Restored river habitat provides a natural spawning area for a critically endangered landlocked Atlantic salmon population

Certain spawning areas of the critically endangered Lake Saimaa landlocked Atlantic salmon (Salmo salar m. sebago) have been recently restored by excavator- and helicopter-scattered gravel, but the success of applied methodologies has remained open. Here, we monitored the spawning-related movements and redds occurrence of transported semi-wild and hatchery-reared salmon in the restored River Ala-Koitajoki, Eastern Finland using radiotelemetry and snorkelling. Nearly all fish accepted the newly-restored spawning habitats in the river that maintains a low flow rate (only 4 m3 s-1). The movements of females released up to two weeks before spawning time were restricted mainly to the closest rapids from the release site, and most of the movements were directed downstream. Semi-wild and hatchery background fish exhibited similar mobility, which was more variable among males. A majority of redds were found in restored areas, and both helicopter- and excavator-scattered gravels were accepted as spawning substrates. Our results indicate that natural reproduction of the studied landlocked salmon population can be successfully returned to its original spawning river by restoration of habitats and transfer of spawners.

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River Spawning of Artificially Reconditioned Atlantic Salmon (Salmo salar)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f89-103 ◽

1989 ◽

Vol 46 (5) ◽

pp. 824-826 ◽

Cited By ~ 6

Author(s):

D. Gauthier ◽

L. Desjardins ◽

J. A. Robitaille ◽

Y. Vigneault

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Wild Fish ◽

Atlantic Salmon Salmo Salar ◽

Natural Spawning ◽

Spawning Area ◽

Present Information

We present information on the reproduction of artificially reconditioned Atlantic salmon (Salmo salar) in an enclosed spawning area and report evidence that some of these fish are fit for natural spawning 1 yr after their previous reproduction as wild fish, in spite of numerous treatments and manipulations.

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Size selection from fishways and potential evolutionary responses in a threatened Atlantic salmon population

River Research and Applications ◽

10.1002/rra.3155 ◽

2017 ◽

Vol 33 (7) ◽

pp. 1004-1015 ◽

Cited By ~ 8

Author(s):

G. A. Maynard ◽

M. T. Kinnison ◽

J. D. Zydlewski

Keyword(s):

Atlantic Salmon ◽

Size Selection ◽

Salmon Population

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Advances in Fish Tagging and Marking Technology

Advances in Fish Tagging and Marking Technology ◽

10.47886/9781934874271.ch6 ◽

2012 ◽

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Release Time ◽

Tag Identification ◽

Penobscot River ◽

Salmon Population ◽

Declining Populations ◽

Simple Change ◽

Using Data ◽

Made In

<i>Abstract</i>.—Atlantic salmon <i>Salmo salar </i>smolts are stocked in the Penobscot River, Maine to supplement declining populations. Since 2000, approximately 550,000 hatchery smolts are annually released into the river, of which 32% of these (175,000) were marked with visual implant elastomer (VIE) tags indicating release time and location. Our study found that tag colors of adult returns were often misread due to confusion between green and yellow marks and between red and pink marks. Using data collected on mark readings in a controlled hatchery environment, we corrected for tag identification errors made in the field, thereby allowing adjustments to be made in the marked returns to accurately assess the number of returns from multiple stocking groups. When adult returns from multiple stocking groups were compared, significant differences were detected between stocking groups, including a three-fold difference between two of the stocking groups. Hence, a simple change in smolt stocking locations and times may be of value in the recovery of the Penobscot River salmon population.

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Stable isotopes suggest the location of marine feeding grounds of South European Atlantic salmon in Greenland

ICES Journal of Marine Science ◽

10.1093/icesjms/fsz258 ◽

2020 ◽

Vol 77 (2) ◽

pp. 593-603 ◽

Cited By ~ 1

Author(s):

Ana Almodóvar ◽

Graciela G Nicola ◽

Daniel Ayllón ◽

Clive N Trueman ◽

Ian Davidson ◽

...

Keyword(s):

Atlantic Salmon ◽

Population Decline ◽

Migration Route ◽

North Atlantic Current ◽

Migration Routes ◽

Δ13c And Δ15n ◽

Δ13c Values ◽

The North ◽

Salmon Population ◽

And Migration

Abstract Historical data on the oceanic distribution and migration routes of southernmost Atlantic salmon Salmo salar populations from Europe are almost non-existent, as no rigorous tagging initiatives have been conducted. Here, we used stable isotope data (δ13C and δ15N) of historic scale collections to identify the potential marine feeding areas of the largest salmon population in the Iberian Peninsula. Data were compared with published datasets from Northern Ireland, Wales, south England, and northeast UK coast, which correspond to series between 15- and 33-year long within the time period from 1958 to 2009. Temporal covariation in sea surface temperature, primary productivity, and δ13C values suggests that feeding areas of Iberian salmon are located around Greenland, both in the Labrador and the Irminger seas. Furthermore, δ13C values of Atlantic salmon from Canadian rivers reported in the literature are similar to those found in individuals from Spanish rivers. Our results suggest that Iberian salmon follow a westerly migration route towards Greenland instead of following the easterly branch of the North Atlantic current into the Norwegian Sea. Characterization of feeding patterns and migration routes might help to understand the causes of ongoing population decline and establish targeted conservation programmes for threatened Iberian salmon.

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Low but significant genetic differentiation underlies biologically meaningful phenotypic divergence in a large Atlantic salmon population

Molecular Ecology ◽

10.1111/mec.13383 ◽

2015 ◽

Vol 24 (20) ◽

pp. 5158-5174 ◽

Cited By ~ 37

Author(s):

Tutku Aykanat ◽

Susan E. Johnston ◽

Panu Orell ◽

Eero Niemelä ◽

Jaakko Erkinaro ◽

...

Keyword(s):

Genetic Differentiation ◽

Atlantic Salmon ◽

Significant Genetic Differentiation ◽

Phenotypic Divergence ◽

Salmon Population

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Variable migration and delay in two stock components of an Atlantic salmon population

Environmental Biology of Fishes ◽

10.1007/s10641-015-0378-4 ◽

2015 ◽

Vol 98 (6) ◽

pp. 1513-1523 ◽

Cited By ~ 3

Author(s):

K. Ó. Kristinsson ◽

G. Gudbergsson ◽

G. M. Gislason

Keyword(s):

Atlantic Salmon ◽

Salmon Population

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Temporally stable genetic structure and low migration in an Atlantic salmon population complex: implications for conservation and management

Evolutionary Applications ◽

10.1111/j.1752-4571.2007.00007.x ◽

2008 ◽

Vol 1 (1) ◽

pp. 137-154 ◽

Cited By ~ 56

Author(s):

Juha-Pekka Vähä ◽

Jaakko Erkinaro ◽

Eero Niemelä ◽

Craig R. Primmer

Keyword(s):

Genetic Structure ◽

Atlantic Salmon ◽

Salmon Population ◽

Conservation And Management

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Interannual changes in recruitment of the Atlantic salmon (Salmo salar) population in the River Oir (Lower Normandy, France): relationships with spawners and in-stream habitat

ICES Journal of Marine Science ◽

10.1016/j.icesjms.2005.02.008 ◽

2005 ◽

Vol 62 (4) ◽

pp. 695-707 ◽

Cited By ~ 22

Author(s):

Jean-Luc Baglinière ◽

Frédéric Marchand ◽

Vincent Vauclin

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Survival Rates ◽

Stream Habitat ◽

Juvenile Salmon ◽

Strongly Correlated ◽

Data Set ◽

Atlantic Salmon Salmo Salar ◽

Salmon Population ◽

The Mean

Abstract Since 1985, the dynamics of the Atlantic salmon (Salmo salar) population in the River Oir, a spawning tributary of the River Sélune (Lower Normandy, France), have been studied from a data set of parr density and the number and the age structure of migrating fish (smolts and adults). Parr densities (1.5–17.4 per 100 m2) and smolt production (0.25–9.2 per 100 m2) varied considerably from year to year. Migrating juveniles were mainly 1 year old. Abundance of parr and smolts was strongly correlated with 0+ densities. Egg-to-smolt survival rates were highly variable year on year (0.044–1.07%). During the juvenile freshwater phase, mortality was highest between the egg and the 0+ stage (97.5–99.9%). The fluctuations in abundance of juvenile salmon appear to be linked to the number and distribution of spawners within the stream during spawning, and also to the amount of silt deposition on the spawning beds. As a result, mortality was highest during the under-gravel phase, and the mean survival rate from egg to smolt was much lower than in rivers less impacted by human activities. Therefore, during the study period, the low production of smolts during some years might lead to a low renewal rate of the salmon population.

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