• Climate fluctuations and differential survival of bridled and non-bridled Common Guillemots Uria aalge 

      Reiertsen, Tone Kristin; Erikstad, Kjell E; Barrett, Robert T; Sandvik, Hanno; Yoccoz, Nigel (Journal article; Tidsskriftartikkel; Peer reviewed, 2012-06-22)
      Climate fluctuations and its effects on ecological processes are evident in most areas worldwide but whether such climatic effects are induced phenotypic plasticity or whether animals adapt to the new environment through micro‐evolutionary processes is poorly known. In this study we have analyzed long‐term data (22 years) on the relationship between climatic fluctuations and the adult survival of ...
    • Effekter av forurensning på bestandsutviklingen til måser 

      Reiertsen, Tone Kristin; Erikstad, Kjell Einar (Research report; Forskningsrapport, 2007-06)
      Måser er toppredatorer i det marine miljø, og er svært utsatt for miljøgifter. Hos arter som sildemåse (Larus fuscus), svartbak (Larus marinus) og polarmåse (Larus hyperboreus) er det dokumentert høye nivåer av organokloriner (OC), som nedsetter immunforsvaret og gir økt forekomst av sykdom, noe som medfører både redusert hekkesuksess og overlevelse av voksne. Selv om det er dokumentert en rekke ...
    • Hemispheric asymmetry in ocean change and the productivity of ecosystem sentinels 

      Sydeman, William J.; Schoeman, David S.; Thompson, Sarah Ann; Hoover, Brian A.; García-Reyes, Marisol; Daunt, Francis; Agnew, Philippa; Anker-Nilssen, Tycho; Barbraud, Christophe; Barrett, Robert; Becker, Peter H.; Bell, Elisabeth; Boersma, P. Dee; Bouwhuis, Sandra; Cannell, Belinda; Crawford, Robert J. M.; Dann, Peter; Delord, Karine; Elliot, Graeme; Erikstad, Kjell E.; Flint, Elizabeth; Furness, Robert W.; Harris, Michael P.; Hatch, Scott; Hilwig, Kara; Hinke, Jefferson T.; Jahncke, Jaime; Mills, James A.; Reiertsen, Tone Kristin; Renner, Heather; Sherley, Richard B.; Surman, Christopher; Taylor, Graeme; Thayer, Julie A.; Trathan, Phil N.; Velarde, Enriqueta; Walker, Kath; Wanless, Sarah; Warzybok, Pete; Watanuki, Yutaka (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-28)
      Climate change and other human activities are causing profound effects on marine ecosystem productivity. We show that the breeding success of seabirds is tracking hemispheric differences in ocean warming and human impacts, with the strongest effects on fish-eating, surface-foraging species in the north. Hemispheric asymmetry suggests the need for ocean management at hemispheric scales. For the north, ...
    • 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 ...
    • Twilight foraging enables European shags to survive the winter across their latitudinal range 

      Moe, Børge; Daunt, Francis; Bråthen, Vegard Sandøy; Barrett, Robert; Ballesteros, Manuel; Bjørnstad, Oskar; Bogdanova, Maria I.; Dehnhard, Nina; Erikstad, Kjell E.; Follestad, Arne; Gíslason, Sindri; Hallgrimsson, Gunnar Thor; Lorentsen, Svein-Håkon; Newell, Mark; Petersen, Aevar; Phillips, Richard A.; Ragnarsdóttir, Sunna Björk; Reiertsen, Tone Kristin; Åström, Jens; Wanless, Sarah; Anker-Nilssen, Tycho (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-14)
      Species breeding at high latitudes face a significant challenge of surviving the winter. Such conditions are particularly severe for diurnal marine endotherms such as seabirds. A critical question is therefore what behavioural strategies such species adopt to maximise survival probability. We tested 3 hypotheses: (1) they migrate to lower latitudes to exploit longer day length (‘sun-chasing’), (2) ...
    • 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, ...