In the present study, using stream-dwelling brown trout (Salmo trutta) as a model species, movement through the summer and autumn in two large Norwegian rivers, River Glomma and River Gudbrandsdalslågen, was observed. In addition fish from each river were sampled for age and growth analysis. The aim of the study was to test for which individual characteristics (sex, body mass, body condition factor, tagging site and cohort) that influenced movement and to test for correlations between growth rates (both immature and mature) and movement (movement during the growth season and spawning migration) on a large spatiotemporal scale. Model selection showed that body condition was negatively related to movement during the growth season and that there was a difference in movement activity between the two rivers. Female body size had a positive effect on the activity level shown for movement during the growth season and spawning period; however no such relationship was found for males. As this relationship has not been shown before in salmonids, the reason for this pattern remains unknown. However, one might speculate that it is related to differences between the two sexes in size-specific energy requirements associated with spawning. Neither movement during the growth season nor spawning migration could be predicted from growth rates experienced as juveniles. This indicates that variation in movement among individuals is not temporally consistent throughout life in brown trout.

Acoustic telemetry was used to study the movements and habitat use of sea trout (Salmo trutta L.) and Arctic char (Salvelinus alpinus (L.)) in Repparfjord in Northern Norway during July until October 2010. In total, 18 trout and 8 char was internally tagged with acoustic depth temperature-tags (ADTT), and 6 trout and 3 char with identification-tags. Detected fish ranged in size with an average (mean±SE) of 27.8±1.6 cm for trout and 29.1±1.8 cm for char. All fish was monitored by 32 stationary hydrophones placed in zones over the fjord system during the whole time period in addition to manual tracking. Concerning temporal aspects results indicated that trout ascend earlier than char, contradicting other findings in areas close to the study area. However, no statistical analysis were carried out due to all fish were captured at sea so no descend time was recorded. Concerning spatial usage data showed results on distance to land and temperature preferences with fish length. However, species had a trend on distance to land and temperature, where char was observed closer to shore and in colder waters. Concerning zone there was a significant difference in spatial habitat usage on interaction between fish length and species as well as on species. There was a trend with a negative relationship on fish length and zone usage for char indicating that smaller fish seek further out in the system in addition to differences between species where trout occupied inner areas and char was detected more often in the outer areas of the system. This is in accordance with earlier studies that states species will exploit different areas of the system. Data collected from the ADTT-tags showed that trout on average preferred slightly warmer (0.7°C warmer) and shallower water (0.59 m. vs. 0.75 m.) than char. However, the only significant here was on temperature with a positive relationship over fish length.

In the last few decades stochastic dynamic modeling (SDM) has been used to explore adaptive state-dependent strategies in a whole host of different theoretical problems in behavioural ecology, with considerable success. It has allowed us to better understand cooperative behaviours such as sentinel behaviour, and it might allow us to more fully understand other cooperative behaviours with alternative dynamics. In a recently developed SDM, anti-predator behaviour was examined and a counter-intuitive prediction has emerged: that mobbing effort should be completely independent of state. In this study we test this interesting prediction, using the cooperatively breeding Apostlebird (Struthidea cinerea) as our study species. From October 15th to November 21st in 2009, 6 groups of varying sizes were put through a set of trials, where we used a rubber snake model to elicit mobbing behaviour in experimental trials. A similarly sized stick was used during control trials, wherein birds tended to forage. Behaviour, placement and vocalisation data on an individual basis were gathered in multiple scan samplings per trial in both kinds of treatment. This highly accurate data was then compared with within-individual differences in body mass (state). Several other variables were also considered: sex, age, breeding status, relatedness and mean body mass. Results show that while foraging behaviour was highly state-dependent during controls, no such effect was found in the mobbing effort of the same individuals during experiments. Mobbing effort also did not vary with any of the mentioned phenotypically fixed variables. Our study therefore offers the first empirical evidence of state-independent mobbing.

Summary1. Migration is present in all animal taxa and is defined as a periodic movement pattern between given ranges. Migratory individuals generally move more directional and with higher speed than stationary individuals during the migration seasons. It is suggested that migratory individuals in these periods encounter more risk factors, and therefore experience a higher mortality.2. I studied the variation in the speed of movement and the number of times migratory and stationary moose were crossing elements associated with mortality risk, i.e. water bodies, roads and railroads, in Central Norway. This was done by examining the movement pattern of 121 GPS-collared moose. I also examined whether realized mortality differed between the two movement strategies. 3. The results only partly supported my hypothesis that migratory moose experience higher costs of movement and are confronted with more risk elements than stationary moose. As predicted, migratory moose moved faster than stationary moose, particularly during the migratory season. However, stationary moose had higher densities of risk elements within their home ranges, and crossed risk elements more frequently than migratory moose. For a given density of risk elements, migratory moose crossed more frequently, supporting the hypothesis that migratory moose are less risk adverse. This pattern was present throughout the year, suggesting that the behavior is not only related to higher movement during the migratory period. 4. I found no effect of movement strategy on the mortality rates, but the sample size was low. However, the trend of realized mortality was opposite of what I expected, with migratory moose having a lower mortality rate than stationary moose.5. My results suggest that migratory moose experience a higher risk of mortality by their movement strategy compared to stationary moose. However, this varies between individuals. By considering individual differences in costs of migration, it is possible to increase our understanding of partial migration. Increased human induced risks such as roads, will most likely increase the number of road crossings. The differences between the two movement strategies in number of crossings will most likely decrease as risk density increase, resulting in a high crossing frequency of risk factors performed by moose.

Summary1. Recruitment failure may represent an important demographic response to changes in the environment or in population size. In this study, I examined whether there was a positive relationship between recruitment rates and ovulation rates in year t-1 in eight Norwegian moose populations. Further, I examined how body condition and climate affected the spatiotemporal variation in recruitment rates and ovulation rates. 2. Both recruitment rates and ovulation rates exhibited spatial and temporal variation. The ovulation and twin ovulation rate in yearlings showed more temporal variation than in prime-aged adults. Furthermore, twinning rates varied more than ovulation and calving rates.3. The number of calves per female recruited to the population was positively related to number of eggs per female the previous year. More calves per female were recorded in years with a high June temperature, smaller snow depths and larger yearling body mass, indicating that more egg cells are realised into a calf in years with good living conditions.,4. Additionally, more calves per female were found in regions with higher number of eggs per female, cool June temperatures and low snow depths. The level of recruitment failure varied among regions, and was highest in Vestfold which is associated with low ovulation rates and body masses. This shows that prenatal or neonatal losses of offspring are likely to be an important demographic response in moose to changes in population size or in the environment.

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An intervention against extreme poverty and hunger was introduced in year 2000, when all members of the United Nations agreed on the Millennium Development Goals (MDG). Today, 1.4 billion people live in poverty and hunger, with poor prospects for increased living standards. Nepal is one of the world’s poorest countries with most of its population living ruraly on low-income agriculture. Due to ongoing climatic changes and financial instability, the international food security is threatened. Inexpensive and low water consuming food production will therefore be an important development for times to come. In line with the MDGs, the NTNU initiated programme Sustainable Poverty Reduction in Nepal (SPRN) have started to utilize Nepal’s rich freshwater resources to develop fish farms in tandem with eco-friendly hydropower projects. The main target is to develop year-round delivery of carp fingerlings in hilly rural areas.Fish are seasonally breeding animals that use environmental signals to coordinate and control their biological rhythms. Photoperiod represents an accurate indicator of time of day and season, and may be translated into a chemical body signal, melatonin, by the pineal gland. Pineal melatonin is released during night and the secretory pattern – which reflects the environmental light/dark cycle – may exhibit one of three known patterns. A daily and annual rhythmic production of melatonin may provide the fish with a physiological capacity to anticipate and prepare for upcoming seasonal changes. Manipulation of the photoperiodic control of pineal melatonin release has been successfully used to initiate biorhythms like spawning in cultured finfish species at mid and high latitudes. The current study was performed to describe the day/night plasma melatonin levels in Common carp (Cyprinus carpio) during November at mid-hills Nepal (28 ºN). It represents the first part of possible development of a maturation control system for low latitude carps. Plasma melatonin levels exhibited a single peak profile during late darkphase and decreased to low daytime levels before the onset of light. When subjected to an extended night period, carp plasma melatonin rhythm appeared to repeat this profile from natural photoperiod, which may indicate a circadian clock system at work. Blood plasma cortisol levels were elevated during these experiments but are not expected to have stimulated the melatonin release. These results demonstrate a possible complex melatonin control system of type B in the Common carp kept at low latitude (Nepal).

Dagens problem med lakselus på atlantisk laks (Salmo salar) er betydelig, og bakgrunn for store økonomiske tap. Fiskeridirektoratet anslår at 80 % av tap i matproduksjon av atlantisk laks er forårsaket av lakselus. Nasjonalpolitiske bestemmelser tydeliggjør satsningen på bekjempelse av lakselus i Norge. Biologisk avlusning med bruk av leppefisk er i sterk fokus for flere aktører i laskeoppdrettsnæringen, og det er et stort behov for økologisk og biologisk kunnskap om leppefisk. Leppefiskfamilien (Labridae) er svært artsrik med mer enn 500 arter globalt, hvor få naturlige leppefiskarter er å finne i Norge. Tre av dem har vist sin nytteverdi som lusepisere. Bergnebb (Ctenolabrus rupestris) er en av disse, og har størst forekomst langs norskekysten. Tilgang på leppefisk for bruk i lakseoppdrett er i dag basert på villfangst og biltransport. Sykdom og dødelighet er imidlertid et stort problem relatert til de påvirkninger som fisken blir utsatt for ved disse prosessene. Metabolisme og stressrespons hos bergnebb er tema for denne oppgaven, hvor det nærmere undersøkes betydningen av Aqui-S sedasjon for bergnebb i simulert transport. En næringsrettet tilnærming med spesielt fokus på transport av leppefisk er bakgrunn for målinger i småskala oppsett som tillater fri bevegelse hos bergnebb under forsøk.Oksygenforbruk hos villfanget bergnebb viste stor spredning for individer i forhold til vekt og temperaturendring. Vinterakklimert fisk viste samlet redusert oksygenforbruk sammenlignet med sommerakklimerte. Stress ved plasma kortisol viste uendrede verdier for 10- og 30 minutter post lufteksponering som kontrollverdier og indikerer ukjente stresseffektorer for bergnebb i fangenskap. Stressrespons antydes redusert ved Aqui-S sedasjon ved 2,5-7,5 ppm, og gir ingen endring i løpet av 20 min. for oksygenforbruk ved introduksjon.

In the sensory systems of insects, the primary olfactory centre in the antennal lobe has been one of the major areas of interest for the last two decades. Considerable progress has been made in understanding this earlier part of the olfactory network, whereas very little is known about the odour processing of the higher order centres within the protocerebrum. In this study, the olfactory system of the moth Heliothis virescens was employed as a model. Intracellular recordings and stainings of neurons in the higher order olfactory centre in the lateral protocerebrum (LP) were performed during stimulation with identified primary plant odorants and multicomponent blends. Neurons were visualized by scanning with confocal laser microscope and 3-dimensional reconstructions. In order to morphologically identify and characterize neurons in the LP, recontructed neurons were registered into a standard brain atlas that has been developed for this species. Two different analyses were performed on the obtained physiology. First, a cluster analysis revealed clear divitions with respect to different neurons interspike interval (ISI) distributions, thus indicating groups of neurons with different functional properties within the higher order olfactory network. Secondly, a novel method in which to quantify complex temporal response patterns was introduced. A t-test used to compare the quantified reponses to single odorants versus blends showed that the majority of neurons ( ~70%) in the LP responded stronger to multicomponent blends. This indicated a predominant synergistic interaction of plant odours in the higher order olfactory centre of H. virescens.

γ-aminobutyric acid (GABA) is the main inhibitory neurotransmitter in all known nervous systems, and it is widely distributed in the olfactory circuit as well as other parts of the invertebrate brain. In order to further understand the GABAergic olfactory circuitry, the distribution of GABA in the brain of a nuctoid moth, Heliothis virescens, was investigated. Immunohistochemical experiments with an antibody against GABA were performed in order to visualize GABAergic structures and neurons. The stainings revealed strong immunoreactivity in the antennal lobes, the lateral protocerebrum, and the mushroom bodies, all of which are areas involved in olfactory information processing. The dense immunostaining in the lateral protocerebrum included a brightly immunoreactive cell cluster linked to processes innervating the mushroom bodies; this likely corresponds to the protocerebral calycal tract described in other species. Of the main antenno-protocerebral tracts, fibers in the medio-lateral showed strong immunoreactivity. However, double labeling of two intracellularly pre-stained projection neurons passing in this tract showed that not all fibers therein are GABAergic. Looking at the projection pattern of these neurons, it seems likely that they belong to a different morphological class of projection neurons than the GABAergic ones.Some methodologically important issues were also discovered in the study, the most significant being that the identity of not only the primary but also of the secondary antibody is of great importance to the quality of the results.