Now showing items 1-15 of 15

    • Circumpolar dynamics of a marine top-predator track ocean warming rates. 

      Descamps, Sebastian; Anker-Nilssen, Tycho; Barrett, Robert T.; Irons, D.; Merkel, Flemming; Robertson, Gregory J.; Yoccoz, Nigel Gilles; Mallory, Mark L.; Montevecchi, William A.; Boertmann, D.; Artukhin, Yuri; Christensen-Dalsgaard, Signe; Erikstad, Kjell E.; Gilchrist, H. Grant; Labansen, Aili; Lorentsen, Svein Håkon; Mosbech, Anders; Olsen, Bergur; Petersen, Aevar; Rail, Jean-Francois; Renner, Heather M.; Strøm, H.; Systad, Geir Helge; Wilhelm, Sabina I.; Zelenskaya, Larisa (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-07)
      Global warming is a nonlinear process, and temperature may increase in a stepwise manner. Periods of abrupt warming can trigger persistent changes in the state of ecosystems, also called regime shifts. The responses of organisms to abrupt warming and associated regime shifts can be unlike responses to periods of slow or moderate change. Understanding of nonlinearity in the biological responses to ...
    • The decline of Norwegian kittiwake populations: modelling the role of ocean warming. 

      Sandvik, Hanno; Reiertsen, Tone K.; Erikstad, Kjell Einar; Anker-Nilssen, Tycho; Barrett, Robert T.; Lorentsen, Svein-Håkon; Systad, Geir Helge; Myksvoll, Mari Skuggedal (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      The black-legged kittiwake Rissa tridactyla is a pelagic seabird whose population has recently declined in most parts of the North Atlantic and which is red-listed in most bordering countries. To investigate a possible cause for this decline, we analysed the population dynamics of 5 kittiwake colonies along the Norwegian coast, ranging from 62° to 71° N, over the last 20 to 35 yr. By quantifying the ...
    • Global phenological insensitivity to shifting ocean temperatures among seabirds 

      Keogan, Katharine; Daunt, Francis; Wanless, Sarah; Phillips, Richard A.; Walling, Craig A.; Agnew, Philippa; Ainley, David G.; Anker-Nilssen, Tycho; Ballard, Grant; Barrett, Robert T; Barton, Kerry J.; Bech, Claus; Becker, Peter; Berglund, Per-Arvid; Bollache, Loïc; Bond, Alexander L.; Bouwhuis, Sandra; Bradley, Russell W.; Burr, Zofia; Camphuysen, Kees; Catry, Paulo; Chiaradia, Andre; Christensen-Dalsgaard, Signe; Cuthbert, Richard; Dehnhard, Nina; Descamps, Sébastien; Diamond, Tony; Divoky, George; Drummond, Hugh; Dugger, Katie M.; Dunn, Michael J.; Emmerson, Louise; Erikstad, Kjell Einar; Fort, Jérôme; Fraser, William; Genovart, Meritxell; Gilg, Olivier; González-Solís, Jacob; Granadeiro, José Pedro; Grémillet, David; Hansen, Jannik; Hanssen, Sveinn Are; Harris, Mike; Hedd, April; Hinke, Jefferson; Igual, José Manuel; Jahncke, Jaime; Jones, Ian; Kappes, Peter J.; Lang, Johannes; Langset, Magdalene; Lescroël, Amélie; Lorentsen, Svein-Håkon; Lyver, Phil O’B.; Mallory, Mark; Moe, Børge; Montevecchi, William A.; Monticelli, David; Mostello, Carolyn; Newell, Mark; Nicholson, Lisa; Nisbet, Ian; Olsson, Olof; Oro, Daniel; Pattison, Vivian; Poisbleau, Maud; Pyk, Tanya; Quintana, Flavio; Ramos, Jaime A.; Ramos, Raül; Reiertsen, Tone Kirstin; Rodríguez, Cristina; Ryan, Peter; Sanz-Aguilar, Ana; Schmidt, Niels M.; Shannon, Paula; Sittler, Benoit; Southwell, Colin; Surman, Christopher; Svagelj, Walter S.; Trivelpiece, Wayne; Warzybok, Pete; Watanuki, Yutaka; Weimerskirch, Henri; Wilson, Peter R.; Wood, Andrew G.; Philimore, Albert B.; Lewis, Sue (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04-02)
      Reproductive timing in many taxa plays a key role in determining breeding productivity, and is often sensitive to climatic conditions. Current climate change may alter the timing of breeding at different rates across trophic levels, potentially resulting in temporal mismatch between the resource requirements of predators and their prey. This is of particular concern for higher-trophic-level organisms, ...
    • Later at higher latitudes: large-scale variability in seabird breeding timing and synchronicity 

      Burr, Zofia M.; Varpe, Øystein; Anker-Nilssen, Tycho; Erikstad, Kjell E; Descamps, Sébastien; Barrett, Robert T.; Bech, Claus; Christensen-Dalsgaard, Signe; Lorentsen, Svein-Håkon; Moe, Børge; Reiertsen, Tone Kristin; Strøm, Hallvard (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-05-28)
      In seasonal environments, organisms are expected to optimally schedule reproduction within an annual range of environmental conditions. Latitudinal gradients generate a range of seasonality to which we can expect adaptations to have evolved, and can be used to explore drivers of timing strategies across species’ distribution ranges. This study compares the timing of egg hatching in four seabird ...
    • Levedyktighetsanalyser for norske lomvibestander 

      Erikstad, K.E.; Reiertsen, T.K.; Anker-Nilssen, Tycho; Barrett, Robert T.; Lorentsen, Svein-Håkon; Strøm, H.; Systad, G.H. (Research report; Forskningsrapport, 2007-03)
      Hekkebestandene av lomvi (Uria aalge) langs norskekysten har hatt en sterk nedgang i løpet av de siste 45 årene. Den norske fastlandsbestanden utgjør i dag ikke mer enn ca 15 000 par, mens den til sammenligning ble beregnet til 120-160 000 par i begynnelsen av 1960-årene. Den største bestanden i norske områder finnes i dag på Bjørnøya hvor det hekker ca 100 000 par, men også her er bestanden ...
    • Long-term decline in egg size of Atlantic puffins Fratercula arctica is related to changes in forage fish stocks and climate conditions 

      Barrett, Robert T.; Nilsen, Erlend Birkeland; Anker-Nilssen, Tycho (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
      Due to major shifts in the marine ecosystem, many seabirds in the NE Atlantic have experienced short- and long-term breeding failures and population changes. One such seabird is the Atlantic puffin Fratercula arctica, the populations of which have declined in Norway at an annual rate of 2% over a ~30 yr period. Parallel to this decline, we found a significant decline in egg volume at 2 widely ...
    • Modelled drift patterns of fish larvae link coastal morphology to seabird colony distribution 

      Sandvik, Hanno; Barrett, Robert T.; Erikstad, Kjell E; Myksvoll, Mari Skuggedal; Vikebø, Frode Bendiksen; Yoccoz, Nigel Gilles; Anker-Nilssen, Tycho; Lorentsen, Svein-Håkon; Reiertsen, Tone; Skardhamar, Jofrid; Skern-Mauritzen, Mette; Systad, Geir Helge (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-05-13)
      Colonial breeding is an evolutionary puzzle, as the benefits of breeding in high densities are still not fully explained. Although the dynamics of existing colonies are increasingly understood, few studies have addressed the initial formation of colonies, and empirical tests are rare. Using a high-resolution larval drift model, we here document that the distribution of seabird colonies along the ...
    • Prey density in non-breeding areas affects adult survival of black-legged kittiwakes Rissa tridactyla 

      Reiertsen, Tone K.; Erikstad, Kjell E.; Anker-Nilssen, Tycho; Barrett, Robert T.; Boulinier, Thierry; Frederiksen, Morten; González-Solís, Jacob; Grémillet, David; Johns, David; Moe, Børge; Ponchon, Aurore; Skern-Mauritzen, Mette; Sandvik, Hanno; Yoccoz, Nigel Gilles (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-08-27)
      In migratory birds, environmental conditions in both breeding and non-breeding areas may affect adult survival rates and hence be significant drivers of demographic processes. In seabirds, poor knowledge of their true distribution outside the breeding season, however, has severely limited such studies. This study explored how annual adult survival rates of black-legged kittiwakes Rissa tridactyla ...
    • SEAPOP studies in the Barents and Norwegian Seas in 2007 

      Anker-Nilssen, Tycho; Barrett, Robert T.; Bustnes, J.O.; Christensen-Dalsgaard, Signe; Erikstad, K.E.; Fauchald, Per; Lorentsen, Svein-Håkon; Steen, Harald; Strøm, H.; Systad, Geir Helge; Tveraa, Torkild (Research report; Forskningsrapport, 2008-04)
      This is the third annual report of the SEAPOP programme, which was initiated in 2005. In 2007, the work continued at full scale in the Lofoten-Barents Sea area, and similar studies were initiated in the southern part of the Norwegian Sea. The report is divided into three sections. The first is an executive summary, the second presents five selected highlights from the studies in 2007, whereas the ...
    • SEAPOP studies in the Lofoten and Barents Sea area in 2005 

      Anker-Nilssen, Tycho; Barrett, Robert T.; Bustnes, Jan Ove; Erikstad, Kjell E; Fauchald, Per; Lorentsen, Svein Håkon; Steen, Harald; Strøm, Hallvard; Systad, Geir Helge Rødli; Tveraa, Torkild (Research report; Forskningsrapport, 2006)
      This is the first annual report from SEAPOP, a long-term seabird programme aiming to provide and maintain base-line knowledge needed for an improved management of marine areas. For several reasons, the activities in the initial year were restricted to the Lofoten and Barents Sea area, but the programme is designed for implementation on the full national scale within a few years. The report ...
    • SEAPOP studies in the Lofoten and Barents Sea area in 2006 

      Anker-Nilssen, Tycho; Barrett, Robert T.; Bustnes, Jan Ove; Erikstad, Kjell Einar; Fauchald, Per; Lorentsen, Svein-Håkon; Steen, Harald; Strøm, Hallvard; Systad, Geir Helge; Tveraa, T (Research report; Forskningsrapport, 2007-04)
      This is the second annual report of the SEAPOP programme, which was initiated in 2005. In 2006, the programme was extended to the near full scale in the Lofoten-Barents Sea area, but it is aimed for implementation at the national level within few years. The report is divided into three sections. The first is an executive summary, the second presents five selected highlights from the studies in ...
    • SEAPOP. Et nasjonalt sjøfuglprogram for styrket beslutningsstøtte i marine områder 

      Anker-Nilssen, Tycho; Bustnes, J.O.; Erikstad, K.E.; Lorentsen, Svein-Håkon; Tveraa, T.; Strøm, H.; Barrett, Robert T. (Research report; Forskningsrapport, 2005-01)
      SEAPOP (Seabird population management and petroleum operations) er et nasjonalt, kunnskapsoppbyggende program om sjøfugl tilrettelagt for å gi styrket beslutningsstøtte for marine områder. Konseptet ble først utviklet for oljeindustrien i et samarbeid mellom Norsk institutt for naturforskning (NINA) og Den norske stats oljeselskap as (Statoil), men er senere videreutviklet i samarbeid med Norsk ...
    • The status and trends of seabirds breeding in Norway and Svalbard 

      Fauchald, Per; Anker-Nilssen, Tycho; Barrett, Robert T.; Bustnes, Jan Ove; Bårdsen, Bård-Jørgen; Christensen-Dalsgaard, Signe; Descamps, Sebastien; Engen, Sigrid; Erikstad, Kjell E; Hanssen, Sveinn Are; Lorentsen, Svein-Håkon; Moe, Børge; Reiertsen, Tone; Strøm, Hallvard; Systad, Geir Helge (Research report; Forskningsrapport, 2015-03)
      This report presents the updated sizes, trends and spatial distributions of the breeding populations of 17 seabird species breeding in Norway and Svalbard. The analyses are based on available census and monitoring data from SEAPOP; the Norwegian monitoring and mapping program for seabirds. In addition, the report presents results from a species-specific literature review of the most important ...
    • There is more to climate than the North Atlantic Oscillation: a new perspective from climate dynamics to explain the variability in population growth rates of a long-lived seabird 

      Mesquita, Michel d. S.; Erikstad, Kjell E.; Sandvik, Hanno; Reiertsen, Tone; Barrett, Robert T.; Anker-Nilssen, Tycho; Hodges, Kevin I.; Bader, Jürgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-04-29)
      Predicting the impact of global climate change on the biosphere has become one of the most important efforts in ecology. Ecosystems worldwide are changing rapidly as a consequence of global warming, yet our understanding of the consequences of these changes on populations is limited. The North Atlantic Oscillation (NAO) has been used as a proxy for “climate” in several ecological studies, but this ...
    • Unintended consequences: how the recovery of sea eagle Haliaeetus spp. populations in the northern hemisphere is affecting seabirds 

      Hipfner, Mark J.; Blight, Louise K.; Lowe, Roy W.; Wilhelm, Sabina I.; Robertson, Gregory J.; Barrett, Robert T.; Anker-Nilssen, Tycho; Good, Thomas P. (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
      The recovery of sea eagle Haliaeetus spp. populations in the temperate northern hemisphere in the closing decades of the 20th century is one of the great conservation success stories of recent times, but the re-establishment of these apex predators in marine systems has had consequences for seabirds. Sea eagles affect seabirds both directly (by taking adults and offspring and by inducing potentially ...