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Feeding ecology of piscivorous brown trout (Salmo trutta L.) in a subarctic watercourse
(Journal article; Tidsskriftartikkel; Peer reviewed, 2004-02)
Feeding ecology of piscivorous brown trout was studied in the Pasvik watercourse, Norway and Russia. The watercourse is heavily regulated for hydroelectric purposes, and 5000 brown trout > 25 cm are stocked annually to compensate the negative impacts of the impoundments. Stocked and wild trout had almost identical diets consisting mainly of vendace Coregonus albula and partly of whitefish Coregonus ...
Long-term responses of zooplankton to invasion by a planktivorous fish in a subarctic watercourse
(Journal article; Tidsskriftartikkel; Peer reviewed, 2008-08-13)
<p>1. Introduced or invading predators may have strong impacts on prey populations of the recipient community mediated by direct and indirect interactions. The long‐term progression of predation effects, covering the invasion and establishment phase of alien predators, however, has rarely been documented.</p>
<p>2. This paper documents the impact of an invasive, specialized planktivorous fish ...
On the numerous concepts in invasion biology
(Journal article; Tidsskriftartikkel; Peer reviewed, 2006-01-20)
The study of biological invasions has triggered the production of a diversity of concepts. The terminology has, however, often been applied inconsistently and inaccurately. This article lists and assesses the most commonly used terms and concepts in invasion ecology. In each case the most coherent definition and use is suggested.
Planktivore vertical migration and shoaling under a subarctic light regime
(Journal article; Tidsskriftartikkel; Peer reviewed, 2009-03-20)
Visually foraging planktivorous fish are prey of visual predators, and their foraging behaviour may be affected by light levels both in terms of gain and risk. The large seasonal change in day length throughout a subarctic summer at 69°N was used to show the influence of light on diel vertical migration (DVM) and shoaling patterns in a planktivorous fish assemblage consisting of two species (<i>Coregonus ...
Demographic responses of Daphnia magna fed transgenic Bt-maize
(Journal article; Tidsskriftartikkel; Peer reviewed, 2009-10-27)
The food/feed quality of a variety of genetically modified (GM) maize expressing Cry1Ab Bt-toxin was tested over the life-cycle of <i>Daphnia magna</i>, an arthropod commonly used as model organism in ecotoxicological studies. Demographic responses were compared between animals fed GM or unmodified (UM) near isogenic maize, with and without the addition of predator smell. Age-specific data on survival ...