Abnormal Migratory Behaviour in Swedish Reindeer

Attributes the failure of reindeer to return to summer ranges, after being trucked there 150-300 km from winter ranges, to destruction of the herds' social organization, the importance of uninterrupted learning of the migratory route, disorientation caused by unfamiliar winter areas, and a large proportion of inexperienced animals in the herds

Behavioural effects on environmental pollution in threespine stickleback Gasterosteus aculeatus L

The aims of this study were to investigate the effects of known environmental contaminants on defined behavioural variables in fish, and to discuss properties of these behavioural traits that make them useful as potential indicators of pollution. In studying the effects of pollution, the resulting biochemical and physiological alterations are more commonly measured. However, effects of pollution can manifest itself at all levels of biological organisation, including behaviour. In this respect, behaviour can be considered a valid biomarker of pollution in that it is expected to be both susceptible to pollution and of high ecological significance, as it influences the fitness of the affected individuals. This thesis is based on four individual studies, in which the threespine stickleback Gasterosteus aculeatus was used as a model species. Results from these studies show that antipredator behaviour, feeding behaviour, shoaling behaviour, bottom-dwelling behaviour and reproductive behaviour are all sensitive to exposure to sublethal concentrations of defined environmentally relevant chemicals. The results showed that antipredator behaviour and fright response in threespine stickleback were impaired following exposure to sublethal concentrations of bis(tributyltin)oxide (TBTO). However, for some of the tested antipredator variables the effects were reversed after the ending of exposure. Further, it was shown that feeding motivation in fish exposed to butyl benzyl phthalate (BBP) and/or 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE) was increased in that exposed fish initiated feeding more often than the controls. Exposure to BBP also caused sticklebacks to aggregate into tight shoals and to spend more time at the bottom of the aquarium compared to the control fish. The reported significant differences between the controls and BBPexposed fish with respect to feeding and shoaling behaviour were shown even though the levels of BBP were below the analytical detection limit. Different suggested explanations, for example, too high detection limit, or degradation to its BBP metabolites are given to this result. 17β-Oestradiol (E2) exposed male sticklebacks started nest building later than non-exposed males, but there were no differences between exposed and control males with respect to the number of males that built nests. Further, the exposed males spent less time displaying paternal care compared to the control males, although there were no differences between the two groups in the number of performed courtship displays. Because of the significant effect upon some but not all reproductive behavioural traits, it was suggested that the different variables might vary in sensitivity, implying that a variety of variables should be studied in order to obtain a more reliable evaluation of the effects of pollution. Chemicals can cause deleterious effects at one or more levels of biological organisation, from biochemical, physiological, individual, population and through to the ecosystem levels. In contrast to the established hypothesis that a pollutant affects the different biological levels in an escalating timedependent pattern, starting at the biochemical level, it is here suggested that biomarkers at the biochemical, physiological and behavioural levels often will respond early and simultaneously in the same individual. Whereas some biochemical responses are specifically related to one class of exposure agents and thus may act as specific indicators of pollution, most behavioural traits may be altered in response to a variety of chemicals. One exception may be alterations in reproductive behaviour caused by endocrine disrupting chemicals, due to effects of the chemicals on hormones that result in immediate reproductive behavioural effects. In spite of the specific action of some biochemical biomarkers, they are often considered to be of little ecological relevance since many of them are not related to individual fitness. In this thesis, it is argued that behavioural variables can be employed as useful and reliable biomarkers of environmental contamination. It is also important to focus on behaviour to map and quantify the resposes. However, to reliably evaluate the effects of pollution, behavioural variables should be used in association with biochemical and physiological traits. Moreover, optimal combination of results from laboratory and field experiments would enhance the ecological relevance of the study.dr.scient.dr.scient

Power Flow Tracing for Norwegian Offshore Electrification

Det er generelt kjent at elektrisk kraft ikke kan spores fysisk i kraftsystemer med mer enn én leverandør og én forbruker. Janusz Bialek forklarte dette med å si at det er "umulig å ’fargelegge’ innkommende strømmer (til en node) og sjekke fargen på utstrømningene". Med Power Flow Tracing (PFT, kraftflyt-sporing på norsk) er det mulig å teoretisk spore den elektriske kraften, og med det gi estimater av hvordan energi strømmer fra spesifikke generatorer til spesifikke laster. Før gjennomføring av PFT på et kraftsystem er det behov for en kraftflytanalyse eller historiske måleverdier. PFT kan brukes til f.eks. prissetting av overføringstjenester, effektiv bruk av lastreduksjon og fordeling av CO2-utslipp. Sistnevnte blir veldig relevant på grunn av klimaendringene og global oppvarming, det kan forbedre kunnskapen om hvordan strømforbruk påvirker utslipp av klimagasser. I denne masteroppgaven har det blitt utviklet en modell basert på PFT i programmeringsspråket Python. Modellen, som er konfidensiell og ment for intern bruk på NTNU, ble kalt PFT-modellen. Den beregner både generatorer og laster sine bidrag til kraftsystemet, og visualiserer resultatene på et kart av Europa. Den ble demonstrert på scenarier med offshore elektrifisering i Norge. Kraftflytanalysen av disse scenariene, som ga inngangsdata til PFT-modellen, ble gjort i EMPS i spesialiseringsprosjektet. Scenariene inkluderte to grader av elektrifisering av offshoreplattformer: hel og delvis, og de ble satt til år 2025. Resultatene fra simuleringer med PFT-modellen avslørte hvordan energi ville strømme til og fra installasjoner på den norske kontinentalsokkelen, hvis de skulle blitt elektrifisert. Selv om det ble funnet at noe av den importerte kraften ble produsert med CO2-intens kull, ville det totale utslippet knyttet til plattformene blitt redusert med elektrifisering. Sesongbaserte og daglige variasjoner som påvirker kraftsystemet, f.eks. mest vind om vinteren og mest kraftbehov om dagen, ble også oppdaget og forklart. Med disse fornuftige resultatene, og en vurdering av begrensninger, ble det konkludert med at PFT-modellen var vellykket.It is generally known that in power systems with more than one supplier and one consumer, electric power cannot be physically traced. Janusz Bialek explained this by saying that it is "impossible to ’dye’ the incoming flows (to a node) and check the colour of the outflows". With Power Flow Tracing (PFT) it is possible to theoretically trace the electric power, and by that give estimations of how energy flows from specific generators to specific loads. Before performing PFT on a power system there is need for a power flow analysis or historical measured values. PFT can be used for e.g. transmission service pricing, efficient use of load shedding and CO2-emission apportioning. The latter is becoming very relevant due to the climate changes and global warming, it could improve knowledge about how power consumption affect the emission of greenhouse gases. In this Master’s thesis a model based on PFT has been developed in the programming language Python. The model, which is confidential and meant for in-house use at NTNU, is called the PFT Model. It both calculates generators and loads contribution to the power system, and visualises the results in a map of Europe. It was demonstrated on scenarios with offshore electrification in Norway. The power flow analysis of these scenarios, which provided the input data to the PFT Model, was done in EMPS in the specialisation project. The scenarios included two degrees of electrification of offshore platforms: full and partial, and they were set to year 2025. The results from simulations with the PFT Model revealed how energy would flow to and from installations on the Norwegian continental shelf, if they were to be electrified. Even though some of the imported power was found to be produced with CO2-dense coal, the total emission associated with the platforms would be reduced with electrification. Seasonal and daily variations that impact the power system, e.g. most wind in the winter and most power demand during the day, were discovered and explained as well. With these sensible results, and an assessment of limitations, it was concluded that the PFT Model was successful

Behavioural lateralisation in reindeer

Reindeer (Rangifer tarandus) kept in corrals or otherwise forced to clump typically start milling in response to stressing events. This behaviour is generally considered to have an antipredator effect. An inquiry on herd behaviour, to which 35 Norwegian reindeer husbandry districts responded, showed that 32 experienced that corralled rein¬deer consistently circled leftwards, whereas the remaining three reported consistently rightward circling. Regular monitoring of a reindeer herd in central Norway over a two-year period (1993-94), and experimental studies on a fraction of the same herd, revealed the following traits. Free-ranging reindeer showed no right- or left-turning preference during grazing or browsing, but when the reindeer were driven into corrals or forced to clump in the open they invariably rotated leftwards. The circling of corralled reindeer was triggered at an average group size of 20 to 25 animals, apparently independently of the age and sex of the animals. When they dug craters in the snow to reach food, the reindeer used their left foreleg significantly more often than their right. In 23 out of 35 reindeer, the right hemisphere of the brain was heavier than the left. However, in the sample as a whole, the weights of the left and right hemispheres did not differ significantly. Lateralised behaviour in reindeer is thought to be determined by natural and stress induced asymmetries in brain structure and hormonal activity. In addition, learning is probably important for passing on the behaviour between herd members and generations. Differences in lateralised behaviour between nearby herds are thought to be related primarily to different exposure to stress and learning, whereas genetical and environmental fac¬tors (e.g. diet), age structure and sex ratio are probably more important for explaining differences between distant pop¬ulations

CtrlAQUA - Annual Report 2022 - Centre for Closed-Containment Aquaculture

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FutureEUAqua – future growth in sustainable, resilient and climate friendly organic and conventional European aquaculture

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Editorial: Biology Meets Technology: Aquatic Animals in Novel and New Aquaculture Production Systems

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Interpopulational and seasonal variation in the chemical signals of the lizard Gallotia galloti

Communicative traits are strikingly diverse and may vary among populations of the same species. Within a population, these traits may also display seasonal variation. Chemical signals play a key role in the communication of many taxa. However, we still know far too little about chemical communication in some vertebrate groups. In lizards, only a few studies have examined interpopulational variation in the composition of chemical cues and signals and only one study has explored the seasonal effects. Here we sampled three subspecies of the Tenerife lizards (Gallotia galloti) and analyze the lipophilic fraction of their femoral gland secretions to characterize the potential interpopulational variation in the chemical signals. In addition, we assessed whether composition of these secretions differed between the reproductive and the non-reproductive season. We analyzed variations in both the overall chemical profile and the abundance of the two main compounds (cholesterol and vitamin E). Our results show interpopulational and seasonal differences in G. gallotia chemical profiles. These findings are in accordance with the high interpopulational variability of compounds observed in lizard chemical signals and show that their composition is not only shaped by selective factors linked to reproductive season

Atlantic Salmon (Salmo salar) Performance Fed Low Trophic Ingredients in a Fish Meal and Fish Oil Free Diet

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