Jenni Prokkola

On Tuesday 8 November, at 13:15 CET Jenni Prokkola from Academy Research Fellow, Natural Resources Institute (Luke), Finland will be giving a talk about The energetics of life-history variation in Atlantic salmon: a question of resource allocation and genetic constraints. Pioneering genetic association studies have identified genomic regions strongly linked to the enormous life-history variation found in Atlantic salmon (Salmo salar). Jenni will describe how she uses genomic prediction in follow-up empirical studies to test if life history variation in salmon may be constrained by whole animal and tissue-level energetic pathways.

The seminar will be held at Karlstad University House 21, room 349, and also live on zoom at ( You are invited to physically attend this seminar at Karlstad University campus building 21 or live on zoom.

Louis Addo (Ph.D. Student at Karlstad University)

Louis Addo (Doctoral Student), Mahboobeh Hajiesmaeli (Post-doctoral Researcher), John Piccolo (Professor) and John Watz (Associate Professor in Biology) all from the River Ecology and Management Research Group RivEM, Department of Environmental and Life Sciences at Karlstad University have recently published a paper entitled “Growth and mortality of sympatric Atlantic salmon and brown trout fry in fluctuating and stable flows” with the journal Ecology of Freshwater Fish.

In their paper, they explore the potential effects of hydropeaking or short-term regulated rivers on the growth and mortality of sympatric Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) at the fry life stage.

This paper is open-access and can be found at

Professor Larry Greenberg, NRRV, and William Ardren, US Fish & Wildlife Service, have co-edited a special issue on nonanadromous Atlantic Salmon in the Canadian Journal of Fisheries and Aquatic Sciences. The issue is entitled “Conservation, Ecology, and Evolution of Nonanadromous Atlantic Salmon” and has contributions from experts from North America and Europe, consisting of 13 papers. The papers cover four themes, namely (1) ecology, evolution, and behavior, (2) conservation and management (3) improving hatchery programs and (4) re-introduction efforts. Three of the papers come from NRRV researchers;




Larry Greenberg and William Ardren have written a general overview of the 13 papers in a paper entitled ‘Introduction to “Conservation, Ecology, and Evolution of Nonanadromous Atlantic Salmon”. This can be found at:

Brown trout (Salmo trutta) eggs with eyed embryos

On Tuesday 8 December Kalle Filipsson, RivEM PhD student, will present his work on how elevated temperatures and predator presence during egg incubation affect development and behaviour of brown trout. The seminar starts at 13:15 and will be streamed live on Zoom. Contact Kalle ( if you are interested in attending the seminar, and he will send you a link.

Rachel Bowes (RivEM PostDoc) and colleagues have studied the downstream passage of several migrating fish species during spring and fall 2020. Here she writes about their work:

Laxeleratorn at Vattenfall’s Research & Development facility in Älvkarleby

“Dams are like giant road blocks for fish in rivers. It is not always feasible or realistic to remove a dam to restore fish movement throughout rivers, so we need to design detours around them.

When going downstream we call this detour past the dam a bypass. The question we are asking is: How can we design a better bypass for multiple fish species to be able to move downstream past a dam more easily and efficiently? To test this, we are using the Laxeleratorn at Vattenfall’s Research & Development facility in Älvkarleby. We are testing Silver Eels, Salmon, and Roach fish species. Changing the design of the bypass and amount of water flowing through it, we hope to find out what combination creates the optimal bypass for these fish species.”

European eel (Anguilla anguilla)

On tuesday 27 October (tomorrow) Patrik Andreasson (Adjunct Professor, Luleå University of Technology; Specialist, Vattenfall AB) will give a seminar titled “Fish diagnostics by image recognition using machine learning (AI)”.

The seminar starts at 13:15 and will be held via zoom. Everyone who wants to are welcome to attend the seminar. Contact Olle Calles ( to receive a zoom link to the seminar.

Image recognition using AI, as a tool for fish identification, was mentioned on the Swedish news earlier this year. Follow this link to to watch a short video and to read more about the project (in Swedish).

Our former PhD student Anna Hagelin and several other researchers, amongst them Larry Greenberg, Olle Calles and Eva Bergman, recently published a new paper in the Canadian Journal of Fisheries and Aquatic Sciences.

They examined fishway passage of landlocked Atlantic salmon in River Klarälven, Sweden and brown trout in River Gudbrandslågen, Norway, and the influence of prior experience on passage success in 2012 and 2013. Fishway trap efficiency varied from 18 to 88% and was influenced by river discharge. Most salmon (81%) entered the fishway trap on days without spill, and salmon moved from the turbine area to the spill zone when there was spill, with small individuals showing a stronger reaction than large fish. Analysis of fish with and without prior trap experience showed that a higher percentage of the “naïve” fish (70% of salmon and 43% of the trout) entered the fishway traps than the “experienced” ones (25% of the salmon and 15 % of the trout). Delays for fish that entered the trap ranged from 3-70 days for salmon and 2-47 days for trout.

The paper is not publicly accessible, but can be requested via ResearchGate.

On Thursday 26 March, Kristine Lund Bjørnås, NRRV PhD-student, will defend her licentiate thesis “Modeling Atlantic salmon and brown trout responses to river habitat alteration”. The defense starts at 10:00. Asbjørn Vøllestad, Professor at the University of Oslo, is the opponent for Kristine’s defense.

Kristine’s defense will be held as an online meeting on Zoom (a video communication system commonly used by universities). You should be able to follow Kristine’s defense using this link:

The defense will also be streamed live on a bigscreen in lecture hall 1B309 (Sjöströmsalen) at Karlstad University, and everyone is welcome to watch the defense from the lecture hall. Please note that Kristine and the opponent will not be in the lecture hall.

On Tuesday 10 March, Kristine Lund Bjørnås, PhD student at Karlstad University, will give a seminar entitled “Modeling Atlantic salmon and brown trout responses to river habitat alteration”. The seminar starts at 13.15 in room 5F416, everyone who wants to is welcome to attend the seminar.

This seminar is a practice seminar in preparation for Kristine’s licentiate defense, which will be held Thursday 26 March at 10:00. More information about the licentiate seminar will be provided closer to the defense.

Kristine Lund Bjørnås and Niclas Carlsson taking point measurements of the physical habitat in Gullspångsforsen.

Anna Hagelin and the opponent Professor Ian Fleming, Memorial University of Newfoundland, Canada, at Anna’s PhD defense

Anna Hagelin successfully defended her PhD thesis with the title “Conservation of landlocked Atlantic salmon in a regulated river: Behaviour of migratory spawners and juveniles12 April this year.

Anna also presented her research at “forskningspodden” (the research podcast), which is a popular science podcast at Karlstad University. Here you can listen to Anna talk about her research on salmon conservation in river Klarälven (in Swedish).