0000000000873768

AUTHOR

Hallvard Jensen

showing 2 related works from this author

Dietary ontogeny and niche shift to piscivory in lacustrine brown trout Salmo trutta revealed by stomach content and stable isotope analyses

2012

The feeding ecology and ontogeny of a large size range of brown trout Salmo trutta in Lake Fyresvatnet, southern Norway, were examined by stomach content and stable isotope analyses. According to the stomach contents, the S. trutta changed their diet at c. 30 cm total length (L(T) ). The smaller size classes fed on benthic invertebrates and surface insects, whereas larger S. trutta (30 cm) fed mainly on whitefish Coregonus lavaretus. A similar, but more gradual shift to piscivory in the size range 25-30 cm was found when using the stable isotope mixing model SIAR to reveal dietary ontogeny. The δ¹³C isotopic signature confirmed that S. trutta independent of size predominantly relied upon be…

Carbon IsotopesFood ChainNitrogen IsotopesbiologyTroutStable isotope ratioEcologyOntogenyZoologyFeeding BehaviorAquatic Sciencebiology.organism_classificationGastrointestinal ContentsPiscivoreDietBrown troutBenthic zonePredatory BehaviorAnimalsSalmoEnergy sourceEcology Evolution Behavior and SystematicsTrophic levelJournal of Fish Biology
researchProduct

Resource Partitioning in Food, Space and Time between Arctic Charr (Salvelinus alpinus), Brown Trout (Salmo trutta) and European Whitefish (Coregonus…

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 trout in the deep and oligotrophic Lake Fyresvatnet, southern Norway (59˚05’N, 8˚10’E). Using CPUE, stomach contents and stable isotope analyses, a distinct resource partitioning was revealed between brown trout and the other two species. Brown trout typically occupied the littoral zone, feeding …

0106 biological sciencesComposite ParticlesTroutlcsh:MedicineMarine and Aquatic Sciences01 natural sciencesBrown troutIsotopesVDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497Salmolcsh:ScienceMultidisciplinarybiologyfood.dishEcologyEcologyNorwayPhysicsStable IsotopescoexistenceFishesPlanktonGastrointestinal ContentsTrophic InteractionsrinnakkaiseloFreshwater FishArctic charrTroutCommunity EcologyOsteichthyesVertebratesPhysical SciencesFreshwater fishEcological NichesSalmonidaeResearch ArticleFreshwater EnvironmentsAtoms010603 evolutionary biologyZooplanktonfoodCoregonus lavaretusAnimalsProfundal zoneParticle PhysicsSalmonidaeEcosystemSalvelinus010604 marine biology & hydrobiologylcsh:REcology and Environmental SciencesOrganismsBiology and Life SciencesAquatic EnvironmentsFeeding BehaviorVDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Marinbiologi: 497Bodies of Waterbiology.organism_classificationInvertebratesLakesFoodEuropean whitefishEarth Sciencesta1181lcsh:Q
researchProduct