Migration of adult salmon and sea trout in Norwegian rivers
1 Purpose:
Ecology of salmonids in lakes and the impacts of hydropower on their habitat is a pressing question. Our team has secured projects for tracking adult salmon and sea trout in rivers in Norway including Vosso, Aurland and Storelva using acoustic and radio telemetry. The goal of this project is to observe how the migration of these salmonids is impacted by hydropower as they reside in the lake. The study is targeted to fill out the knowledge gaps outlined in:
Lennox, R. J., Pulg, U., Malley, B., Gabrielsen, S. E., Hanssen, E. M., Cooke, S. J., ... & Vollset, K. W. (2021). The various ways that anadromous salmonids use lake habitats to complete their life history. Canadian Journal of Fisheries and Aquatic Sciences, 78(1), 90-100.
2 Distress:
Our team has years of experience capturing, handling, and tagging adult salmon and sea trout for telemetry research. We use procedures that are appropriate for these fish and globally validated methods for fish tracking. Our work entails capture, anesthesia, biopsy, tagging, and release back to the wild. We have recaptured fish after tagging and observed good healing. Our tracking data indicates high survival of these fish and good data. The overall procedure represents a moderate stress level, which is mitigated by following standard operating procedures for working at appropriate water temperatures and using methods that maximize our ability to care for the fish and identify adverse reactions to proceed in a welfare-enlightened way (SOP 6, SOP 12.E ).
3 Expected benefit:
Understanding the impact of hydropower on lake use of salmonids is of great interest to management of salmonids in regulated rivers. A third of all Norwegian rivers with anadromous salmon and trout have lakes which is an understudied habitat for salmonids. Impacts on these key overwintering areas are particularly pressing, and will make it possible to design mitigation to minimize impacts of salmon and trout in the wild.
4 Number of animals, and what kind:
In total 200 adult salmon and 200 adult trout will be tagged with acoustic tags following standard operating procedures (SOP 6, SOP 12.E).
5 How to adhere to 3R:
We have little knowledge about the behavior of these animals in lakes and spatial temporal behavior in lakes can only be studied using telemetry. The exact number that is needed to model the spatial temporal behavioral patterns (including temperature preference, activity levels, and fine scale behavior) related to hydropower operations is unknown, but using experience from earlier studies in dialogue with Professor Steven Cooke at Carleton University, we expect that approximately 50 individuals per species per experimental year is likely to be an appropriate balance between number of research animals and getting data that is necessary to get data that be can used in scientific studies.
Ecology of salmonids in lakes and the impacts of hydropower on their habitat is a pressing question. Our team has secured projects for tracking adult salmon and sea trout in rivers in Norway including Vosso, Aurland and Storelva using acoustic and radio telemetry. The goal of this project is to observe how the migration of these salmonids is impacted by hydropower as they reside in the lake. The study is targeted to fill out the knowledge gaps outlined in:
Lennox, R. J., Pulg, U., Malley, B., Gabrielsen, S. E., Hanssen, E. M., Cooke, S. J., ... & Vollset, K. W. (2021). The various ways that anadromous salmonids use lake habitats to complete their life history. Canadian Journal of Fisheries and Aquatic Sciences, 78(1), 90-100.
2 Distress:
Our team has years of experience capturing, handling, and tagging adult salmon and sea trout for telemetry research. We use procedures that are appropriate for these fish and globally validated methods for fish tracking. Our work entails capture, anesthesia, biopsy, tagging, and release back to the wild. We have recaptured fish after tagging and observed good healing. Our tracking data indicates high survival of these fish and good data. The overall procedure represents a moderate stress level, which is mitigated by following standard operating procedures for working at appropriate water temperatures and using methods that maximize our ability to care for the fish and identify adverse reactions to proceed in a welfare-enlightened way (SOP 6, SOP 12.E ).
3 Expected benefit:
Understanding the impact of hydropower on lake use of salmonids is of great interest to management of salmonids in regulated rivers. A third of all Norwegian rivers with anadromous salmon and trout have lakes which is an understudied habitat for salmonids. Impacts on these key overwintering areas are particularly pressing, and will make it possible to design mitigation to minimize impacts of salmon and trout in the wild.
4 Number of animals, and what kind:
In total 200 adult salmon and 200 adult trout will be tagged with acoustic tags following standard operating procedures (SOP 6, SOP 12.E).
5 How to adhere to 3R:
We have little knowledge about the behavior of these animals in lakes and spatial temporal behavior in lakes can only be studied using telemetry. The exact number that is needed to model the spatial temporal behavioral patterns (including temperature preference, activity levels, and fine scale behavior) related to hydropower operations is unknown, but using experience from earlier studies in dialogue with Professor Steven Cooke at Carleton University, we expect that approximately 50 individuals per species per experimental year is likely to be an appropriate balance between number of research animals and getting data that is necessary to get data that be can used in scientific studies.