Sökning: "fishing mortality"

Visar resultat 1 - 5 av 13 uppsatser innehållade orden fishing mortality.

  1. 1. MODELLING THE SMOLT PRODUCTIVITY OF BROWN TROUT (SALMO TRUTTA) IN HAGA Å

    Kandidat-uppsats, Göteborgs universitet / Instiutionen för biologi och miljövetenskap

    Författare :Lukas Almgren; [2023-10-30]
    Nyckelord :Brown trout; Salmo trutta; Trout habitat score; THS; Haga å; electro-fishing survey;

    Sammanfattning : The brown trout (Salmo trutta) is a facultatively anadromous species, some individuals migrate from the rearing environment in the rivers to the sea while other individuals stay in fresh water. To determine the suitability of a stream for juvenile trout the organization SGBALANST has developed what is called the "Trout habitat score" (THS) model. LÄS MER

  3. 2. Investigating the influence of the tidal regime on harbour porpoise Phocoena phocoena distribution in Mount’s Bay, Cornwall

    Master-uppsats, Lunds universitet/Institutionen för naturgeografi och ekosystemvetenskap

    Författare :Duncan Jones; [2023]
    Nyckelord :Geography; Geographical Information Systems; GIS; Habitat Modelling; Harbour Porpoise; MaxEnt; Tidal Processes; Conservation; Earth and Environmental Sciences;

    Sammanfattning : Investigating the influence of the tidal regime on harbour porpoise Phocoena phocoena distribution in Mount’s Bay, Cornwall Abstract Unintentional by-catch in fishing gear is a significant cause of mortality of harbour porpoises in UK waters. Understanding the spatial distribution of harbour porpoises at fine scales and how this changes over time is essential when trying to understand where these lethal interactions might occur. LÄS MER

  4. 3. Assessment of fish welfare in trawl caught atlantic herring

    Master-uppsats, SLU/Dept. Of Aquatic Resources

    Författare :Mafalda de Leitão Tomás; [2022]
    Nyckelord :welfare; pelagic fisheries; clupea harengus; stress;

    Sammanfattning : With the gain of scientific evidence concerning nociception in fish, the awareness about fish's welfare has been increasing not only for authorities but also for consumers. However, there is still a long way to go concerning how fish are being caught and slaughtered. LÄS MER

  5. 4. Development of northern pike (Esox lucius) populations in the Baltic Sea, and potential effects of grey seal (Halichoerus grypus) predation

    Master-uppsats, SLU/Dept. Of Aquatic Resources

    Författare :Rebecka Svensson; [2021]
    Nyckelord :diet analysis; ; marine mammals; predator-prey; socio-economic; sport fishing; recreational fisheries;

    Sammanfattning : Worldwide, marine mammal populations are increasing after considerable efforts to turn the downward trends caused by hunting, accidental mortality and pollution. The ecosystem effects from the increases of these top predators may be pronounced, but are in most cases poorly known. LÄS MER

  7. 5. The effect of temperature on life history traits of perch (Perca fluviatilis) and its implications for population age- and size structure

    Master-uppsats, SLU/Dept. Of Aquatic Resources

    Författare :Malin Karlsson; [2020]
    Nyckelord :Specific growth; von Bertalanffy growth model; Mortality; Size structure; Size-spectra; Fish; Perch; Perca fluviatilis; Climate change;

    Sammanfattning : The effects of increasing water temperature on key life history traits of fish (e.g. growth rate and maximum body size) have in recent years received considerable attention, but evidence remains inconclusive. LÄS MER