Influence of Sea Temperature upon the Numbers of Grilse and Multi-Sea-Winter Atlantic Salmon (Salmo salar) Caught in the Vicinity of the River Dee (Aberdeenshire)

1985 ◽  
Vol 42 (9) ◽  
pp. 1513-1521 ◽  
Author(s):  
J. H. A. Martin ◽  
K. A. Mitchell
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
The Arctic ◽  
Average Weight ◽  
Regression Equations ◽  
Catch Per Unit Effort ◽  
Data Set ◽  
Sea Temperature ◽  
Atlantic Salmon Salmo Salar ◽  
High Seas

The possible influence of sea temperature upon the age of return of Atlantic salmon (Salmo salar) was examined using the catch and weight data of grilse and multi-sea-winter (MSW) salmon of the Aberdeen Harbour Board caught either within or adjacent to the River Dee (Aberdeenshire). This data set, apart from a 10-yr period of commercial confidentiality, is very suitable because uniformity of effort allowed catch per unit effort to be calculated. Only in the last few years was external pressure (high seas fishing) applied to the system. Various temperature series were examined but the known loci of high seas fishing and the temperature ranges involved suggested that the most relevant series is from the subarctic. Increase in temperature is shown to be associated with larger numbers of fish returning as MSW salmon and fewer as grilse. The average weight of grilse increases with grilse catch numbers. Regression equations for grilse and MSW salmon catch numbers are produced for the period 1877–1972. There is a marked 4-yr periodicity in the grilse catch data. A hypothesis is proposed that the temperature of the subarctic influences the migratory pattern, that fish travel further north into the Arctic/subarctic only during those years when the minimum temperature remains above 2 °C.

“Riverscape” genetics: river characteristics influence the genetic structure and diversity of anadromous and freshwater Atlantic salmon (Salmo salar) populations in northwest Russia

2012 ◽  
Vol 69 (12) ◽  
pp. 1947-1958 ◽  
Author(s):  
Mikhail Yu. Ozerov ◽  
Alexey E. Veselov ◽  
Jaakko Lumme ◽  
Craig R. Primmer
Keyword(s):  
Genetic Diversity ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Carrying Capacity ◽  
Salmonid Fishes ◽  
Microsatellite Data ◽  
Data Set ◽  
Atlantic Salmon Salmo Salar ◽  
Genetic Diversity And Structure ◽  
Genetic Structure And Diversity

Combining population genetic and landscape ecology approaches provides an understanding of how environmental factors affect individual dispersal, population size, and structure. We first generated a set of predictions of the expected effect of “riverscape” characteristics on salmonid genetic diversity and divergence, based on the results of earlier research on this topic in salmonid fishes. We then tested these predictions in a data set consisting of the microsatellite data and riverscape characteristics of 39 Atlantic salmon ( Salmo salar ) populations from northwest Russia. The carrying capacity of the river was an important factor shaping the genetic diversity and differentiation of Atlantic salmon populations in the region: salmon in rivers with a larger carrying capacity tended to have higher genetic diversity and lower genetic differentiation. The importance of other riverscape characteristics often varied between anadromous and freshwater populations. Taken together, these associations demonstrate a high and complex level of river landscape influence on the genetic diversity and structure of Atlantic salmon populations and highlight the importance of spawning and nursery area maintenance for the conservation of salmonids.

Fyke Net Catches as Indices of the Abundance of Brook Trout, Salvelinus fontinalis, and Atlantic Salmon, Salmo salar

1984 ◽  
Vol 41 (2) ◽  
pp. 377-380 ◽  
Author(s):  
P. M. Ryan
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Relative Abundance ◽  
Brook Trout ◽  
Salvelinus Fontinalis ◽  
Catch Per Unit Effort ◽  
Small Lakes ◽  
Population Densities ◽  
Atlantic Salmon Salmo Salar ◽  
Fyke Nets

The catch per unit effort (CPUE) data of brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) in fyke nets set in two small lakes in central Newfoundland were compared with population densities estimated with Schnabel multiple mark–recapture experiments each spring and fall from 1978 to 1982. The catchability of brook trout did not differ significantly between lakes or seasons, and CPUE was an index of the relative abundance of trout within and between lakes. In contrast, the catchability of Atlantic salmon differed greatly between lakes and varied seasonally, being greater in the spring but less in the fall than the catchability of brook trout. Comparisons of relative salmon abundance between lakes or of the relative abundance of brook trout to Atlantic salmon within or between lakes require a correction for seasonal differences in the catchability of salmon.

scholarly journals 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

2005 ◽  
Vol 62 (4) ◽  
pp. 695-707 ◽  
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.

Different Adaptation Strategies of Atlantic Salmon (Salmo salar) Populations to Extreme Climates with Special Reference to some Cold Norwegian Rivers

1986 ◽  
Vol 43 (5) ◽  
pp. 980-984 ◽  
Author(s):  
Arne Johan Jensen ◽  
Bjørn Ove Johnsen
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Temperature Regime ◽  
Growth Rates ◽  
Temperature Limit ◽  
Fixed Temperature ◽  
Sea Temperature ◽  
Atlantic Salmon Salmo Salar ◽  
Lower Temperature Limit ◽  
Lower Temperature

Some of the salmon rivers on the western and northern coasts of Norway are very cold, and the sea temperature outside these rivers is almost always higher than that in the river. Growth rates of Atlantic salmon (Salmo salar) parr and smolt ages and sizes have been examined in three such cold rivers. We found indications that the lower temperature limit for growth of Atlantic salmon is not a fixed temperature, but varies from population to population according to the temperature regime of their environment. Smolts are small, with average sizes of 12–13 cm total length. Females dominated in number among the smolts, but the dominance was less pronounced than in most other rivers. Strategies used by Norwegian salmon in cold rivers are therefore different from those employed by salmon in the northern extremes of the salmon's range in Canada.

Predicting climate change effects on subarctic–Arctic populations of Atlantic salmon (Salmo salar)

2013 ◽  
Vol 70 (2) ◽  
pp. 159-168 ◽  
Author(s):  
Richard D. Hedger ◽  
Line E. Sundt-Hansen ◽  
Torbjørn Forseth ◽  
Ola Ugedal ◽  
Ola H. Diserud ◽  
...  
Keyword(s):  
Climate Change ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Climate Models ◽  
Global Climate Models ◽  
Future Climate ◽  
The Arctic ◽  
Future Climate Change ◽  
Northern Norway ◽  
Atlantic Salmon Salmo Salar

We predict an increase in parr recruitment and smolt production of Atlantic salmon (Salmo salar) populations along a climate gradient from the subarctic to the Arctic in western and northern Norway in response to future climate change. Firstly, we predicted local stream temperature and discharge from downscaled data obtained from Global Climate Models. Then, we developed a spatially explicit individual-based model (IBM) parameterized for the freshwater stage, with combinations of three different postsmolt survival probabilities reflecting different marine survival regimes. The IBM was run for three locations: southern Norway (∼59°N), western Norway (∼62°N), and northern Norway (∼70°N). Increased temperatures under the future climate regimes resulted in faster parr growth, earlier smolting, and elevated smolt production in the western and northern locations, in turn leading to increased egg deposition and elevated recruitment into parr. In the southern location, density-dependent mortality of parr resulting from low summer wetted-areas reduced predicted future smolt production in comparison to the other locations. It can be inferred, therefore, that climate change may have both positive and negative effects on anadromous fish abundance within the subarctic–Arctic according to geographical region.

Prediction of Angler Success in an Atlantic Salmon, Salmo salar, Fishery Two Fishing Seasons in Advance

1986 ◽  
Vol 43 (12) ◽  
pp. 2531-2534 ◽  
Author(s):  
Patrick M. Ryan
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Catch Per Unit Effort ◽  
Atlantic Salmon Salmo Salar ◽  
Unit Effort ◽  
Seaward Migration

The number of young Atlantic salmon, Salmo salar, in the spring in two lakes at the headwaters of the Gander River, Newfoundland, was positively correlated (r = 0.99) with the number of smolts in the subsequent seaward migration over a 5-yr period. Angler success (catch per unit effort) in the grilse fishery on the Gander River over a 7-yr period was positively correlated (r = 0.81) with the number of young in the lakes prior to the opening of the angling season of the previous year. Measures of the abundance of young salmon in freshwaters prior to the smolt run can be used to predict the size of the smolt run and allow for compensatory modifications to the adult fishery a year in advance of acticipated low adult returns.

Changes in Mean Weight, Sea-Age Composition, and Catch-per-Unit-Effort of Atlantic Salmon (Salmo salar) Angled in the Godbout River, Quebec, 1859–1983

1986 ◽  
Vol 43 (2) ◽  
pp. 281-287 ◽  
Author(s):  
Alex T. Bielak ◽  
Geoffrey Power
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Age Groups ◽  
Fishing Effort ◽  
Commercial Fisheries ◽  
Catch Per Unit Effort ◽  
Age Composition ◽  
Atlantic Salmon Salmo Salar ◽  
The Mean ◽  
Selective Effects

A weight-age classification, based on recent catches, was retroactively applied to angled Atlantic salmon (Salmo salar) catches recorded in the log of the Godbout salmon club between 1859 and 1983. Over this period, numbers of salmon caught have fluctuated with a periodicity of 20–30 yr but catches have been maintained. There has been a big increase in fishing effort, and the proportion of two-sea-year to previously spawned fish has increased. The mean weight of these age groups has declined 0.005–0.009 kg∙yr−1. These changes are attributed to the selective effects of commercial fisheries on the stock.

scholarly journals A microsatellite baseline for genetic stock identification of European Atlantic salmon (Salmo salar L.)

2017 ◽  
Vol 75 (2) ◽  
pp. 662-674 ◽  
Author(s):  
John Gilbey ◽  
Jamie Coughlan ◽  
Vidar Wennevik ◽  
Paulo Prodöhl ◽  
Jamie R Stevens ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Life Stage ◽  
Stock Identification ◽  
Genetic Stock ◽  
Data Set ◽  
Atlantic Salmon Salmo Salar ◽  
North East ◽  
The North ◽  
Russian River

Abstract Atlantic salmon (Salmo salar L.) populations from different river origins mix in the North Atlantic during the marine life stage. To facilitate marine stock identification, we developed a genetic baseline covering the European component of the species’ range excluding the Baltic Sea, from the Russian River Megra in the north-east, the Icelandic Ellidaar in the west, and the Spanish Ulla in the south, spanning 3737 km North to South and 2717 km East to West. The baseline encompasses data for 14 microsatellites for 26 822 individual fish from 13 countries, 282 rivers, and 467 sampling sites. A hierarchy of regional genetic assignment units was defined using a combination of distance-based and Bayesian clustering. At the top level, three assignment units were identified comprising northern, southern, and Icelandic regions. A second assignment level was also defined, comprising eighteen and twenty-nine regional units for accurate individual assignment and mixed stock estimates respectively. The baseline provides the most comprehensive geographical coverage for an Atlantic salmon genetic data-set, and a unique resource for the conservation and management of the species in Europe. It is freely available to researchers to facilitate identification of the natal origin of European salmon.

Sign in / Sign up

Export Citation Format

Share Document