Article
Ecology
Kim Birnie-Gauvin, Anders Koed, Kim Aarestrup
Summary: The study reveals repeatable individual variation in migration timing and duration in sea trout, with two distinct peaks in return migration timing. Summer-migrating fish have better marine survival but smaller size, while fall-migrating fish have larger size but are exposed to riskier conditions. This suggests a trade-off between size and survival in determining migration strategies.
FUNCTIONAL ECOLOGY
(2021)
Article
Agricultural Engineering
Waseem Hassan, Martin Fore, Henning A. Urke, John B. Ulvund, Eskil Bendiksen, Jo A. Alfredsen
Summary: A novel technique for measuring individual fish swimming speed based on conventional acoustic telemetry and Doppler analysis was tested and proven feasible in a field experiment at a fish farm. The method accurately measures the instantaneous swimming speeds over time for individual fish under commercial farming conditions, and can distinguish between moving and stationary tags.
BIOSYSTEMS ENGINEERING
(2022)
Article
Fisheries
Halvor Kjaeras, Henrik Baktoft, Ana T. Silva, Karl Oystein Gjelland, Finn Okland, Torbjorn Forseth, Marcell Szabo-Meszaros, Olle Calles
Summary: The global population of European eel is declining due to migration barriers in rivers. Bypass solutions are often constructed without sufficient knowledge of swimming behavior. This study used acoustic telemetry to track downstream-migrating silver eels and found differences in swimming behavior between downstream and upstream movement. The study provides important knowledge for designing effective bypass solutions for eels at migration barriers.
JOURNAL OF FISH BIOLOGY
(2023)
Article
Environmental Sciences
Paul G. Thomson, Richard Pillans, Fabrice R. A. Jaine, Robert G. Harcourt, Michael D. Taylor, Charitha B. Pattiaratchi, Dianne L. McLean
Summary: The study indicates that deploying acoustic telemetry equipment around oil and gas platforms may be an effective method for understanding how marine megafauna utilize these structures. Future research should be conducted concurrently with tagging programs to maximize the probability of detecting animals around these structures.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Richard D. Pillans, Wayne Rochester, Russell C. Babcock, Damian P. Thomson, Michael D. E. Haywood, Mathew A. Vanderklift
Summary: The study investigated the movement patterns of lemon sharks using acoustic telemetry along the Ningaloo coast of Australia, revealing longer residency of adults in known nursery areas, with female sharks shifting their core home range further offshore during winter months. Sexual segregation was observed within core areas, with males departing earlier than females. Highly directional and rapid movements correlated with parturition and mating periods were detected, emphasizing the importance of movement data for conservation efforts.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Biology
Julia L. Y. Spaet, Paul A. Butcher, Andrea Manica, Chi Hin Lam
Summary: Understanding the movement and behavior of large marine predators, such as sharks, is crucial for their conservation. By tagging immature white sharks in Australian and New Zealand waters, researchers found that these sharks frequently dive up and down the water column and exhibit different diving behaviors during the day and night.
Article
Environmental Sciences
Richard T. Kraus, H. Andrew Cook, Matthew D. Faust, Joseph D. Schmitt, Mark D. Rowe, Christopher S. Vandergoot
Summary: This study combined acoustic telemetry of fish with water quality modeling to understand the impacts of water quality management on fishery management. The results showed that lake whitefish preferred cooler and more oxygenated habitats in the hypolimnion, and exhibited a strong affinity for the southern shore in eastern Ohio, Pennsylvania, and New York. Expanding lake whitefish habitat and distribution through nutrient reduction could have significant implications for spatial regulation of fishing effort in Lake Erie.
JOURNAL OF GREAT LAKES RESEARCH
(2023)
Article
Fisheries
Rachel Chudnow, Brett van Poorten, Ray Pillipow, Ian Spendlow, Nikolaus Gantner, Scott Hinch
Summary: This study used telemetry and capture-recapture modeling to fill critical information gaps about migratory patterns, distribution, and survival of endangered bull trout in the Upper Fraser River watershed. The results showed that bull trout in this region exhibit repeated long-distance migrations, and the five spawning populations did not differ in their seasonal transition probabilities. The study emphasizes the importance of protecting complex habitats and maintaining natural connections for the conservation of bull trout.
ECOLOGY OF FRESHWATER FISH
(2023)
Article
Fisheries
Linus Lahteenmaki, Panu Orell, Atso Romakkaniemi, Martin Snickars
Summary: This study used radio telemetry to examine the upstream spawning migration behavior of anadromous brown trout in the River Isojoki, western Finland. The results showed that the movement activity of trout during the upstream migration and the location of spawning habitats were influenced by a hydropower dam and flow conditions. These findings highlight the importance of managing flow regimes and improving fishway efficiency to mitigate the negative impacts of climate change on migratory fish populations in boreal river systems.
JOURNAL OF FISH BIOLOGY
(2023)
Article
Ecology
Yuri Niella, Brett Simes, Andrew Fox, Andrew Wright, Matt Waller, Madeline Riley, Lauren Meyer, Michael Drew, Hugh Pederson, Charlie Huveneers
Summary: This study assessed the response of white sharks to research activities and found that external tagging, biopsies, or deterrent trials do not significantly affect the residency and abundance of white sharks. These changes may be part of natural fluctuations rather than a negative response to the research activities.
Article
Acoustics
Tamas Benedek, Janos Vad, Balint Lendvai
Summary: This study investigates the impact of varying sizes of bellmouth entries on tip leakage flow noise of a free inlet - free exhaust axial flow fan, utilizing measurements of inlet velocity profile and CFD simulations to analyze aerodynamic phenomena. The results demonstrate that employing a properly sized bellmouth entry can mitigate tip leakage flow, eliminate double leakage flow, and reduce the emitted noise level by 5-6 dB.
Article
Fisheries
J. Mcilvenny, A. Youngson, B. J. Williamson, N. R. Gauld, L. Goddijn-Murphy, D. Del Villar-Guerra
Summary: The migration of Atlantic salmon smolts from fresh water to the marine environment is a crucial transitional stage in their development. This study used acoustic tracking, instrument data, and hydrodynamic modelling to examine the behavior of juvenile salmon during this transition, finding that migration timing is linked to low-light conditions and tidal currents play a significant role in their movement patterns.
ICES JOURNAL OF MARINE SCIENCE
(2021)
Article
Biodiversity Conservation
Tanner L. Carlson, Lindsey A. P. LaBrie, Jeff S. Wesner, Steven R. Chipps, Alison A. Coulter, Benjamin J. Schall
Summary: This study evaluates the impact of distance, receiver mount design, transmitter depth, and wind speed on the detection probability of acoustic transmitters in a mid-sized river. The results show that detection probability decreases with increasing distance and that mounting the receiver in PVC pipes improves detection probability compared to midriver frames. Additionally, transmitter depth and wind speed also affect detection probability.
ANIMAL BIOTELEMETRY
(2023)
Article
Biodiversity Conservation
Taylor F. Haas, Theodore Castro-Santos, Scott M. Miehls, Zhiqun D. Deng, Tyler M. Bruning, C. Michael Wagner
Summary: This study investigated the tag retention, survival, wound healing, and swim performance of newly transformed sea lamprey implanted with a new micro-acoustic transmitter. The results showed that the survival of tagged lampreys was lower than untagged lampreys, and the mortality was concentrated in the first four days post-surgery. Tagged lampreys swam slower but showed no significant difference in endurance swim tests. Wound healing score was a predictor of swim speed, and wound condition was related to fish mass.
ANIMAL BIOTELEMETRY
(2023)
Article
Fisheries
Mathew G. Wells, Jingzhi Li, Bryan Flood, Yulong Kuai, Jill L. Brooks, Steven J. Cooke, Patricia Semcesen, Jonathan D. Midwood
Summary: Understanding detection range in acoustic telemetry is crucial in fisheries research, especially in lakes with strong seasonal and short-term changes in thermal stratification. Research in Hamilton Harbour, Ontario, Canada, shows that stratification changes significantly affect detection range, with intense internal seiches causing high temporal variability in range.
CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES
(2021)
Article
Marine & Freshwater Biology
Jan G. Davidsen, Linda Eikas, Richard D. Hedger, Eva B. Thorstad, Lars Ronning, Aslak D. Sjursen, Ole K. Berg, Gunnbjorn Bremset, Sten Karlsson, Line E. Sundt-Hansen
Article
Fisheries
Robert J. Lennox, Sindre H. Eldoy, Knut W. Vollset, Kristi M. Miller, Shaorong Li, Karia H. Kaukinen, Trond E. Isaksen, Jan G. Davidsen
JOURNAL OF FISH DISEASES
(2020)
Editorial Material
Fisheries
Knut Wiik Vollset, Robert J. Lennox, Jan Grimsrud Davidsen, Sindre Havarstein Eldoy, Trond E. Isaksen, Abdullah Madhun, Sten Karlsson, Kristina M. Miller
Summary: Salmon farming has become one of the world's major aquaculture species, changing the disease dynamics between farmed and wild salmonids significantly. Low density of fish farms and cold water temperatures in northern regions have limited the impacts of pathogens on wild salmonids, but as interest in fish farming in the north grows and climate change alters ecosystems rapidly, these factors are set to change dramatically.policy considerations related to pathogen dynamics in the north should take into account uncertainties until research questions emerging from imminent changes are fully addressed.
ICES JOURNAL OF MARINE SCIENCE
(2021)
Article
Fisheries
Sindre H. Eldoy, Jan G. Davidsen, Matthias Vignon, Michael Power
Summary: Arctic charr introduced to the Kerguelen Islands have established a self-sustaining population adapted to the unique conditions, with smaller individuals occupying pelagic zones and larger individuals dominating littoral habitats. Although resource-poor, Arctic charr in Kerguelen showed no evidence of cannibalism. Monitoring of this population may provide valuable insights into the adaptability of the species and its responses to ongoing environmental change.
JOURNAL OF FISH BIOLOGY
(2021)
Article
Geography, Physical
Eiliv Larsen, Astrid Lysa, Armann Hoskuldsson, Jan G. Davidsen, Marie J. Nadeau, Michael Power, Georgios Tassis, Stefan Wastegard
Summary: Our study provides the first documentation of tectonic deformation resulting from a volcanic eruption on Jan Mayen Island. By using radiocarbon dating and evidence of shallow magma intrusion, we were able to determine the vertical displacement and uplift around the eruption in around 1732, as well as the impact of the volcanic activity on the surrounding environment.
JOURNAL OF QUATERNARY SCIENCE
(2021)
Article
Fisheries
Tor Atle Mo, Frode Fossoy, Trygve T. Poppe
Summary: Ninety wild Atlantic salmon from the Namsen Fjord near the mouth of River Namsen in mid-Norway were found to have A. simplex larvae in their viscera and muscles, with the intensity of larvae positively correlated with the host's weight and sea age. Female salmon harbored more larvae than males, and the majority of larvae were located in the viscera, particularly in the hypaxial sections anterior to the anus.
JOURNAL OF FISH DISEASES
(2021)
Article
Ecology
S. H. Eldoy, X. Bordeleau, M. J. Lawrence, E. B. Thorstad, A. G. Finstad, F. G. Whoriskey, G. T. Crossin, S. J. Cooke, K. Aarestrup, L. Ronning, A. D. Sjursen, J. G. Davidsen
Summary: This study found that the marine migration behavior of sea trout is influenced by individual nutritional state, sex, and body size, affecting decisions such as migration choice, timing of sea entry, duration of marine residency, and migration distance.
MARINE ECOLOGY PROGRESS SERIES
(2021)
Article
Fisheries
Bengt Finstad, Anne D. Sandvik, Ola Ugedal, Knut W. Vollset, Orjan Karlsen, Jan G. Davidsen, Harald Saegrov, Robert J. Lennox
Summary: This study introduces changes in marine living area and marine feeding time as sustainability indicators for first-time migrant sea trout and develops a method based on a bio-hydrodynamic model to quantify these indicators. The potential impacts of salmon lice on sea trout populations are shown to be significant, greatly influenced by spatial and temporal factors.
AQUACULTURE ENVIRONMENT INTERACTIONS
(2021)
Article
Biology
Kim Birnie-Gauvin, Xavier Bordeleau, Steven J. Cooke, Jan G. Davidsen, Sindre H. Eldoy, Erika J. Eliason, Andy Moore, Kim Aarestrup
Summary: Physiological processes play a critical role in driving life-history strategies in salmonids, impacting energy acquisition and allocation processes which ultimately affect life histories. Studies have shown variation in the role of physiological processes across species and individuals, with consistent results in species with similar life cycles. Despite extensive research on the topic, the study of physiology and its role in determining life-history strategies in salmonids, particularly for char and trout species, remains relatively unexplored.
BIOLOGICAL REVIEWS
(2021)
Article
Multidisciplinary Sciences
Audun H. Rikardsen, David Righton, John Fredrik Strom, Eva B. Thorstad, Patrick Gargan, Timothy Sheehan, Finn Okland, Cedar M. Chittenden, Richard D. Hedger, Tor F. Naesje, Mark Renkawitz, Johannes Sturlaugsson, Pablo Caballero, Henrik Baktoft, Jan G. Davidsen, Elina Halttunen, Serena Wright, Bengt Finstad, Kim Aarestrup
Summary: The study found that the mechanisms driving range-wide reductions in Atlantic salmon marine survival are hindered by a lack of understanding of their oceanic ecology and distribution. The individual salmon migrated further and in different directions than previously reported, showing increased diving activity near oceanographic fronts, highlighting the importance of these regions as feeding areas. Differences in oceanic distribution among individuals and populations may contribute to variations in growth and survival due to environmental conditions.
SCIENTIFIC REPORTS
(2021)
Article
Multidisciplinary Sciences
Jan Grimsrud Davidsen, Xavier Bordeleau, Sindre Havarstein Eldoy, Frederick Whoriskey, Michael Power, Glenn T. Crossin, Colin Buhariwalla, Philippe Gaudin
Summary: The study found that brown trout in the Kerguelen archipelago mainly utilize marine habitats, rarely entering uncolonized watersheds, and have a good nutritional condition, mainly feeding on amphipods and fish. With suitable habitats and rich foraging opportunities, the trout can meet their resource needs close to home, explaining the slowed expansion of brown trout at Kerguelen.
SCIENTIFIC REPORTS
(2021)
Article
Fisheries
Tone Joran Oredalen, Mona Saebo, Tor Atle Mo
Summary: This study detected the presence of T. bryosalmonae in European whitefish for the first time in Norway and provided the first published documentation of the parasite in the kidneys of Arctic charr, brown trout, and whitefish in four lakes. The prevalence of the parasite was higher in brown trout populations compared to Arctic charr and whitefish populations. The presence of the parasite was found in farmed charr but not in wild charr in one lake, indicating a possible link between fish habitat depth and T. bryosalmonae infection.
JOURNAL OF FISH DISEASES
(2022)
Article
Ecology
James D. M. Speed, Ann M. Evankow, Tanja K. Petersen, Peter S. Ranke, Nellie H. Nilsen, Grace Turner, Kaare Aagaard, Torkild Bakken, Jan G. Davidsen, Glenn Dunshea, Anders G. Finstad, Kristian Hassel, Magne Husby, Karstein Harsaker, Jan Ivar Koksvik, Tommy Presto, Vibekke Vange
Summary: The study in Central Norway found that climate change led to decreased abundances of limnic zooplankton and boreal forest breeding birds, as well as earlier plant flowering. However, species distributions and diversity at the regional scale remained largely stable. Surprisingly, the size of ecological responses did not increase with study duration, and shifts in responses did not coincide with shifts in temperature.
ECOLOGY AND EVOLUTION
(2022)
Article
Fisheries
Tor Atle Mo, Haakon Hansen, Sigurd Hytterod
Summary: Gyrodactylus spp. (Monogenea) were found in 16.9% of Arctic char, Salvelinus alpinus (L.), sampled in the Fustvatnet lake, Northern Norway. Two species, G. salaris and G. salmonis, were identified. G. salaris was found only in Arctic char larger than 28 cm and only in samples collected in the autumn. G. salmonis was found in Arctic char of all sizes (11-47 cm) throughout the year, with a peak in abundance in late autumn. G. salaris preferred the tail and dorsal fin. Based on the results, we recommend surveying the fins of large Arctic char sampled during the autumn spawning season for the presence of G. salaris.
JOURNAL OF FISH DISEASES
(2023)
Article
Fisheries
Jan Grimsrud Davidsen, Andrine Emilie Halvorsen, Sindre Havarstein Eldoy, Eva Bonsak Thorstad, Leif Asbjorn Vollestad
Summary: Brown trout and Arctic charr migrated from fresh water to the sea mainly in May and June, with large individual variation in migration timing. Large brown trout migrated earlier than small ones, while no such pattern was found for Arctic charr. Brown trout stayed longer at sea than Arctic charr, and the two species showed differences in their choice of marine areas and feeding strategies. Stable isotope analysis revealed that brown trout fed on marine fish and shrimps, while Arctic charr had a diet with a larger proportion of freshwater invertebrates.
JOURNAL OF FISH BIOLOGY
(2023)