Sten Ivar Siikavuopio

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We compared the gonad-enhancing effects of two diets (NIWA and NIFA diets) in two size classes of sea urchins (Evechinus chloroticus): small and large urchins with a test diameter of 75.6 ± 1.2 mm and 93.8 ± 0.5 mm, weighing 174.8 ± 7.9 g and 315 ± 5.6 g, respectively. After eight weeks being fed prepared diets, urchin gonad index (GI) had significantly(More)
Juvenile Strongylocentrotus droebachiensis (average wet weight = 4.0 g) were held at three initial stocking densities (15, 30 and 60 animals per tray, which equates to 0.25, 0.5 and 1 kg sea urchins/m2 surface area, respectively) under constant light and temperature conditions (LD 24:0 and 8.8°C) for 380 days. The somatic growth and survival of the urchins(More)
There has been an increased focus on Salvelinus alpinus as a potential long-term host to Gyrodactylus salaris and, here, both susceptibility to G. salaris and ability to sustain a parasite population seasonally, was tested using fry and parr of S. alpinus from the River Skibotnelva, northern Norway. Fry were highly susceptible. Gyrodactylus salaris survived(More)
This comparative study explores how low temperatures affect the mortality and growth of first generation hatchery-reared progeny of subarctic populations of Arctic charr (Salvelinus alpinus L.) and European whitefish (Coregonus lavaretus L.). Replicate fish groups where held under simulated natural light regimes (70°N) at three constant temperatures (1, 3(More)
Temperature preference of juvenile (age 1+) Arctic charr (Salvelinus alpinus L.) originating from four arctic and sub-arctic populations (Svalbard and mainland northern Norway), representing a range of habitats with different temperature conditions, was studied by use of a shuttle-box system which allowed individual fish to control their environmental(More)
Better knowledge of food search behaviour in fish is essential for studies that aim to improve longline fishing, particularly through bait development. This review provides an overview of our understanding of how fish detect and locate sources of food odour, focusing on the stimuli and sensory modalities involved, and on factors that affect feeding(More)
The Arctic charr (Salvelinus alpinus) is a relatively stenothermal fish that displays a high degree of biological plasticity. Although primarily a freshwater fish, there are anadromous populations at the northernmost limits of the distributional range. Developmental plasticity has both advantages and disadvantages for establishment in culture, with variable(More)
Seasonal growth patterns have been investigated in juveniles of two reproductively isolated Arctic charr [Salvelinus alpinus (L.)] morphs, which coexist in distinct ecological niches (upper-water and deep-water environments) in a subarctic lake. Offspring (F1-generation) of each of the littoral spawning charr (LO) and the profundal spawning charr (PB) were(More)
This article describes the status of the Arctic charr (Salvelinus alpinus L.) aquaculture industry in Iceland, Norway and Sweden. The purpose of the work was to give an update on the status of Arctic charr farming in these countries based on information obtained from the industry itself. The data were collected using questionnaires designed for the purpose(More)
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