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PARASITES FAUNA OF THE LAKE KRONOTSKOE CHARRS (SALVELINUS), KAMCHATKA
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016)
The new data on the parasites fauna of the Lake Kronotskoe sympatric charr forms (genus
Salvelinus (Nilsson) Richardson, 1836) is presented. Parasites fauna of Bigmouth and
Smallmouth charr forms are described for the first time. The information about Longhead
charr, Nosed charr and White charr parasites is added. 29 species of parasites from 9 classes
were found: Oligohymenophorea, Myxosporåà, ...
Histopathological characterisation of retinal lesions associated to Diplostomum species (Platyhelminthes: Trematoda) infection in polymorphic Arctic charr Salvelinus alpinus
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018)
The eye represents an immune privileged organ where parasites can escape host reactions. This study provides the first systematic evidence of the pathology associated with <i>Diplostomum</i> sp. infection in the eye retina of fish (i.e. Arctic charr). Histological sections showed that the trematodes caused mechanical disengagement between the retinal pigmentary epithelium and the neurosensory retina, ...
Røye som langtidsvert og smittereservoar for Gyrodactylus salaris i Skibotnelva i Troms
(Research report; Forskningsrapport, 2005-03)
Skibotnelva i Troms var lenge det eneste vassdraget i våre to nordligste fylker med infeksjon av fiskeparasitten Gyrodactylus salaris. Parasitten ble første gang påvist i 1979, og to rotenonbehandlinger i den lakseførende delen (i 1988 og 1995) har vært mislykkede. Di-rektoratet for naturforvaltning vurderer bygging av langtidssperre som et av flere aktuelle utryddingstiltak i Skibotnelva. Imidlertid ...
Parasitism and the Biodiversity-Functioning Relationship
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-02-15)
Species interactions can influence ecosystem functioning by enhancing or suppressing the activities of species that drive ecosystem processes, or by causing changes in biodiversity. However, one important class of species interactions – parasitism – has been little considered in biodiversity and ecosystem functioning (BD-EF) research. Parasites might increase or decrease ecosystem processes by ...
New parasites and predators follow the introduction of two fish species to a subarctic lake: implications for food-web structure and functioning
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
Introduced species can alter the topology of food webs. For instance, an introduction can aid the arrival of free-living consumers using the new species as a resource, while new parasites may also arrive with the introduced species. Food-web responses to species additions can thus be far more complex than anticipated. In a subarctic pelagic food web with free-living and parasitic species, two fish ...
Resource Partitioning in Food, Space and Time between Arctic Charr (Salvelinus alpinus), Brown Trout (Salmo trutta) and European Whitefish (Coregonus lavaretus) at the Southern Edge of Their Continuous Coexistence
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017)
Arctic charr and European whitefish are considered to be strong competitors in lakes, with the latter usually being the superior species. However, high niche plasticity and lake morphometry may suggestively facilitate resource partitioning and coexistence between charr and whitefish. Here, we explore the trophic niche utilization (diet and habitat use) of charr and whitefish co-occurring with brown ...
Trophic niche similarity among sea trout Salmo trutta in Central Norway investigated using different time-integrated trophic tracers
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-21)
From 2011 to 2013, anadromous brown trout Salmo trutta (213−730 mm, total body
length, LT) were collected during or shortly after their marine feeding migration at 7 different
localities in central Norway. The mean volume of stomach content (%) of marine fish prey eaten
by S. trutta captured in marine waters varied from 34 to 89%. There was a high prevalence
(67−100%) for parasite groups potentially ...
Allometric trajectories of body and head morphology in three sympatric Arctic charr (Salvelinus alpinus (L.)) morphs
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-08)
A study of body and head development in three sympatric reproductively isolated Arctic charr (Salvelinus alpinus (L.)) morphs from a subarctic lake (Skogsfjordvatn, northern Norway) revealed allometric trajectories that resulted in morphological differences. The three morphs were ecologically assigned to a littoral omnivore, a profundal benthivore and a profundal piscivore, and this was confirmed ...
The trade-off between fecundity and egg size in a polymorphic population of Arctic charr (Salvelinus alpinus (L.)) in Skogsfjordvatn, subarctic Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-02-26)
Reproductive traits differ between intralacustrine Arctic charr morphs. Here, we ex
-
amine three sympatric lacustrine Arctic charr morphs with respect to fecundity, egg
size and spawning time/site to assess reproductive investments and trade-
offs, and
possible fitness consequences. The littoral omnivore morph (LO-
morph) utilizes the
upper water for feeding and reproduction and spawn ...
Parallel and non-parallel morphological divergence among foraging specialists in European whitefish (Coregonus lavaretus)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
Parallel phenotypic evolution occurs when independent populations evolve similar traits in response to similar selective regimes. However, populations inhabiting similar environments also frequently show some phenotypic differences
that result from non-parallel evolution. In this study, we quantified the relative importance of parallel evolution to similar foraging regimes and nonparallel lake-specific ...