• Sjøfugl og marine økosystemer. Status for sjøfugl og sjøfuglenes næringsgrunnlag i Norge og på Svalbard 

      Fauchald, Per; Barrett, Robert T.; Bustnes, Jan Ove; Erikstad, Kjell E; Nøttestad, Leif; Skern-Mauritzen, Mette; Vikebø, Frode Bendiksen (Research report; Forskningsrapport, 2015)
      Denne synteserapporten beskriver hvordan endringene og fluktuasjonene i økosystemene i norske havområder påvirker næringsforholdene for sjøfugl. Disse endringene har konsekvenser for sjøfuglsamfunnene langs kysten, og tilstanden for mange bestander har blitt betegnet som kritisk. Selv om mange bestander går tilbake, er bildet langt fra entydig, og vi finner ingen enkle sammenhenger mellom tilstanden ...
    • 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 ...
    • The stress hormone corticosterone in a marine top predator reflects short-term changes in food availability 

      Barrett, Robert T.; Erikstad, Kjell E.; Sandvik, Hanno; Myksvoll, Mari Skuggedal; Jenni-Eiermann, Susi; Kristensen, Ditte Lyngbo; Moum, Truls; Reiertsen, Tone; Vikebø, Frode Bendiksen (Journal article; Tidsskriftartikkel; Peer reviewed, 2015)
      In many seabird studies, single annual proxies of prey abundance have been used to explain variability in breeding performance, but much more important is probably the timing of prey availability relative to the breeding season when energy demand is at a maximum. Until now, intraseasonal variation in prey availability has been difficult to quantify in seabirds. Using a state-of-the-art ocean ...
    • 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 ...
    • Upwind or downwind: the spring arrival of Arctic Terns Sterna paradisaea at Troms, north Norway 

      Barrett, Robert T. (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-07-13)
      Arctic Terns Sterna paradisaea have a record-long migration between their breeding grounds in the Arctic and wintering areas in the Antarctic. Nevertheless, return dtaes to north Norway were remarkably constant over a 35-y period (1981-2015), arriving in Troms within a 13-d time window in mid to late May. Since 1993, arrival dates have advanced by about four days. No relationships were found between ...
    • Virological and serological surveillance for type A influenza in the black-legged kittiwake (Rissa tridactyla) 

      Tønnessen, Ragnhild; Germundsson, Anna; Jonassen, Christine M.; Haugen, Irene; Berg, Kristin; Barrett, Robert T.; Rimstad, Espen (Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
      The epidemiology of avian influenza viruses (AIVs) in gulls is only partially known. The role of the world's most numerous gull species, the black-legged kittiwake (Rissa tridactyla), as a potential AIV reservoir species has been unclear. The prevalence of AIV and humoral response against AIV were therefore studied in a colony of apparently healthy black-legged kittiwakes breeding in a nesting cliff ...
    • When things go wrong: intra-season dynamics of breeding failure in a seabird 

      Ponchon, Aurore; Grémillet, David J.H.; Christensen-Dalsgaard, Signe; Erikstad, Kjell E; Barrett, Robert T.; Reiertsen, Tone Kristin; McCoy, Karen D.; Tveraa, Torkild; Boulinier, Thierry (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-01-16)
      During breeding, long-lived species face important time and energy constraints that can lead to breeding failure when food becomes scarce. Despite the potential implications of intra-season dynamics in breeding failure for individual behavior, carry-over effects, dispersal decisions and population dynamics, little information is currently available on these dynamics at fine temporal scales. Here, ...