Blar i Bergen Open Research Archive på forfatter "Jørgensen, Christian"
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Large annual variation in the amount of skipped spawning for female Northeast Arctic haddock Melanogrammus aeglefinus
Skjæraasen, Jon Egil; Korsbrekke, Knut; Dingsør, Gjert Endre; Langangen, Øystein; Opdal, Anders Frugård; Jørgensen, Christian (Journal article; Peer reviewed, 2020-10)Although the phenomenon of skipped spawning has been described in numerous fishes, time-series are scarce. We used the presence of post-ovulatory follicles in histological gonad slides from females not developing oocytes ... -
Life-history implications of the allometric scaling of growth
Boukal, David S.; Dieckmann, Ulf; Enberg, Katja; Heino, Mikko Petteri; Jørgensen, Christian (Peer reviewed; Journal article, 2014-10-21)Several phenomenological descriptions, such as the von Bertalanffy growth model, have been widely used to describe size-at-age and individual growth across a diverse range of organisms. However, for modelling life histories, ... -
Light comfort zone in a mesopelagic fish emerges from adaptive behaviour along a latitudinal gradient
Langbehn, Tom; Aksnes, Dag Lorents; Kaartvedt, Stein; Fiksen, Øyvind; Jørgensen, Christian (Peer reviewed; Journal article, 2019)Throughout the oceans, small fish and other micronekton migrate between daytime depths of several hundred meters and near-surface waters at night. These diel vertical migrations of mesopelagic organisms structure pelagic ... -
Long-term change in a behavioural trait: truncated spawning distribution and demography in Northeast Arctic cod
Opdal, Anders Frugård; Jørgensen, Christian (Peer reviewed; Journal article, 2015-04)Harvesting may be a potent driver of demographic change and contemporary evolution, which both may have great impacts on animal populations. Research has focused on changes in phenotypic traits that are easily quantifiable ... -
Maintaining quality assessment practices in Norwegian higher education after the two-evaluator law
Harlap, Yael; Jørgensen, Christian; Cotner, Sehoya Harris (Journal article; Peer reviewed, 2022)In May 2021, the Norwegian parliament voted unanimously to again require the use of two evaluators to assess all student work given a grade on the A-F scale in higher education. This revision of the law regulating higher ... -
Modelling and interpreting fish bioenergetics: a role for behaviour, life-history traits and survival trade-offs
Jørgensen, Christian; Enberg, Katja; Mangel, Marc (Peer reviewed; Journal article, 2016-01)Bioenergetics is used as the mechanistic foundation of many models of fishes. As the context of a model gradually extends beyond pure bioenergetics to include behaviour, life-history traits and function and performance of ... -
Natural mortality: Its ecology, how it shapes fish life histories, and why it may be increased by fishing
Jørgensen, Christian; Holt, Rebecca (Peer reviewed; Journal article, 2013-01)A stronger focus on natural mortality may be required to better understand contemporary changes in fish life histories and behaviour and their responses to anthropogenic drivers. Firstly, natural mortality is the selection ... -
Nesting synchrony and clutch size in migratory birds: Capital versus income breeding determines responses to variable spring onset
Ejsmond, Anna; Forchhammer, Mads; Varpe, Øystein; Jónsson, Jón Einar; Jørgensen, Christian (Journal article; Peer reviewed, 2021)Synchronous reproduction of birds has often been explained by benefits from nesting together, but this concept fails to explain observed intraspecific variation and climate-mediated changes of breeding synchrony. Here, we ... -
Parent-offspring conflict over reproductive timing: ecological dynamics far away and at other times may explain spawning variability in Pacific herring
Ljungström, Anna Jeja Gabriella; Francis, Tessa; Mangel, Marc; Jørgensen, Christian (Peer reviewed; Journal article, 2019)Timing of reproduction may be of crucial importance for fitness, particularly in environments that vary seasonally in food availability or predation risk. However, for animals with spatially separated feeding and breeding ... -
Poleward distribution of mesopelagic fishes is constrained by seasonality in light
Langbehn, Tom; Aksnes, Dag Lorents; Kaartvedt, Stein; Fiksen, Øyvind; Ljungström, Anna Jeja Gabriella; Jørgensen, Christian (Journal article; Peer reviewed, 2022)Aim: Mesopelagic fishes have a near-global distribution in the upper 1,000 m from tropical to sub-Arctic oceans across temperature regimes. Yet, their abundance decreases poleward and viable populations seem excluded from ... -
The proximate architecture for decision-making in fish
Andersen, Bjørn Snorre; Jørgensen, Christian; Eliassen, Sigrunn; Giske, Jarl (Peer reviewed; Journal article, 2016-09)Evolution has since the very beginning resulted in organisms which can sort fitness-related information from noise, evaluate it and respond to it. In animals, the architecture for proximate control of behaviour and physiology ... -
Response: Demography affects spawning location in Northeast Arctic cod, but what affects demography?
Opdal, Anders Frugård; Jørgensen, Christian (Journal article, 2015-06-19) -
Smaller classes promote equitable student participation in STEM
Ballen, Cissy J.; Aguillon, Stepfanie M.; Awwad, Azza; Bjune, Anne Elisabeth; Challou, Daniel; Drake, Abby Grace; Driessen, Michelle; Ellozy, Aziza; Ferry, Vivian E.; Goldberg, Emma E.; Harcombe, William; Jensen, Steve; Jørgensen, Christian; Koth, Zoe; McGaugh, Suzanne; Mitry, Caroline; Mosher, Bryan; Mostafa, Hoda; Petipas, Renee H.; Soneral, Paula A.G.; Watters, Shana; Wassenberg, Deena; Weiss, Stacey L.; Yonas, Azariah; Zamudio, Kelly R.; Cotner, Sehoya Harris (Peer reviewed; Journal article, 2019)As science, technology, engineering, and mathematics (STEM) classrooms in higher education transition from lecturing to active learning, the frequency of student interactions in class increases. Previous research documents ... -
Trade-offs between growth and reproduction in wild Atlantic cod
Folkvord, Arild; Jørgensen, Christian; Korsbrekke, Knut; Nash, Richard David Marriott; Nilsen, Trygve; Skjæraasen, Jon Egil (Peer reviewed; Journal article, 2014-04-08)Animals partition and trade off their resources between competing needs such as growth, maintenance, and reproduction. Over a lifetime, allocation strategies should result in distinct trajectories for growth, survival, and ...