A5088740779- Fish Ecology and Management Studies
- Marine and fisheries research
- Indigenous Studies and Ecology
- Fish Biology and Ecology Studies
- Isotope Analysis in Ecology
- Marine animal studies overview
- Environmental DNA in Biodiversity Studies
- Ecology and biodiversity studies
- Climate Change Communication and Perception
- Wildlife Ecology and Conservation
- Genetic diversity and population structure
- Parasite Biology and Host Interactions
- Aquaculture Nutrition and Growth
- Biomedical Text Mining and Ontologies
- Physiological and biochemical adaptations
- Identification and Quantification in Food
- Aquaculture disease management and microbiota
- Food Industry and Aquatic Biology
- Reproductive biology and impacts on aquatic species
- Aquatic Invertebrate Ecology and Behavior
- Nutrition, Genetics, and Disease
- Research Data Management Practices
- Soil and Water Nutrient Dynamics
- Coral and Marine Ecosystems Studies
- Animal Behavior and Reproduction
Vitensenteret i Trondheim
2016-2025
Norwegian University of Science and Technology
2015-2024
Norsk Teknisk Museum
2014
UiT The Arctic University of Norway
2009-2013
Norwegian Institute for Nature Research
2005-2008
Migration is a widespread but highly diverse component of many animal life histories. Fish migrate throughout the world's oceans, within lakes and rivers, between two realms, transporting matter, energy, other species (e.g. microbes) across boundaries. therefore process responsible for myriad ecosystem services. Many human populations depend on presence predictable migrations fish their subsistence livelihoods. Although much research has focused migration, questions remain in our rapidly...
The biology and ecology of anadromous brown trout (Salmo trutta) at sea is poorly understood. This study provided information on spatial temporal distribution in the ocean. behaviour 115 individuals (veteran migrants, 270–700 mm) was tracked by using acoustic telemetry a fjord system during April–September 2012–2013. Overall, fish spent 68% their marine residence time close to river mouths (<4 km). Most registrations (75%) were nearshore habitats, but pelagic areas also used. maximum...
Abstract This paper reviews the life history of brown trout and factors influencing decisions to migrate. Decisions that maximize fitness appear dependent on size at age. In partly anadromous populations, individuals attain maturity parr stage typically become freshwater resident. For individual fish, is not genetically fixed can be modified by previous growth energetic state in early life. phenotypic plasticity may influenced epigenetic modifications genome. Thus, survival determine...
Determining the mechanisms driving range-wide reductions in Atlantic salmon marine survival is hindered by an insufficient understanding of their oceanic ecology and distribution. We attached 204 pop-up satellite archival tags to post-spawned when they migrated ocean from seven European areas maiden North American captured at sea West Greenland. Individuals further north east than previously reported displayed increased diving activity near oceanographic fronts, emphasizing importance these...
To study smolt behaviour and survival of a northern Atlantic salmon Salmo salar population during river descent, sea entry fjord migration, 120 wild S. were tagged with acoustic tags registered at four automatic listening station arrays in the mouth north Norwegian River Alta throughout Fjord. An estimated 75% post‐smolts survived from mouth, through estuary first 17 km fjord. Survival rates varied fork length ( L F ), ranged 97·0 to 99·5% −1 . On average, spent 1·5 days (36 h, range 11–365...
With the current trends in climate and fisheries, well-designed mitigative strategies for conserving fish stocks may become increasingly necessary. The poor post-release survival of hatchery-reared Pacific salmon indicates that enhancement programs require assessment. objective this study was to determine relative roles genotype rearing environment play phenotypic expression young salmon, including their survival, growth, physiology, swimming endurance, predator avoidance migratory...
The migratory behaviour and spatial area use of sympatric Arctic charr Salvelinus alpinus brown trout Salmo trutta were investigated during their marine feeding migration. likelihood finding individuals both species in the inner or outer fjord areas was dependent on water temperature (especially for S. ), difference between ) fish fork length (both species). strongest predictor area, particularly left this moved to with increasing temperatures area. At 8° C >50%. This had a smaller effect...
This paper explores the ecosystem services provided by anadromous brown trout (often termed sea trout) populations in Norway. Sea is an important species both freshwater and marine ecosystems provides demand-driven ecological provisioning socio-cultural services. While once service through a professional fishery subsistence fishing, fishing for near shore coastal areas rivers today very popular accessible recreational activity generates primarily The contributes to local cultural heritage,...
ABSTRACT Pathogens play a key role in individual function and the dynamics of wild populations, but link between pathogens performance has rarely been investigated wild. Migrating salmonids offer an ideal study system to investigate how infection with affects given that climate change fish farming portend increasing prevalence populations. To test for effects pathogen burden on migrating salmonid, we paired data from brown trout tagged acoustic accelerometer transmitters gill biopsies...
Habitat is a powerful force in ecosystems, and the quantity quality of habitat can shape ecosystem structure function. Among many important roles that plays as mediator ecological interactions, including predator–prey dynamics. In context restoration, there great potential to better understand how dynamics are influenced by whether this has implications for ecosystems managed. We consider ways which serves an interactions between predators their prey present four acts intermediary enhances...
Eight hatchery‐reared Atlantic salmon Salmo salar post‐smolts, implanted with acoustic depth sensing transmitters and manually tracked for 5–12 h in the Hardangerfjord (Norway), spent most of their time (49–99%) at 1–3 m during day, whereas four seven fish were found close (<0·5 m) to surface night, a strong negative cross‐correlation between general swimming light intensity. Hence, actual post‐smolts early marine migration may depend on conditions, although individual variation vertical...
Abstract The migratory behaviour of hatchery‐reared Atlantic salmon, Salmo salar L., post‐smolts during the first phase marine migration was examined to assess their susceptibility salmon lice, Lepeophtheirus salmonis (Krøyer), infestations. Swimming depths eight relative measured salinity and temperature were monitored for an average 11.4 h following release outside mouth River Eio using depth sensitive acoustic transmitters. Vertical distributions simultaneously recorded along route. Mean...
Atlantic salmon (Salmo salar) often survive spawning and migrate back to the sea feed, either shortly after in autumn or following spring. We conducted a 4-year observational field study using telemetry evaluate determinants of migration timing postspawners (kelts). found that individuals with low energy reserves migrated early risky but productive marine habitat, whereas greater stayed safe less river habitat until staying became energetically more costly than migrating. For males,...
The early migration and habitat use of brown trout Salmo trutta post‐smolts tagged with acoustic transmitters ( n = 50) were investigated in a fjord system central Norway from 30 April to 26 November 2014. main aims investigate return rate, marine residence time spatial the system. Median seaward fresh water dates 22 May 4 July, respectively. Of 40 migrating smolts, returned water, giving minimum rate 65%. Entrance river occurred mainly at night (80% S. ), however, no such diurnal pattern...
Airguns used for offshore seismic exploration by the oil and gas industry contribute to globally increasing anthropogenic noise levels in marine environment. There is concern that omnidirectional, high intensity sound pulses created airguns may alter fish physiology behaviour. A controlled short-term field experiment was performed investigate effects of exposure from a airgun on behaviour two socioeconomically ecologically important fishes: Atlantic cod (Gadus morhua) saithe (Pollachius...
Abstract Acoustic telemetry (AT) has emerged as a valuable tool for monitoring aquatic animals in both European inland and marine waters over the past two decades. The Tracking Network (ETN) initiative played pivotal role promoting collaboration among AT researchers Europe led to significant increase number of tagged observed transboundary waters. While benefits decision‐making delivers essential data management bodies, its potential mechanisms yet be fully harnessed. We reviewed existing...
The brown trout (Salmo trutta) is an iteroparous, anadromous salmonid that exhibits a complex continuum of feeding migration tactics, ranging from freshwater residency, to potamodromy, estuarine migration, as well short- long-distance coastal migrations. While migrants are believed play important role in the species’ population dynamics, little known about factors driving differences extent individual marine habitat use. In this study, 32 veteran were acoustically tagged prior their seaward...
The aim of this study was to test the hypothesis that hatchery brown trout Salmo trutta smolts, with 50% reduced or no feeding over last 5 months before release, were more likely migrate sea than individuals standard ratios. juvenile fish divided into three groups 176 days release: (A) feeding, (B) and (C) 100% feeding. To their seaward migration, 40 from each group tagged acoustic transmitters tracked by automatic listening stations in River Nidelva, Trondheim, Norway, its estuary nearest...
The vertical behaviour of 44 veteran sea trout Salmo trutta (275-580 mm) in different marine fjord habitats (estuary, pelagic, near shore with and without steep cliffs) was documented during May-February by acoustic telemetry. swimming depth S. influenced habitat, time day (day v. night), season, seawater temperature the body length at tagging. Mean May-September 1·7 m (individual means ranged from 0·4 to 6·4 m). Hence, were generally surface oriented, but performed dives down 24 m. deeper...
The sea trout (anadromous brown Salmo trutta ) displays extensive among-individual variation in marine migration behaviour. We studied the behaviour of 286 (27-89 cm) tagged with acoustic transmitters spring, 7 populations located 2 distinct fjord systems Norway. examined whether individual nutritional state, sex and body size influenced terms (1) decision to migrate or remain resident freshwater and/or estuarine habitats, (2) seasonal timing entry, (3) duration residency (4) distance at...
To study the migratory behaviour in wild northern European silver eel Anguilla anguilla during sea entry and early marine migration, 32 individuals were tagged with acoustic transmitters registered at four automatic listening station arrays from mouth of north Norwegian River Alta throughout Fjord. The A. entered fjord all parts tidal cycle did not seem to utilize outgoing currents. They migrated mainly night, both river fjord. On average, they spent 2·7 days travelling outermost array, 31...
Little is known about Atlantic salmon behaviour during the last phase of marine homing migration and subsequent river entry. In this study, 56 adult in Alta Fjord northern Norway were equipped with acoustic transmitters. Salmon generally followed coastline, but their horizontal distribution was also affected by wind-induced spreading water across fjord. Mean swimming depth shallow (2.5–0.5 m), dives down to 30 m depth. Timing entry not flow, diel periodicity, or tidal cycles. Movements part...