• Centennial relationships between ocean temperature and Atlantic puffin production reveal shifting decennial trends 

      Hansen, Erpur S.; Sandvik, Hanno; Erikstad, Kjell E.; Yoccoz, Nigel; Anker-Nilssen, Tycho; Bader, Jürgen; Descamps, Sebastien; Hodges, Kevin; Mesquita, Michel d. S.; Reiertsen, Tone Kristin; Varpe, Øystein (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-24)
      The current warming of the oceans has been shown to have detrimental effects for a number of species. An understanding of the underlying mechanisms may be hampered by the non-linearity and non-stationarity of the relationships between temperature and demography, and by the insufficient length of available time series. Most demographic time series are too short to study the effects of climate on ...
    • 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 ...
    • Climate-Driven Ichthyoplankton Drift Model Predicts Growth of Top Predator Young 

      Myksvoll, Mari Skuggedal; Erikstad, Kjell E.; Barrett, Robert T.; Sandvik, Hanno; Vikebø, Frode Bendiksen (Journal article; Tidsskriftartikkel; Peer reviewed, 2013-11-12)
      Climate variability influences seabird population dynamics in several ways including access to prey near colonies during the critical chick-rearing period. This study addresses breeding success in a Barents Sea colony of common guillemots Uria aalge where trophic conditions vary according to changes in the northward transport of warm Atlantic Water. A drift model was used to simulate interannual ...
    • Consequences of cross-season demographic correlations for population viability 

      Layton-Matthews, Kate; Reiertsen, Tone Kristin; Erikstad, Kjell E.; Anker-Nilssen, Tycho; Daunt, Francis; Wanless, Sarah; Barrett, Robert; Newell, Mark A; Harris, Mike P. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-12)
      Demographic correlations are pervasive in wildlife populations and can represent important secondary drivers of population growth. Empirical evidence suggests that correlations are in general positive for long-lived species, but little is known about the degree of variation among spatially segregated populations of the same species in relation to environmental conditions. We assessed the relative ...
    • 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, ...
    • Ocean climate and egg investment in the black-legged kittiwake Rissa tridactyla. 

      Barrett, Robert T.; Erikstad, Kjell E.; Reiertsen, Tone (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-09-14)
      Birds allocate substantial resources to their eggs during the laying period, resources also needed for other concurrent costly processes such as mate acquisition, nest building and site defence. Egg and clutch sizes may thus vary in response to food availability prior to egg laying. We investigated the variation in egg and clutch size of black-legged kittiwakes Rissa tridactyla in a North Norwegian ...
    • 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 ...
    • Raising offspring increases ageing: Differences in senescence among three populations of a long-lived seabird, the Atlantic puffin 

      Landsem, Terje Lorentzen; Yoccoz, Nigel Gilles; Layton-Matthews, Kate; Hilde, Christoffer Høyvik; Harris, Michael P; Wanless, Sarah; Daunt, Francis; Reiertsen, Tone Kristin; Erikstad, Kjell E.; Anker-Nilssen, Tycho (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-01-12)
      1. Actuarial senescence, the decline of survival with age, is well documented in the wild. Rates of senescence vary widely between taxa, to some extent also between sexes, with the fastest life histories showing the highest rates of senescence. Few studies have investigated differences in senescence among populations of the same species, although such variation is expected from population-level ...
    • 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 ...
    • Strong migratory connectivity across meta-populations of sympatric North Atlantic seabirds 

      Merkel, Benjamin; Descamps, Sebastien; Yoccoz, Nigel; Grémillet, David; Fauchald, Per; Danielsen, Jóhannis; Daunt, Francis; Erikstad, Kjell E.; Ezhov, Aleksey V.; Harris, Mike P.; Gavrilo, Maria; Lorentsen, Svein-Håkon; Reiertsen, Tone Kristin; Systad, Geir Helge Rødli; Thórarinsson, Thorkell Lindberg; Wanless, Sarah; Strøm, Hallvard (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-04)
      Identifying drivers of population trends in migratory species is difficult, as they can face many stressors while moving through different areas and environments during the annual cycle. To understand the potential of migrants to adjust to perturbations, it is critical to study the connection of different areas used by different populations during the annual cycle (i.e. migratory connectivity). ...
    • 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 ...
    • 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) ...
    • Year-round distribution of Northeast Atlantic seabird populations: applications for population management and marine spatial planning 

      Fauchald, Per; Amélineau, Françoise; Bråthen, Vegard Sandøy; Descamps, Sebastien; Ekker, Morten; Helgason, Halfdan Helgi; Johansen, Malin; Merkel, Benjamin; Moe, Børge; Åström, Jens; Bjørnstad, Oskar; Chastel, Olivier; Christensen-Dalsgaard, Signe; Danielsen, Jóhannis; Daunt, Francis; Dehnhard, Nina; Erikstad, Kjell E.; Ezhov, Alexey; Gavrilo, Maria; Hallgrimsson, Gunnar Thor; Hansen, Erpur Snær; Harris, Mike; Helberg, Morten; Jónsson, Jón Einar; Kolbeinsson, Yann; Krasnov, Yuri V.; Langset, Magdalene; Lorentsen, Svein-Håkon; Lorentzen, Erlend; Newell, Mark; Olsen, Bergur; Reiertsen, Tone Kristin; Systad, Geir Helge Rødli; Thompson, Paul; Thórarinsson, Thorkell Lindberg; Wanless, Sarah; Wojczulanis-Jakubas, Katarzyna; Strøm, Hallvard (Journal article; Tidsskriftartikkel; Peer reviewed, 2021)
      Tracking data of marine predators are increasingly used in marine spatial management. We developed a spatial data set with estimates of the monthly distribution of 6 pelagic seabird species breeding in the Northeast Atlantic. The data set was based on year-round global location sensor (GLS) tracking data of 2356 adult seabirds from 2006−2019 from a network of seabird colonies, data describing the ...