Search for dissertations about: "juveniles"

Showing result 1 - 5 of 48 swedish dissertations containing the word juveniles.

  2. 1. Conservation of landlocked Atlantic salmon in a regulated river : Behaviour of migratory spawners and juveniles

    Author : Anna Hagelin; Eva Bergman; Fleming Ian; Karlstads universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Atlantic salmon; conservation; migration; spawning; hydropower; competition; juveniles; brown trout; hatchery reared; fallback; delay; Biology; Biologi;

    Abstract : 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. READ MORE

  4. 2. Fish Community Structure and the Role of Non-Indigenous Species Associated to Seagrass Ecosystems of Eastern Mediterranean

    Author : Stefan Kalogirou; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Temporal and spatial variation in density, biomass and body size of littoral fish species associated with near shore Posidonia oceanica meadows were studied throughout an annual cycle in an area of eastern Mediterranean. Approximately 109350 littoral fish were collected, belonging to 34 families and 88 species. READ MORE

  5. 3. Differential migration in raptors

    Author : Nils Kjellén; Biodiversitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Osprey; Skua; Population monitoring; Bird migration; Satellite telemetry; Animal ecology; Djurekologi;

    Abstract : Differences between ages, sexes and populations in the timing of migration at Falsterbo, Sweden and in the choice of wintering site among raptors in Scania were investigated. Competition and dominance is the best primary explanation to the results. READ MORE

  6. 4. Effects of size-dependent predation and competition on population and community dynamics

    Author : Karin Nilsson; Lennart Persson; Volker Rudolf; Umeå universitet; []
    Keywords : size-structure; cannibalism; resource competition; predation; emergent facilitation; population regulation; population dynamics; overcompensation; density-dependence; cycles; zooekologi; Animal Ecology;

    Abstract : Most animals grow substantially during their lifetime and change in competitive ability, predatory capacity and their susceptibility to predation as they grow. This thesis addresses the implications of this on regulation and dynamics within populations as well as between population interactions. READ MORE

  7. 5. On ash : a 12-year population ecological study of Fraxinus excelsior L., with special reference to some of its inter-specific interactions, in the deciduous woodland of the outer archipelago of Stockholm

    Author : Per-Göran Tapper; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Fruiting in ash was irregular over the years. Years with abundant fruit production occurred as well as more or less barren years. The resource status of the trees had no decisive influence. READ MORE