Search for dissertations about: "stream salmonids"

Showing result 1 - 5 of 7 swedish dissertations containing the words stream salmonids.

  1. 1. Winter behaviour of stream salmonids: effects of temperature, light, and ice cover

    Author : Johan Watz; Larry Greenberg; Eva Bergman; John Piccolo; Svein Jakob Saltveit; Karlstads universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; stream salmonids; winter behaviour; efftect of temperatur; light; ice cover; environment; fish populations; Biology; Biologi;

    Abstract : In boreal streams, stream salmonids typically face low water temperatures and variable ice conditions during winter, and thus stream salmonids are expected to use different behavioural strategies to cope with these environmental conditions. The studies presented in this thesis explore how temperature, light intensity, and surface ice affect salmonid behaviour, with focus on drift-feeding and ventilation rates. READ MORE

  2. 2. Salmonid behaviour under winter conditions

    Author : Johan Watz; Larry Greenberg; Eva Bergman; John Piccolo; Richard Cunjak; Karlstads universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; climate change; drift; energy budget; foraging; grayling; ice cover; lotic; metabolic rate; predation; salmon; stream; stress; temperature; trout; Biology; Biologi;

    Abstract : Winter conditions are believed to play an important role in the population dynamics of northern temperate stream fish, challenging the ability of fish to physiologically and behaviourally adapt. Climate change is predicted to increase both mean temperature and temperature fluctuations, especially during winter, leading to dynamic environmental conditions in terms of river ice production and flow. READ MORE

  3. 3. Effects of fine woody debris on juvenile brown trout (Salmo trutta) and drifting invertebrates

    Author : Åsa Enefalk; Eva Bergman; Siân Griffiths; Karlstads universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; brown trout; juvenile; stream; woody debris; invertebrates; fine woody debris; Biology; Biologi;

    Abstract : In boreal forest streams, woody debris is an important habitat component. Stream invertebrates and salmonids such as brown trout benefit from in-stream wood. READ MORE

  4. 4. From behaviour to genes: anti-predator responses of brown trout (Salmo trutta) under winter conditions

    Author : Karl Filipsson; Eva Bergman; Ann Erlandsson; Martin Österling; Johan Watz; Stefán Óli Steingrímsson; Karlstads universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; burbot; climate change; cortisol; diel behaviour; gene expression; HPI axis; light; mRNA; piscivorous; poikilotherm; predator; salmonid; stream; stress; temperature; thermal; winter behaviour; Biology; Biologi;

    Abstract : Temperature has major effects on the performance of poikilotherms. In encounters with predators, low winter temperatures constrain predator detection and escape capabilities in prey fishes. READ MORE

  5. 5. Pheromonal Mediated Behaviour and Endocrine Responses in Salmonids : The impact of Cypermethrin, Copper, and Glyphosate

    Author : Alia Jaensson; Ingvar Brandt; Håkan Olsen; Kjell Döving; Uppsala universitet; []
    Keywords : MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cypermethrin; copper; glyphosate; behaviour; hormones; pheromones; olfaction; 11-ketotestosterone 11-KT ; 17α; 20β-dihydroxy-4-pregnen-3-one 17; 20β-P ; reproduction; Toxicology; Toxikologi; Biologi med inriktning mot ekotoxikologi; Biology with specialization in Environmental Toxicology;

    Abstract : The effects of cypermethrin, copper and glyphosate on the endocrine system and subsequent response to female pheromones were investigated in mature male brown trout (Salmo trutta) parr.  Responses measured were the amount of strippable milt, blood plasma levels of both an androgen (11-ketotestosterone (11-KT)) and a progestin (17α,20β-dihydroxy-4-pregnen-3-one (17,20b-P)), and behavioural changes. READ MORE