Sökning: "Predation"

Visar resultat 16 - 20 av 253 avhandlingar innehållade ordet Predation.

  1. 16. Behaviour under predation risk - antipredator strategies, behavioural syndromes and sex-specific responses in aquatic prey

    Författare :Sanna Harris; Biodiversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; phenotypic integration; Poecilia reticulata; Asellus aquaticus; behavioural syndromes; chemical cues; predation; antipredator behaviour;

    Sammanfattning : In many natural ecosystems, predation is well recognized as a strong evolutionary force, and predator-mediated selection has been demonstrated to induce changes in prey morphology, life history and behaviour. In my thesis, I have focused on behavioural responses in aquatic prey under the risk of predation. LÄS MER

  3. 17. Long Term Studies of Insect Abundances in Temporary Wetlands in Relation to Hydrology, Predation and Bti

    Författare :Thomas Persson Vinnersten; Jan O Lundström; Örjan Östman; William Walton; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; floodwater mosquitoes; mosquito control; predation; aquatic insects;

    Sammanfattning : Long-term insect abundances have been studied to investigate factors structuring the insect communities of the temporary wetlands around the River Dalälven floodplain. In the wet meadows and swamps in the River Dalälven floodplains recurrent floods are the ultimate prerequisite for high production of floodwater mosquitoes. LÄS MER

  4. 18. Environmental factors selecting for predation resistant and potentially pathogenic bacteria in aquatic environments

    Författare :Peter Mathisen; Agneta Andersson; Johanna Thelaus; Mats Forsman; Anders Sjöstedt; Tron Frede Thingstad; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Eutrophication; productivity; predation pressure; predation-resistant bacteria; pathogens; Francisella tularensis; adaptation; biomarker; oligotyping;

    Sammanfattning : The long history of co-existence of bacteria and their protozoan predators in aquatic environments has led to evolution of protozoa resistant bacteria (PRB). Many of these bacteria are also pathogenic to humans. LÄS MER

  5. 19. Zooplankton responses to multiple threats within and across generations

    Författare :Yongcui Sha; Enhet akvatisk ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Predation; Ultraviolet radiation; Daphnia; copepods; plasticity; maternal effects; adaptation; diel vertical migration;

    Sammanfattning : In their natural environments, organisms are unlikely to be distributed randomly but instead they are constantly faced with multiple and variable threats. In order to maximise survival, they need to be able to perceive the present threat level and respond accordingly. LÄS MER

  7. 20. Pikeivory: behavioural mechanisms in northern pike piscivory

    Författare :Anders Nilsson; Enhet akvatisk ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; northern pike; cannibalism; kleptoparasitism; predation; optimal foraging; Animal ecology; Djurekologi;

    Sammanfattning : Optimal foraging and prey preference in top predators may affect population and community dynamics and structure. Also, optimal foraging and prey preference may shift with prevailing conditions, and therefore create changes in the effect of predation. LÄS MER