Sökning: "Fish Migration"

Visar resultat 1 - 5 av 59 avhandlingar innehållade orden Fish Migration.

1. 1. Downstream migration of salmonids in regulated rivers : Non-conventional methods for fish diversion

   Författare :Johan Leander; Jonatan Klaminder; Micael Jonsson; Gustav Hellström; Paul Kemp; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fish migration; Fish passage; Fish guidance; Hydropower; Atlantic salmon; Brown trout; Bubble barrier; Non-physical barrier;

   Sammanfattning : Passages through hydropower plants can be fatal for downstream migrating salmonids (Salmo spp.). This is particularly true for large adults that are returning to the ocean after spawning. LÄS MER

3. 2. Atlantic salmon in regulated rivers : Migration, dam passage, and fish behavior

   Författare :Daniel Nyqvist; Larry Greenberg; Theodore Castro-Santos; Olle Calles; Scott Hinch; Karlstads universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fish migration; fish passage; downstream migration; kelt; smolt; Biology; Biologi;

   Sammanfattning : Hydropower dams block migration routes and disrupt longitudinal connectivity in rivers, thereby posing a threat to migratory fish species. Various fish passage solutions have been implemented to improve connectivity with varying success. LÄS MER

4. 3. Does fish health matter? The Utility of Biomarkers in Fish for Environmental Assessment

   Författare :Niklas Hanson; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biomarkers; Fish; Environmental monitoring; Ecological risk assessment; Rainbow trout; Perch;

   Sammanfattning : Two common strategies to assess exposure to environmental toxicants are to measure chemical concentrations in the environment and to examine the presence of certain species that are known to be sensit... merive to pollution. LÄS MER

5. 4. Waterfowl in temperate eutrophic lakes - Interactions with macroinvertebrates, submerged vegetation and fish

   Författare :Ola Marklund; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Hydrobiology; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Chara; Asellus; chironomidae; ultraviolet radiation; epiphytes; predation; herbivory; diel vertical migration; fish; Waterfowl; macroinvertebrates; submerged vegetation;

   Sammanfattning : The aim of this thesis was to explore some of the important links between waterfowl and the biota in shallow eutrophic lakes in temperate areas. Waterfowl depend on macroinvertebrates as sources of protein and calcium, which are essential for egg production and growth. Macroinvertebrates in turn depend on submerged vegetation for food and shelter. LÄS MER

7. 5. Large-scale releases of native species : the mallard as a predictive model system

   Författare :Pär Söderquist; Högskolan Kristianstad; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; NATURVETENSKAP; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Anas platyrhynchos; Farmed; Hunting; Introgression; Longevity; Mallard; Migration; Morphology; Population genetic; Restocking; SNPs; Sweden;

   Sammanfattning : Human alteration of natural systems, and its consequences are of great concern and the impact on global ecosystems is one of the biggest threats that biodiversity stands before. Translocations of invasive species, as well as intraspecific contingents with non-native genotypes, whether they are deliberate or unintentional, are one such alteration and its consequences are continuously being assessed. LÄS MER