Survival and migration speed of radio-tagged Atlantic salmon (Salmo salar) smolts in two large rivers: one without and one with dams

2018 ◽  
Vol 75 (8) ◽  
pp. 1177-1184 ◽  
Author(s):  
Riina Huusko ◽  
Pekka Hyvärinen ◽  
Mikko Jaukkuri ◽  
Aki Mäki-Petäys ◽  
Panu Orell ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Regulated River ◽  
Migration Speed ◽  
Regulated Rivers ◽  
Atlantic Salmon Salmo Salar ◽  
Hydropower Plants ◽  
Similar Survival ◽  
And Migration ◽  
Sea Area

Connectivity problems in fish migration in regulated rivers have been widely studied, but few studies have rigorously compared parallel migration success between regulated and free-flowing rivers. Here, survival and migration speed of downstream migrating radio-tagged Atlantic salmon (Salmo salar) smolts were studied in two large neighboring rivers in the northern Baltic Sea area: one without and one with dams. Both rivers have a free-flowing upper section, where the survival and migration speed of salmon smolts were similar. Survival along the lower section of the free-flowing river was about six times higher than in the lower part of the regulated river with five hydropower plants. Migration speed of smolts was also significantly faster in the river without dams. These severe problems in downstream connectivity in the regulated river pose challenging tasks for restoration of salmon populations.

Implications of temporal and spatial scale for Atlantic salmon (Salmo salar) research

1998 ◽  
Vol 55 (S1) ◽  
pp. 9-21 ◽  
Author(s):  
Carol L Folt ◽  
Keith H Nislow ◽  
Mary E Power
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Multiple Scales ◽  
Spatial Scales ◽  
Effective Means ◽  
Research Strategies ◽  
Atlantic Salmon Salmo Salar ◽  
Temporal And Spatial ◽  
And Migration ◽  
Dependent Processes

The Atlantic salmon (Salmo salar) is a model species for studying scale issues (i.e., the extent, duration, and resolution of a study or natural process) in ecology. Major shifts in behavior and habitat use over ontogeny, along with a relatively long life span and large dispersal and migration distances, make scale issues critical for effective conservation, management, and restoration of this species. The scale over which a process occurs must be linked to the research design and we illustrate this with a discussion of resource tracking by Atlantic salmon. Identifying scale inconsistencies (e.g., when a process is evident at one scale but not another) is shown to be an effective means by which some scale-dependent processes are understood. We review the literature to assess the temporal and spatial scales used in Atlantic salmon research and find most current studies appear to sacrifice spatial and temporal extent for increased resolution. Finally, we discuss research strategies for expanding the temporal and spatial scales in salmon research, such as conducting multiple scales studies to elucidate scale inconsistencies, identifying mechanisms, and using techniques and approaches to generalize across studies and over time and space.

scholarly journals Upstream fishway performance by Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) spawners at complex hydropower dams — is prior experience a success criterion?

2020 ◽  
pp. 1-11
Author(s):  
Anna Hagelin ◽  
Jon Museth ◽  
Larry Greenberg ◽  
Morten Kraabøl ◽  
Olle Calles ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Brown Trout ◽  
Salmo Trutta ◽  
Prior Experience ◽  
Fish Analysis ◽  
Atlantic Salmon Salmo Salar ◽  
Hydropower Plants ◽  
Hydropower Dams ◽  
Brown Trout Salmo Trutta

Passage of hydropower plants by upstream-migrating salmonid spawners is associated with reduced migration success, and the need for knowledge of fish behavior downstream of dams is widely recognized. In this study, we examined fishway passage of landlocked Atlantic salmon (Salmo salar) in River Klarälven, Sweden, and brown trout (Salmo trutta) 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 to 70 days for salmon and 2 to 47 days for trout.

Enriched rearing improves survival of hatchery-reared Atlantic salmon smolts during migration in the River Tornionjoki

2013 ◽  
Vol 70 (9) ◽  
pp. 1386-1395 ◽  
Author(s):  
Pekka Hyvärinen ◽  
Petra Rodewald
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Survival Probability ◽  
Large Scale ◽  
Scale Production ◽  
Migration Speed ◽  
Hatchery Fish ◽  
Large Scale Production ◽  
And Migration ◽  
River Migration

Low survival of stocked fish has been associated with fitness declines of the captive reared fishes because of genetic domestication and unnatural rearing environments. The effects of broodstock origin (wild or captive) or rearing method (standard or enriched) on survival and migration of hatchery-reared Atlantic salmon smolts (Salmo salar) were investigated in the Tornionjoki River using radiotelemetry. Smolts that were reared with enriched methods had a twofold increase in survival (∼38%) compared with smolts that had been reared in a standard hatchery environment (∼19%). Nature-caught smolts had highest survival (∼57%). Smolts from enriched rearing had a higher initial migration speed than fish from standard rearing. Initial migration speed during the first 3 km was positively correlated to survival probability after 290 km for hatchery fish. There was no clear effect of origin on survival or migration speed. The results of this study show that enriching the rearing environment with methods easily applicable to large-scale production promotes smolt survival and migration speed during river migration, which is imperative for stocking success.

Sign in / Sign up

Export Citation Format

Share Document