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 https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.12685

On 25 October 2022 at 13.15 CET over zoom, Koh Hasegawa will be giving a talk about the ecological effects of invasive salmonids and interactions between hatchery-reared and wild fish in Japan.

Koh Hasegawa

Koh Hasegawa is a Fish Conservation Ecologist working with the Salmon Research Department of the Japan Fisheries Research and Education Agency. Koh in his talk will answer questions about what brown trout do in the urban streams in Sapporo and whether it is a good idea or not to let hatchery-reared and wild population of salmon mix. You are welcome to join this seminar over zoom on Tuesday 25 October at 13:15 CET via https://kau-se.zoom.us/my/kaubiology

Johan Watz (Associate Professor at University of Karlstad Biology Department) together with others from the department, DHI Sverige and Fortum Sverige have recently published an article with VATTEN- Journal of Water Management and Research. The article, entitled ” HOW MUCH WATER DO SEA TROUT NEED? A COMPARISON BETWEEN A CORRELATIVE AND AN INDIVIDUAL-BASED MODEL TO PREDICT EFFECTS OF FLOW ON STREAM FISH POPULATIONS” used both a correlative model and an individual-based fish habitat model called InSTREM 7 as a management tool to assess water requirements for salmon and trout in a river reach located below Blanka-ström hydropower plant in river Emån, Sweden.

To read more about the paper this paper visit https://www.researchgate.net/publication/363272777_Hur_mycket_vatten_behover_havsoringen_En_jamforelse_av_en_korrelativ_och_en_individbaserad_modell_for_att_forutsaga_effekter_av_floden_pa_stromlevande_fiskar

Dr. Mahboobeh Hajiesmaeli, a PostDoc Researcher from Karlstad University’s biology department and a member of the River Ecology and Management (RivEM) group will be giving a talk on how individual-based models (IBMs) of salmonid populations can be used as an effective tool for understanding and managing fish population responses to hydropeaking (hydropower short-term regulation) practices. The main focus is on the first application of an individual-based model, inSTREAM 7.2-SD, to assess the effects of peaking flows on growth, survival and distribution of Atlantic salmon (Salmo Salar) and brown trout (Salmo trutta) in the lower Gullspång River, Sweden. Lilla Åråsforsen (see picture below) was used as the study site for the IBM modeling.

This seminar will be streamed live on zoom on the 21st December at 13.15 (CET) at the link https://kau-se.zoom.us/my/kaubiology

Associate Professor Johan Watz from Karlstad University’s River Ecology Management Research Group (RivEm) and others have recently published a review article entitled Atlantic salmon in regulated rivers: Understanding river management through the ecosystem services lens. The authors synthesized peer-reviewed literature (related to the effects of hydropower on ecosystem services of Atlantic salmon in regulated rivers throughout its native range) to understand how Atlantic salmon conservation has been addressed within the ecosystem services framework. The paper is published open access and can be found at:https://onlinelibrary.wiley.com/doi/full/10.1111/faf.12628


Two current members of NRRV, Larry Greenberg and Eva Bergman, and two former members, Johnny Norrgård and Pär Gustafsson, have recently published an overview of 15 years of research on the endemic, large-bodied population of landlocked River Klarälven-Lake Vänern population of Atlantic salmon (Salmo salar).

They highlight the major findings from studies of each of the salmon’s life stages and conclude that the Klarälven salmon population is below carrying capacity. Greenberg et al. (2021) suggest measures to increase the number of spawners and downstream passage success, and they also recommend habitat restoration to compensate for losses from, for example, former log-driving activities. They also discuss the ecological and legislative problems that need to be addressed if one wishes to re-establish salmon in Klarälven’s upper reaches in Norway. Managing, conserving and conducting research on this migratory salmonid population has been challenging not only because of the ecosystems’ large size, but also because there is more than one anthropomorphic stressor involved.

Read more about the paper here: https://cdnsciencepub.com/doi/full/10.1139/cjfas-2020-0163