Browsing Department of Biological Sciences by Title

Now showing items 1210-1229 of 2225

    • 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 ...

    • Large mesopelagic fishes biomass and trophic efficiency in the open ocean 

      Irigoien, Xabier; Klevjer, Thor A.; Røstad, Anders; Martinez, U.; Boyra, G.; Acuna, J. L.; Bode, A.; Echevarria, F.; Gonzalez-Gordillo, J. I.; Hernández-León, Santiago; Augsti, S.; Aksnes, Dag Lorents; Duarte, C. M.; Kaartvedt, Stein (Peer reviewed; Journal article, 2014-02-07)
      With a current estimate of ~1,000 million tons, mesopelagic fishes likely dominate the world total fishes biomass. However, recent acoustic observations show that mesopelagic fishes biomass could be significantly larger ...

    • Last Glacial Maximum environmental conditions at Andøya, northern Norway; evidence for a northern ice-edge ecological “hotspot” 

      Alsos, Inger Greve; Sjøgren, Per Johan E; Brown, Antony; Gielly, Ludovic; Merkel, Marie Føreid; Paus, Aage; Lammers, Youri; Edwards, Mary E.; Alm, Torbjørn; Leng, Melanie; Goslar, Tomasz; Langdon, Cathrine; Bakke, Jostein; Van Der Bilt, Willem (Journal article; Peer reviewed, 2020)
      Andøya on the NW coast of Norway is a key site for understanding the Last Glacial Maximum (LGM) in northern Europe. Controversy has arisen concerning the local conditions, especially about the timing and extent of local ...

    • Last-century vegetational changes in northern Europe. Characterisation, causes, and consequences 

      Kapfer, Jutta (Doctoral thesis, 2011-11-04)
      In the face of recent changes in environmental conditions and climate, longterm studies provide important insights into patterns and processes of vegetational change. In northern Europe, however, long-term studies are rare ...

    • Late Quaternary chironomid community structure shaped by rate and magnitude of climate change 

      Mayfield, Roseanna J.; Langdon, Peter G.; Doncaster, C. Patrick; Dearing, John A.; Wang, Rong; Velle, Gaute; Davies, Kimberley L.; Brooks, Stephen J. (Journal article; Peer reviewed, 2021)
      Much is known about how climate change impacts ecosystem richness and turnover, but we have less understanding of its influence on ecosystem structures. Here, we use ecological metrics (beta diversity, compositional disorder ...

    • Latitudinal differences in early growth of largehead hairtail (Trichiurus japonicus) in relation to environmental variables 

      Sun, Peng; Chen, Qi; Fu, Caihong; Xu, Yi; Sun, Runlong; Li, Jianchao; Yu, Haiqing; Zhang, Chi; Liu, Yang; Ye, Zhenjiang; Tian, Yongjun; Heino, Mikko Petteri (Journal article; Peer reviewed, 2020)
      Largehead hairtail (Trichiurus japonicus) in the China Seas shows an increasing catch trend, despite continued overexploitation, which could be attributed to improved recruitment as a result of strengthened early growth. ...

    • Learning through practice in biology education 

      Hole, Torstein Nielsen (Doctoral thesis, 2019-04-25)
      Work continues to be an important educational measure in higher education. It has received increasing focus both among policymakers, educators, and in educational science research as a valuable addition to campus-based, ...

    • Lemon sole Microstomus kitt in the northern North Sea: a multidisciplinary approach to the early life-history dynamics 

      Geffen, Audrey J.; Albretsen, Jon; Huwer, Bastian; Nash, Richard David Marriott (Journal article; Peer reviewed, 2021)
      Lemon sole Microstomus kitt is a commercially valuable flatfish species that occurs in shelf waters around the northeast Atlantic. Only the most basic life-history information is available for the North Sea. Spawning is ...

    • Length Related Diurnal Vertical Migration of Cod (Gadus morhua L.), Haddock (Melanogrammus aeglefinus L.) and Redfish (Sebastes spp.) in the Barents Sea 

      Einarsson, Haraldur Arnar (Master thesis, 2001)
      Vertical fish migrations can increase variability in bottom survey data, especially if unknown diurnal length-frequency distribution is different between layers. Surveys, using echo sounder technique to estimate demersal ...

    • Leptin receptor-deficient (knockout) zebrafish: Effects on nutrient acquisition 

      Del Vecchio, Gianmarco; Murashita, Koji; Verri, Tiziano; Gomes, Ana Cristina Da Silva; Rønnestad, Ivar (Journal article; Peer reviewed, 2021)
      In mammals, knockout of LEPR results in a hyperphagic, morbid obese, and diabetic phenotype, which supports that leptin plays an important role in the control of appetite and energy metabolism, and that its receptor, LEPR, ...

    • Leucine did not stimulate growth and accretion in either stressed or unstressed Atlantic salmon 

      Espe, Marit; Lai, Floriana; Gomes, Ana S.; De Santis, Christian; Hartviksen, Mali B.; Holen, Elisabeth; Rønnestad, Ivar (Journal article; Peer reviewed, 2021)
      The aim of the current trial was to test whether leucine affected growth and accretion including test any effects on leucine upon stress. Quadruplicate tanks each containing 50 Atlantic salmon (Salmo salar) (mean start ...

    • Life after fire: smoke and ash as germination cues in ericads, herbs and graminoids of northern heathlands 

      Bargmann, Tessa; Måren, Inger Elisabeth; Vandvik, Vigdis (Peer reviewed; Journal article, 2014-05-02)
      Question: What is the impact of the fire cues smoke and ash on seed germination of important functional groups in the heathland system, namely ericads, herbs and graminoids? We predict that if germination from heathland ...

    • Life after fire: the impact of fire on species composition and diversity in coastal heathlands 

      Bargmann, Tessa (Doctoral thesis, 2015-09-11)
      Fire prone coastal heathlands are widespread, and range from naturally fire prone Mediterranean-type heathlands, to the anthropogenic heathlands of north-west Europe. Regardless of its source, fire is an important disturbance ...

    • Life histories determine divergent population trends for fishes under climate warming 

      Wang, Hui-Yu; Shen, Sheng-Feng; Chen, Ying-Shiuan; Kiang, Yun-Kae; Heino, Mikko Petteri (Journal article; Peer reviewed, 2020-08-14)
      Most marine fish species express life-history changes across temperature gradients, such as faster growth, earlier maturation, and higher mortality at higher temperature. However, such climate-driven effects on life histories ...

    • Life histories of Antarctic incirrate octopods (Cephalopoda: Octopoda) 

      Schwarz, Richard; Hoving, Henk-Jan; Noever, Christoph; Piatkowski, Uwe (Journal article; Peer reviewed, 2019-07-11)
      As a general trend in the life history of marine organisms, species inhabiting cold waters have reduced growth rates and increased lifespans. Studies based on egg sizes and brooding times of deep-sea and polar octopods ...

    • Life history adaptations to seasonality 

      Varpe, Øystein Heggernes (Doctoral thesis, 2007-02-16)
      The thesis contains studies of animal life histories at high latitudes. Several topics are covered; from ecosystem consequences of life histories to tests of specific behavioural predictions put forward based on life history ...

    • Life history traits for Ophryotrocha craigsmithi (Wiklund, Glover & Dahlgren, 2009), a candidate species in integrated multitrophic aquaculture 

      Svensson, Signe Gunborg Bentzröd; Strohmeier, Tore; Rastrick, Helen; Aguera, Antonio; Lock, Erik Jan Robert; Sveier, Harald; Jansen, Henrice M (Journal article; Peer reviewed, 2023-02-07)
      Ophryotrocha craigsmithi (Wiklund, Glover & Dahlgren, 2009) has repeatedly been observed in high densities at salmonid fish farms in Norway and has been shown to feed on the organic waste released during fish production. ...

    • Life in the fast lane: Revisiting the fast growth—High survival paradigm during the early life stages of fishes 

      Robert, Dominique; Shoji, Jun; Sirois, Pascal; Takasuka, Akinori; Catalán, Ignacio A.; Folkvord, Arild; Ludsin, Stuart A.; Peck, Myron A.; Sponaugle, Su; Ayón, Patricia M.; Brodeur, Richard D.; Campbell, Emily Y.; D'Alessandro, Evan K.; Dower, John F.; Fortier, Louis; García, Alberto G.; Huebert, Klaus B.; Hufnagl, Marc; Ito, Shin-ichi; Joh, Mikimasa; Juanes, Francis; Nyuji, Mitsuo; Oozeki, Yoshioki; Plaza, Guido; Takahashi, Motomitsu; Tanaka, Yosuke; Tojo, Naoki; Watari, Shingo; Yasue, Naotaka; Pepin, Pierre (Journal article; Peer reviewed, 2023)
      Early life survival is critical to successful replenishment of fish populations, and hypotheses developed under the Growth-Survival Paradigm (GSP) have guided investigations of controlling processes. The GSP postulates ...

    • Life-history evolution in response to foraging risk, modelled for Northeast Arctic cod (Gadus morhua) 

      Jessen, Henrik Høiberg; Opdal, Anders Martin Frugård; Enberg, Katja Susanna (Journal article; Peer reviewed, 2023)
      Foraging behaviour is known to be a key element in ecology and evolution. Increased foraging intensity increases energy intake, which is useful for growth and reproduction but comes at the cost of higher mortality risk due ...

    • 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, ...