Sökning: "spawning"
Visar resultat 1 - 5 av 67 avhandlingar innehållade ordet spawning.
1. Growth hormone and somatolactin function during sexual maturation of female Atlantic salmon
Sammanfattning : Background and aims: The growth hormone-insulin-like growth factor I (GH-IGF-I) system is known to act during sexual maturation of female salmonids, but the specific roles are not known. Somatolactin (SL) is a pituitary hormone closely related to GH and is only found in fish. In some species, including salmonids, there are two forms, SLa and SLß. LÄS MER
2. Reproductive pattern and offspring performance in brown trout (Salmo trutta)
Sammanfattning : This thesis deals with how reproductive traits and reproductive behaviour in femalebrown trout (Salmo trutta) are linked to offspring performance.In the small stream Tullviksbäcken, the choice of spawning sites was stronglyinfluenced by short-term fluctuations in stream flow and by substrate quality. LÄS MER
3. Conservation of landlocked Atlantic salmon in a regulated river : Behaviour of migratory spawners and juveniles
Sammanfattning : Hydropower dams represent one of the major threats to river ecosystems today. The dams block migratory routes in many rivers, which is problematic for migratory fish species. Trap-and-transport may be an alternative to fish passage solutions, as a strategy to compensate for lost river connectivity. LÄS MER
4. Spatial Modelling of Coastal Fish – Methods and Applications
Sammanfattning : Environmental factors influence species and habitats on multiple scales creating a mosaic of distribution patterns. Studying factors shaping these patterns are central to our understanding of population dynamics and ultimately ecosystem functioning. LÄS MER
5. The spawning salmon as a resource by recreational use : the case of the wild Baltic salmon and conditions for angling in north Swedish rivers
Sammanfattning : The aim of the thesis is to analyse the preconditions for increasedsalmon angling in the remaining wild salmon rivers in Upper Norrland in northernSweden, as well as to evaluate the present and possible future impacts on the localeconomy. It includes the identification of the internal and external conditions, in what ishere called the Salmon Utilisation Landscape, that influence the present use as well asfuture development of the Baltic salmon as a resource in angling. LÄS MER