Large-Scale Escapes of Farmed Atlantic Salmon (Salmo salar) into Norwegian Rivers Threaten Natural Populations

1991 ◽  
Vol 48 (3) ◽  
pp. 426-428 ◽  
Author(s):  
D. Gausen ◽  
V. Moen
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Large Scale ◽  
Natural Populations ◽  
Genetic Introgression ◽  
Fish Farms ◽  
Farmed Salmon ◽  
Atlantic Salmon Salmo Salar ◽  
Farmed Atlantic Salmon ◽  
And Behavior

We present data on Atlantic salmon (Salmo salar) which show that escaped farmed salmon enter Norwegian rivers in great numbers. Escaped farmed salmon comprised a substantial proportion of the mature salmon present on the spawning grounds in autumn. A potential for large-scale genetic introgression thus exists. The sex ratios, length distributions, and times of ascent of wild and farmed salmon differed significantly, reflecting major variations in biology and behavior. High proportions of farmed salmon (> 20%) were found only in rivers having fish farms situated closer than 20 km from the outlet.

scholarly journals Monitoring the incidence of escaped farmed Atlantic salmon, Salmo salar L., in rivers and fisheries of the United Kingdom and Ireland: current progress and recommendations for future programmes

2006 ◽  
Vol 63 (7) ◽  
pp. 1201-1210 ◽  
Author(s):  
Alan M. Walker ◽  
Malcolm C.M. Beveridge ◽  
Walter Crozier ◽  
Niall Ó Maoiléidigh ◽  
Nigel Milner
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Best Practice ◽  
British Isles ◽  
Fish Farms ◽  
Farmed Salmon ◽  
Atlantic Salmon Salmo Salar ◽  
The United Kingdom ◽  
Farmed Atlantic Salmon ◽  
Farming Industry

Abstract An inevitable consequence of the development of the Atlantic salmon, Salmo salar L., farming industry in coastal waters of the British Isles has been the loss of farmed salmon to the wild, their occurrence in inshore waters and rivers, and their appearance in coastal and freshwater fisheries. Monitoring programmes have been developed throughout the British Isles, variously using scientific sampling, catch records from coastal or freshwater fisheries or both, and scientific sampling of catches from in-river traps. We compare the results of these monitoring programmes with regional production and the numbers of escapees reported from marine fish farms. We also consider the effectiveness of the programmes for assessing the prevalence of farmed salmon that escape from marine cages. Finally, we make recommendations for improvements to these programmes and for the development of best practice, including the scientific sampling of in-river spawning stocks through fishery-independent sources, identification of fish origin based on at least two methods, assessment of the degree of incorrect classification, and the timely and accurate reporting of all escapes.

scholarly journals Horizontal movements of simulated escaped farmed Atlantic salmon (Salmo salar) in a western Norwegian fjord

2010 ◽  
Vol 67 (6) ◽  
pp. 1206-1215 ◽  
Author(s):  
Ove T. Skilbrei ◽  
Jens Christian Holst ◽  
Lars Asplin ◽  
Stein Mortensen
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Release Site ◽  
Fishing Effort ◽  
Fish Farms ◽  
Large Area ◽  
Atlantic Salmon Salmo Salar ◽  
Norwegian Fjord ◽  
Time Of Year ◽  
Farmed Atlantic Salmon

Abstract Skilbrei, O. T., Holst, J. C., Asplin, L., and Mortensen, S. 2010. Horizontal movements of simulated escaped farmed Atlantic salmon (Salmo salar) in a western Norwegian fjord. – ICES Journal of Marine Science, 67: 1206–1215. The dispersal of simulated escaped farmed Atlantic salmon (Salmo salar) in Hardangerfjord in western Norway was studied by telemetry. Tagged fish were released from fish farms on five different dates in the course of 1 year. Irrespective of the time of year, the fish dispersed rapidly, with a mean displacement from the release site of 5–7 km after 1 d, and 9–12 km after 2 d. Individual rates of movement varied, but were much higher than the rate of displacement from the release site, as fish moved around in the fjord basin in all directions. As a result, the fish were spread over an area of more than 500 km2 after 1 week. The number of released fish recorded in the fjord gradually declined after each release from ∼40% remaining in the fjord after 3 weeks to few or none after 7 weeks. In all, 38% moved out of the fjord, and 36 and 2% were reported as captured inside and outside the fjord, respectively. Their rapid dispersal suggests that concentrating efforts to recapture escaped salmon in the proximity of an escape site will probably not be successful, at least from locations of this type. In fact, the recaptures demonstrate that it is both necessary and possible to expand the fishing effort to cover a large area and to sustain it for several weeks to attain high rates of recapture. The wide dispersal of escaped fish potentially acting as vectors within the fjord basin also has implications for the spread of disease and parasites.

Spawning of Escaped Farmed Atlantic Salmon (Salmo salar): Hybridization of Females with Brown Trout (Salmo trutta)

1993 ◽  
Vol 50 (9) ◽  
pp. 1986-1990 ◽  
Author(s):  
A. F. Youngson ◽  
J. H. Webb ◽  
C. E. Thompson ◽  
D. Knox
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Brown Trout ◽  
Salmo Trutta ◽  
F1 Hybrids ◽  
Fish Farms ◽  
Atlantic Salmon Salmo Salar ◽  
Brown Trout Salmo Trutta ◽  
The Difference ◽  
Farmed Atlantic Salmon

Atlantic salmon (Salmo salar) and F1 hybrids between Atlantic salmon and brown trout (Salmo trutta) were distinguished among juvenile salmonids sampled at emergence from rivers in western and northern Scotland. Hybrids were present in samples obtained from seven of the 16 rivers examined. Salmon fry and hybrid fry that were demonstrably the progeny of female salmon that had escaped from fish farms were identified by detecting the presence of maternal canthaxanthin, a synthetic flesh colorant, in the juveniles' pigment load. Canthaxanthin was detected in 101 (4%) of the 2350 salmon and eight (35%) of the 23 hybrids examined. The difference in the frequencies of salmon and hybrids carrying canthaxanthin was significant. Escaped female salmon hybridized with trout more frequently than did wild females.

Prevalence and recurrence of escaped farmed Atlantic salmon (Salmo salar) in eastern North American rivers

2008 ◽  
Vol 65 (12) ◽  
pp. 2807-2826 ◽  
Author(s):  
Matthew R.J. Morris ◽  
Dylan J. Fraser ◽  
Anthony J. Heggelin ◽  
Frederick G. Whoriskey ◽  
Jonathan W. Carr ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
North American ◽  
Temporal Trends ◽  
Wild Salmon ◽  
Farmed Salmon ◽  
Atlantic Salmon Salmo Salar ◽  
In The Wild ◽  
Farmed Atlantic Salmon ◽  
Comprehensive Compilation

Knowledge of the prevalence of escaped farmed fishes in the wild is an essential first step to assessing the risk resulting from interactions between farmed and wild fishes. This is especially important in eastern North America, where Atlantic salmon ( Salmo salar ) aquaculture occurs near wild Atlantic salmon rivers and where many wild salmon populations are severely depressed. Here, we review the literature on the incidence of escaped farmed salmon in eastern North American rivers, for which there has been no comprehensive compilation to date. Escaped farmed salmon have been found in 54 of 62 (87%) rivers investigated within a 300 km radius of the aquaculture industry since 1984, including 11 rivers that contain endangered salmon populations. Averaged among all investigations, the proportional representation of farmed salmon among adults entering the rivers from the sea was 9.2% (range 0% to 100%). Where data were sufficient to examine temporal trends, farmed salmon proportions varied considerably over time, suggesting that escape events are episodic in nature. We conclude that escaped farmed salmon are sufficiently prevalent in eastern North American rivers to pose a potentially serious risk to the persistence of wild salmon populations, especially in those rivers that are adjacent to existing aquaculture sites.

Flavour and off-flavour in wild and farmed atlantic salmon from locations around northern ireland

1995 ◽  
Vol 31 (11) ◽  
pp. 259-264 ◽  
Author(s):  
L. J. Farmer ◽  
J. M. McConnell ◽  
T. D. J. Hagan ◽  
D. B. Harper
Keyword(s):  
Northern Ireland ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Scientific Basis ◽  
Wild Salmon ◽  
Farmed Salmon ◽  
Atlantic Salmon Salmo Salar ◽  
Short Period ◽  
Profiling Techniques ◽  
Farmed Atlantic Salmon

Sensory profiling techniques were used to investigate the odour and flavour of Atlantic salmon (Salmo salar) from six sources in order to determine (i) whether there was any scientific basis for reports of off-flavours in salmon from certain sources and (ii) whether farmed and wild salmon differed in terms of flavour attributes. There were no consistent differences in odour or flavour between sea-caught wild salmon and farmed salmon. However, river-caught wild salmon showed enhanced ‘earthy’ flavour and odour; GC-odour assessment studies have indicated that 2-methylisoborneol and geosmin contribute to these attributes. For a short period, wild river salmon from one source also suffered from a manure-like off-flavour which has been shown to be due to the presence of skatole. The source of this compound remains uncertain.

A Method of Separating Offspring from Farmed and Wild Atlantic Salmon (Salmo salar) based on Different Ratios of Optical Isomers of Astaxanthin

1991 ◽  
Vol 48 (3) ◽  
pp. 429-433 ◽  
Author(s):  
Harald Lura ◽  
Harald Saegrov
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
High Performance ◽  
Optical Isomers ◽  
Farmed Salmon ◽  
Atlantic Salmon Salmo Salar ◽  
Farmed Atlantic Salmon ◽  
Spawning Success

A method of separating eggs and alevins from wild and farmed Atlantic salmon (Salmo salar) is described, using high-performance liquid chromatography (HPLC) to trace optical isomers of astaxanthin commonly occurring in the diet of both wild and farmed salmon. The proportions of isomers in eggs and alevins of farmed salmon, fed synthetic astaxanthin, differ highly from those of wild fish. The method can be used as a tool to determine the spawning success of escaped farmed female Atlantic salmon.

Absence of Nematodes in Farmed Atlantic Salmon (Salmo salar L.) in Norway

2003 ◽  
Vol 66 (1) ◽  
pp. 122-124 ◽  
Author(s):  
BJØRN TORE LUNESTAD
Keyword(s):  
Soft Tissue ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Farmed Salmon ◽  
Enzyme Solution ◽  
Atlantic Salmon Salmo Salar ◽  
Nematode Larvae ◽  
Farmed Atlantic Salmon

In the present study, a total of 1,180 samples of muscle or viscera from Norwegian-farmed salmon (Salmo salar L.) were examined for the presence of nematode larvae. The samples represented all salmon-producing counties in Norway. The method applied was based on the degradation of fish soft tissue in an acidified pepsin enzyme solution. None of the samples examined in this study contained nematodes.

Minimizing marine ingredients in diets of farmed Atlantic salmon (Salmo salar): effects on liver and head kidney lipid class and fatty acid composition

2020 ◽  
Vol 46 (6) ◽  
pp. 2331-2353
Author(s):  
Maryam Beheshti Foroutani ◽  
Christopher C. Parrish ◽  
Jeanette Wells ◽  
Richard G. Taylor ◽  
Matthew L. Rise
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Atlantic Salmon ◽  
Lipid Class ◽  
Acid Composition ◽  
Salmo Salar ◽  
Head Kidney ◽  
Atlantic Salmon Salmo Salar ◽  
Farmed Atlantic Salmon
Sign in / Sign up

Export Citation Format

Share Document