habitats along migratory routes revealed funnelling selection of habitat towards coastal and more productive waters with increasing age. Younger birds may have reduced navigational ability and learn progressively fine-scale migration routes towards the more profitable travelling and wintering areas. Our study demonstrates the importance of tracking long-lived species through the stages, to better understand migratory behavior and assess differential exposure to at-sea threats. Shared distribution between life stages and populations

  11. Tracking through life stages: adult, immature and juvenile autumn migration in a long-lived seabird.

    Science.gov (United States)

    Péron, Clara; Grémillet, David

    2013-01-01

    Seasonal long-distance migration is likely to be experienced in a contrasted manner by juvenile, immature and adult birds, leading to variations in migratory routes, timing and behaviour. We provide the first analysis of late summer movements and autumn migration in these three life stages, which were tracked concurrently using satellite tags, geolocators or GPS recorders in a long-ranging migratory seabird, the Scopoli's shearwater (formerly named Cory's shearwater, Calonectrisdiomedea) breeding on two French Mediterranean islands. During the late breeding season, immatures foraged around their colony like breeding adults, but they were the only group showing potential prospecting movements around non-natal colonies. Global migration routes were broadly comparable between the two populations and the three life stages, with all individuals heading towards the Atlantic Ocean through the strait of Gibraltar and travelling along the West African coast, up to 8000 km from their colony. However, detailed comparison of timing, trajectory and oceanographic conditions experienced by the birds revealed remarkable age-related differences. Compared to adults and immatures, juveniles made a longer stop-over in the Balearic Sea (10 days vs 4 days in average), showed lower synchrony in crossing the Gibraltar strait, had more sinuous pathways and covered longer daily distances (240 km.d(-1) vs 170 km.d(-1)). Analysis of oceanographic habitats along migratory routes revealed funnelling selection of habitat towards coastal and more productive waters with increasing age. Younger birds may have reduced navigational ability and learn progressively fine-scale migration routes towards the more profitable travelling and wintering areas. Our study demonstrates the importance of tracking long-lived species through the stages, to better understand migratory behavior and assess differential exposure to at-sea threats. Shared distribution between life stages and populations make Scopoli

  12. Small-scale dispersal and survival in a long-lived seabird, the wandering albatross.

    Science.gov (United States)

    Gauthier, Gilles; Milot, Emmanuel; Weimerskirch, Henri

    2010-07-01

    1. Dispersal is a fundamental but still poorly known process in population dynamics and several hypotheses have been proposed to explain its patterns. We studied natal and breeding dispersal and survival in a long-lived seabird, the wandering albatross (Diomedea exulans L.), and examined several hypotheses concerning dispersal patterns in birds. 2. We applied multi-state capture-recapture models to a 36-year data set (1969-2004) collected at three albatross colonies on Ile de Possession, Crozet Islands. Because the species has biennial reproduction, we introduced unobservable states in the model to account for the absence of individuals in those years. 3. Adults were highly faithful to their nesting colony but colony fidelity, as well as survival rate, differed slightly among colonies (fidelity ranged from 0.957 to 0.977). Breeding fidelity was highest in the colony where survival was lowest and individuals were not more likely to change colony following a failed breeding attempt than after a successful one. The colony that attracted most dispersers had the lowest density of nesting birds. 4. Philopatry (the probability that young return to breed at a birth site) was generally high but variable among colonies (ranging from 0.70 to 0.92), and survival of young differed little. Philopatry was highest in the largest colony, where the availability of potential mates was presumably greatest. However, among dispersing individuals, the colony that had the lowest density of nesting individuals, not the largest colony, attracted the most recruits. 5. Although size of the colony influenced the decision to stay or to leave in young, density was most influential in the selection of a new colony among both adult and young dispersers. Our results support the hypothesis that philopatry is the strategy favoured by most recruits and that conspecific attraction can explain variation in the level of philopatry among colonies but not settlement patterns among dispersing individuals.

  13. Seasonal Variation in Parental Care Drives Sex-Specific Foraging by a Monomorphic Seabird.

    Science.gov (United States)

    Burke, Chantelle M; Montevecchi, William A; Regular, Paul M

    2015-01-01

    Evidence of sex-specific foraging in monomorphic seabirds is increasing though the underlying mechanisms remain poorly understood. We investigate differential parental care as a mechanism for sex-specific foraging in monomorphic Common Murres (Uria aalge), where the male parent alone provisions the chick after colony departure. Using a combination of geolocation-immersion loggers and stable isotopes, we assess two hypotheses: the reproductive role specialization hypothesis and the energetic constraint hypothesis. We compare the foraging behavior of females (n = 15) and males (n = 9) during bi-parental at the colony, post-fledging male-only parental care and winter when parental care is absent. As predicted by the reproductive role specialization hypothesis, we found evidence of sex-specific foraging during post-fledging only, the stage with the greatest divergence in parental care roles. Single-parenting males spent almost twice as much time diving per day and foraged at lower quality prey patches relative to independent females. This implies a potential energetic constraint for males during the estimated 62.8 ± 8.9 days of offspring dependence at sea. Contrary to the predictions of the energetic constraint hypothesis, we found no evidence of sex-specific foraging during biparental care, suggesting that male parents did not forage for their own benefit before colony departure in anticipation of post-fledging energy constraints. We hypothesize that unpredictable prey conditions at Newfoundland colonies in recent years may limit male parental ability to allocate additional time and energy to self-feeding during biparental care, without compromising chick survival. Our findings support differential parental care as a mechanism for sex-specific foraging in monomorphic murres, and highlight the need to consider ecological context in the interpretation of sex-specific foraging behavior.

  14. Assessing the nutritional stress hypothesis: Relative influence of diet quantity and quality on seabird productivity

    Science.gov (United States)

    Jodice, P.G.R.; Roby, D.D.; Turco, K.R.; Suryan, R.M.; Irons, D.B.; Piatt, J.F.; Shultz, M.T.; Roseneau, D.G.; Kettle, A.B.; Anthony, J.A.

    2006-01-01

    Food availability comprises a complex interaction of factors that integrates abundance, taxonomic composition, accessibility, and quality of the prey base. The relationship between food availability and reproductive performance can be assessed via the nutritional stress (NSH) and junkfood (JFH) hypotheses. With respect to reproductive success, NSH posits that a deficiency in any of the aforementioned metrics can have a deleterious effect on a population via poor reproductive success. JFH, a component of NSH, posits specifically that it is a decline in the quality of food (i.e. energy density and lipid content) that leads to poor reproductive success. We assessed each in relation to reproductive success in a piscivorous seabird, the black-legged kittiwake Rissa tridactyla. We measured productivity, taxonomic composition, frequency, size, and quality of meals delivered to nestlings from 1996 to 1999 at 6 colonies in Alaska, USA, 3 each in Prince William Sound and Lower Cook Inlet. Productivity varied widely among colony-years. Pacific herring Clupea pallasi, sand lance Ammodytes hexapterus, and capelin Mallotus villosus comprised ca. 80% of the diet among colony-years, and each was characterized by relatively high energy density. Diet quality for kittiwakes in this region therefore remained uniformly high during this study. Meal delivery rate and meal size were quite variable among colony-years, however, and best explained the variability in productivity. Parent kittiwakes appeared to select prey that were energy dense and that maximized the biomass provisioned to broods. While these results fail to support JFH, they do provide substantial support for NSH. ?? Inter-Research 2006.

  15. Population divergence and gene flow in an endangered and highly mobile seabird

    Science.gov (United States)

    Welch, A. J.; Fleischer, R. C.; James, H. F.; Wiley, A. E.; Ostrom, P. H.; Adams, J.; Duvall, F.; Holmes, N.; Hu, D.; Penniman, J.; Swindle, K. A.

    2012-01-01

    Seabirds are highly vagile and can disperse up to thousands of kilometers, making it difficult to identify the factors that promote isolation between populations. The endemic Hawaiian petrel (Pterodroma sandwichensis) is one such species. Today it is endangered, and known to breed only on the islands of Hawaii, Maui, Lanai and Kauai. Historical records indicate that a large population formerly bred on Molokai as well, but this population has recently been extirpated. Given the great dispersal potential of these petrels, it remains unclear if populations are genetically distinct and which factors may contribute to isolation between them. We sampled petrels from across their range, including individuals from the presumably extirpated Molokai population. We sequenced 524 bp of mitochondrial DNA, 741 bp from three nuclear introns, and genotyped 18 microsatellite loci in order to examine the patterns of divergence in this species and to investigate the potential underlying mechanisms. Both mitochondrial and nuclear data sets indicated significant genetic differentiation among all modern populations, but no differentiation was found between historic samples from Molokai and modern birds from Lanai. Population-specific nonbreeding distribution and strong natal philopatry may reduce gene flow between populations. However, the lack of population structure between extirpated Molokai birds and modern birds on Lanai indicates that there was substantial gene flow between these populations and that petrels may be able to overcome barriers to dispersal prior to complete extirpation. Hawaiian petrel populations could be considered distinct management units, however, the dwindling population on Hawaii may require translocation to prevent extirpation in the near future.

  16. Seasonal Variation in Parental Care Drives Sex-Specific Foraging by a Monomorphic Seabird.

    Directory of Open Access Journals (Sweden)

    Chantelle M Burke

    Full Text Available Evidence of sex-specific foraging in monomorphic seabirds is increasing though the underlying mechanisms remain poorly understood. We investigate differential parental care as a mechanism for sex-specific foraging in monomorphic Common Murres (Uria aalge, where the male parent alone provisions the chick after colony departure. Using a combination of geolocation-immersion loggers and stable isotopes, we assess two hypotheses: the reproductive role specialization hypothesis and the energetic constraint hypothesis. We compare the foraging behavior of females (n = 15 and males (n = 9 during bi-parental at the colony, post-fledging male-only parental care and winter when parental care is absent. As predicted by the reproductive role specialization hypothesis, we found evidence of sex-specific foraging during post-fledging only, the stage with the greatest divergence in parental care roles. Single-parenting males spent almost twice as much time diving per day and foraged at lower quality prey patches relative to independent females. This implies a potential energetic constraint for males during the estimated 62.8 ± 8.9 days of offspring dependence at sea. Contrary to the predictions of the energetic constraint hypothesis, we found no evidence of sex-specific foraging during biparental care, suggesting that male parents did not forage for their own benefit before colony departure in anticipation of post-fledging energy constraints. We hypothesize that unpredictable prey conditions at Newfoundland colonies in recent years may limit male parental ability to allocate additional time and energy to self-feeding during biparental care, without compromising chick survival. Our findings support differential parental care as a mechanism for sex-specific foraging in monomorphic murres, and highlight the need to consider ecological context in the interpretation of sex-specific foraging behavior.

  17. Scaling of soaring seabirds and implications for flight abilities of giant pterosaurs.

    Directory of Open Access Journals (Sweden)

    Katsufumi Sato

    Full Text Available The flight ability of animals is restricted by the scaling effects imposed by physical and physiological factors. In comparisons of the power available from muscle and the mechanical power required to fly, it is predicted that the margin between the powers should decrease with body size and that flying animals have a maximum body size. However, predicting the absolute value of this upper limit has proven difficult because wing morphology and flight styles varies among species. Albatrosses and petrels have long, narrow, aerodynamically efficient wings and are considered soaring birds. Here, using animal-borne accelerometers, we show that soaring seabirds have two modes of flapping frequencies under natural conditions: vigorous flapping during takeoff and sporadic flapping during cruising flight. In these species, high and low flapping frequencies were found to scale with body mass (mass(-0.30 and mass(-0.18 in a manner similar to the predictions from biomechanical flight models (mass(-1/3 and mass(-1/6. These scaling relationships predicted that the maximum limits on the body size of soaring animals are a body mass of 41 kg and a wingspan of 5.1 m. Albatross-like animals larger than the limit will not be able to flap fast enough to stay aloft under unfavourable wind conditions. Our result therefore casts doubt on the flying ability of large, extinct pterosaurs. The largest extant soarer, the wandering albatross, weighs about 12 kg, which might be a pragmatic limit to maintain a safety margin for sustainable flight and to survive in a variable environment.

  18. Benefits and costs of increased levels of corticosterone in seabird chicks.

    Science.gov (United States)

    Kitaysky, A S; Kitaiskaia, E V; Piatt, J F; Wingfield, J C

    2003-01-01

    Seabird chicks respond to food shortages by increasing corticosterone (cort) secretion, which is probably associated with fitness benefits and costs. To examine this, we experimentally increased levels of circulating cort in captive black-legged kittiwake chicks fed ad libitum. We found that cort-implanted chicks begged more frequently and were more aggressive compared to controls. These behavioral modifications must be beneficial to chicks as they facilitate acquisition of food from the parents and might trigger brood reduction and reduced competition for food. Cort-implanted chicks also increased food intake; however, their growth rates were similar to controls. To examine the costs of chronically increased circulating levels of cort, we removed cort implants and, after a 10-day recovery period, tested cognitive abilities of young kittiwakes. We found that the ability of kittiwakes to associate a visual cue with the presence of food in a choice situation was compromised by the experimental elevation of cort during development. To examine the long-term costs of increased levels of cort, 8 months later we tested the performance of the same individuals in a spatial task requiring them to make a detour around a barrier in order to escape from an enclosure. Individuals treated with cort during development took significantly more time to solve this task compared to controls. The results of this study suggest that the adrenocortical response of a developing bird to environmental stressors is associated with both benefits (increased food intake, foraging behavior, and aggression) and costs (low growth efficiency and compromised cognitive abilities later in life). This provides an evolutionary framework for relating juvenile physiological traits to fitness of birds in subsequent life-history stages.

  19. Honey bees selectively avoid difficult choices.

    Science.gov (United States)

    Perry, Clint J; Barron, Andrew B

    2013-11-19

    Human decision-making strategies are strongly influenced by an awareness of certainty or uncertainty (a form of metacognition) to increase the chances of making a right choice. Humans seek more information and defer choosing when they realize they have insufficient information to make an accurate decision, but whether animals are aware of uncertainty is currently highly contentious. To explore this issue, we examined how honey bees (Apis mellifera) responded to a visual discrimination task that varied in difficulty between trials. Free-flying bees were rewarded for a correct choice, punished for an incorrect choice, or could avoid choosing by exiting the trial (opting out). Bees opted out more often on difficult trials, and opting out improved their proportion of successful trials. Bees could also transfer the concept of opting out to a novel task. Our data show that bees selectively avoid difficult tasks they lack the information to solve. This finding has been considered as evidence that nonhuman animals can assess the certainty of a predicted outcome, and bees' performance was comparable to that of primates in a similar paradigm. We discuss whether these behavioral results prove bees react to uncertainty or whether associative mechanisms can explain such findings. To better frame metacognition as an issue for neurobiological investigation, we propose a neurobiological hypothesis of uncertainty monitoring based on the known circuitry of the honey bee brain.

  20. Shape optimization of self-avoiding curves

    Science.gov (United States)

    Walker, Shawn W.

    2016-04-01

    This paper presents a softened notion of proximity (or self-avoidance) for curves. We then derive a sensitivity result, based on shape differential calculus, for the proximity. This is combined with a gradient-based optimization approach to compute three-dimensional, parameterized curves that minimize the sum of an elastic (bending) energy and a proximity energy that maintains self-avoidance by a penalization technique. Minimizers are computed by a sequential-quadratic-programming (SQP) method where the bending energy and proximity energy are approximated by a finite element method. We then apply this method to two problems. First, we simulate adsorbed polymer strands that are constrained to be bound to a surface and be (locally) inextensible. This is a basic model of semi-flexible polymers adsorbed onto a surface (a current topic in material science). Several examples of minimizing curve shapes on a variety of surfaces are shown. An advantage of the method is that it can be much faster than using molecular dynamics for simulating polymer strands on surfaces. Second, we apply our proximity penalization to the computation of ideal knots. We present a heuristic scheme, utilizing the SQP method above, for minimizing rope-length and apply it in the case of the trefoil knot. Applications of this method could be for generating good initial guesses to a more accurate (but expensive) knot-tightening algorithm.

  1. Does the Organized Sexual Murderer Better Delay and Avoid Detection?

    Science.gov (United States)

    Beauregard, Eric; Martineau, Melissa

    2016-01-01

    According to the organized-disorganized model, organized sexual murderers adopt specific behaviors during the commission of their crimes that contribute to avoiding police detection. The current study examines the effect of sexual murderers' organized behaviors on their ability to both delay and/or avoid police detection. Using a combination of negative binomial and logistic regression analyses on a sample of 350 sexual murder cases, findings showed that although both measures of delaying and avoiding detection are positively correlated, different behavioral patterns were observed. For instance, offenders who moved the victim's body were more likely to avoid detection but the victim's body was likely to be recovered faster. Moreover, victim characteristics have an impact on both measures; however, this effect disappears for the measure of delaying detection once the organized behaviors are introduced. Implications of the findings are discussed.

  2. Autonomous hazard detection and avoidance

    Science.gov (United States)

    Pien, Homer

    1992-01-01

    During GFY 91, Draper Laboratory was awarded a task by NASA-JSC under contract number NAS9-18426 to study and evaluate the potential for achieving safe autonomous landings on Mars using an on-board autonomous hazard detection and avoidance (AHDA) system. This report describes the results of that study. The AHDA task had four objectives: to demonstrate, via a closed-loop simulation, the ability to autonomously select safe landing sites and the ability to maneuver to the selected site; to identify key issues in the development of AHDA systems; to produce strawman designs for AHDA sensors and algorithms; and to perform initial trade studies leading to better understanding of the effect of sensor/terrain/viewing parameters on AHDA algorithm performance. This report summarizes the progress made during the first year, with primary emphasis on describing the tools developed for simulating a closed-loop AHDA landing. Some cursory performance evaluation results are also presented.

  3. On the role of subsecond dopamine release in conditioned avoidance

    Directory of Open Access Journals (Sweden)

    Erik B Oleson

    2013-06-01

    Full Text Available Using shock avoidance procedures to study conditioned behavioral responses has a rich history within the field of experimental psychology. Such experiments led to the formulation of the general concept of negative reinforcement and specific theories attempting to explain escape and avoidance behavior, or why animals choose to either terminate or prevent the presentation of an aversive event. For example, the two-factor theory of avoidance holds that cues preceding an aversive event begin to evoke conditioned fear responses, and these conditioned fear responses reinforce the instrumental avoidance response. Current neuroscientific advances are providing new perspectives into this historical literature. Due to its well-established role in reinforcement processes and behavioral control, the mesolimbic dopamine system presented itself as a logical starting point in the search for neural correlates of avoidance and escape behavior. We recently demonstrated that phasic dopamine release events are inhibited by stimuli associated with aversive events but increased by stimuli preceding the successful avoidance of the aversive event. The latter observation is inconsistent with the second component of the two-factor theory of avoidance and; therefore, led us propose a new theoretical explanation of conditioned avoidance: 1 fear is initially conditioned to the warning signal and dopamine computes this fear association as a decrease in release, 2 the warning signal, now capable of producing a negative emotional state, suppresses dopamine release and behavior, 3 over repeated trials the warning signal becomes associated with safety rather than fear; dopaminergic neurons already compute safety as an increase in release and begin to encode the warning signal as the earliest predictor of safety 4 the warning signal now promotes conditioned avoidance via dopaminergic modulation of the brain’s incentive-motivational circuitry.

  4. The seabird paradox: dispersal, genetic structure and population dynamics in a highly mobile, but philopatric albatross species.

    Science.gov (United States)

    Milot, Emmanuel; Weimerskirch, Henri; Bernatchez, Louis

    2008-04-01

    The philopatric behaviour of albatrosses has intrigued biologists due to the high mobility of these seabirds. It is unknown how albatrosses maintain a system of fragmented populations without frequent dispersal movements, in spite of the long-term temporal heterogeneity in resource distribution at sea. We used both genetic (amplified fragment length polymorphism) and capture-mark-recapture (CMR) data to identify explicitly which among several models of population dynamics best applies to the wandering albatross (Diomedea exulans) and to test for migration-drift equilibrium. We previously documented an extremely low genetic diversity in this species. Here, we show that populations exhibit little genetic differentiation across the species' range (Theta(B) albatross. Yet, our data suggest that several other factors including ongoing gene flow, recurrent long-distance dispersal and source-sink dynamics have contributed to different extent in shaping the genetic signature observed in this species. Our results show that an absence of genetic structuring may in itself reveal little about the true population dynamics in seabirds, but can provide insights into important processes when a comparison with other information, such as demographic data, is possible.

  5. Seabirds indicate changes in the composition of plastic litter in the Atlantic and south-western Indian Oceans.

    Science.gov (United States)

    Ryan, Peter G

    2008-08-01

    I compare plastic ingested by five species of seabirds sampled in the 1980s and again in 1999-2006. The numbers of ingested plastic particles have not changed significantly, but the proportion of virgin pellets has decreased 44-79% in all five species: great shearwater Puffinus gravis, white-chinned petrel Procellaria aequinoctialis, broad-billed prion Pachyptila vittata, white-faced storm petrel Pelagodroma marina and white-bellied storm petrel Fregetta grallaria. The populations sampled range widely in the South Atlantic and western Indian Oceans. The most marked reduction occurred in great shearwaters, where the average number of pellets per bird decreased from 10.5 to 1.6. This species migrates between the South and North Atlantic each year. Similar decreases in virgin pellets have been recorded in short-tailed shearwaters Puffinus tenuirostris in the Pacific Ocean and northern fulmars Fulmarus glacialis in the North Sea. More data are needed on the relationship between plastic loads in seabirds and the density of plastic at sea in their foraging areas, but the consistent decrease in pellets in birds suggests there has been a global change in the composition of small plastic debris at sea over the last two decades.

  6. Facilitated Leaching of Additive-Derived PBDEs from Plastic by Seabirds' Stomach Oil and Accumulation in Tissues.

    Science.gov (United States)

    Tanaka, Kosuke; Takada, Hideshige; Yamashita, Rei; Mizukawa, Kaoruko; Fukuwaka, Masa-Aki; Watanuki, Yutaka

    2015-10-06

    Our previous study suggested the transfer of polybrominated diphenyl ether (PBDE) flame retardants from ingested plastics to seabirds' tissues. To understand how the PBDEs are transferred, we studied leaching from plastics into digestive fluids. We hypothesized that stomach oil, which is present in the digestive tract of birds in the order Procellariiformes, acts as an organic solvent, facilitating the leaching of hydrophobic chemicals. Pieces of plastic compounded with deca-BDE were soaked in several leaching solutions. Trace amounts were leached into distilled water, seawater, and acidic pepsin solution. In contrast, over 20 times as much material was leached into stomach oil, and over 50 times as much into fish oil (a major component of stomach oil). Analysis of abdominal adipose, liver tissue, and ingested plastics from 18 wild seabirds collected from the North Pacific Ocean showed the occurrence of deca-BDE or hexa-BDEs in both the tissues and the ingested plastics in three of the birds, suggesting transfer from the plastic to the tissues. In birds with BDE209 in their tissues, the dominance of BDE207 over other nona-BDE isomers suggested biological debromination at the meta position. Model calculation of PBDE exposure to birds based on the results of the leaching experiments combined with field observations suggested the dominance of plastic-mediated internal exposure to BDE209 over exposure via prey.

  7. Characterizing exposure and potential impacts of contaminants on seabirds nesting at South San Diego Bay Unit of the San Diego National Wildlife Refuge (Salt Works, San Diego Bay)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2005, a two-year USFWS study (1261-1N74) was initiated to characterize contaminant exposure by seabirds that nest in colonies at the South Bay Salt Works, within...

  8. Does by-catch pose a threat for the conservation of seabird populations in the southern Ionian Sea (eastern Mediterranean? A questionnaire based survey of local fisheries

    Directory of Open Access Journals (Sweden)

    G. KARRIS

    2013-09-01

    Full Text Available A significant number of studies worldwide have shown that incidental catches (by-catch of seabirds in fishing gear might pose a considerable risk for the conservation of their populations. Nevertheless reliable data on by-catch rates of seabirds in European marine ecosystems are patchy and need to be improved. This study constitutes a first attempt at the evaluation of by-catch rates in the southern Ionian Sea. Data were obtained by distributing a specific questionnaire to the fishers of Zakynthos Island. 150 professional fishers (representing 90% of the local fishing fleet participated in the research, and were interviewed during July-December 2010. The information collected showed that commercial longline and (to a lesser extent gillnet fishery gears caused incidental catches mostly of Scopoli’s Shearwater and Mediterranean Shag. The temporal analysis of the incidental bird mortality showed that seabirds were more susceptible to be trapped in fishery gears set around sunrise during spring and summer whereas spatial analysis of by-catch data indicated variations in the number of seabirds caught in different fishery areas.

  9. Does by-catch pose a threat for the conservation of seabird populations in the southern Ionian Sea (eastern Mediterranean? A questionnaire based survey of local fisheries

    Directory of Open Access Journals (Sweden)

    G. KARRIS

    2013-07-01

    Full Text Available A significant number of studies worldwide have shown that incidental catches (by-catch of seabirds in fishing gear might pose a considerable risk for the conservation of their populations. Nevertheless reliable data on by-catch rates of seabirds in European marine ecosystems are patchy and need to be improved. This study constitutes a first attempt at the evaluation of by-catch rates in the southern Ionian Sea. Data were obtained by distributing a specific questionnaire to the fishers of Zakynthos Island. 150 professional fishers (representing 90% of the local fishing fleet participated in the research, and were interviewed during July-December 2010. The information collected showed that commercial longline and (to a lesser extent gillnet fishery gears caused incidental catches mostly of Scopoli’s Shearwater and Mediterranean Shag. The temporal analysis of the incidental bird mortality showed that seabirds were more susceptible to be trapped in fishery gears set around sunrise during spring and summer whereas spatial analysis of by-catch data indicated variations in the number of seabirds caught in different fishery areas.

  10. Organochlorines, brominated flame retardants and mercury levels in six seabird species from the Gulf of St. Lawrence (Canada): Relationships with feeding ecology, migration and molt

    Energy Technology Data Exchange (ETDEWEB)

    Lavoie, Raphael A., E-mail: lavoie.raphael@gmail.co [Biology Department, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N 6N5 (Canada); Champoux, Louise [Wildlife and Landscape Science, Science and Technology Branch, Environment Canada, 1 141 Route de l' Eglise, C.P. 10 100, Quebec, QC, G1V 4H5 (Canada); Rail, Jean-Francois [Canadian Wildlife Service, Environmental Stewardship Branch, Environment Canada, 1 141 Route de l' Eglise, C.P. 10 100, Quebec, QC, G1V 4H5 (Canada); Lean, David R.S. [Biology Department, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N 6N5 (Canada)

    2010-06-15

    Concentrations of organochlorines (OCs), brominated flame retardants (BFRs) and mercury (Hg) were measured in eggs of six seabird species breeding in the Gulf of St. Lawrence, Canada. Stable nitrogen (delta{sup 15}N) and carbon (delta{sup 13}C) isotopes were used as ecological tracers to measure trophic level and connectivity with benthos, respectively. Concentrations, patterns as well as ecological tracers varied significantly between species. The sum of polychlorinated biphenyls (SIGMAPCBs) was the most important group measured in all seabird species based on concentration followed generally by the sum of chlorinated pesticides (SIGMACPs), the sum of brominated flame retardants (SIGMABFRs) and finally total Hg (THg). SIGMAPCBs, SIGMACPs and SIGMABFRs increased with trophic level, whereas THg did not. Only SIGMABFRs increased with a higher connectivity with the benthos. Seabird species resident to the Great Lakes-St. Lawrence ecosystem showed higher Hg and BFR levels than migratory species. Molt patterns were used to explain variations of contaminant levels. - Concentrations and patterns of contaminants in seabirds are highly species-specific and related to trophic position, migration and molt.

  11. Allergen avoidance: does it work?

    Science.gov (United States)

    Woodcock, A; Custovic, A

    2000-01-01

    The first recorded example of allergen avoidance in the treatment of allergic disorders dates from the 16th century. The Italian physician Gerolamo Cardano (1501-1576) was invited to Scotland by John Hamilton, Archbishop of St Andrews (and brother of the Regent), to give advice on the treatment of his asthma. Cardano recommended that the Archbishop should get rid of his feather bedding, which was followed by a 'miraculous' remission of otherwise troublesome symptoms. The first controlled attempts to treat asthma by environmental manipulation date to the beginning of 20th century. In 1925, the Leopold brothers treated patients with asthma and other allergic disorders by moving them into a dust free room. Storm van Leeuwen created a 'climate' chamber in The Netherlands in 1927 and demonstrated that asthmatic patients improved when moved from their homes into the chamber. One year later, Dekker observed that measures aimed at reducing the amount of dust in bedrooms had a beneficial effect on asthma symptoms in patients allergic to house dust. Van Leeuwen wrote: 'In our endeavours to find the cause of the attack ... we utilised the known fact that the environment of the asthmatic patient is, as a rule, of primary importance in determining the intensity and frequency of his attacks'. Nowadays, more than ever, it is essential to address the environmental influences on the increasing prevalence of asthma and allergic disorders.

  12. Obstacle avoidance sonar for submarines

    Science.gov (United States)

    Dugas, Albert C.; Webman, Kenneth M.

    2002-05-01

    The Advanced Mine Detection Sonar (AMDS) system was designed to operate in poor environments with high biological and/or shallow-water boundary conditions. It provides increased capability for active detection of volume, close-tethered, and bottom mines, as well as submarine and surface target active/passive detection for ASW and collision avoidance. It also provides bottom topography mapping capability for precise submarine navigation in uncharted littoral waters. It accomplishes this by using advanced processing techniques with extremely narrow beamwidths. The receive array consists of 36 modules arranged in a 15-ft-diameter semicircle at the bottom of the submarine sonar dome to form a chin-mounted array. Each module consists of 40 piezoelectric rubber elements. The modules provide the necessary signal conditioning to the element data prior to signal transmission (uplink) through the hull. The elements are amplified, filtered, converted to digital signals by an A/D converter, and multiplexed prior to uplink to the inboard receiver. Each module also has a downlink over which it receives synchronization and mode/gain control. Uplink and downlink transmission is done using fiberoptic telemetry. AMDS was installed on the USS Asheville. The high-frequency chin array for Virginia class submarines is based on the Asheville design.

  13. Microplastic pollution in the Greenland Sea: Background levels and selective contamination of planktivorous diving seabirds.

    Science.gov (United States)

    Amélineau, F; Bonnet, D; Heitz, O; Mortreux, V; Harding, A M A; Karnovsky, N; Walkusz, W; Fort, J; Grémillet, D

    2016-12-01

    Microplastics have been reported everywhere around the globe. With very limited human activities, the Arctic is distant from major sources of microplastics. However, microplastic ingestions have been found in several Arctic marine predators, confirming their presence in this region. Nonetheless, existing information for this area remains scarce, thus there is an urgent need to quantify the contamination of Arctic marine waters. In this context, we studied microplastic abundance and composition within the zooplankton community off East Greenland. For the same area, we concurrently evaluated microplastic contamination of little auks (Alle alle), an Arctic seabird feeding on zooplankton while diving between 0 and 50 m. The study took place off East Greenland in July 2005 and 2014, under strongly contrasted sea-ice conditions. Among all samples, 97.2% of the debris found were filaments. Despite the remoteness of our study area, microplastic abundances were comparable to those of other oceans, with 0.99 ± 0.62 m(-3) in the presence of sea-ice (2005), and 2.38 ± 1.11 m(-3) in the nearby absence of sea-ice (2014). Microplastic rise between 2005 and 2014 might be linked to an increase in plastic production worldwide or to lower sea-ice extents in 2014, as sea-ice can represent a sink for microplastic particles, which are subsequently released to the water column upon melting. Crucially, all birds had eaten plastic filaments, and they collected high levels of microplastics compared to background levels with 9.99 and 8.99 pieces per chick meal in 2005 and 2014, respectively. Importantly, we also demonstrated that little auks took more often light colored microplastics, rather than darker ones, strongly suggesting an active contamination with birds mistaking microplastics for their natural prey. Overall, our study stresses the great vulnerability of Arctic marine species to microplastic pollution in a warming Arctic, where sea-ice melting is expected to release vast

  14. Foraging segregation of two congeneric diving seabird species breeding on St. George Island, Bering Sea

    Science.gov (United States)

    Kokubun, Nobuo; Yamamoto, Takashi; Sato, Nobuhiko; Watanuki, Yutaka; Will, Alexis; Kitaysky, Alexander S.; Takahashi, Akinori

    2016-04-01

    Subarctic environmental changes are expected to affect the foraging ecology of marine top predators, but the response to such changes may vary among species if they use food resources differently. We examined the characteristics of foraging behavior of two sympatric congeneric diving seabird: common (Uria aalge: hereafter COMUs) and thick-billed (U. lomvia: hereafter TBMUs) murres breeding on St. George Island, located in the seasonal sea-ice region of the Bering Sea. We investigated their foraging trip and flight durations, diel patterns of dive depth, and underwater wing strokes, along with wing morphology and blood stable isotope signatures and stress hormones. Acceleration-temperature-depth loggers were attached to chick-guarding birds, and data were obtained from 7 COMUs and 12 TBMUs. Both species showed similar mean trip duration (13.2 h for COMUs and 10.5 h for TBMUs) and similar diurnal patterns of diving (frequent dives to various depths in the daytime and less frequent dives to shallow depths in the nighttime). During the daytime, the dive depths of COMUs had two peaks in shallow (18.1 m) and deep (74.2 m) depths, while those of TBMUs were 20.2 m and 59.7 m. COMUs showed more frequent wing strokes during the bottom phase of dives (1.90 s-1) than TBMUs (1.66 s-1). Fish occurred more frequently in the bill loads of COMUs (85 %) than those of TBMUs (56 %). The δ15N value of blood was significantly higher in COMUs (14.5 ‰) than in TBMUs (13.1 ‰). The relatively small wing area (0.053 m2) of COMUs compared to TBMUs (0.067 m2) may facilitate their increased agility while foraging and allow them to capture more mobile prey such as larger fishes that inhabit deeper depths. These differences in food resource use may lead to the differential responses of the two murre species to marine environmental changes in the Bering Sea.

  15. Injecting epidemiology into population viability analysis: avian cholera transmission dynamics at an arctic seabird colony.

    Science.gov (United States)

    Iverson, Samuel A; Gilchrist, H Grant; Soos, Catherine; Buttler, Isabel I; Harms, N Jane; Forbes, Mark R

    2016-11-01

    Infectious diseases have the potential to spread rapidly and cause high mortality within populations of immunologically naïve hosts. The recent appearance of avian cholera, a highly virulent disease of birds caused by the bacterium Pasteurella multocida, at remote Arctic seabird colonies is an emerging conservation concern. Determining disease risk to population viability requires a quantitative understanding of transmission potential and the factors that regulate epidemic persistence. Estimates of the basic (R0 ) and real-time (Rt ) reproductive number are critical in this regard - enumerating the number of secondary infections caused by each primary infection in a newly invaded host population and the decline in transmission rate as susceptible individuals are removed via mortality or immunized recovery. Here, we use data collected at a closely monitored common eider (Somateria mollissima) breeding colony located in the Canadian Arctic to examine transmission and host population dynamics. Specifically, we infer epidemic curves from daily mortality observations and use a likelihood-based procedure to estimate changes in the reproductive number over a series of annual outbreaks. These data are interpreted in relation to concurrent changes in host numbers to assess local extinction risk. Consistent with expectations for a novel pathogen invasion, case incidence increased exponentially during the initial wave of exposure (R0  = 2·5; generation time = 6·5 days ± 1·1 SD). Disease conditions gradually abated, but only after several years of smouldering infection (Rt  ≈ 1). In total, 6194 eider deaths were recorded during outbreaks spanning eight consecutive breeding seasons. Breeding pair abundance declined by 56% from the pre-outbreak peak; however, a robust population of >4000 pairs remained intact upon epidemic fade-out. Overall, outbreak patterns were consistent with herd immunity acting as a mitigating factor governing in the extent and duration of

  16. All About PID - Testing and Avoidance in the Field

    Energy Technology Data Exchange (ETDEWEB)

    Hacke, Peter; Johnston, Steve

    2016-09-01

    Potential-induced degradation can cause significant power loss in modules if the appropriate precautions are not taken. In the first part of a new series in PV Tech Power on module failure, Peter Hacke and Steve Johnston assess the current state-of-the-art in detecting, avoiding and mitigating the worst effects of PID.

  17. A longitudinal study of experiential avoidance in emotional disorders

    NARCIS (Netherlands)

    Spinhoven, P.; Drost, J.; Rooij, M. de; Hemert, A.M. van; Penninx, B.W.J.H.

    2014-01-01

    The aim of this study was to examine the degree in which measurements of trait experiential avoidance (EA) are affected by current emotional disorder and whether EA is a causal factor in the course of emotional disorders (anxiety and depressive disorders) and the development of comorbidity among emo

  18. A Longitudinal Study of Experiential Avoidance in Emotional Disorders

    NARCIS (Netherlands)

    Spinhoven, Philip; Drost, Jolijn; de Rooij, Mark; van Hemert, Albert M.; Penninx, Brenda W.

    2014-01-01

    The aim of this study was to examine the degree in which measurements of trait experiential avoidance (EA) are affected by current emotional disorder and whether EA is a causal factor in the course of emotional disorders (anxiety and depressive disorders) and the development of comorbidity among emo

  19. Binge Eating and Weight Control: The Role of Experiential Avoidance

    Science.gov (United States)

    Lillis, Jason; Hayes, Steven C.; Levin, Michael E.

    2011-01-01

    Two thirds of the adults in the United States are overweight or obese. Binge eating is a barrier to treatment adherence and sustained weight loss, and can be seen as a form of experiential avoidance. The current study analyzed the impact of binge eating on weight reduction in a previously published study of a 1-day acceptance and commitment…

  20. Looking after your health. 3. Avoiding varicose veins.

    Science.gov (United States)

    Randall, Sara

    2015-02-01

    This article is to summarise key concepts for the health of the midwife with particular focus on standing for prolonged periods. One of the resultant factors relating to standing postures is the slow but avoidable progression of varicose veins. There is a strong genetic bias to these veins, which can be distressing, but here we will highlight awareness and current research.

  1. Descartes da pesca do camarão sete-barbas como fonte de alimento para aves marinhas Sea-bob-shrimp fishery's by-catch as a feeding source for seabirds

    Directory of Open Access Journals (Sweden)

    Joaquim Olinto Branco

    2001-03-01

    Full Text Available From July 1996 to June 1997, in Armação do Itapocoroy, Penha, Santa Catarina State, Brazil, monthly census were done in three areas of traditional fishery and Itacolomis islands. A total of 10021 seabirds were registered, belonging to eight species, five genus and four families. The average number of seabirds per dragging varied between 80,2 and 113,6. Sterna spp, appeared at first in 43,3% of the released by-catch, followed by Larus dominicanus Lichtenstein, 1823, Fregata magnificens Matheus, 1914, Phalacrocorax brasilianus (Humboldt, 1805 and Sula leucogaster Boddaert, 1783. The average size of the fish consumed by the seabirds oscillated from 8,3 cm (Sterna spp. to 18,5 cm (F. magnificens, with an average time from 6,12 to 7,55 minutes per by-catch released. In general, seabirds use 84,0% of the by-catch fish as a feeding source.

  2. Flight Deck Weather Avoidance Decision Support: Implementation and Evaluation

    Science.gov (United States)

    Wu, Shu-Chieh; Luna, Rocio; Johnson, Walter W.

    2013-01-01

    Weather related disruptions account for seventy percent of the delays in the National Airspace System (NAS). A key component in the weather plan of the Next Generation of Air Transportation System (NextGen) is to assimilate observed weather information and probabilistic forecasts into the decision process of flight crews and air traffic controllers. In this research we explore supporting flight crew weather decision making through the development of a flight deck predicted weather display system that utilizes weather predictions generated by ground-based radar. This system integrates and presents this weather information, together with in-flight trajectory modification tools, within a cockpit display of traffic information (CDTI) prototype. that the CDTI features 2D and perspective 3D visualization models of weather. The weather forecast products that we implemented were the Corridor Integrated Weather System (CIWS) and the Convective Weather Avoidance Model (CWAM), both developed by MIT Lincoln Lab. We evaluated the use of CIWS and CWAM for flight deck weather avoidance in two part-task experiments. Experiment 1 compared pilots' en route weather avoidance performance in four weather information conditions that differed in the type and amount of predicted forecast (CIWS current weather only, CIWS current and historical weather, CIWS current and forecast weather, CIWS current and forecast weather and CWAM predictions). Experiment 2 compared the use of perspective 3D and 21/2D presentations of weather for flight deck weather avoidance. Results showed that pilots could take advantage of longer range predicted weather forecasts in performing en route weather avoidance but more research will be needed to determine what combinations of information are optimal and how best to present them.

  3. Avoidance of influence of negative emotions on students’ health

    Directory of Open Access Journals (Sweden)

    Oleksenko V.M.

    2013-08-01

    Full Text Available Aim of the article is to research the influence of negative emotions on students’ health, which may arise while testing academic achievements of future specialists and elaborate the directions of their avoidance. Material and methods. A range of theoretical and empirical methods is used. The questionnaire of 138 students is realised in Kharkiv National Agrarian University named after V.V. Dockuchayev. The results of the experiment are grounded by Macnamara’s method. Results. The reaction of a young organism to negative emotions during testing is revealed in a form of animosity, disorder of sleep, pain etc. It is determined that the least of harm is done during preliminary testing and much more – during current and concluding ones. Developed and approved directions of avoidance of such negatives are revealed. Conclusions. Testing by the studactive pedagogical technology created by us favours the avoidance of influence of negative emotions on students’ health.

  4. Detection And Avoidance Of Obstacles By Helicopters

    Science.gov (United States)

    Cheng, Victor H. L.; Sridhar, Banavar

    1992-01-01

    Report discusses problems relevant to control subsystems enabling helicopters on nap-of-the-Earth flight paths to detect and avoid obstacles automatically. Indicates similarities between this and obstacle-avoidance problem of industrial mobile robots. Two approaches extend two-dimensional obstacle-avoidance concept to three dimensions. First involves direct search of three-dimensional range-map data for indications of openings between obstacles. Second involves compression of data into two-dimensional map for path search.

  5. Mobile Robot Collision Avoidance in Human Environments

    OpenAIRE

    Lingqi Zeng; Gary M. Bone

    2013-01-01

    Collision avoidance is a fundamental requirement for mobile robots. Avoiding moving obstacles (also termed dynamic obstacles) with unpredictable direction changes, such as humans, is more challenging than avoiding moving obstacles whose motion can be predicted. Precise information on the future moving directions of humans is unobtainable for use in navigation algorithms. Furthermore, humans should be able to pursue their activities unhindered and without worrying about the robots around them....

  6. Good days, bad days: wind as a driver of foraging success in a flightless seabird, the southern rockhopper penguin.

    Directory of Open Access Journals (Sweden)

    Nina Dehnhard

    Full Text Available Due to their restricted foraging range, flightless seabirds are ideal models to study the short-term variability in foraging success in response to environmentally driven food availability. Wind can be a driver of upwelling and food abundance in marine ecosystems such as the Southern Ocean, where wind regime changes due to global warming may have important ecological consequences. Southern rockhopper penguins (Eudyptes chrysocome have undergone a dramatic population decline in the past decades, potentially due to changing environmental conditions. We used a weighbridge system to record daily foraging mass gain (the difference in mean mass of adults leaving the colony in the morning and returning to the colony in the evening of adult penguins during the chick rearing in two breeding seasons. We related the day-to-day variability in foraging mass gain to ocean wind conditions (wind direction and wind speed and tested for a relationship between wind speed and sea surface temperature anomaly (SSTA. Foraging mass gain was highly variable among days, but did not differ between breeding seasons, chick rearing stages (guard and crèche and sexes. It was strongly correlated between males and females, indicating synchronous changes among days. There was a significant interaction of wind direction and wind speed on daily foraging mass gain. Foraging mass gain was highest under moderate to strong winds from westerly directions and under weak winds from easterly directions, while decreasing under stronger easterly winds and storm conditions. Ocean wind speed showed a negative correlation with daily SSTA, suggesting that winds particularly from westerly directions might enhance upwelling and consequently the prey availability in the penguins' foraging areas. Our data emphasize the importance of small-scale, wind-induced patterns in prey availability on foraging success, a widely neglected aspect in seabird foraging studies, which might become more important

  7. Good days, bad days: wind as a driver of foraging success in a flightless seabird, the southern rockhopper penguin.

    Science.gov (United States)

    Dehnhard, Nina; Ludynia, Katrin; Poisbleau, Maud; Demongin, Laurent; Quillfeldt, Petra

    2013-01-01

    Due to their restricted foraging range, flightless seabirds are ideal models to study the short-term variability in foraging success in response to environmentally driven food availability. Wind can be a driver of upwelling and food abundance in marine ecosystems such as the Southern Ocean, where wind regime changes due to global warming may have important ecological consequences. Southern rockhopper penguins (Eudyptes chrysocome) have undergone a dramatic population decline in the past decades, potentially due to changing environmental conditions. We used a weighbridge system to record daily foraging mass gain (the difference in mean mass of adults leaving the colony in the morning and returning to the colony in the evening) of adult penguins during the chick rearing in two breeding seasons. We related the day-to-day variability in foraging mass gain to ocean wind conditions (wind direction and wind speed) and tested for a relationship between wind speed and sea surface temperature anomaly (SSTA). Foraging mass gain was highly variable among days, but did not differ between breeding seasons, chick rearing stages (guard and crèche) and sexes. It was strongly correlated between males and females, indicating synchronous changes among days. There was a significant interaction of wind direction and wind speed on daily foraging mass gain. Foraging mass gain was highest under moderate to strong winds from westerly directions and under weak winds from easterly directions, while decreasing under stronger easterly winds and storm conditions. Ocean wind speed showed a negative correlation with daily SSTA, suggesting that winds particularly from westerly directions might enhance upwelling and consequently the prey availability in the penguins' foraging areas. Our data emphasize the importance of small-scale, wind-induced patterns in prey availability on foraging success, a widely neglected aspect in seabird foraging studies, which might become more important with increasing

  8. Weathering a Dynamic Seascape: Influences of Wind and Rain on a Seabird's Year-Round Activity Budgets.

    Directory of Open Access Journals (Sweden)

    Pierre A Pistorius

    Full Text Available How animals respond to varying environmental conditions is fundamental to ecology and is a question that has gained impetus due to mounting evidence indicating negative effects of global change on biodiversity. Behavioural plasticity is one mechanism that enables individuals and species to deal with environmental changes, yet for many taxa information on behavioural parameters and their capacity to change are lacking or restricted to certain periods within the annual cycle. This is particularly true for seabirds where year-round behavioural information is intrinsically challenging to acquire due to their reliance on the marine environment where they are difficult to study. Using data from over 13,000 foraging trips throughout the annual cycle, acquired using new-generation automated VHF technology, we described sex-specific, year-round activity budgets in Cape gannets. Using these data we investigated the role of weather (wind and rain on foraging activity and time allocated to nest attendance. Foraging activity was clearly influenced by wind speed, wind direction and rainfall during and outside the breeding season. Generally, strong wind conditions throughout the year resulted in relatively short foraging trips. Birds spent longer periods foraging when rainfall was moderate. Nest attendance, which was sex-specific outside of the breeding season, was also influenced by meteorological conditions. Large amounts of rainfall (> 2.5 mm per hour and strong winds (> 13 m s-1 resulted in gannets spending shorter amounts of time at their nests. We discuss these findings in terms of life history strategies and implications for the use of seabirds as bio-indicators.

  9. Organochlorine contaminants in the muscle, liver and brain of seabirds (Larus) from the coastal area of the Southern Baltic.

    Science.gov (United States)

    Falkowska, Lucyna; Reindl, Andrzej R; Grajewska, Agnieszka; Lewandowska, Anita U

    2016-11-01

    The presence of persistent organic pollutants in the environment manifests itself most strongly in the marine trophic chain, where the highest link is comprised of seabirds. At the same time, seabirds are excellent indicators of contamination in their habitat. The present study concentrates on toxic substances: polychlorinated dibenzo-p-dioxin (PCDDs), polychlorinated dibenzofurans (PCDFs) and chlorinated organic pesticides (OCPs) accumulated in the livers, pectoral muscles and brains of dead gulls collected along the Polish coast of the Baltic Sea in the years 2010-12. The highest toxic equivalence was determined in the livers of Larus argentatus (TEQ(birds TEF)-28.3pgg(-1) ww) and Larus marinus (TEQ(birds TEF)-29.9pgg(-1) ww.). However, the toxic equivalence of muscles was lower and amounted to 3.9pgg(-1) ww. and 7.8pgg(-1) ww. respectively for the two species. The lowest toxic equivalence was found in the brains of birds, where only one, the most toxic, 2,3,7,8 TCDD congener was found (TEQ(birds TEF) 0.87pgg(-1) ww). The highest concentration of chloroorganic pesticides was determined in the brains of the birds (total OCP 167.8pgg(-1) ww.), lower concentrations were found in the livers (total OCP 92.1pgg(-1) ww.) and muscles (total OCP 43.1pgg(-1) ww.). With regard to pesticides, the highest proportion in the total OCP content was constituted by DDT and its isomers (liver 81%, muscles 77% and brain 55%). High concentrations of the studied pollutants in the livers of gulls found dead on the coast of the Southern Baltic could have been effected by levels of contamination in the birds' last meals, which resulted in a seven-fold increase of the liver's toxic equivalence and a two-fold increase in OCP concentration in relation to muscles.

  10. Seabird nutrient subsidies benefit non-nitrogen fixing trees and alter species composition in South American coastal dry forests.

    Directory of Open Access Journals (Sweden)

    Gilles Havik

    Full Text Available Marine-derived nutrients can increase primary productivity and change species composition of terrestrial plant communities in coastal and riverine ecosystems. We hypothesized that sea nutrient subsidies have a positive effect on nitrogen assimilation and seedling survival of non-nitrogen fixing species, increasing the relative abundance of non-nitrogen fixing species close to seashore. Moreover, we proposed that herbivores can alter the effects of nutrient supplementation by preferentially feeding on high nutrient plants. We studied the effects of nutrient fertilization by seabird guano on tree recruitment and how these effects can be modulated by herbivorous lizards in the coastal dry forests of northwestern Peru. We combined field studies, experiments and stable isotope analysis to study the response of the two most common tree species in these forests, the nitrogen-fixing Prosopis pallida and the non-nitrogen-fixing Capparis scabrida. We did not find differences in herbivore pressure along the sea-inland gradient. We found that the non-nitrogen fixing C. scabrida assimilates marine-derived nitrogen and is more abundant than P. pallida closer to guano-rich soil. We conclude that the input of marine-derived nitrogen through guano deposited by seabirds feeding in the Pacific Ocean affects the two dominant tree species of the coastal dry forests of northern Peru in contrasting ways. The non-nitrogen fixing species, C. scabrida may benefit from sea nutrient subsidies by incorporating guano-derived nitrogen into its foliar tissues, whereas P. pallida, capable of atmospheric fixation, does not.

  11. Buoyancy under control: underwater locomotor performance in a deep diving seabird suggests respiratory strategies for reducing foraging effort.

    Directory of Open Access Journals (Sweden)

    Timothée R Cook

    Full Text Available BACKGROUND: Because they have air stored in many body compartments, diving seabirds are expected to exhibit efficient behavioural strategies for reducing costs related to buoyancy control. We study the underwater locomotor activity of a deep-diving species from the Cormorant family (Kerguelen shag and report locomotor adjustments to the change of buoyancy with depth. METHODOLOGY/PRINCIPAL FINDINGS: Using accelerometers, we show that during both the descent and ascent phases of dives, shags modelled their acceleration and stroking activity on the natural variation of buoyancy with depth. For example, during the descent phase, birds increased swim speed with depth. But in parallel, and with a decay constant similar to the one in the equation explaining the decrease of buoyancy with depth, they decreased foot-stroke frequency exponentially, a behaviour that enables birds to reduce oxygen consumption. During ascent, birds also reduced locomotor cost by ascending passively. We considered the depth at which they started gliding as a proxy to their depth of neutral buoyancy. This depth increased with maximum dive depth. As an explanation for this, we propose that shags adjust their buoyancy to depth by varying the amount of respiratory air they dive with. CONCLUSIONS/SIGNIFICANCE: Calculations based on known values of stored body oxygen volumes and on deep-diving metabolic rates in avian divers suggest that the variations of volume of respiratory oxygen associated with a respiration mediated buoyancy control only influence aerobic dive duration moderately. Therefore, we propose that an advantage in cormorants--as in other families of diving seabirds--of respiratory air volume adjustment upon diving could be related less to increasing time of submergence, through an increased volume of body oxygen stores, than to reducing the locomotor costs of buoyancy control.

  12. Who Avoids Cancer Information? Examining a Psychological Process Leading to Cancer Information Avoidance.

    Science.gov (United States)

    Chae, Jiyoung

    2016-07-01

    Although cancer information avoidance (CIA) is detrimental to public health, predictors of CIA have not been fully investigated. Based on uncertainty management theory, this study viewed CIA as a response to uncertainty related to the distress associated with cancer information and illustrated the psychological process leading to CIA. Given the current information context, it was hypothesized that cancer information overload (CIO), accompanied by confusion and stress about cancer information, causes CIA. As trait anxiety is a strong predictor of CIO, it was also hypothesized that trait anxiety has an indirect effect on CIA through CIO. Study 1 tested this relationship in a U.S. sample (N = 384); the results showed that CIO was positively associated with CIA and that trait anxiety indirectly influenced CIA through CIO. Whereas Study 1 tested the relationship with cross-sectional data in the general cancer context, Study 2 replicated Study 1 with 3-wave longitudinal data in the context of a specific cancer (i.e., stomach cancer) in South Korea (N = 1,130 at Wave 1, 813 at Wave 2, and 582 at Wave 3). Trait anxiety at Wave 1 predicted CIO at Wave 2, which in turn increased CIA at Wave 3, suggesting that some people are inherently inclined to avoid cancer information due to their trait anxiety, which results in confusion about cancer information.

  13. Approach and avoidance motivation in eating disorders.

    Science.gov (United States)

    Harrison, Amy; Treasure, Janet; Smillie, Luke D

    2011-08-15

    It has been proposed that approach and avoidance processes may be critically involved in the development and maintenance of eating disorders (EDs), including anorexia nervosa (AN) and bulimia nervosa (BN). The Behavioural Inhibition System and Behavioural Activation System Scales (BIS/BAS) and Appetitive Motivation Scale (AMS) questionnaires were administered to 286 participants: 91 healthy controls (HCs), 121 participants with a current ED, either AN (restrictive and binge purge subtypes), or BN and 74 participants recovered from an ED. Individuals with EDs had higher levels of sensitivity to punishment and lower levels of reward reactivity than controls. Individuals in recovery from an ED scored the same as those in the acute group, with the exception of BAS fun seeking, for which they scored significantly higher than those with restricting AN. Discriminant analysis revealed that HCs were maximally separated from those in the acute and recovered ED groups along a dimension reflecting high punishment sensitivity and low reward sensitivity. Classification analysis demonstrated that ED and HC group membership was predicted from reward and punishment sensitivity measures; however recovered participants tended to be misclassified as ED. This study suggests high punishment sensitivity and low reward reactivity/sensitivity might form a personality cluster associated with the risk of developing an ED.

  14. Aerial vehicles collision avoidance using monocular vision

    Science.gov (United States)

    Balashov, Oleg; Muraviev, Vadim; Strotov, Valery

    2016-10-01

    In this paper image-based collision avoidance algorithm that provides detection of nearby aircraft and distance estimation is presented. The approach requires a vision system with a single moving camera and additional information about carrier's speed and orientation from onboard sensors. The main idea is to create a multi-step approach based on a preliminary detection, regions of interest (ROI) selection, contour segmentation, object matching and localization. The proposed algorithm is able to detect small targets but unlike many other approaches is designed to work with large-scale objects as well. To localize aerial vehicle position the system of equations relating object coordinates in space and observed image is solved. The system solution gives the current position and speed of the detected object in space. Using this information distance and time to collision can be estimated. Experimental research on real video sequences and modeled data is performed. Video database contained different types of aerial vehicles: aircrafts, helicopters, and UAVs. The presented algorithm is able to detect aerial vehicles from several kilometers under regular daylight conditions.

  15. Sexual selection as a consequence of pathogen avoidance behaviors

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C. [Argonne National Lab., IL (United States); Logofet, D.O. [Russian Academy of Sciences, Moscow (Russian Federation). Laboratory of Mathematical Ecology

    1997-08-01

    The current theory that sexual selection results from female choice for good genes suffers from several problems. An alternative explanation is proposed. The pathogen avoidance hypothesis argues that the primary function of showy traits is to provide a reliable signal of current disease status so that sick individuals may be avoided during mating. Our studies shown that a significant risk of pathogen transmission occurs during mating and that showy traits are reliable indicators of current disease status. The origin of female choosiness is argued to lie in a general tendency to avoid sick individuals, even in the absence of showy traits. The showy traits are argued to originate as simple exaggerations of normal traits that are indicative of good health (bright feathers; vigorous movement; large size). Thus the origins of both showy traits and female choosiness are not problematic in this theory. A game theory analysis is employed to formalize the theory. Results of the game theory model support the theory. In particular, when the possession of male showy traits does not help reduce disease in the female, then showy traits are unlikely to occur. This case corresponds to the situation in large flocks or herds in which every animal is thoroughly exposed to all group pathogens on average. Such species do not exhibit showy traits. The good genes model does not make this prediction. The pathogen avoidance model can also lead to the evolution of showy traits even when selection is not effective against a given pathogen (e.g., when there is no heritable variation for resistance) but will lead to selection for resistance if such genes are present. Overall, the pathogen avoidance hypothesis provides a complete alternative to the good genes theory.

  16. Avoidable deaths in Greenland 1968-1985

    DEFF Research Database (Denmark)

    Bjerregaard, Peter; Juel, K

    1990-01-01

    The concept of avoidable deaths suggests that certain deaths ought not occur in a given society because it is possible to prevent or treat the disease or condition. A list of avoidable deaths is time and community specific as it reflects the socioeconomic conditions, professional medical capacity...

  17. 47 CFR 74.604 - Interference avoidance.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Interference avoidance. 74.604 Section 74.604 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES EXPERIMENTAL RADIO... Stations § 74.604 Interference avoidance. (a) (b) Where two or more licensees are assigned a common...

  18. Human Hippocampus Arbitrates Approach-Avoidance Conflict

    Science.gov (United States)

    Bach, Dominik R.; Guitart-Masip, Marc; Packard, Pau A.; Miró, Júlia; Falip, Mercè; Fuentemilla, Lluís; Dolan, Raymond J.

    2014-01-01

    Summary Animal models of human anxiety often invoke a conflict between approach and avoidance [1, 2]. In these, a key behavioral assay comprises passive avoidance of potential threat and inhibition, both thought to be controlled by ventral hippocampus [2–6]. Efforts to translate these approaches to clinical contexts [7, 8] are hampered by the fact that it is not known whether humans manifest analogous approach-avoidance dispositions and, if so, whether they share a homologous neurobiological substrate [9]. Here, we developed a paradigm to investigate the role of human hippocampus in arbitrating an approach-avoidance conflict under varying levels of potential threat. Across four experiments, subjects showed analogous behavior by adapting both passive avoidance behavior and behavioral inhibition to threat level. Using functional magnetic resonance imaging (fMRI), we observe that threat level engages the anterior hippocampus, the human homolog of rodent ventral hippocampus [10]. Testing patients with selective hippocampal lesions, we demonstrate a causal role for the hippocampus with patients showing reduced passive avoidance behavior and inhibition across all threat levels. Our data provide the first human assay for approach-avoidance conflict akin to that of animal anxiety models. The findings bridge rodent and human research on passive avoidance and behavioral inhibition and furnish a framework for addressing the neuronal underpinnings of human anxiety disorders, where our data indicate a major role for the hippocampus. PMID:24560572

  19. Seabirds maintain offspring provisioning rate despite fluctuations in prey abundance: A multi-species functional response for guillemots in the North Sea

    DEFF Research Database (Denmark)

    Smout, Sophie; Rindorf, Anna; Wanless, Sarah

    2013-01-01

    . 3. We used annual time-series data on chick provisioning for the common guillemot Uria aalge together with abundance indices for its two main prey (lesser sandeel Ammodytes marinus and sprat Sprattus sprattus) to parameterize a multi-species functional response for parents provisioning chicks...... their parents despite fluctuating prey abundances, conferring some resilience in the face of environmental variation. The parameterized multi-species functional response model can be used to estimate levels of severe prey shortage that compromise provisioning. It also enables us to interpret predator......1. Seabirds that consume more than one prey type may adjust their foraging to maintain provisioning rates for their chicks. How energetically effective are these strategies, and what are the implications for the management of seabirds and their marine habitat? 2. A multi-species functional response...

  20. Seabirds maintain offspring provisioning rate despite fluctuations in prey abundance: A multi-species functional response for guillemots in the North Sea

    DEFF Research Database (Denmark)

    Smout, Sophie; Rindorf, Anna; Wanless, Sarah

    2013-01-01

    1. Seabirds that consume more than one prey type may adjust their foraging to maintain provisioning rates for their chicks. How energetically effective are these strategies, and what are the implications for the management of seabirds and their marine habitat? 2. A multi-species functional response....... 3. We used annual time-series data on chick provisioning for the common guillemot Uria aalge together with abundance indices for its two main prey (lesser sandeel Ammodytes marinus and sprat Sprattus sprattus) to parameterize a multi-species functional response for parents provisioning chicks...... their parents despite fluctuating prey abundances, conferring some resilience in the face of environmental variation. The parameterized multi-species functional response model can be used to estimate levels of severe prey shortage that compromise provisioning. It also enables us to interpret predator...

  1. Rats and seabirds: effects of egg size on predation risk and the potential of conditioned taste aversion as a mitigation method.

    Directory of Open Access Journals (Sweden)

    Lucía Latorre

    Full Text Available Seabirds nesting on islands are threatened by invasive rodents, such as mice and rats, which may attack eggs, chicks and even adults. The low feasibility of rat eradications on many islands makes the development of alternate control plans necessary. We used a combination of field experiments on a Mediterranean island invaded by black rats (Rattusrattus to evaluate (1 the predation risk posed to different-sized seabird eggs and (2, the potential of two deterrent methods (electronic and chemical to reduce its impact. Rats were able to consume eggs of all sizes (12 to 68 g, but survival increased 13 times from the smallest to the largest eggs (which also had more resistant eggshells. Extrapolation to seabird eggs suggests that the smallest species (Hydrobatespelagicus suffer the most severe predation risk, but even the largest (Larusmichahellis could suffer >60% mortality. Nest attack was not reduced by the deterrents. However, chemical deterrence (conditioned taste aversion by lithium chloride slowed the increase in predation rate over time, which resulted in a three-fold increase in egg survival to predation as compared to both control and electronic deterrence. At the end of the experimental period, this effect was confirmed by a treatment swap, which showed that conferred protection remains at least 15 days after cessation of the treatment. Results indicate that small seabird species are likely to suffer severe rates of nest predation by rats and that conditioned taste aversion, but not electronic repellents, may represent a suitable method to protect colonies when eradication or control is not feasible or cost-effective.

  2. A model-based telecoupling analysis for the Patagonian shelf: a new suggested template on how to study global seabirds-fisheries interactions for sustainability

    Science.gov (United States)

    Huettmann, F.; Raya Rey, A.

    2016-12-01

    The Southwest Atlantic Ocean, and the extended Patagonian shelf in particular, presents us with a very complex ecosystem of global relevance for food security and global peace. It is a highly productive area and it maintains a great diversity and abundance of seabird species. Fisheries have been identified as a main stressor for the marine ecosystems and as one of the main causes of seabird population declines. Using the framework of telecoupling - a sophisticated description of natural and socioeconomic interactions over large distances - here we present a fresh holistic look at the dynamic fisheries and (endangered) seabird interactions for the Patagonian shelf. While data are sparse, we employ machine learning-based predictions for a more holistic overview. We found that these waters of the Patagonian Shelf are significantly affected by many nations and outside players. We found that the input, output and spill-over of the Patagonian shelf ecosystem are distributed virtually all over the globe. In addition, we also found `losers' (=nations and their citizens that are left out entirely from this global resource and its governance). Our findings are based on best-available public trade and fish harvest analysis for this region, linked with predictive modeling (machine learning and geographic information systems GIS) to generalize for nine seabird species. We conveniently extend this analysis with a perspective from the financial sector and policy that enables the Patagonian fisheries as international investment and development projects. As increasingly recognized elsewhere, we believe that telecoupling can serve as a new but rather sophisticated study template highlighting wider complexities, bottlenecks and sensitivities for a vastly improved conservation research on oceans and global sustainability questions.

  3. Temporal dynamics of relief in avoidance conditioning and fear extinction: Experimental validation and clinical relevance.

    Science.gov (United States)

    Vervliet, Bram; Lange, Iris; Milad, Mohammed R

    2017-09-01

    The learning principles that guide the acquisition and extinction of avoidance are not fully understood. We developed a novel paradigm to study the temporal dynamics of relief, a putative reinforcer of avoidance, and the recovery of fear and avoidance following extinction. During conditioning, the avoidance action canceled the aversive unconditional stimulus (US), without terminating the predictive conditional stimulus (CS). Relief pleasantness was rated after fixed CS offsets, when US omission occured. Avoidance was effective to one CS, but not to another, to track stimulus-specific avoidance learning. Fear was extinguished under response prevention in a separate context. Recovery tests took place 24 h later, in both contexts and with a monetary cost added to the avoidance action. We found that avoidance gradually became stimulus-specific during conditioning, but hardly recovered during delayed testing. Across all phases, initial omissions of the aversive US triggered relief that gradually declined over consecutive omissions, in line with a theoretical prediction error signal. Participants that scored low on distress tolerance, however, displayed sustained levels of relief over continuous omissions. We propose that such forms of sustained relief may produce over-reinforcement of foregoing avoidance actions and promote the development of pathological avoidance. The current paradigm represents an efficacious tool to study the temporal dynamics of relief across avoidance learning and fear extinction and to characterize relief dysregulations in relation to psychopathology. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Does temporal variation of mercury levels in Arctic seabirds reflect changes in global environmental contamination, or a modification of Arctic marine food web functioning?

    Science.gov (United States)

    Fort, Jérôme; Grémillet, David; Traisnel, Gwendoline; Amélineau, Françoise; Bustamante, Paco

    2016-04-01

    Studying long-term trends of contaminants in Arctic biota is essential to better understand impacts of anthropogenic activities and climate change on the exposure of sensitive species and marine ecosystems. We concurrently measured temporal changes (2006-2014) in mercury (Hg) contamination of little auks (Alle alle; the most abundant Arctic seabird) and in their major zooplankton prey species (Calanoid copepods, Themisto libellula, Gammarus spp.). We found an increasing contamination of the food-chain in East Greenland during summer over the last decade. More specifically, bird contamination (determined by body feather analyses) has increased at a rate of 3.4% per year. Conversely, bird exposure to Hg during winter in the northwest Atlantic (determined by head feather analyses) decreased over the study period (at a rate of 1.5% per year), although winter concentrations remained consistently higher than during summer. By combining mercury levels measured in birds and zooplankton to isotopic analyses, our results demonstrate that inter-annual variations of Hg levels in little auks reflect changes in food-chain contamination, rather than a reorganization of the food web and a modification of seabird trophic ecology. They therefore underline the value of little auks, and Arctic seabirds in general, as bio-indicators of long-term changes in environmental contamination.

  5. Wide range of metallic and organic contaminants in various tissues of the Antarctic prion, a planktonophagous seabird from the Southern Ocean.

    Science.gov (United States)

    Fromant, Aymeric; Carravieri, Alice; Bustamante, Paco; Labadie, Pierre; Budzinski, Hélène; Peluhet, Laurent; Churlaud, Carine; Chastel, Olivier; Cherel, Yves

    2016-02-15

    Trace elements (n=14) and persistent organic pollutants (POPs, n=30) were measured in blood, liver, kidney, muscle and feathers of 10 Antarctic prions (Pachyptila desolata) from Kerguelen Islands, southern Indian Ocean, in order to assess their concentrations, tissue distribution, and inter-tissue and inter-contaminant relationships. Liver, kidney and feathers presented the highest burdens of arsenic, cadmium and mercury, respectively. Concentrations of cadmium, copper, iron, and zinc correlated in liver and muscle, suggesting that uptake and pathways of metabolism and storage were similar for these elements. The major POPs were 4,4'-DDE, mirex, PCB-153 and PCB-138. The concentrations and tissue distribution patterns of environmental contaminants were overall in accordance with previous results in other seabirds. Conversely, some Antarctic prions showed surprisingly high concentrations of BDE-209. This compound has been rarely observed in seabirds before, and its presence in Antarctic prions could be due to the species feeding habits or to the ingestion of plastic debris. Overall, the study shows that relatively lower trophic level seabirds (zooplankton-eaters) breeding in the remote southern Indian Ocean are exposed to a wide range of environmental contaminants, in particular cadmium, selenium and some emerging-POPs, which merits further toxicological investigations.

  6. The Role of Approach and Avoidance Motives for Unemployed Job Search Behavior

    Science.gov (United States)

    van Dam, Karen; Menting, Lotte

    2012-01-01

    The current study investigated the role of approach and avoidance motives for unemployed job search behavior. Two approach motives (employment and PJ-fit) and two avoidance motives (low-expectation and low-interest) were distinguished. Antecedents and consequences of these motives were examined using a sample of 303 unemployed clients of…

  7. USAID IT Reform Cost Savings/Avoidance

    Data.gov (United States)

    US Agency for International Development — The Office of the Chief Information Officer in the Management Bureau of USAID launched initiatives designed for IT cost savings and avoidance. This dataset includes...

  8. Dual Eligibles and Potentially Avoidable Hospitalizations

    Data.gov (United States)

    U.S. Department of Health & Human Services — About 25 percent of the hospitalizations for dual eligible beneficiaries in 2005 were potentially avoidable. Medicare and Medicaid spending for those potentially...

  9. Food Waste Avoidance Actions in Food Retailing

    DEFF Research Database (Denmark)

    Kulikovskaja, Viktorija; Aschemann-Witzel, Jessica

    2017-01-01

    Food waste occurs throughout the entire food supply chain, from production to consumption of food in households. Retailers are in a unique position to contribute to food waste avoidance, not only by minimizing the amount of waste in their distribution channels but also by influencing consumer...... attitudes and behaviors. This explorative study aims to identify which food waste avoidance actions are conducted by retailers in Denmark, to which extent, and how they vary across food categories and supermarket chain. Based on an analysis of secondary and empirical data collected via observations...... at retail stores, the authors identify 22 food waste avoidance actions in Danish retail. The results provide new insights into food waste avoidance in retail. Based on the findings, suggestions for further research directions are developed that should serve to identify the most efficient customer targeted...

  10. GSA IT Reform Cost Savings/Avoidance

    Data.gov (United States)

    General Services Administration — GSA IT provides data related to Agency IT initiatives that save or avoid expenditures. This data is provided as a requirement of OMB's Integrated Data Collection...

  11. Toddlers at the Table: Avoiding Power Struggles

    Science.gov (United States)

    ... new food being offered. Avoid the Junk Food Trap Toddlers need to eat healthy to get the ... Nemours Foundation, iStock, Getty Images, Corbis, Veer, Science Photo Library, Science Source Images, Shutterstock, and Clipart.com

  12. Your Adolescent: Anxiety and Avoidant Disorders

    Science.gov (United States)

    ... other times, it develops into panic attacks and phobias. Identifying the Signs Anxiety disorders vary from teenager ... may begin to avoid normal activities and routines. Phobias Many fears of younger children are mild, passing, ...

  13. Avoid the Consequences of High Blood Pressure

    Science.gov (United States)

    ... Thromboembolism Aortic Aneurysm More Avoid the Consequences of High Blood Pressure Infographic Updated:Oct 31,2016 View a downloadable version of this infographic High Blood Pressure • Home • Get the Facts About HBP • Know Your ...

  14. Active Collision Avoidance for Planetary Landers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Advancements in radar technology have resulted in commercial, automotive collision avoidance radars. These radar systems typically use 37GHz or 77GHz interferometry...

  15. Dual Eligibles and Potentially Avoidable Hospitalizations

    Data.gov (United States)

    U.S. Department of Health & Human Services — About 25 percent of the hospitalizations for dual eligible beneficiaries in 2005 were potentially avoidable. Medicare and Medicaid spending for those potentially...

  16. 6 Tips to Avoid Medication Mistakes

    Science.gov (United States)

    ... For Consumers Consumer Updates 6 Tips to Avoid Medication Mistakes Share Tweet Linkedin Pin it More sharing ... dietary supplements you use. back to top Computerized Medication Box FDA has cleared for marketing the Electronic ...

  17. The challenges for scientists in avoiding plagiarism.

    Science.gov (United States)

    Fisher, E R; Partin, K M

    2014-01-01

    Although it might seem to be a simple task for scientists to avoid plagiarism and thereby an allegation of research misconduct, assessment of trainees in the Responsible Conduct of Research and recent findings from the National Science Foundation Office of Inspector General regarding plagiarism suggests otherwise. Our experiences at a land-grant academic institution in assisting researchers in avoiding plagiarism are described. We provide evidence from a university-wide multi-disciplinary course that understanding how to avoid plagiarism in scientific writing is more difficult than it might appear, and that a failure to learn the rules of appropriate citation may cause dire consequences. We suggest that new strategies to provide training in avoiding plagiarism are required.

  18. Packet Drop Avoidance for High-speed network transmission protocol

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Guojun

    2004-05-01

    As network bandwidth continues to grow and longer paths are used to exchange large scientific data between storage systems and GRID computation, it has become increasingly obvious that there is a need to deploy a packet drop avoidance mechanism into network transmission protocols. Current end-to-end congestion avoidance mechanisms used in Transmission Control Protocol (TCP) have worked well on low bandwidth delay product networks, but with newer high-bandwidth delay networks they have shown to be inefficient and prone to unstable. This is largely due to increased network bandwidth coupled with changes in internet traffic patterns. These changes come from a variety of new network applications that are being developed to take advantage of the increased network bandwidth. This paper will examine the end-to-end congestion avoidance mechanism and perform a step-by-step analysis of its theory. In addition we will propose an alternative approach developed as part of a new network transmission protocol. Our alternative protocol uses a packet drop avoidance (PDA) mechanism built on top of the maximum burst size (MBS) theory combined with a real-time available bandwidth algorithm.

  19. The vigilance-avoidance model of avoidant recognition: An ERP study under threat priming.

    Science.gov (United States)

    Zhai, Jing; Chen, Xu; Ma, Jianling; Yang, Qingqing; Liu, Ying

    2016-12-30

    Our study examined attachment-related electrophysiological differences in recognition using event-related potentials (ERPs) measured during a study-test paradigm after threat priming. We identified ERP correlates of recognition by comparing the ERPs of attachment-related positive and negative images between avoidant and secure attachment orientations. Our results revealed that the distribution of early old/new effects was broader in avoidant individuals than in secure individuals, and an early parietal old/new effect was observed in avoidant individuals, which reflected their implicit memory. The late old/new effect was found only in secure individuals when evoked by negative pictures, and was not observed in avoidant individuals. The results suggest that avoidant individuals adopt the "vigilance-avoidance" dual-process model to recognize both positive and negative attachment-related stimuli and carry out preferential familiarity matching at the automatic level and avoidant retrieval at the controlled-processing level.

  20. Banking deregulation and corporate tax avoidance

    Directory of Open Access Journals (Sweden)

    Bill B. Francis

    2017-06-01

    Full Text Available We investigate whether tax avoidance substitutes for external financing. We exploit interstate banking deregulation as a quasi-external shock to examine whether firms engage in less tax avoidance after banking deregulation, because of cheaper and easier access to credit from banks. We find no empirical evidence to support this substitutive relation, even for firms with higher financial constraints or firms with higher external financing dependence.

  1. Information Dilemmas and Blame-Avoidance Strategies

    DEFF Research Database (Denmark)

    Erik, Baekkeskov; Rubin, Olivier

    2016-01-01

    from day one about 2009 H1N1 flu. To explore why, this article links crisis information dilemmas to blame avoidance concepts from democratic political theories. We argue that greater Chinese transparency about infectious disease response reflects evolution in blame avoidance, from heavy reliance...... in place public health specialists and institutions as responsible for H1N1 information and responses, thereby insulating the top-tier leadership....

  2. Mobile Robot Collision Avoidance in Human Environments

    Directory of Open Access Journals (Sweden)

    Lingqi Zeng

    2013-01-01

    Full Text Available Collision avoidance is a fundamental requirement for mobile robots. Avoiding moving obstacles (also termed dynamic obstacles with unpredictable direction changes, such as humans, is more challenging than avoiding moving obstacles whose motion can be predicted. Precise information on the future moving directions of humans is unobtainable for use in navigation algorithms. Furthermore, humans should be able to pursue their activities unhindered and without worrying about the robots around them. In this paper, both active and critical regions are used to deal with the uncertainty of human motion. A procedure is introduced to calculate the region sizes based on worst‐case avoidance conditions. Next, a novel virtual force field‐based mobile robot navigation algorithm (termed QVFF is presented. This algorithm may be used with both holonomic and nonholonomic robots. It incorporates improved virtual force functions for avoiding moving obstacles and its stability is proven using a piecewise continuous Lyapunov function. Simulation and experimental results are provided for a human walking towards the robot and blocking the path to a goal location. Next, the proposed algorithm is compared with five state‐of‐the‐art navigation algorithms for an environment with one human walking with an unpredictable change in direction. Finally, avoidance results are presented for an environment containing three walking humans. The QVFF algorithm consistently generated collision‐free paths to the goal.

  3. The pathogen transmission avoidance theory of sexual selection

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C.

    1997-08-01

    The current theory that sexual selection results from female preference for males with good genes suffers from several problems. An alternative explanation, the pathogen transmission avoidance hypothesis, argues that the primary function of showy traits is to provide a reliable signal of current disease status, so that sick individuals can be avoided during mating. This study shows that a significant risk of pathogen transmission occurs during mating and that showy traits are reliable indicators of current disease status. The origin of female choosiness is argued to lie in a general tendency to avoid sick individuals, even in the absence of showy traits, which originate as exaggerations of normal traits that are indicative of good health (bright feathers, vigorous movement, large size). Thus, in this new model the origins of both showy traits and female choosiness are not problematic and there is no threshold effect. This model predicts that when the possession of male showy traits does not help to reduce disease in the female, showy traits are unlikely to occur. This case corresponds to thorough exposure of every animal to all group pathogens, on average, in large groups. Such species are shown with a large data set on birds to be less likely to exhibit showy traits. The good-genes model does not make this prediction. The pathogen transmission avoidance model can also lead to the evolution of showy traits even when selection is not effective against a given pathogen (e.g., when there is no heritable variation for resistance), but can result in selection for resistance if such genes are present. Monogamy is argued to reduce selection pressures for showy traits; data show monogamous species to be both less parasitized and less showy. In the context of reduction of pathogen transmission rates in showy populations, selection pressure becomes inversely frequency-dependent, which makes showy traits likely to be self-limiting rather than runaway.

  4. 南极Gerlache海峡海鸟的取食集群及食性%Feeding aggregation and diets of seabirds at Gerlache Strait, Antarctica

    Institute of Scientific and Technical Information of China (English)

    Marco FAVERO; Néstor Bubén CORIA

    2007-01-01

    Foraging associations between flying seabirds and penguins were studied from December 1997 to February 1998 at Cierva Point, Antarctic Peninsula. Observations were complemented with dietary information on the main species observed in aggregations. An average of 35.6±37.0 flying birds per aggregation was observed, almost all of them associated to chinstrap penguin Pygoscelis antarctica groups. The most common species were kelp gulls Larus dominicanus, South Polar skuas Catharacta maccormicki, pintado petrels Daption capensis and southern giant petrels Macronectes giganteus. The number of associations observed per sampling unit decreased as the season progressed, in some species accordingly with particular stage of their phenology. Antarctic krill Euphausia superba was particularly important in the diet of most abundant flying bird species in assemblages. The overlap index for krill sizes consumed give highest values in the comparisons between kelp gulls and chinstrap penguins. The foraging behaviour of flying birds suggested that prey was available near the surface for short time periods, likely facilitated by movements of krill avoiding penguin predation[Acta Zoologica Sinica 53(3):425-430,2007].%1997年12月至1998年2月,我们对南极半岛席尔瓦角善于飞翔海鸟与企鹅的取食关联性进行了研究,同时调查了取食集团中主要鸟种的食性.发现每个取食集团中有35.6-37.0只善于飞翔的海鸟,其中几乎都有纹颊企鹅群 (Pygoscelis antarctica),黑背鸥(Larus dominicanus)、灰贼鸥(Catharacta maccormicki)、花斑鹱(Daption capensis)和巨鹱(Macronectes giganteus)是各集团中最常见的鸟类.各取样单元内有相关性的种数随季节变化而减少,一些种类的减少与特定的物候期有关.南极磷虾(Euphausia superba)是绝大部分飞翔海鸟的主要食物,研究发现黑背鸥与纹颊企鹅所捕食的南极磷虾的大小最为接近.飞翔海鸟的觅食行为表明:在海面上短时停

  5. ADVERTISING AVOIDANCE PADA IKLAN DI MEDIA TELEVISI

    Directory of Open Access Journals (Sweden)

    Indah Dwi Pratama

    2016-01-01

    Full Text Available One factor that can interfere with the absorption rate of viewers on television advertisement is advertising avoidance which shows the difference between the number of viewers who watch advertisement programs and the number of viewers who watch television programs. The factors that affect advertising avoidance include the demography of the viewers (gender, age, area of residence, and social economic status, or SES, advertising attributes (the television stations, order of ads, genre of the program, and advertising sector, and competition (DayPart. The study attempted to measure the level of advertising avoidance in Indonesia and its relation to various factors that influence it by using the secondary data generated by Nielsen Audience Measurement Indonesia through Television Audience Measurement (TAM. The methods utilized consisted of the t-test independent sample, one way ANOVA, Tukey, Kruskal Wallis, and Dunn Bonferoni. The result showed that the level of advertising avoidance in Indonesia reached by 23%, with relatively similar results to the other studies in various countries. The hypothesis test results also showed a significant relationship between the advertising avoidance and demographic variables, advertising attributes, and competitions affecting this avoidance. On one hand, the findings of the study are expected to be useful for the advertisers to plan their advertisements on television so that they become more effective and efficient. On the other hand, television stations can utilize these findings as a development strategy to expand their audience segmentation and to accommodate the needs of the advertisers more optimally.Keywords: advertising avoidance, television advertisement, TAM, ANOVA, Tukey

  6. Seabird feathers as monitors of the levels and persistence of heavy metal pollution after the Prestige oil spill.

    Science.gov (United States)

    Moreno, Rocío; Jover, Lluís; Diez, Carmen; Sanpera, Carola

    2011-10-01

    We measured heavy metal concentrations in yellow-legged gulls (n = 196) and European shags (n = 189) in order to assess the temporal pattern of contaminant exposure following the Prestige oil spill in November 2002. We analysed Pb, Cu, Zn, Cr, Ni and V levels in chick feathers sampled at four colonies during seven post-spill years (2003-2009), and compared results with pre-spill levels obtained from feathers of juvenile shag corpses (grown in spring/summer 2002). Following the Prestige wreck, Cu (4.3-10 μg g(-1)) and Pb concentrations (1.0-1.4 μg g(-1)) were, respectively, between two and five times higher than pre-spill levels (1.5-3.6 and 0.1-0.4 μg g(-1)), but returned to previous background concentrations after three years. Our study highlights the suitability of chick feathers of seabirds for assessing the impact of oil spills on heavy metal contamination, and provides the best evidence to date on the persistence of oil pollution after the Prestige incident.

  7. EROD activity and stable isotopes in seabirds to disentangle marine food web contamination after the Prestige oil spill

    Energy Technology Data Exchange (ETDEWEB)

    Velando, Alberto, E-mail: avelando@uvigo.e [Departamento de Ecoloxia e Bioloxia Animal, Facultade de Ciencias, Universidade de Vigo, Campus As Lagoas, 36310 Vigo (Spain); Munilla, Ignacio [Departamento de Botanica, Facultade de Farmacia, Universidade de Santiago de Compostela, Santiago de Compostela (Spain); Lopez-Alonso, Marta [Departamento de Patoloxia Animal, Facultade de Veterinaria, Universidade de Santiago de Compostela, Lugo (Spain); Freire, Juan [Grupo de Recursos Marinos y Pesquerias Universidade da Coruna, A Coruna (Spain); Perez, Cristobal [Departamento de Ecoloxia e Bioloxia Animal, Facultade de Ciencias, Universidade de Vigo, Campus As Lagoas, 36310 Vigo (Spain)

    2010-05-15

    In this study, we measured via surgical sampling hepatic EROD activity in yellow-legged gulls from oiled and unoiled colonies, 17 months after the Prestige oil spill. We also analyzed stable isotope composition in feathers of the biopsied gulls, in an attempt to monitor oil incorporation into marine food web. We found that yellow-legged gulls in oiled colonies were being exposed to remnant oil as shown by hepatic EROD activity levels. EROD activity was related to feeding habits of individual gulls with apparent consequences on delayed lethality. Capture-recapture analysis of biopsied gulls suggests that the surgery technique did not affect gull survival, giving support to this technique as a monitoring tool for oil exposure assessment. Our study highlights the combination of different veterinary, toxicological and ecological methodologies as a useful approach for the monitoring of exposure to remnant oil after a large oil spill. - Two years after Prestige oil spill, seabirds were exposed to remnant oil related to their feeding habits with consequences on delayed lethality.

  8. Distribution and at-sea activity of a nocturnal seabird, the Bulwer's petrel Bulweria bulwerii, during the incubation period

    Science.gov (United States)

    Dias, Maria P.; Romero, Joana; Granadeiro, José Pedro; Catry, Teresa; Pollet, Ingrid L.; Catry, Paulo

    2016-07-01

    Bulwer's petrels are nocturnal seabirds that mostly prey on mesopelagic fauna. As aerial foragers and shallow divers, their feeding opportunities are limited by near-surface availability of their prey, which is highly variable both temporally (reflecting diurnal and lunar cycles) and spatially. Here we studied how Bulwer's petrels cope with these constraints by analysing their at-sea distribution and activity during the incubation period. We tracked the movements of 20 birds from Selvagem Grande (NE Atlantic) during a complete lunar cycle, and recorded 30 foraging trips that lasted 11 days on average. Birds were both distributed around the colony and in waters close to the Azorean archipelago (mid-Atlantic) located 1700 km away, and were significantly more active at night (especially just after sunset and before sunrise), when mesopelagic fauna is also closer to the sea surface due to their diel vertical migrations. Bulwer's petrels spent significantly more time flying during moonlight, although the effect of the moon was relatively weak (ca. 10-15% difference between moonlit and dark periods of the night), and not obvious when birds were foraging in mid-Atlantic waters, which were also targeted more often during full-moon. These results reveal key adaptations of the Bulwer's petrel to the highly dynamic ecology of its mesopelagic prey.

  9. Male-biased sex allocation in ageing parents; a longitudinal study in a long-lived seabird.

    Science.gov (United States)

    Vedder, Oscar; Bouwhuis, Sandra; Benito, María M; Becker, Peter H

    2016-08-01

    Optimal sex allocation is frequency-dependent, but senescence may cause behaviour at old age to be suboptimal. We investigated whether sex allocation changes with parental age, using 16 years of data comprising more than 2500 molecularly sexed offspring of more than 600 known-age parents in common terns (Sterna hirundo), slightly sexually size-dimorphic seabirds. We decomposed parental age effects into within-individual change and sex allocation-associated selective (dis)appearance. Individual parents did not differ consistently in sex allocation, but offspring sex ratios at fledging changed from female- to male-biased as parents aged. Sex ratios at hatching were not related to parental age, suggesting sons to outperform daughters after hatching in broods of old parents. Our results call for the integration of sex allocation theory with theory on ageing and demography, as a change in sex allocation with age per se will cause the age structure of a population to affect the frequency-dependent benefits and the age-specific strength of selection on sex allocation.

  10. Unifying quantitative life-history theory and field endocrinology to assess prudent parenthood in a long-lived seabird

    Science.gov (United States)

    Satterthwaite, W.H.; Kitaysky, A.S.; Hatch, Shyla A.; Piatt, J.F.; Mangel, M.

    2010-01-01

    Question: Can field measurements of stress hormones help us to assess the prudent parent hypothesis in a long-lived seabird? Organism: Black-legged kittiwake, Rissa tridactyla. Location: Duck and Gull Islands, Cook Inlet, Alaska, Methods: We examined the statistical relationship between the stress hormone corticosterone and mortality in black-legged kittiwakes. We built a demographic model of the kittiwake life cycle to determine whether the mortality rates associated with persisting in a breeding attempt despite high corticosterone caused the birds to sacrifice more lifetime reproductive output than they gain from one year's breeding. Results: The probability of apparent mortality increased with corticosterone, suggesting some birds incurred increased mortality risk for the sake of breeding. For Duck Island (low reproductive success), it appears birds sacrificed more lifetime reproductive success than a prudent parent would. On Gull Island, it appears most but possibly not all birds were behaving in ways consistent with theory, although definitive statements require larger samples of highly stressed birds. ?? 2010 William H. Satterthwaite.

  11. Global patterns of marine mammal, seabird, and sea turtle bycatch reveal taxa-specific and cumulative megafauna hotspots

    Science.gov (United States)

    Lewison, Rebecca L.; Crowder, Larry B.; Wallace, Bryan P.; Moore, Jeffrey E.; Cox, Tara; Zydelis, Ramunas; McDonald, Sara; DiMatteo, Andrew; Dunn, Daniel C.; Kot, Connie Y.; Bjorkland, Rhema; Kelez, Shaleyla; Soykan, Candan; Stewart, Kelly R.; Sims, Michelle; Boustany, Andre; Read, Andrew J.; Halpin, Patrick; Nichols, W. J.; Safina, Carl

    2014-01-01

    Recent research on ocean health has found large predator abundance to be a key element of ocean condition. Fisheries can impact large predator abundance directly through targeted capture and indirectly through incidental capture of nontarget species or bycatch. However, measures of the global nature of bycatch are lacking for air-breathing megafauna. We fill this knowledge gap and present a synoptic global assessment of the distribution and intensity of bycatch of seabirds, marine mammals, and sea turtles based on empirical data from the three most commonly used types of fishing gears worldwide. We identify taxa-specific hotspots of bycatch intensity and find evidence of cumulative impacts across fishing fleets and gears. This global map of bycatch illustrates where data are particularly scarce—in coastal and small-scale fisheries and ocean regions that support developed industrial fisheries and millions of small-scale fishers—and identifies fishing areas where, given the evidence of cumulative hotspots across gear and taxa, traditional species or gear-specific bycatch management and mitigation efforts may be necessary but not sufficient. Given the global distribution of bycatch and the mitigation success achieved by some fleets, the reduction of air-breathing megafauna bycatch is both an urgent and achievable conservation priority. PMID:24639512

  12. Biologging, remotely-sensed oceanography and the continuous plankton recorder reveal the environmental determinants of a seabird wintering hotspot.

    Science.gov (United States)

    Fort, Jérôme; Beaugrand, Grégory; Grémillet, David; Phillips, Richard A

    2012-01-01

    Marine environments are greatly affected by climate change, and understanding how this perturbation affects marine vertebrates is a major issue. In this context, it is essential to identify the environmental drivers of animal distribution. Here, we focused on the little auk (Alle alle), one of the world's most numerous seabirds and a major component in Arctic food webs. Using a multidisciplinary approach, we show how little auks adopt specific migratory strategies and balance environmental constraints to optimize their energy budgets. Miniature electronic loggers indicate that after breeding, birds from East Greenland migrate >2000 km to overwinter in a restricted area off Newfoundland. Synoptic data available from the Continuous Plankton Recorder (CPR) indicate that this region harbours some of the highest densities of the copepod Calanus finmarchicus found in the North Atlantic during winter. Examination of large-scale climatic and oceanographic data suggests that little auks favour patches of high copepod abundance in areas where air temperature ranges from 0°C to 5°C. These results greatly advance our understanding of animal responses to extreme environmental constraints, and highlight that information on habitat preference is key to identifying critical areas for marine conservation.

  13. Airborne Collision Avoidance System as a Cyber-Physical System

    Directory of Open Access Journals (Sweden)

    Andrei C. NAE

    2015-12-01

    Full Text Available In this paper the key concepts of ITS - Intelligent Transport Systems, CPS - Cyber-Physical Systems and SM - Smart Mobility are defined and correlated with the need for ACAS – Airborne Collision Avoidance System, as the last resort safety net and indispensable ingredient in civil aviation. Smart Mobility is addressed from a Cyber Physical-Systems perspective, detailing some of the elements that this entails. Here we consider the Air Transportations System of the future as a Cyber-Physical System and analyze the implications of doing so from different perspectives. The objective is to introduce a 4D collision avoidance shield technology which forms a last resort safety net technology for the next generation air transport (2050 and beyond. The new system will represent a step change over the performance of current technology. As conclusions, the benefits of implementing Transport Cyber-Physical Systems are discussed, as well as what this would require for future deployment.

  14. DAIDALUS: Detect and Avoid Alerting Logic for Unmanned Systems

    Science.gov (United States)

    Munoz, Cesar; Narkawicz, Anthony; Hagen, George; Upchurch, Jason; Dutle, Aaron; Consiglio, Maria; Chamberlain, James

    2015-01-01

    This paper presents DAIDALUS (Detect and Avoid Alerting Logic for Unmanned Systems), a reference implementation of a detect and avoid concept intended to support the integration of Unmanned Aircraft Systems into civil airspace. DAIDALUS consists of self-separation and alerting algorithms that provide situational awareness to UAS remote pilots. These algorithms have been formally specified in a mathematical notation and verified for correctness in an interactive theorem prover. The software implementation has been verified against the formal models and validated against multiple stressing cases jointly developed by the US Air Force Research Laboratory, MIT Lincoln Laboratory, and NASA. The DAIDALUS reference implementation is currently under consideration for inclusion in the appendices to the Minimum Operational Performance Standards for Unmanned Aircraft Systems presently being developed by RTCA Special Committee 228.

  15. Real-Time Fuzzy Obstacle Avoidance Using Directional Visual Perception

    Institute of Scientific and Technical Information of China (English)

    Huang Guoquan(黄国权); Rad A. B.; Wong Y. K.

    2004-01-01

    This paper presents a novel vision-based obstacle avoidance approach for the Autonomous Mobile Robot (AMR) with a Pan- Tilt-Zoom (PTZ) camera as its only sensing modality. The approach combines the morphological closing operation based on Sobel Edge Detection Operation and the (μ-kσ) thresholding technique to detect obstacles to soften the various lighting and ground floor effects. Both the morphology method and thresholding technique are computationally simple. The processing speed of the algorithm is fast enough to avoid some active obstacles. In addition, this approach takes into account the history obstacle effects on the current state. Fuzzy logic is used to control the behaviors of AMR as it navigates in the environment. All behaviors run concurrently and generate motor response solely based on vision perception. A priority based on subsumption coordinator selects the most appropriate response to direct the AMR away from obstacles. Validation of the proposed approach is done on a Pioneer 1 mobile robot.

  16. Efficient Avoidance of the Penalty Zone in Human Eye Movements

    Science.gov (United States)

    Theeuwes, Jan

    2016-01-01

    People use eye movements extremely effectively to find objects of interest in a cluttered visual scene. Distracting, task-irrelevant attention capturing regions in the visual field should be avoided as they jeopardize the efficiency of search. In the current study, we used eye tracking to determine whether people are able to avoid making saccades to a predetermined visual area associated with a financial penalty, while making fast and accurate saccades towards stimuli placed near the penalty area. We found that in comparison to the same task without a penalty area, the introduction of a penalty area immediately affected eye movement behaviour: the proportion of saccades to the penalty area was immediately reduced. Also, saccadic latencies increased, but quite modestly, and mainly for saccades towards stimuli near the penalty area. We conclude that eye movement behaviour is under efficient cognitive control and thus quite flexible: it can immediately be adapted to changing environmental conditions to improve reward outcome. PMID:27930724

  17. Hear no evil: The effect of auditory warning signals on avian innate avoidance, learned avoidance and memory

    Directory of Open Access Journals (Sweden)

    Emma C. SIDDALL, Nicola M. MARPLES

    2011-04-01

    Full Text Available Many aposematic insect species advertise their toxicity to potential predators using olfactory and auditory signals, in addition to visual signals, to produce a multimodal warning display. The olfactory signals in these displays may have interesting effects, such as eliciting innate avoidance against novel colored prey, or improving learning and memory of defended prey. However, little is known about the effects of such ancillary signals when they are auditory rather than olfactory. The few studies that have investigated this question have provided conflicting results. The current study sought to clarify and extend understanding of the effects of prey auditory signals on avian predator responses. The domestic chick Gallus gallus domesticus was used as a model avian predator to examine how the defensive buzzing sound of a bumblebee Bombus terrestris affected the chick’s innate avoidance behavior, and the learning and memory of prey avoidance. The results demonstrate that the buzzing sound had no effect on the predator’s responses to unpalatable aposematically colored crumbs, suggesting that the agitated buzzing of B. terrestris may provide no additional protection from avian predators [Current Zoology 57 (2: 197–207, 2011].

  18. Is avoiding an aversive outcome rewarding? Neural substrates of avoidance learning in the human brain.

    Science.gov (United States)

    Kim, Hackjin; Shimojo, Shinsuke; O'Doherty, John P

    2006-07-01

    Avoidance learning poses a challenge for reinforcement-based theories of instrumental conditioning, because once an aversive outcome is successfully avoided an individual may no longer experience extrinsic reinforcement for their behavior. One possible account for this is to propose that avoiding an aversive outcome is in itself a reward, and thus avoidance behavior is positively reinforced on each trial when the aversive outcome is successfully avoided. In the present study we aimed to test this possibility by determining whether avoidance of an aversive outcome recruits the same neural circuitry as that elicited by a reward itself. We scanned 16 human participants with functional MRI while they performed an instrumental choice task, in which on each trial they chose from one of two actions in order to either win money or else avoid losing money. Neural activity in a region previously implicated in encoding stimulus reward value, the medial orbitofrontal cortex, was found to increase, not only following receipt of reward, but also following successful avoidance of an aversive outcome. This neural signal may itself act as an intrinsic reward, thereby serving to reinforce actions during instrumental avoidance.

  19. Towards better patient care: drugs to avoid.

    Science.gov (United States)

    2013-04-01

    Common sense dictates that one should choose tried and tested drugs with proven, concrete benefits that outweigh their adverse effects. Many new drugs are approved each year, often despite a lack of solid evidence that they are any better than existing treatments. Worse, some are approved despite being less effective or more harmful than current options. Massive promotion is used to ensure that such drugs achieve a positive image in the eyes of healthcare professionals and patients. Renowned "opinion leaders" intervene in their favour at conferences and in specialist media, and their opinions are further propagated by specialists in the field. Finally, campaigns in the lay media are used to highlight the target illness, encouraging patients to request a prescription. New data sometimes show that older, initially promising drugs are less effective or more harmful than first thought. For all these reasons, many drugs that are now present on the market are more harmful than beneficial and should be avoided. Unfortunately, negative assessment data and warnings are often drowned in the flood of promotion and advertising. Front-line healthcare professionals who are determined to act in their patients' best interests can find themselves swimming against a tide of specialist opinion, marketing authorisation, and reimbursement decisions. By leaving drugs that are more harmful than beneficial on the market and contenting themselves with simple half-measures, healthcare authorities are failing in their duty to protect patients. Prescrire, a journal funded solely by its subscribers, does not seek to do the work of health authorities, and does not have the means to do so. Prescrire's goal is simply to help healthcare professionals provide better care. The following text lists the principal drugs that we consider more harmful than beneficial, based on our reviews published between 2010 and 2012 in our French edition. These drugs should not be used. Patients and healthcare

  20. Avoiding barriers in control of mowing robot

    Institute of Scientific and Technical Information of China (English)

    QIU Bai-jing; QIAN Guo-hong; XIANG Zhong-ping; LI Zuo-peng

    2006-01-01

    Due to complicated barriers,it is difficult to track the path of the mowing robot and to avoid barriers.In order to solve the problem,a method based on distance-measuring sensors and fuzzy control inputs was proposed.Its track was composed of beelines and was easy to tail.The fuzzy control inputs were based on the front barrier distance and the difference between the left and right barrier distance measured by ultrasonic sensors;the output was the direction angle.The infrared sensors around the robot improved its safety in avoiding barriers.The result of the method was feasible,agile,and stable.The distance between the robot and the barriers could be changed by altering the inputs and outputs of fuzzy control and the length of the beelines.The disposed sensors can fulfill the need of the robot in avoiding barriers.

  1. Cod avoidance by area regulations in Kattegat

    DEFF Research Database (Denmark)

    Eliasen, Søren Qvist

    2014-01-01

    presents two initiatives for cod avoidance in Kattegat; a fisher initiative sharing information about cod bycatch which could lead to real time closures in areas with high bycatch of juveniles, for vessels with low cod quota to avoid catch of all cod, and a Danish Swedish Government initiative of permanent......The article examines the experiences of two initiatives of cod avoidance by area regulations in the Kattegat in the light of the upcoming discard ban in EU fisheries. The first section highlights elements of the discard ban in the reformed EU Common Fisheries Policy (CFP). The second section...... and temporary area closures in Kattegat. The third section discusses the lessons learned in the light of implementation of the discard ban. The fourth section sums up the lessons learned; Regional measures of implementation of the discard ban should include all vessels with quota in the region to be regarded...

  2. Chloroplast avoidance movement reduces photodamage in plants.

    Science.gov (United States)

    Kasahara, Masahiro; Kagawa, Takatoshi; Oikawa, Kazusato; Suetsugu, Noriyuki; Miyao, Mitsue; Wada, Masamitsu

    When plants are exposed to light levels higher than those required for photosynthesis, reactive oxygen species are generated in the chloroplasts and cause photodamage. This can occur even under natural growth conditions. To mitigate photodamage, plants have developed several protective mechanisms. One is chloroplast avoidance movement, in which chloroplasts move from the cell surface to the side walls of cells under high light conditions, although experimental support is still awaited. Here, using different classes of mutant defective in chloroplast avoidance movement, we show that these mutants are more susceptible to damage in high light than wild-type plants. Damage of the photosynthetic apparatus and subsequent bleaching of leaf colour and necrosis occur faster under high light conditions in the mutants than in wild-type plants. We conclude that chloroplast avoidance movement actually decreases the amount of light absorption by chloroplasts, and might therefore be important to the survival of plants under natural growth conditions.

  3. Engaging Math-Avoidant College Students

    Directory of Open Access Journals (Sweden)

    M. Paul Latiolais

    2009-07-01

    Full Text Available This paper is an informal, personal account of how we, as two college teachers, became interested in math anxiety, decided to explore it amongst students at our institution in order to inform our teaching, and became convinced that the massive problem is math avoidance. We tried discussion groups, but few students attended, although those that did made useful suggestions. Thus informed, we designed an innovative course, Confronting College Mathematics as a Humanities course with the possibility of credit toward the math requirement, but it was undersubscribed in its first offering and had to be canceled. How can we get college students who avoid math to break through the barrier of math avoidance? We have now begun to explore a new approach: Second Life, where students can engage math—and quantitative literacy—virtually, and anonymously.

  4. Learning processes underlying avoidance of negative outcomes.

    Science.gov (United States)

    Andreatta, Marta; Michelmann, Sebastian; Pauli, Paul; Hewig, Johannes

    2017-04-01

    Successful avoidance of a threatening event may negatively reinforce the behavior due to activation of brain structures involved in reward processing. Here, we further investigated the learning-related properties of avoidance using feedback-related negativity (FRN). The FRN is modulated by violations of an intended outcome (prediction error, PE), that is, the bigger the difference between intended and actual outcome, the larger the FRN amplitude is. Twenty-eight participants underwent an operant conditioning paradigm, in which a behavior (button press) allowed them to avoid a painful electric shock. During two learning blocks, participants could avoid an electric shock in 80% of the trials by pressing one button (avoidance button), or by not pressing another button (punishment button). After learning, participants underwent two test blocks, which were identical to the learning ones except that no shocks were delivered. Participants pressed the avoidance button more often than the punishment button. Importantly, response frequency increased throughout the learning blocks but it did not decrease during the test blocks, indicating impaired extinction and/or habit formation. In line with a PE account, FRN amplitude to negative feedback after correct responses (i.e., unexpected punishment) was significantly larger than to positive feedback (i.e., expected omission of punishment), and it increased throughout the blocks. Highly anxious individuals showed equal FRN amplitudes to negative and positive feedback, suggesting impaired discrimination. These results confirm the role of negative reinforcement in motivating behavior and learning, and reveal important differences between high and low anxious individuals in the processing of prediction errors.

  5. Telerobotics with whole arm collision avoidance

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelmsen, K.; Strenn, S.

    1993-09-01

    The complexity of teleorbotic operations in a cluttered environment is exacerbated by the need to present collision information to the operator in an understandable fashion. In addition to preventing movements which will cause collisions, a system providing some form of virtual force reflection (VFR) is desirable. With this goal in mind, Lawrence Livermore National Laboratory (LLNL) has installed a kinematically master/slave system and developed a whole arm collision avoidance system which interacts directly with the telerobotic controller. LLNL has also provided a structure to allow for automated upgrades of workcell models and provide collision avoidance even in a dynamically changing workcell.

  6. Reproductive ecology of seabirds at Middleton Island, Alaska, 15-24 June 1983: Trip report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Middleton Island harbors the largest colony of Pelagic Cormorants and Black-legged Kittiwakes in the Gulf of Alaska. Goals of the study were to assess the current...

  7. Low-Cost Avoidance Behaviors Are Resistant To Fear Extinction In Humans

    Directory of Open Access Journals (Sweden)

    Bram eVervliet

    2015-12-01

    Full Text Available Elevated levels of fear and avoidance are core symptoms across the anxiety disorders. It has long been known that fear serves to motivate avoidance. Consequently, fear extinction has been the primary focus in pre-clinical anxiety research for decades, under the implicit assumption that removing the motivator of avoidance (fear would automatically mitigate the avoidance behaviors as well. Although this assumption has intuitive appeal, it has received little scientific scrutiny. The scarce evidence from animal studies is mixed, while the assumption remains untested in humans. The current study applied an avoidance conditioning protocol in humans to investigate the effects of fear extinction on the persistence of low-cost avoidance. Online danger-safety ratings and skin conductance responses documented the dynamics of conditioned fear across avoidance and extinction phases. Anxiety- and avoidance-related questionnaires explored individual differences in rates of avoidance. Participants first learned to click a button during a predictive danger signal, in order to cancel an upcoming aversive electrical shock (avoidance conditioning. Next, fear extinction was induced by presenting the signal in the absence of shocks while button-clicks were prevented (by removing the button in Experiment 1, or by instructing not to click the button in Experiment 2. Most importantly, post-extinction availaibility of the button caused a significant return of avoidant button-clicks. In addition, trait-anxiety levels correlated positively with rates of avoidance during a predictive safety signal, and with the rate of pre- to post-extinction decrease during this signal. Fear measures gradually decreased during avoidance conditioning, as participants learned that button-clicks effectively canceled the shock. Preventing button-clicks elicited a sharp increase in fear, which subsequently extinguished. Fear remained low during avoidance testing, but danger-safety ratings

  8. Low-Cost Avoidance Behaviors are Resistant to Fear Extinction in Humans.

    Science.gov (United States)

    Vervliet, Bram; Indekeu, Ellen

    2015-01-01

    Elevated levels of fear and avoidance are core symptoms across the anxiety disorders. It has long been known that fear serves to motivate avoidance. Consequently, fear extinction has been the primary focus in pre-clinical anxiety research for decades, under the implicit assumption that removing the motivator of avoidance (fear) would automatically mitigate the avoidance behaviors as well. Although this assumption has intuitive appeal, it has received little scientific scrutiny. The scarce evidence from animal studies is mixed, while the assumption remains untested in humans. The current study applied an avoidance conditioning protocol in humans to investigate the effects of fear extinction on the persistence of low-cost avoidance. Online danger-safety ratings and skin conductance responses documented the dynamics of conditioned fear across avoidance and extinction phases. Anxiety- and avoidance-related questionnaires explored individual differences in rates of avoidance. Participants first learned to click a button during a predictive danger signal, in order to cancel an upcoming aversive electrical shock (avoidance conditioning). Next, fear extinction was induced by presenting the signal in the absence of shocks while button-clicks were prevented (by removing the button in Experiment 1, or by instructing not to click the button in Experiment 2). Most importantly, post-extinction availability of the button caused a significant return of avoidant button-clicks. In addition, trait-anxiety levels correlated positively with rates of avoidance during a predictive safety signal, and with the rate of pre- to post-extinction decrease during this signal. Fear measures gradually decreased during avoidance conditioning, as participants learned that button-clicks effectively canceled the shock. Preventing button-clicks elicited a sharp increase in fear, which subsequently extinguished. Fear remained low during avoidance testing, but danger-safety ratings increased again when

  9. Development of a Measure of Experiential Avoidance: The Multidimensional Experiential Avoidance Questionnaire

    Science.gov (United States)

    Gamez, Wakiza; Chmielewski, Michael; Kotov, Roman; Ruggero, Camilo; Watson, David

    2011-01-01

    Experiential avoidance (EA) has been conceptualized as the tendency to avoid negative internal experiences and is an important concept in numerous conceptualizations of psychopathology as well as theories of psychotherapy. Existing measures of EA have either been narrowly defined or demonstrated unsatisfactory internal consistency and/or evidence…

  10. Myopic Regret Avoidance: Feedback Avoidance and Learning in Repeated Decision Making

    Science.gov (United States)

    Reb, Jochen; Connolly, Terry

    2009-01-01

    Decision makers can become trapped by "myopic regret avoidance" in which rejecting feedback to avoid short-term "outcome regret" (regret associated with counterfactual outcome comparisons) leads to reduced learning and greater long-term regret over continuing poor decisions. In a series of laboratory experiments involving repeated choices among…

  11. Avoided by association: acquisition, extinction, and renewal of avoidance tendencies toward conditioned fear stimuli

    NARCIS (Netherlands)

    A.M. Krypotos; M. Effting; I. Arnaudova; M. Kindt; T. Beckers

    2013-01-01

    Traditional theoretical models hold that avoidance reflects the interplay of Pavlovian and instrumental learning. Here we suggest that avoidance tendencies to intrinsically neutral cues may be established by mere Pavlovian association. Following fear conditioning, in which pictures of one object wer

  12. Reasonable Avoidability, Responsibility and Lifestyle Diseases

    DEFF Research Database (Denmark)

    Andersen, Martin Marchman

    2012-01-01

    In “Health, Luck and Justice” Shlomi Segall argues for a luck egalitarian approach to justice in health care. As the basis for a just distribution he suggests a principle of Reasonable Avoidability, which he takes to imply that we do not have justice-based reasons to treat diseases brought about ...

  13. Oscillations in two-person avoidance control

    CERN Document Server

    Kish, Lazar

    2016-01-01

    Social interaction dynamics are a special type of group interactions that play a large part in our everyday lives. They dictate how and with whom a certain individual will interact. One of such interactions can be termed "avoidance control". This everyday situation occurs when two fast-walking persons suddenly realize that they are on a frontal collision course and begin maneuvering to avoid collision. If the two walkers' initial maneuverings are in the same direction that can lead to oscillations that lengthen time required to reach a stable avoidance trajectory. We introduce a dynamical model with a feedback loop to understand the origin and properties of this oscillation. For the emergence of the oscillatory behavior, two conditions must be satisfied: i) the persons must initiate the avoidance maneuver in the same direction; ii) the time delays in the feedback loop must reverse the phase of the players' positions at the oscillation frequency. The oscillation can be terminated at any time if one of the walk...

  14. Avoidable costs of comprehensive case management.

    Science.gov (United States)

    Issel, L M; Anderson, R A

    1999-01-01

    Comprehensive case management has become an industry standard and its pervasiveness raises questions about the ubiquitous need for this service. Analyzed from the perspective of transaction cost analysis and access, we argue that in some cases comprehensive case management is an avoidable cost incurred because of system problems that limit access to otherwise eligible clients. Implications are discussed.

  15. Doppler micro sense and avoid radar

    Science.gov (United States)

    Gorwara, Ashok; Molchanov, Pavlo; Asmolova, Olga

    2015-10-01

    There is a need for small Sense and Avoid (SAA) systems for small and micro Unmanned Aerial Systems (UAS) to avoid collisions with obstacles and other aircraft. The proposed SAA systems will give drones the ability to "see" close up and give them the agility to maneuver through tight areas. Doppler radar is proposed for use in this sense and avoid system because in contrast to optical or infrared (IR) systems Doppler can work in more harsh conditions such as at dusk, and in rain and snow. And in contrast to ultrasound based systems, Doppler can better sense small sized obstacles such as wires and it can provide a sensing range from a few inches to several miles. An SAA systems comprised of Doppler radar modules and an array of directional antennas that are distributed around the perimeter of the drone can cover the entire sky. These modules are designed so that they can provide the direction to the obstacle and simultaneously generate an alarm signal if the obstacle enters within the SAA system's adjustable "Protection Border". The alarm signal alerts the drone's autopilot to automatically initiate an avoidance maneuver. A series of Doppler radar modules with different ranges, angles of view and transmitting power have been designed for drones of different sizes and applications. The proposed Doppler radar micro SAA system has simple circuitry, works from a 5 volt source and has low power consumption. It is light weight, inexpensive and it can be used for a variety of small unmanned aircraft.

  16. Organising European technical documentation to avoid duplication.

    Science.gov (United States)

    Donawa, Maria

    2006-04-01

    The development of comprehensive accurate and well-organised technical documentation that demonstrates compliance with regulatory requirements is a resource-intensive, but critically important activity for medical device manufacturers. This article discusses guidance documents and method of organising technical documentation that may help avoid costly and time-consuming duplication.

  17. Reducing avoidable pressure ulcers in the community.

    Science.gov (United States)

    Parnham, Alison; Pankhurst, Sarah; Dabell, Wendy

    2015-02-27

    The elimination of avoidable pressure ulcers remains a challenge in healthcare provision, represents an increasing financial burden on resources and continues to affect patients' quality of life. Many pressure ulcers are deemed to be avoidable and there are several factors that can influence this, including the development of a care delivery system and a service delivery strategy that incorporate a comprehensive structure, a meticulous process and measurable outcomes. Nottingham CityCare developed a strategy to reduce avoidable pressure ulcers. The implementation of the strategy in an inner city community setting is discussed. The importance of eliminating pressure ulcers is explored, and the barriers to care delivery are reviewed, demonstrating how a new culture in clinical practice can ensure the elimination of avoidable pressure ulcers. The challenges within the implementation process are reflected on and the implementation of the SSKIN (Surface, Skin inspection, Keep your patient moving, Incontinence and moisture, Nutrition and hydration) phenomenon is reviewed in relation to care delivery, record-keeping and evaluation.

  18. Avoidance Motivation and Conservation of Energy

    NARCIS (Netherlands)

    Roskes, Marieke; Elliot, Andrew J.; Nijstad, Bernard A.; De Dreu, Carsten K. W.

    2013-01-01

    Compared to approach motivation, avoidance motivation evokes vigilance, attention to detail, systematic information processing, and the recruitment of cognitive resources. From a conservation of energy perspective it follows that people would be reluctant to engage in the kind of effortful cognitive

  19. Avoidance Motivation and Conservation of Energy

    NARCIS (Netherlands)

    Roskes, Marieke; Elliot, Andrew J.; Nijstad, Bernard A.; De Dreu, Carsten K. W.

    Compared to approach motivation, avoidance motivation evokes vigilance, attention to detail, systematic information processing, and the recruitment of cognitive resources. From a conservation of energy perspective it follows that people would be reluctant to engage in the kind of effortful cognitive

  20. Simple Obstacle Avoidance Algorithm for Rehabilitation Robots

    NARCIS (Netherlands)

    Stuyt, F.H.A.; Römer, G.R.B.; Stuyt, H.J.A.

    2007-01-01

    The efficiency of a rehabilitation robot is improved by offering record-and-replay to operate the robot. While automatically moving to a stored target (replay) collisions of the robot with obstacles in its work space must be avoided. A simple, though effective, generic and deterministic algorithm fo

  1. Rewarding peak avoidance: the Dutch 'Spitsmijden' projects

    NARCIS (Netherlands)

    Knockaert, J.; Bakens, J.; Ettema, D.F.; Verhoef, E.

    2011-01-01

    The Dutch road network is becoming increasingly congested. In late 2006, a group of companies, universities and government institutions established the Spitsmijden project. ‘Spitsmijden’ is the Dutch term for ‘avoiding the peak’. This joint initiative aimed to identify and assess a short-term

  2. Obesity and Healthcare Avoidance: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Robert D McGuigan

    2015-03-01

    Full Text Available This review addresses the issue of health care avoidance and obesity. English language journal articles published between 1990 and 2012 that addressed the review question|“is being overweight or obese an unrecognized factor in healthcare avoidance?” were located using major databases. A modified JADAD scoring system was then used to assess papers. Ten papers were identified which directly addressed the review question. A positive relationship exists between obesity and healthcare avoidance. The major contributory factors were being female, have a diagnosed mental health problem and perceived or actual bias and discrimination by health professionals. The review also highlights the importance of the relationship between healthcare professionals and their patients, and the physical environment in which interactions occur as these may contribute to avoidance behaviors. Concern about obesity is rising and while there has been much discussion about strategies to reduce obesity this review highlights the need for thinking more broadly about the way in which overweight and obese individuals interact with preventative health strategies.

  3. Proactive strategies to avoid infectious disease.

    Science.gov (United States)

    Stevenson, Richard J; Case, Trevor I; Oaten, Megan J

    2011-12-12

    Infectious disease exerts a large selective pressure on all organisms. One response to this has been for animals to evolve energetically costly immune systems to counter infection, while another--the focus of this theme issue--has been the evolution of proactive strategies primarily to avoid infection. These strategies can be grouped into three types, all of which demonstrate varying levels of interaction with the immune system. The first concerns maternal strategies that function to promote the immunocompetence of their offspring. The second type of strategy influences mate selection, guiding the selection of a healthy mate and one who differs maximally from the self in their complement of antigen-coding genes. The third strategy involves two classes of behaviour. One relates to the capacity of the organisms to learn associations between cues indicative of pathogen threat and immune responses. The other relates to prevention and even treatment of infection through behaviours such as avoidance, grooming, quarantine, medicine and care of the sick. In humans, disease avoidance is based upon cognition and especially the emotion of disgust. Human disease avoidance is not without its costs. There is a propensity to reject healthy individuals who just appear sick--stigmatization--and the system may malfunction, resulting in various forms of psychopathology. Pathogen threat also appears to have been a highly significant and unrecognized force in shaping human culture so as to minimize infection threats. This cultural shaping process--moralization--can be co-opted to promote human health.

  4. Detect and Avoid (DAA) Automation Maneuver Study

    Science.gov (United States)

    2017-02-01

    Participation was limited to military rated pilots and civilian pilots with full Instrument Flight Rules ( IFR ) ratings. Recent experience (within the last two...Avoidance IFR = Instrument Flight Rules IRB = Institutional Review Board VSCS = Vigilant Spirit Control Station TSD = Tactical Situation Display

  5. HOW TO AVOID SEXIST LANGUAGE IN ENGLISH

    Institute of Scientific and Technical Information of China (English)

    HuZhiqing

    2004-01-01

    Use of Sexist language is one of the serious yet often-neglected mistakes in the English writing and speaking of Chineselearners of English. Sexist language in English can be classifiedinto two categories : ambiguity of referent and stereotyping. Thispaper focuses on some common sexist language in the Englishwriting and speaking of Chinese learners of English and givessome suggestions about how to avoid them.

  6. The Netherlands Bird Avoidance Model, Final Report

    NARCIS (Netherlands)

    Shamoun-Baranes, J.; Bouten, W.; Sierdsema, H.; van Belle, J.; van Gasteren, J.R.; van Loon, E.E.

    2006-01-01

    The NL-BAM was developed as a web-based decision support tool to be used by the bird hazard avoidance experts in the ecology unit of the Royal Netherlands Air Force. The NL-BAM will be used together with the ROBIN 4 radar system to provide BirdTAMS, for real time warnings and flight planning and to

  7. Pathological Demand Avoidance: Exploring the Behavioural Profile

    Science.gov (United States)

    O'Nions, Elizabeth; Viding, Essi; Greven, Corina U; Ronald, Angelica; Happé, Francesca

    2014-01-01

    "Pathological Demand Avoidance" is a term increasingly used by practitioners in the United Kingdom. It was coined to describe a profile of obsessive resistance to everyday demands and requests, with a tendency to resort to "socially manipulative" behaviour, including outrageous or embarrassing acts. Pathological demand…

  8. [Avoidance of patient-prosthesis mismatch].

    Science.gov (United States)

    Sakamoto, Y; Hashimoto, K

    2006-04-01

    To minimize the incidence of patient-prosthesis mismatch (PPM), we have routinely adopted aortic root enlargement to avoid PPM for patients with small aortic annulus. The aim of this study was to review our strategy of avoiding PPM. The Carpentier-Edwards Perimount (CEP) valves were implanted in 53 patients who were mostly aged over 65 and the St. Jude Medical (SJM) mechanical valves were used in 128 patients aged under 65. A standard 21-mm SJM valve was used in only 3 patients and no 19-mm valves were employed. However, 19-mm CEP valves were used in 12 patients with a small body surface area (1.43 +/- 0.14 m2). Of these, 26 patients (14.4%) who had a small aortic annulus and 24 patients aged under 65 underwent aortic root enlargement. No patient receiving an SJM valve had an projected indexed effective orifice area (EOAI) small annulus, the first choice for avoiding PPM is aortic annular enlargement, which may be avoided by high performance mechanical valves with larger EOA.

  9. Teaching Preschool Children to Avoid Poison Hazards

    Science.gov (United States)

    Dancho, Kelly A.; Thompson, Rachel H.; Rhoades, Melissa M.

    2008-01-01

    We evaluated the effectiveness of group safety training and in situ feedback and response interruption to teach preschool children to avoid consuming potentially hazardous substances. Three children ingested ambiguous substances during a baited baseline assessment condition and continued to ingest these substances following group safety training.…

  10. Hydrofluoric acid on dentin should be avoided.

    NARCIS (Netherlands)

    Loomans, B.A.C.; Mine, A.; Roeters, F.J.M.; Opdam, N.J.M.; Munck, J. De; Huysmans, M.C.D.N.J.M.; Meerbeek, B. Van

    2010-01-01

    Hydrofluoric acid can be used for intra-oral repair of restorations. Contamination of tooth substrate with hydrofluoric acid cannot always be avoided. OBJECTIVES: To investigate the bonding effectiveness to hydrofluoric acid contaminated dentin by, micro-tensile bond strength testing, SEM and TEM. M

  11. Wide range of metallic and organic contaminants in various tissues of the Antarctic prion, a planktonophagous seabird from the Southern Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Fromant, Aymeric [Centre d' Etudes Biologiques de Chizé, UMR 7372 CNRS—Université de La Rochelle, 79360 Villiers-en-Bois (France); Carravieri, Alice, E-mail: carravieri@cebc.cnrs.fr [Centre d' Etudes Biologiques de Chizé, UMR 7372 CNRS—Université de La Rochelle, 79360 Villiers-en-Bois (France); Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS—Université de la Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Bustamante, Paco [Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS—Université de la Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Labadie, Pierre; Budzinski, Hélène; Peluhet, Laurent [Université de Bordeaux, UMR 5805 EPOC (LPTC Research Group), Université Bordeaux, 351 Cours de la Libération, F 33405 Talence Cedex (France); Churlaud, Carine [Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS—Université de la Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Chastel, Olivier; Cherel, Yves [Centre d' Etudes Biologiques de Chizé, UMR 7372 CNRS—Université de La Rochelle, 79360 Villiers-en-Bois (France)

    2016-02-15

    ABSTRACT: Trace elements (n = 14) and persistent organic pollutants (POPs, n = 30) were measured in blood, liver, kidney, muscle and feathers of 10 Antarctic prions (Pachyptila desolata) from Kerguelen Islands, southern Indian Ocean, in order to assess their concentrations, tissue distribution, and inter-tissue and inter-contaminant relationships. Liver, kidney and feathers presented the highest burdens of arsenic, cadmium and mercury, respectively. Concentrations of cadmium, copper, iron, and zinc correlated in liver and muscle, suggesting that uptake and pathways of metabolism and storage were similar for these elements. The major POPs were 4,4′-DDE, mirex, PCB-153 and PCB-138. The concentrations and tissue distribution patterns of environmental contaminants were overall in accordance with previous results in other seabirds. Conversely, some Antarctic prions showed surprisingly high concentrations of BDE-209. This compound has been rarely observed in seabirds before, and its presence in Antarctic prions could be due to the species feeding habits or to the ingestion of plastic debris. Overall, the study shows that relatively lower trophic level seabirds (zooplankton-eaters) breeding in the remote southern Indian Ocean are exposed to a wide range of environmental contaminants, in particular cadmium, selenium and some emerging-POPs, which merits further toxicological investigations. - Highlights: • Trace elements and POPs were measured in various tissues of 10 Antarctic prions. • Residue diversity was notable given the species' small size and low trophic position. • Cd, Se, BDE 183 and 209 showed noticeably high internal tissue concentrations. • Several POPs showed inter- and intra-tissue correlations, indicating co-exposure. • Blood was validated as a good bioindicator of internal tissue As and Hg levels.

  12. A new approach to study of seabird-fishery overlap: Connecting chick feeding with parental foraging and overlap with fishing vessels

    Directory of Open Access Journals (Sweden)

    Junichi Sugishita

    2015-07-01

    Full Text Available Incidental fisheries bycatch is recognised as a major threat to albatross populations worldwide. However, fishery discards and offal produced in large quantities might benefit some scavenging seabirds. Here, we demonstrate an integrated approach to better understand the ecological ramifications of fine-scale overlap between seabirds and fisheries. As a case study, we examined whether foraging in association with a fishing vessel is advantageous for chick provisioning in terms of quantity of food delivered to chicks, in northern royal albatross (Diomedea sanfordi at Taiaroa Head, New Zealand. Fine-scale overlap between albatrosses and vessels was quantified by integrating GPS tracking and Vessel Monitoring Systems (VMS. Meal size delivered to chicks was measured using custom-designed nest balances, and monitoring of attendance of adults fitted with radio transmitters was used in conjunction with time-lapse photography at the nest allowed us to allocate each feeding event to a specific parent. The combination of these techniques enabled comparison of meal sizes delivered to chicks with parental foraging trip durations with or without fishing vessels association. A total of 45 foraging trips and associated chick feeding events were monitored during the chick-rearing period in 2012. Differences in the meal size and foraging trip duration relative to foraging overlap with fisheries were examined using a linear mixed-effect model, adjusted for chick age. Our results, based on three birds, suggest that foraging in association with vessels does not confer an advantage for chick feeding for this population that demonstrated low rates of overlap while foraging. The integrated research design presented can be applied to other seabird species that are susceptible to bycatch, and offers a valuable approach to evaluate habitat quality by linking habitat use and foraging success in terms of total amount of food delivered to offspring.

  13. Measuring Patients’ Attachment Avoidance in Psychotherapy: Development of the Attachment Avoidance in Therapy Scale (AATS

    Directory of Open Access Journals (Sweden)

    András Láng

    2012-11-01

    Full Text Available A new scale measuring patient-therapist attachment avoidance was developed. Attachment Avoidance in Therapy Scale is a new measure based on the Bartholomew model of adult attachment (Bartholomew & Horowitz, 1991 and the Experience in Close Relationships Scale (Brennan, Clark, & Shaver, 1998 to measure patients’ attachment avoidance towards therapists. With 112 patient-therapist dyads participating in the study, validation of a preliminary scale – measuring both attachment anxiety and attachment avoidance in therapy – took place using therapists’ evaluations of patients’ relational behavior and patients’ self-reports about their attitude toward psychotherapy. Analysis of the data revealed six underlying scales. Results showed all six scales to be reliable. Validation of scales measuring attachment anxiety failed. The importance of Attachment Avoidance in Therapy Scale and its subscales is discussed.

  14. Bursting neurons and ultrasound avoidance in crickets.

    Science.gov (United States)

    Marsat, Gary; Pollack, Gerald S

    2012-01-01

    Decision making in invertebrates often relies on simple neural circuits composed of only a few identified neurons. The relative simplicity of these circuits makes it possible to identify the key computation and neural properties underlying decisions. In this review, we summarize recent research on the neural basis of ultrasound avoidance in crickets, a response that allows escape from echolocating bats. The key neural property shaping behavioral output is high-frequency bursting of an identified interneuron, AN2, which carries information about ultrasound stimuli from receptor neurons to the brain. AN2's spike train consists of clusters of spikes - bursts - that may be interspersed with isolated, non-burst spikes. AN2 firing is necessary and sufficient to trigger avoidance steering but only high-rate firing, such as occurs in bursts, evokes this response. AN2 bursts are therefore at the core of the computation involved in deciding whether or not to steer away from ultrasound. Bursts in AN2 are triggered by synaptic input from nearly synchronous bursts in ultrasound receptors. Thus the population response at the very first stage of sensory processing - the auditory receptor - already differentiates the features of the stimulus that will trigger a behavioral response from those that will not. Adaptation, both intrinsic to AN2 and within ultrasound receptors, scales the burst-generating features according to the stimulus statistics, thus filtering out background noise and ensuring that bursts occur selectively in response to salient peaks in ultrasound intensity. Furthermore AN2's sensitivity to ultrasound varies adaptively with predation pressure, through both developmental and evolutionary mechanisms. We discuss how this key relationship between bursting and the triggering of avoidance behavior is also observed in other invertebrate systems such as the avoidance of looming visual stimuli in locusts or heat avoidance in beetles.

  15. Bursting neurons and ultrasound avoidance in crickets

    Directory of Open Access Journals (Sweden)

    Gary eMarsat

    2012-07-01

    Full Text Available Decision making in invertebrates often relies on simple neural circuits composed of only a few identified neurons. The relative simplicity of these circuits makes it possible to identify the key computation and neural properties underlying decisions. In this review, we summarize recent research on the neural basis of ultrasound avoidance in crickets, a response that allows escape from echolocating bats. The key neural property shaping behavioral output is high-frequency bursting of an identified interneuron, AN2, which carries information about ultrasound stimuli from receptor neurons to the brain. AN2's spike train consists of clusters of spikes –bursts– that may be interspersed with isolated, non-burst spikes. AN2 firing is necessary and sufficient to trigger avoidance steering but only high-rate firing, such as occurs in bursts, evokes this response. AN2 bursts are therefore at the core of the computation involved in deciding whether or not to steer away from ultrasound. Bursts in AN2 are triggered by synaptic input from nearly synchronous bursts in ultrasound receptors. Thus the population response at the very first stage of sensory processing –the auditory receptor- already differentiates the features of the stimulus that will trigger a behavioral response from those that will not. Adaptation, both intrinsic to AN2 and within ultrasound receptors, scales the burst-generating features according to the stimulus statistics, thus filtering out background noise and ensuring that bursts occur selectively in response to salient peaks in ultrasound intensity. Furthermore AN2’s sensitivity to ultrasound varies adaptively with predation pressure, through both developmental and evolutionary mechanisms. We discuss how this key relationship between bursting and the triggering of avoidance behavior is also observed in other invertebrate systems such as the avoidance of looming visual stimuli in locusts or heat avoidance in beetles.

  16. Disruption avoidance through active magnetic feedback in tokamak plasmas

    Science.gov (United States)

    Paccagnella, Roberto; Zanca, Paolo; Yanovskiy, Vadim; Finotti, Claudio; Manduchi, Gabriele; Piron, Chiara; Carraro, Lorella; Franz, Paolo; RFX Team

    2014-10-01

    Disruptions avoidance and mitigation is a fundamental need for a fusion relevant tokamak. In this paper a new experimental approach for disruption avoidance using active magnetic feedback is presented. This scheme has been implemented and tested on the RFX-mod device operating as a circular tokamak. RFX-mod has a very complete system designed for active mode control that has been proved successful for the stabilization of the Resistive Wall Modes (RWMs). In particular the current driven 2/1 mode, unstable when the edge safety factor, qa, is around (or even less than) 2, has been shown to be fully and robustly stabilized. However, at values of qa (qa > 3), the control of the tearing 2/1 mode has been proved difficult. These results suggested the idea to prevent disruptions by suddenly lowering qa to values around 2 where the tearing 2/1 is converted to a RWM. Contrary to the universally accepted idea that the tokamaks should disrupt at low qa, we demonstrate that in presence of a well designed active control system, tokamak plasmas can be driven to low qa actively stabilized states avoiding plasma disruption with practically no loss of the plasma internal energy.

  17. Measuring Experiential Avoidance: Evidence toward Multidimensional Predictors of Trauma Sequelae

    Directory of Open Access Journals (Sweden)

    Meaghan Lewis

    2017-02-01

    Full Text Available The current study sought to investigate measurement discrepancies in self-report assessment of experiential avoidance (EA. Recent research indicates that EA may be more appropriately conceptualized as a multidimensional construct, operationally defined in terms of specific avoidance strategies. To test this notion, EA was measured using two self-report assessment instruments, the Acceptance and Action Questionnaire-II (AAQ-II and the Multidimensional Experiential Avoidance Questionnaire (MEAQ in a convenience sample of university students. Measurement differences across measures and unique contributions to prediction of posttraumatic stress symptoms (PTSS and engagement in problematic behaviors were evaluated. Both the AAQ-II and MEAQ were found to significantly mediate the effect of childhood trauma exposure on PTSS. However, when levels of PTSS were dummy coded into dichotomies of those with a likely PTSD diagnosis and those without, the MEAQ was a stronger predictor symptoms of those with a likely PTSD diagnosis than AAQ-II did. These results provide initial support for the discriminant validity of the MEAQ, which appears to be a more specific predictor of trauma-related symptoms.

  18. Seabird transfer of nutrients and trace elements from the north water polynya to land during the mid-holocene warm period, carey islands, northwest Greenland

    DEFF Research Database (Denmark)

    Outridge, Peter M.; Goodsite, Michael Evan; Bennike, Ole

    2016-01-01

    and N isotopic and trace element analyses of a peat core that represents ca. 2000 years of organic matter accumulation to examine the effect on trace elements and nutrients of a seabird colony that existed in northern Baffin Bay during the Holocene Thermal Maximum (ca. 8000-5000 yr BP). Although C and N......, in which guano markedly increased environmental Hg concentrations. It could be a consequence of Hg concentrations in Arctic marine food webs in the pre-industrial period that were an order of magnitude lower than those of today....

  19. A novel theory of experiential avoidance in generalized anxiety disorder: A review and synthesis of research supporting a contrast avoidance model of worry☆,☆☆

    Science.gov (United States)

    Newman, Michelle G.; Llera, Sandra J.

    2011-01-01

    An important emphasis of the literature on generalized anxiety disorder (GAD) has been to achieve a greater understanding of the function of emotion (e.g., avoidance, dysregulation) in the etiology and maintenance of this disorder. The purpose of the following paper is to propose a new way of conceptualizing emotional sequelae in GAD by detailing the Contrast Avoidance Model of Worry. In presenting this model, we review theory and data that led to our current position, which is that individuals with GAD are more sensitive to feeling emotionally vulnerable to unexpected negative events, and that worry (the key pathological feature of GAD) is employed to prolong and maintain a negative emotional state thereby avoiding an unexpected negative emotional shift, or contrast experience. We also discuss implications for treatment given the presence of a new target for emotional exposure techniques. Finally, we establish the Contrast Avoidance Model within the framework of extant theories and models of pathogenic processes of GAD. PMID:21334285

  20. 76 FR 30311 - Takes of Marine Mammals Incidental to Specified Activities; Seabird and Pinniped Research...

    Science.gov (United States)

    2011-05-25

    ... breed from late November to March. Females typically give birth to a single pup and attend the pup for... low numbers there currently (S. Allen, unpubl. data). Steller sea lions give birth in May through July.... The potential for incidental take related to the mark/recapture studies is very low as...

  1. Where to Forage in the Absence of Sea Ice? Bathymetry As a Key Factor for an Arctic Seabird.

    Directory of Open Access Journals (Sweden)

    Françoise Amélineau

    Full Text Available The earth is warming at an alarming rate, especially in the Arctic, where a marked decline in sea ice cover may have far-ranging consequences for endemic species. Little auks, endemic Arctic seabirds, are key bioindicators as they forage in the marginal ice zone and feed preferentially on lipid-rich Arctic copepods and ice-associated amphipods sensitive to the consequences of global warming. We tested how little auks cope with an ice-free foraging environment during the breeding season. To this end, we took advantage of natural variation in sea ice concentration along the east coast of Greenland. We compared foraging and diving behaviour, chick diet and growth and adult body condition between two years, in the presence versus nearby absence of sea ice in the vicinity of their breeding site. Moreover, we sampled zooplankton at sea when sea ice was absent to evaluate prey location and little auk dietary preferences. Little auks foraged in the same areas both years, irrespective of sea ice presence/concentration, and targeted the shelf break and the continental shelf. We confirmed that breeding little auks showed a clear preference for larger copepod species to feed their chick, but caught smaller copepods and nearly no ice-associated amphipod when sea ice was absent. Nevertheless, these dietary changes had no impact on chick growth and adult body condition. Our findings demonstrate the importance of bathymetry for profitable little auk foraging, whatever the sea-ice conditions. Our investigations, along with recent studies, also confirm more flexibility than previously predicted for this key species in a warming Arctic.

  2. Variation in Population Synchrony in a Multi-Species Seabird Community: Response to Changes in Predator Abundance.

    Directory of Open Access Journals (Sweden)

    Gail S Robertson

    in the environment and suggests that changes in predator abundance may differentially affect populations of sympatric seabird species.

  3. Variation in Population Synchrony in a Multi-Species Seabird Community: Response to Changes in Predator Abundance.

    Science.gov (United States)

    Robertson, Gail S; Bolton, Mark; Morrison, Paul; Monaghan, Pat

    2015-01-01

    environment and suggests that changes in predator abundance may differentially affect populations of sympatric seabird species.

  4. Variation in the Markers of Nutritional and Oxidative State in a Long-Lived Seabird: Associations with Age and Longevity.

    Science.gov (United States)

    Urvik, Janek; Meitern, Richard; Rattiste, Kalev; Saks, Lauri; Hõrak, Peeter; Sepp, Tuul

    2016-01-01

    Age-related declines in life-history traits have been widely observed in free-living animals. Several theories link senescence to oxidative stress. The aim of this study was to measure several widely used markers of oxidative and nutritional state in a long-lived seabird, the common gull (Larus canus), in order to assess the suitability of these markers for describing deterioration in physiological condition associated with chronological age and survival. Associations with longevity and individual consistency of these parameters over the years (repeatability) were also assessed. Senescence in fitness parameters was observed during the study period: in females, laying date and clutch mass were related to bird age in a curvilinear manner, with middle-aged birds breeding earlier and laying heavier eggs. The only parameter associated with aging processes was glutathione concentration in erythrocytes, which was lower in female birds with longer life spans. Of indexes of nutritional state, plasma triglyceride concentration showed a between-individual increase with age, suggesting selective mortality of birds with low levels. Additionally, total plasma protein levels of individual males increased with age. The mostly negative results of this study hint that the commonly used parameters of physiological condition and oxidative state used in this study do not adequately reflect an individual's long-term health condition. Alternatively, it is possible that in common gulls, senescence occurs in reproductive mechanisms but not in mechanisms responsible for maintaining an organism's redox balance, consistent with the idea that different aspects of an organism's physiological condition age at different rates. Significant interannual repeatability was detected in three plasma constituents-carotenoids, uric acid, and total protein-all of which can possibly be linked to variation in dietary habits.

  5. Where to Forage in the Absence of Sea Ice? Bathymetry As a Key Factor for an Arctic Seabird

    Science.gov (United States)

    Amélineau, Françoise; Grémillet, David; Bonnet, Delphine; Le Bot, Tangi; Fort, Jérôme

    2016-01-01

    The earth is warming at an alarming rate, especially in the Arctic, where a marked decline in sea ice cover may have far-ranging consequences for endemic species. Little auks, endemic Arctic seabirds, are key bioindicators as they forage in the marginal ice zone and feed preferentially on lipid-rich Arctic copepods and ice-associated amphipods sensitive to the consequences of global warming. We tested how little auks cope with an ice-free foraging environment during the breeding season. To this end, we took advantage of natural variation in sea ice concentration along the east coast of Greenland. We compared foraging and diving behaviour, chick diet and growth and adult body condition between two years, in the presence versus nearby absence of sea ice in the vicinity of their breeding site. Moreover, we sampled zooplankton at sea when sea ice was absent to evaluate prey location and little auk dietary preferences. Little auks foraged in the same areas both years, irrespective of sea ice presence/concentration, and targeted the shelf break and the continental shelf. We confirmed that breeding little auks showed a clear preference for larger copepod species to feed their chick, but caught smaller copepods and nearly no ice-associated amphipod when sea ice was absent. Nevertheless, these dietary changes had no impact on chick growth and adult body condition. Our findings demonstrate the importance of bathymetry for profitable little auk foraging, whatever the sea-ice conditions. Our investigations, along with recent studies, also confirm more flexibility than previously predicted for this key species in a warming Arctic. PMID:27438790

  6. Circulation of a Meaban-like virus in yellow-legged gulls and seabird ticks in the western Mediterranean basin.

    Directory of Open Access Journals (Sweden)

    Audrey Arnal

    Full Text Available In recent years, a number of zoonotic flaviviruses have emerged worldwide, and wild birds serve as their major reservoirs. Epidemiological surveys of bird populations at various geographical scales can clarify key aspects of the eco-epidemiology of these viruses. In this study, we aimed at exploring the presence of flaviviruses in the western Mediterranean by sampling breeding populations of the yellow-legged gull (Larus michahellis, a widely distributed, anthropophilic, and abundant seabird species. For 3 years, we sampled eggs from 19 breeding colonies in Spain, France, Algeria, and Tunisia. First, ELISAs were used to determine if the eggs contained antibodies against flaviviruses. Second, neutralization assays were used to identify the specific flaviviruses present. Finally, for colonies in which ELISA-positive eggs had been found, chick serum samples and potential vectors, culicid mosquitoes and soft ticks (Ornithodoros maritimus, were collected and analyzed using serology and PCR, respectively. The prevalence of flavivirus-specific antibodies in eggs was highly spatially heterogeneous. In northeastern Spain, on the Medes Islands and in the nearby village of L'Escala, 56% of eggs had antibodies against the flavivirus envelope protein, but were negative for neutralizing antibodies against three common flaviviruses: West Nile, Usutu, and tick-borne encephalitis viruses. Furthermore, little evidence of past flavivirus exposure was obtained for the other colonies. A subset of the Ornithodoros ticks from Medes screened for flaviviral RNA tested positive for a virus whose NS5 gene was 95% similar to that of Meaban virus, a flavivirus previously isolated from ticks of Larus argentatus in western France. All ELISA-positive samples subsequently tested positive for Meaban virus neutralizing antibodies. This study shows that gulls in the western Mediterranean Basin are exposed to a tick-borne Meaban-like virus, which underscores the need of exploring

  7. It is the time for oceanic seabirds: Tracking year-round distribution of gadfly petrels across the Atlantic Ocean

    Science.gov (United States)

    Ramos, Raul; Carlile, Nicholas; Madeiros, Jeremy; Ramirez, Ivan; Paiva, Vitor H.; Dinis, Herculano A.; Zino, Francis; Biscoito, Manuel; Leal, Gustavo R.; Bugoni, Leandro; Jodice, Patrick G.; Ryan, Peter G.; Gonzalez-Solis, Jacob

    2017-01-01

    AimAnthropogenic 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.LocationAtlantic Ocean.MethodsUsing 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.ResultsWe 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 conclusionsTracking 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

  8. Regular habitat switch as an important feeding strategy of an opportunistic seabird species at the interface between land and sea

    Science.gov (United States)

    Schwemmer, Philipp; Garthe, Stefan

    2008-03-01

    During deteriorated prey availability, purely pelagic, specialised seabird species have to alter their feeding strategy by extending foraging radii and/or time spent at sea or reducing feeding intervals of chicks. In contrast, more generalised species such as the opportunistic black-headed gull ( Larus ridibundus) breeding at the German North Sea coast, can be assumed to react on prey shortages by switching foraging habitats. The coastal zone of the German North Sea provides a rich habitat mosaic consisting of the offshore zone, tidal flats and terrestrial habitats. Thus, we expected distinct temporal and spatial patterns of habitat switch in accordance with prey availability and environmental constraints. We carried out ship-based and aerial surveys as well as dietary analyses and observations on flight activity. We found a significant switch from terrestrial to marine feeding sites both on a daily basis (related to tidal cycle) and over the whole breeding season. Most likely, the latter switch is the result of lower prey availability in the terrestrial habitats and an increasing quality (in terms of prey abundance and energy intake) of the marine area. While there was only moderate variability in habitat use among different years, we revealed significant differences in the diet of birds from different colonies. The high dietary plasticity and flexible feeding strategy, switching between terrestrial and marine prey is certainly of major importance for the success of an opportunistic avian top predator in a complex coastal zone. It is suggested that - compared to situations elsewhere - the number of breeding pairs of black-headed gulls in the German North Sea coast are still stable due to the switch of foraging habitats performed by individuals in this region.

  9. Defining ecologically relevant scales for spatial protection with long-term data on an endangered seabird and local prey availability.

    Science.gov (United States)

    Sherley, Richard B; Botha, Philna; Underhill, Les G; Ryan, Peter G; van Zyl, Danie; Cockcroft, Andrew C; Crawford, Robert J M; Dyer, Bruce M; Cook, Timothée R

    2017-03-01

    Human activities are important drivers of marine ecosystem functioning. However, separating the synergistic effects of fishing and environmental variability on the prey base of non-target predators is difficult, often because prey availability estimates on appropriate scales are lacking. Understanding how prey abundance at different spatial scales links to population change can help integrate the needs of non-target predators into fisheries management by defining ecologically-relevant areas for spatial protection. We investigated the local population response (number of breeders) of the bank cormorant Phalacrocorax neglectus, a range-restricted endangered seabird, to the availability of its prey, the heavily-fished west coast rock lobster Jasus lalandii. Using Bayesian state-space modeled cormorant counts at three colonies, 22 years of fisheries-independent data on local lobster abundance and generalized additive modeling, we determined the spatial-scale pertinent to these relationships in areas of differing lobster availability. Cormorant numbers responded positively to lobster availability in the intermediate and high abundance regions, but not where regime shifts and fishing pressure have depleted lobster stocks. The relationships were strongest at 20-30 km, greater than the cormorants' foraging range when breeding, and may have been influence by prey availability for non-breeding birds, prey switching or prey ecology. Our results highlight the importance of considering the scale of ecological relationships in marine spatial planning and suggest that designing spatial protection around focal species can benefit marine predators across their full life cycle. We propose the precautionary implementation of small-scale marine protected areas, followed by robust assessment and adaptive-management, to confirm population-level benefits for the cormorants, their prey and the wider ecosystem, without negative impacts on local fisheries. This article is protected by

  10. Meeting reproductive demands in a dynamic upwelling system: Foraging strategies of a pursuit-diving seabird, the marbled murrelet

    Science.gov (United States)

    Peery, M.Z.; Newman, S.H.; Storlazzi, C.D.; Beissinger, S.R.

    2009-01-01

    Seabirds maintain plasticity in their foraging behavior to cope with energy demands and foraging constraints that vary over the reproductive cycle, but behavioral studies comparing breeding and nonbreeding individuals are rare. Here we characterize how Marbled Murrelets (Brachyramphus marmoratus) adjust their foraging effort in response to changes in reproductive demands in an upwelling system in central California. We radio-marked 32 murrelets of known reproductive status (9 breeders, 12 potential breeders, and 11 nonbreeders) and estimated both foraging ranges and diving rates during the breeding season. Murrelets spent more time diving during upwelling than oceanographic relaxation, increased their foraging ranges as the duration of relaxation grew longer, and reduced their foraging ranges after transitions to upwelling. When not incubating, murrelets moved in a circadian pattern, spending nighttime hours resting near flyways used to reach nesting habitat and foraging during the daytime an average of 5.7 km (SD 6.7 km) from nighttime locations. Breeders foraged close to nesting habitat once they initiated nesting and nest attendance was at a maximum, and then resumed traveling longer distances following the completion of nesting. Nonbreeders had similar nighttime and daytime distributions and tended to be located farther from inland flyways. Breeders increased the amount of time they spent diving by 71-73% when they had an active nest by increasing the number of dives rather than by increasing the frequency of anaerobiosis. Thus, to meet reproductive demands during nesting, murrelets adopted a combined strategy of reducing energy expended commuting to foraging sites and increasing aerobic dive rates. ?? 2009 by The Cooper Ornithological Society. All rights reserved.

  11. Status report of seabird surveys at Horns Rev, 2000-2001

    Energy Technology Data Exchange (ETDEWEB)

    Kjaer Christensen, T.; Clausager, I.; Krag Petersen, I. [NERI, Dept. of Coastal Zone Ecology, Roskilde (Denmark)

    2002-07-01

    The present report presents the results of three bird surveys conducted in the Horns Rev area during the second half of 2001. Due to poor weather conditions in December 2001, the last survey was, however, performed on 7 January 2002. The surveys are part of the base-line investigations of birds performed in relation to the proposed construction of an offshore wind farm at Horns Rev in the Danish part of the North Sea ca 14 km southwest of Blaevandshuk. The results of the surveys during August 2001 - January 2002 are presented together with the results obtained during the period August 2000 - April 2001, and are also compared to results obtained during the period August 1999 - April 2000. Based on the distribution of the most abundant bird species recorded during 16 aerial surveys performed during August 1999 - January 2002, there were no indications that the wind farm area was of any particular importance to the birds' exploitation of the Horns Rev area. Fish-eating species like divers, gannet, terns, auks and gulls generally showed scattered and variable distributions, mainly occurring in the areas north and south of Horns Rev, and with low numbers on the reef proper and within the planned wind farm area. The distribution of benthic foraging species, eider and common Scoter, showed that they mainly exploited the coastal parts of the area off Blaevandshuk and Skallingen, although common scoter was found in relatively high numbers on the southeast slopes of the Horns Rev and within the wind farm area in the April 2001 survey. Common scoters occurred in very high numbers in January 2002. This was probably related to increased immigration of birds from the inner Danish waters during a cold period in late December 2001. Preference analyses of bird exploitation of the Horns Rev area showed that if the birds completely avoid the wind farm area after erection of the wind turbines, this will affect less than 1% of the various species, except divers where 1.58% will be

  12. Tomographic patient registration and conformal avoidance tomotherapy

    Science.gov (United States)

    Aldridge, Jennifer Stacy

    Development of tomotherapy has led to the emergence of several processes, providing the basis for many unique investigative opportunities. These processes include setup verification, tomographic verification, megavoltage dose reconstruction, and conformal avoidance tomotherapy. Setup verification and conformal avoidance tomotherapy, in particular, are two closely intertwined matters. In order to avoid critical structures located within or adjacent to indistinct tumor regions, accurate patient positioning from fraction to fraction must be ensured. With tomographic patient registration, a higher level of assurance is offered than with traditional positioning methods. Translational and rotational offsets are calculated directly from projection data using cross- correlation or fast Fourier transforms. Experiments assessing the algorithm's ability to calculate individual offsets were conducted using the University of Wisconsin's Tomotherapy Benchtop. These experiments indicate statistical errors within +/-1 mm for offsets up to approximately 20 mm, with maximum offset errors of about +/-2 mm for displacements up to 35 mm. The angular offset component is within +/-2°. To evaluate the registration process as a whole, experimental results from a few multi-parameter examples are also analyzed. With the development of tomographic patient registration in projection space, efforts to promote further sparing of critical structures are justified. Conformal avoidance tomotherapy has as its objective to treat an indistinct tumor region while conformally avoiding any normal critical structures in that region. To demonstrate the advantages of conformal avoidance tomotherapy, conventional and tomotherapy treatments are contrasted for both nasopharyngeal and breast carcinoma cases. For initial research efforts, computed tomography data sets of a human male and female were obtained via the ``Visible Human Project''. Since these data sets are on the order of hundreds of megabytes, both

  13. Construction dispute research conceptualisation, avoidance and resolution

    CERN Document Server

    2014-01-01

    There are three specific purposes of Construction Dispute Research. First, this volume aims to summarise studies on construction dispute. Second, apart from the theoretical constructs, where appropriate empirical tests are also included. This approach serves to go beyond the commonly used anecdotal approach for the subject matters. Third, it is the sincere hope of the authors that this book will help shaping research agenda of construction dispute.  The studies are mostly framed from a management perspective drawing on methods and concepts in contract law, economics, psychology and management science.   The book has twenty chapters that are arranged in four parts covering conceptualisation, avoidance, negotiation and mediation. Part 1 is devoted for dispute conceptualisation. A building is only as strong as its foundation. Thus it is no better start to study construction dispute by conceptualisation. The theme of Part 2 is dispute avoidance. The conventional wisdom of ‘prevention is better than cure’ se...

  14. How to avoid deferred-compensation troubles.

    Science.gov (United States)

    Freeman, Todd I

    2005-06-01

    Executive compensation packages have long included stock options and deferred compensation plans in order to compete for talent. Last year, Congress passed a law in response to the Enron debacle, in which executives were perceived to be protecting their deferred compensation at the expense of employees, creditors, and investors. The new law is designed to protect companies and their shareholders from being raided by the very executives that guided the company to financial ruin. Physicians who are part owners of medical practices need to know about the changes in the law regarding deferred compensation and how to avoid costly tax penalties. This article discusses how the changes affect medical practices as well as steps physician-owned clinics can take to avoid the risk of penalty, such as freezing deferred compensation and creating a new deferred compensation plan.

  15. Optical Flow based Robot Obstacle Avoidance

    Directory of Open Access Journals (Sweden)

    Kahlouche Souhila

    2008-11-01

    Full Text Available In this paper we try to develop an algorithm for visual obstacle avoidance of autonomous mobile robot. The input of the algorithm is an image sequence grabbed by an embedded camera on the B21r robot in motion. Then, the optical flow information is extracted from the image sequence in order to be used in the navigation algorithm. The optical flow provides very important information about the robot environment, like: the obstacles disposition, the robot heading, the time to collision and the depth. The strategy consists in balancing the amount of left and right side flow to avoid obstacles, this technique allows robot navigation without any collision with obstacles. The robustness of the algorithm will be showed by some examples.

  16. Information Dilemmas and Blame-Avoidance Strategies

    DEFF Research Database (Denmark)

    Erik, Baekkeskov; Rubin, Olivier

    2016-01-01

    China and other authoritarian states notoriously keep mum about disasters. Yet two recent but dissimilar Chinese responses to infectious disease epidemics show that authoritarian crisis management can shift from secrecy to openness. China maintained prolonged secrecy during 2003 SARS, yet was ope...... in place public health specialists and institutions as responsible for H1N1 information and responses, thereby insulating the top-tier leadership.......China and other authoritarian states notoriously keep mum about disasters. Yet two recent but dissimilar Chinese responses to infectious disease epidemics show that authoritarian crisis management can shift from secrecy to openness. China maintained prolonged secrecy during 2003 SARS, yet was open...... from day one about 2009 H1N1 flu. To explore why, this article links crisis information dilemmas to blame avoidance concepts from democratic political theories. We argue that greater Chinese transparency about infectious disease response reflects evolution in blame avoidance, from heavy reliance...

  17. Acute carbon dioxide avoidance in Caenorhabditis elegans

    OpenAIRE

    Hallem, Elissa A.; Sternberg, Paul W.

    2008-01-01

    Carbon dioxide is produced as a by-product of cellular respiration by all aerobic organisms and thus serves for many animals as an important indicator of food, mates, and predators. However, whether free-living terrestrial nematodes such as Caenorhabditis elegans respond to CO2 was unclear. We have demonstrated that adult C. elegans display an acute avoidance response upon exposure to CO2 that is characterized by the cessation of forward movement and the rapid initiation of backward movement....

  18. Potentially Avoidable Peripartum Hysterectomies in Denmark

    DEFF Research Database (Denmark)

    Colmorn, Lotte Berdiin; Krebs, Lone; Langhoff-Roos, Jens

    2016-01-01

    to minimize the number of unnecessary peripartum hysterectomies, obstetricians and anesthesiologists should investigate individual cases by structured clinical audit, and disseminate and discuss the results for educational purposes. An international collaboration is warranted to strengthen our recommendations......OBJECTIVE: To audit the clinical management preceding peripartum hysterectomy and evaluate if peripartum hysterectomies are potentially avoidable and by which means. MATERIAL AND METHODS: We developed a structured audit form based on explicit criteria for the minimal mandatory management...

  19. Robot maps, robot moves, robot avoids

    OpenAIRE

    Farrugia, Claire

    2014-01-01

    Robotics is a cornerstone for this century’s innovations. From robot nurses to your own personal assistant, most robots need to know: ‘where is it?’ ‘Where should it go?’ And ‘how to get there?’ Without answers to these questions a robot cannot do much. http://www.um.edu.mt/think/robot-maps-robot-moves-robot-avoids/

  20. Robot maps, robot moves, robot avoids

    OpenAIRE

    Farrugia, Claire; Duca, Edward

    2014-01-01

    Robotics is a cornerstone for this century’s innovations. From robot nurses to your own personal assistant, most robots need to know: ‘where is it?’ ‘Where should it go?’ And ‘how to get there?’ Without answers to these questions a robot cannot do much. http://www.um.edu.mt/think/robot-maps-robot-moves-robot-avoids/

  1. [Mortality by avoidable causes in preschool children].

    Science.gov (United States)

    Lurán, Albenia; López, Elizabeth; Pinilla, Consuelo; Sierra, Pedro

    2009-03-01

    The infant-mortality rate in children aged less than five is an indicator of the general state of health of a population and directly reflects the quality of life and the level of socio-economic development of a country. Avoidable mortality was assessed in preschool children as a reflection of Colombia quality of life and socio-economic development. Mortality trends were analyzed in preschool children aged less than five throughout Colombia during a 20-year period from 1985-2004, and focused on mortality causes that were considered avoidable. This was a descriptive, retrospective study; the sources of information were Departamento Administrativo Nacional de Estadística records of deaths and population projections 1985-2004. Mortality rate due to avoidable causes was the statistical indicator. In children aged less than one, the reducible mortality due to "early diagnosis and medical treatment" occupied the first place amongst causes for every year of the study period and accounted for more than 50% of recorded deaths. In children aged 1 to 4, the category "other important reducible causes" was associated with 40% of recorded deaths-deaths due mainly to respiratory diseases. Over the 20-year period, the avoidable mortality rate decreased by 34% in children aged less than one, in children 1-4, it decreased by 23%. Although the infant-mortality rate in preschool children was reduced, the decrease was small, from 80% to 77%. The situation requires more analysis with respect to strategies in public health, particularly concerning preventable diseases of the infancy.

  2. Potentially avoidable peripartum hysterectomies in Denmark

    DEFF Research Database (Denmark)

    Colmorn, Lotte Berdiin; Krebs, Lone; Langhoff-Roos, Jens

    2016-01-01

    to minimize the number of unnecessary peripartum hysterectomies, obstetricians and anesthesiologists should investigate individual cases by structured clinical audit, and disseminate and discuss the results for educational purposes. An international collaboration is warranted to strengthen our recommendations......Objective: To audit the clinical management preceding peripartum hysterectomy and evaluate if peripartum hysterectomies are potentially avoidable and by which means. Material and Methods: We developed a structured audit form based on explicit criteria for the minimal mandatory management...

  3. Tax avoidance: Definition and prevention issues

    Directory of Open Access Journals (Sweden)

    Anđelković Mileva

    2014-01-01

    Full Text Available The problem of resolving issues pertaining to tax avoidance, and particularly its aggressive forms, has been the focal point of discussion among tax scholars which is increasingly gaining attention of politicians alike. As opposed to tax evasion (which is illegal, the phenomenon of tax avoidance calls for careful consideration of state fiscal interests and a highly precise demarcation of the thin line between the acceptable and unacceptable conduct. In many contemporary states, tax avoidance (which implies a formal behaviour of tax payers within the limits of tax legislation but contrary to the tax regulation objectives is declared to be illegitimate. State authorities do not want to tolerate such activity, which results in tax payers' reduction or avoidance of tax liabilities. We should also bear in mind that all tax payers have the tax planning option at their disposal, by means of which they make sure that they do not pay more tax than they are legally obliged to. However, in case they skilfully use the tax regulation flaws and loopholes for the sole purpose of tax evasion, and/or resort to misrepresentation and deceptive constructs, they are considered to be exceeding the limits of acceptable tax behaviour. In comparison to the specific anti-abuse measures which have been built into some national tax legislations, there is a growing number of states that introduce the general anti-abuse legislations, which is based on judicial doctrines or statutory legislation. Yet, there is a notable difference among the envisaged anti-abuse measures depending on whether the national legislation is based on the Anglo-American or European-Continental legal system. The efficiency of applying these general anti-abuse rules in taxation largely rests on their interpretation as well as on their relationship with the principle of legality.

  4. Airborne Collision Detection and Avoidance for Small UAS Sense and Avoid Systems

    Science.gov (United States)

    Sahawneh, Laith Rasmi

    The increasing demand to integrate unmanned aircraft systems (UAS) into the national airspace is motivated by the rapid growth of the UAS industry, especially small UAS weighing less than 55 pounds. Their use however has been limited by the Federal Aviation Administration regulations due to collision risk they pose, safety and regulatory concerns. Therefore, before civil aviation authorities can approve routine UAS flight operations, UAS must be equipped with sense-and-avoid technology comparable to the see-and-avoid requirements for manned aircraft. The sense-and-avoid problem includes several important aspects including regulatory and system-level requirements, design specifications and performance standards, intruder detecting and tracking, collision risk assessment, and finally path planning and collision avoidance. In this dissertation, our primary focus is on developing an collision detection, risk assessment and avoidance framework that is computationally affordable and suitable to run on-board small UAS. To begin with, we address the minimum sensing range for the sense-and-avoid (SAA) system. We present an approximate close form analytical solution to compute the minimum sensing range to safely avoid an imminent collision. The approach is then demonstrated using a radar sensor prototype that achieves the required minimum sensing range. In the area of collision risk assessment and collision prediction, we present two approaches to estimate the collision risk of an encounter scenario. The first is a deterministic approach similar to those been developed for Traffic Alert and Collision Avoidance (TCAS) in manned aviation. We extend the approach to account for uncertainties of state estimates by deriving an analytic expression to propagate the error variance using Taylor series approximation. To address unanticipated intruders maneuvers, we propose an innovative probabilistic approach to quantify likely intruder trajectories and estimate the probability of

  5. An information theoretic approach for generating an aircraft avoidance Markov Decision Process

    Science.gov (United States)

    Weinert, Andrew J.

    Developing a collision avoidance system that can meet safety standards required of commercial aviation is challenging. A dynamic programming approach to collision avoidance has been developed to optimize and generate logics that are robust to the complex dynamics of the national airspace. The current approach represents the aircraft avoidance problem as Markov Decision Processes and independently optimizes a horizontal and vertical maneuver avoidance logics. This is a result of the current memory requirements for each logic, simply combining the logics will result in a significantly larger representation. The "curse of dimensionality" makes it computationally inefficient and unfeasible to optimize this larger representation. However, existing and future collision avoidance systems have mostly defined the decision process by hand. In response, a simulation-based framework was built to better understand how each potential state quantifies the aircraft avoidance problem with regards to safety and operational components. The framework leverages recent advances in signals processing and database, while enabling the highest fidelity analysis of Monte Carlo aircraft encounter simulations to date. This framework enabled the calculation of how well each state of the decision process quantifies the collision risk and the associated memory requirements. Using this analysis, a collision avoidance logic that leverages both horizontal and vertical actions was built and optimized using this simulation based approach.

  6. Acute carbon dioxide avoidance in Caenorhabditis elegans.

    Science.gov (United States)

    Hallem, Elissa A; Sternberg, Paul W

    2008-06-10

    Carbon dioxide is produced as a by-product of cellular respiration by all aerobic organisms and thus serves for many animals as an important indicator of food, mates, and predators. However, whether free-living terrestrial nematodes such as Caenorhabditis elegans respond to CO2 was unclear. We have demonstrated that adult C. elegans display an acute avoidance response upon exposure to CO2 that is characterized by the cessation of forward movement and the rapid initiation of backward movement. This response is mediated by a cGMP signaling pathway that includes the cGMP-gated heteromeric channel TAX-2/TAX-4. CO2 avoidance is modulated by multiple signaling molecules, including the neuropeptide Y receptor NPR-1 and the calcineurin subunits TAX-6 and CNB-1. Nutritional status also modulates CO2 responsiveness via the insulin and TGFbeta signaling pathways. CO2 response is mediated by a neural circuit that includes the BAG neurons, a pair of sensory neurons of previously unknown function. TAX-2/TAX-4 function in the BAG neurons to mediate acute CO2 avoidance. Our results demonstrate that C. elegans senses and responds to CO2 using multiple signaling pathways and a neural network that includes the BAG neurons and that this response is modulated by the physiological state of the worm.

  7. Traffic jam driving with NMV avoidance

    Science.gov (United States)

    Milanés, Vicente; Alonso, Luciano; Villagrá, Jorge; Godoy, Jorge; de Pedro, Teresa; Oria, Juan P.

    2012-08-01

    In recent years, the development of advanced driver assistance systems (ADAS) - mainly based on lidar and cameras - has considerably improved the safety of driving in urban environments. These systems provide warning signals for the driver in the case that any unexpected traffic circumstance is detected. The next step is to develop systems capable not only of warning the driver but also of taking over control of the car to avoid a potential collision. In the present communication, a system capable of autonomously avoiding collisions in traffic jam situations is presented. First, a perception system was developed for urban situations—in which not only vehicles have to be considered, but also pedestrians and other non-motor-vehicles (NMV). It comprises a differential global positioning system (DGPS) and wireless communication for vehicle detection, and an ultrasound sensor for NMV detection. Then, the vehicle's actuators - brake and throttle pedals - were modified to permit autonomous control. Finally, a fuzzy logic controller was implemented capable of analyzing the information provided by the perception system and of sending control commands to the vehicle's actuators so as to avoid accidents. The feasibility of the integrated system was tested by mounting it in a commercial vehicle, with the results being encouraging.

  8. How does a cyclist avoid obstacles?

    Science.gov (United States)

    Miyadait, Masayuki; Uetake, Teruo; Shimoda, Masahiro

    2012-12-01

    The purpose of this research is to examine the ways bicycles swerve off sidewalks onto roads under various conditions. Seven students, five males and two females participated in an experiment on a road with a 100-cm wide sidewalk. Footage of each participant on a bicycle evading obstacles such as a utility pole and pedestrian were taken with a video camera, while a front-wheel view of the path taken by the bicycle was recorded simultaneously with a digital camera. Twelve experimental conditions were used for each participant, consisting of all the combinations of (1) three obstacle types, (2) the side (left or right) to which the bicycle went to avoid the obstacle, and (3) two weather conditions. Based on the two recorded scenes, the path was then analyzed from the viewpoint of how the bicycle swerved to avoid hitting the obstacle. We found that the conditions of riding a bicycle with an umbrella caused a larger swerve to avoid the obstacle than those conditions when the rider did not have an umbrella. In particular, the condition in which the obstacle was a pedestrian who also had an umbrella caused the largest swerve. Furthermore, the distance required to become aligned with the sidewalk when the obstacle was a pedestrian walking toward the cyclist was longer than that for other obstacles. The swerve width data showed interesting results, including a tendency for swerve width to be wider when the obstacle was a utility pole compared with other obstacles.

  9. Training Approach-Avoidance of Smiling Faces Affects Emotional Vulnerability in Socially Anxious Individuals

    Directory of Open Access Journals (Sweden)

    Mike eRinck

    2013-08-01

    Full Text Available Previous research revealed an automatic behavioral bias in high socially anxious individuals (HSAs: Although their explicit evaluations of smiling faces are positive, they show automatic avoidance of these faces. This is reflected by faster pushing than pulling of smiling faces in an Approach-Avoidance Task (AAT; Heuer, Rinck, & Becker, 2007. The current study addressed the causal role of this avoidance bias for social anxiety. To this end, we used the AAT to train HSAs, either to approach smiling faces or to avoid them. We examined whether such an AAT training could change HSAs’ automatic avoidance tendencies, and if yes, whether AAT effects would generalize to a new approach task with new facial stimuli, and to mood and anxiety in a social threat situation (a video-recorded self-presentation. We found that HSAs trained to approach smiling faces did indeed approach female faces faster after the training than HSAs trained to avoid smiling faces. Moreover, approach-faces training reduced emotional vulnerability: It led to more positive mood and lower anxiety after the self-presentation than avoid-faces training. These results suggest that automatic approach-avoidance tendencies have a causal role in social anxiety, and that they can be modified by a simple computerized training. This may open new avenues in the therapy of social phobia.

  10. Obstacle Avoidance of mobile robot using PSO based Neuro Fuzzy Technique

    Directory of Open Access Journals (Sweden)

    Sourav Dutta

    2010-03-01

    Full Text Available Navigation and obstacle avoidance are veryimportant issues for the successful use of an autonomous mobilerobot. To allow the robot to move between its current and finalconfigurations without any collision within the surroundingenvironment, motion planning needs much treatment. Thus togenerate collision free path it should have proper motionplanning as well as obstacle avoidance scheme. This work mainlydeals with the obstacle avoidance of a wheeled mobile robot instructured environment by using PSO based neuro-fuzzyapproach. Here three layer neural network with PSO is used aslearning algorithm to determine the optimal collision-free path.

  11. Rapid Assessment of Avoidable Blindness in India.

    Directory of Open Access Journals (Sweden)

    John Neena

    Full Text Available BACKGROUND: Rapid assessment of avoidable blindness provides valid estimates in a short period of time to assess the magnitude and causes of avoidable blindness. The study determined magnitude and causes of avoidable blindness in India in 2007 among the 50+ population. METHODS AND FINDINGS: Sixteen randomly selected districts where blindness surveys were undertaken 7 to 10 years earlier were identified for a follow up survey. Stratified cluster sampling was used and 25 clusters (20 rural and 5 urban were randomly picked in each district.. After a random start, 100 individuals aged 50+ were enumerated and examined sequentially in each cluster. All those with presenting vision = 50 years were enumerated, and 94.7% examined. Based on presenting vision,, 4.4% (95% Confidence Interval[CI]: 4.1,4.8 were severely visually impaired (vision<6/60 to 3/60 in the better eye and 3.6% (95% CI: 3.3,3.9 were blind (vision<3/60 in the better eye. Prevalence of low vision (<6/18 to 6/60 in the better eye was 16.8% (95% CI: 16.0,17.5. Prevalence of blindness and severe visual impairment (<6/60 in the better eye was higher among rural residents (8.2%; 95% CI: 7.9,8.6 compared to urban (7.1%; 95% CI: 5.0, 9.2, among females (9.2%; 95% CI: 8.6,9.8 compared to males (6.5%; 95% CI: 6.0,7.1 and people above 70 years (20.6%; 95% CI: 19.1,22.0 compared to people aged 50-54 years (1.3%; 95% CI: 1.1,1.6. Of all blindness, 88.2% was avoidable. of which 81.9% was due to cataract and 7.1% to uncorrected refractive errors/uncorrected aphakia. CONCLUSIONS: Cataract and refractive errors are major causes of blindness and low vision and control strategies should prioritize them. Most blindness and low vision burden is avoidable.

  12. See-and-Avoid Collision Avoidance Using ADS-B Signal and Radar Sensing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — IAI proposes an innovative collision avoidance radar and communication technology to detect and track both cooperative and non-cooperative targets. The system...

  13. The relationship between pink salmon biomass and the body condition of short-tailed shearwaters in the Bering Sea: can fish compete with seabirds?

    Science.gov (United States)

    Toge, Kanako; Yamashita, Rei; Kazama, Kentaro; Fukuwaka, Masaaki; Yamamura, Orio; Watanuki, Yutaka

    2011-09-07

    Seabirds and large fishes are important top predators in marine ecosystems, but few studies have explored the potential for competition between these groups. This study investigates the relationship between an observed biennial change of pink salmon (Oncorhynchus gorbuscha) biomass in the central Bering Sea (23 times greater in odd-numbered than in even-numbered years) and the body condition and diet of the short-tailed shearwater (Puffinus tenuirostris) that spends the post-breeding season there. Samples were collected with research gill nets over seven summers. Both species feed on krill, small fishes and squid. Although the mean pink salmon catch per unit effort (in mass) over the study region was not related significantly with shearwater's stomach content mass or prey composition, the pink salmon biomass showed a negative and significant relationship with the shearwater's body mass and liver mass (proxies of energy reserve). We interpret these results as evidence that fishes can negatively affect mean prey intake of seabirds if they feed on a shared prey in the pelagic ecosystem.

  14. Avoiding unseen obstacles: Subcortical vision is not sufficient to maintain normal obstacle avoidance behaviour during reaching.

    Science.gov (United States)

    Ross, Alasdair I; Schenk, Thomas; Billino, Jutta; Macleod, Mary J; Hesse, Constanze

    2016-10-03

    Previous research found that a patient with cortical blindness (homonymous hemianopia) was able to successfully avoid an obstacle placed in his blind field, despite reporting no conscious awareness of it [Striemer, C. L., Chapman, C. S., & Goodale, M. A., 2009, PNAS, 106(37), 15996-16001]. This finding led to the suggestion that dorsal stream areas, that are assumed to mediate obstacle avoidance behaviour, may obtain their visual input primarily from subcortical pathways. Hence, it was suggested that normal obstacle avoidance behaviour can proceed without input from the primary visual cortex. Here we tried to replicate this finding in a group of patients (N = 6) that suffered from highly circumscribed lesions in the occipital lobe (including V1) that spared the subcortical structures that have been associated with action-blindsight. We also tested if obstacle avoidance behaviour differs depending on whether obstacles are placed only in the blind field or in both the blind and intact visual field of the patients simultaneously. As expected, all patients successfully avoided obstacles placed in their intact visual field. However, none of them showed reliable avoidance behaviour - as indicated by adjustments in the hand trajectory in response to obstacle position - for obstacles placed in their blind visual field. The effects were not dependent on whether one or two obstacles were present. These findings suggest that behaviour in complex visuomotor tasks relies on visual input from occipital areas.

  15. The influence of mastery-avoidance goals on performance improvement

    NARCIS (Netherlands)

    Van Yperen, Nico W.; Elliot, Andrew J.; Anseel, Frederik

    2009-01-01

    Two experiments focused on examining the influence of mastery-avoidance goals on performance improvement, and more specifically, on mastery-avoidance goals grounded in an intrapersonal standard. That is, herein, mastery-avoidance goals entail striving to avoid doing worse than one has done before. B

  16. Convective Weather Avoidance with Uncertain Weather Forecasts

    Science.gov (United States)

    Karahan, Sinan; Windhorst, Robert D.

    2009-01-01

    Convective weather events have a disruptive impact on air traffic both in terminal area and in en-route airspaces. In order to make sure that the national air transportation system is safe and efficient, it is essential to respond to convective weather events effectively. Traffic flow control initiatives in response to convective weather include ground delay, airborne delay, miles-in-trail restrictions as well as tactical and strategic rerouting. The rerouting initiatives can potentially increase traffic density and complexity in regions neighboring the convective weather activity. There is a need to perform rerouting in an intelligent and efficient way such that the disruptive effects of rerouting are minimized. An important area of research is to study the interaction of in-flight rerouting with traffic congestion or complexity and developing methods that quantitatively measure this interaction. Furthermore, it is necessary to find rerouting solutions that account for uncertainties in weather forecasts. These are important steps toward managing complexity during rerouting operations, and the paper is motivated by these research questions. An automated system is developed for rerouting air traffic in order to avoid convective weather regions during the 20- minute - 2-hour time horizon. Such a system is envisioned to work in concert with separation assurance (0 - 20-minute time horizon), and longer term air traffic management (2-hours and beyond) to provide a more comprehensive solution to complexity and safety management. In this study, weather is dynamic and uncertain; it is represented as regions of airspace that pilots are likely to avoid. Algorithms are implemented in an air traffic simulation environment to support the research study. The algorithms used are deterministic but periodically revise reroutes to account for weather forecast updates. In contrast to previous studies, in this study convective weather is represented as regions of airspace that pilots

  17. The global cost of eliminating avoidable blindness

    Directory of Open Access Journals (Sweden)

    Kirsten L Armstrong

    2012-01-01

    Full Text Available Aims : To complete an initial estimate of the global cost of eliminating avoidable blindness, including the investment required to build ongoing primary and secondary health care systems, as well as to eliminate the ′backlog′ of avoidable blindness. This analysis also seeks to understand and articulate where key data limitations lie. Materials and Methods : Data were collected in line with a global estimation approach, including separate costing frameworks for the primary and secondary care sectors, and the treatment of backlog. Results : The global direct health cost to eliminate avoidable blindness over a 10-year period from 2011 to 2020 is estimated at $632 billion per year (2009 US$. As countries already spend $592 billion per annum on eye health, this represents additional investment of $397.8 billion over 10 years, which is $40 billion per year or $5.80 per person for each year between 2010 and 2020. This is concentrated in high-income nations, which require 68% of the investment but comprise 16% of the world′s inhabitants. For all other regions, the additional investment required is $127 billion. Conclusions : This costing estimate has identified that low- and middle-income countries require less than half the additional investment compared with high-income nations. Low- and middle-income countries comprise the greater investment proportion in secondary care whereas high-income countries require the majority of investment into the primary sector. However, there is a need to improve sector data. Investment in better data will have positive flow-on effects for the eye health sector.

  18. Arctic warming: nonlinear impacts of sea-ice and glacier melt on seabird foraging.

    Science.gov (United States)

    Grémillet, David; Fort, Jérôme; Amélineau, Françoise; Zakharova, Elena; Le Bot, Tangi; Sala, Enric; Gavrilo, Maria

    2015-03-01

    Arctic climate change has profound impacts on the cryosphere, notably via shrinking sea-ice cover and retreating glaciers, and it is essential to evaluate and forecast the ecological consequences of such changes. We studied zooplankton-feeding little auks (Alle alle), a key sentinel species of the Arctic, at their northernmost breeding site in Franz-Josef Land (80°N), Russian Arctic. We tested the hypothesis that little auks still benefit from pristine arctic environmental conditions in this remote area. To this end, we analysed remote sensing data on sea-ice and coastal glacier dynamics collected in our study area across 1979-2013. Further, we recorded little auk foraging behaviour using miniature electronic tags attached to the birds in the summer of 2013, and compared it with similar data collected at three localities across the Atlantic Arctic. We also compared current and historical data on Franz-Josef Land little auk diet, morphometrics and chick growth curves. Our analyses reveal that summer sea-ice retreated markedly during the last decade, leaving the Franz-Josef Land archipelago virtually sea-ice free each summer since 2005. This had a profound impact on little auk foraging, which lost their sea-ice-associated prey. Concomitantly, large coastal glaciers retreated rapidly, releasing large volumes of melt water. Zooplankton is stunned by cold and osmotic shock at the boundary between glacier melt and coastal waters, creating new foraging hotspots for little auks. Birds therefore switched from foraging at distant ice-edge localities, to highly profitable feeding at glacier melt-water fronts within <5 km of their breeding site. Through this behavioural plasticity, little auks maintained their chick growth rates, but showed a 4% decrease in adult body mass. Our study demonstrates that arctic cryosphere changes may have antagonistic ecological consequences on coastal trophic flow. Such nonlinear responses complicate modelling exercises of current and future

  19. Wireless vehicular networks for car collision avoidance

    CERN Document Server

    2013-01-01

    Wireless Vehicular Networks for Car Collision Avoidance focuses on the development of the ITS (Intelligent Transportation Systems) in order to minimize vehicular accidents. The book presents and analyses a range of concrete accident scenarios while examining the causes of vehicular collision and proposing countermeasures based on wireless vehicular networks. The book also describes the vehicular network standards and quality of service mechanisms focusing on improving critical dissemination of safety information. With recommendations on techniques and protocols to consider when improving road safety policies in order to minimize crashes and collision risks.

  20. Contact Dermatitis, Patch Testing, and Allergen Avoidance.

    Science.gov (United States)

    Burkemper, Nicole M

    2015-01-01

    In patients presenting with a complaint of rash, contact dermatitis is often the underlying diagnosis making it an entity with which health care providers should be familiar. Contact dermatitis can be divided into irritant contact dermatitis and allergic contact dermatitis. In a patient suspected of having allergic contact dermatitis, patch testing can be done to identify specific allergens. Education focused on allergen avoidance and safe products is an integral part of treatment for the contact dermatitis patient. Knowledge of the most common allergens is helpful for clinicians to be able to provide this education.