Sökning: "ANADROMOUS"

Visar resultat 1 - 5 av 9 avhandlingar innehållade ordet ANADROMOUS.

  1. 1. Migration in anadromous brown trout

    Författare :David Aldvén; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Downstream migration; Temperature; Discharge; Genetics; Growth rate; Climate change; Salmo trutta; Salmo salar; Sea trout; Salmon; Biology; Ecology;

    Sammanfattning : This thesis investigates the anadromous migration of brown trout (Salmo trutta) with the overall aim to improve stock management within the region. Several field studies were conducted in different streams and coastal areas on the west coast of Sweden specifically aimed to evaluate environmental triggers for migration (Paper I), migration pathways and strategies (Paper III and IV) as well as the genetic differentiation of anadromous populations of brown trout (Paper V). LÄS MER

  3. 2. Anadromous Pike in the Baltic Sea

    Författare :Olof Engstedt; Per Larsson; Henrik Svedäng; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Marine ecology; Marin ekologi; Natural Science; Naturvetenskap;

    Sammanfattning : The pike (Esox lucius) is a major predator and top-down regulator in the Baltic Sea where it exists in two sympatric forms. One spawn in streams and rivers and the other one spawn in the sea. During the last decades, the habitats for both of these forms have developed in a negative way. LÄS MER

  4. 3. Temporal relationships between fish-eating birds and their prey in a north Swedish river

    Författare :Kjell Sjöberg; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Seasonal and diel activity; food consumption; predator-prey relationships; fish-eating birds; anadromous fish; Mergus merganser; M. serrator; Sterna spp.; Larus spp.; Lampetra fluviatilis; Gasterosteus aculeatus;

    Sammanfattning : The seasonal and diel feeding habits of the goosander, Mergus merganser, the red-breasted merganser, M. serrator, gulls (Larus canus, L. argentatus and L. fuscusj and terns, Sterna hirundo/paradisaea were studied at 64V05'N. LÄS MER

  5. 4. Size-dependent predator-prey interactions, distribution and mortality in salmon: effects on individuals and populations

    Författare :Philip Jacobson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The biomass dynamics of populations is largely determined by the survival, growth, and reproduction of individuals. For fish and other animals, survival, growth, and reproduction depends on the amount of energy an individual obtains via feeding and are therefore food-dependent. LÄS MER

  7. 5. Gonad and ejaculate allocation in alternative reproductive tactics of salmon and trout with reference to sperm competition

    Författare :Tomislav Vladić; Michael Taborsky; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; alternative reproductive tactics; sperm competition; brown trout; Atlantic salmon; ATP; ejaculate expenditure; motility; sperm morphology; trade-off; loaded raffle; zoologi; Zoology;

    Sammanfattning : Atlantic salmon, Salmo salar L., and brown trout, Salmo trutta L., exhibit alternative male maturation phenotypes, anadromous and precociously mature parr, which commonly endure in sperm competition at the spawning grounds. LÄS MER