Genetic Divergence of Anadromous and Nonanadromous Atlantic Salmon (Salmo salar) in the River Namsen, Norway

1989 ◽  
Vol 46 (3) ◽  
pp. 406-409 ◽  
Author(s):  
Jukka Vuorinen ◽  
Ole Kristian Berg
Keyword(s):  
Life History ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Genetic Divergence ◽  
Gene Diversity ◽  
Atlantic Salmon Salmo Salar ◽  
Large Numbers ◽  
Salmon Fry ◽  
Strong Founder Effect ◽  
Electrophoretic Data

Anadromous and nonanadromous Atlantic salmon, Salmo salar, coexist in the River Namsen in Norway. We studied genetic divergence between these two life history types by using electrophoretic data from 38 protein loci. Although allele frequencies differed significantly between the types at four loci no fixed allele frequency difference was observed. Nei's genetic distance between the life history types, however, was 0.01 a relatively high value for Atlantic salmon populations. The genetic differences observed between anadromous and nonanadromous salmon accounted for 18.3% of the total gene diversity. The five nonanadromous salmon samples formed two genetically different groups corresponding to the upper and lower ranges of the nonanadromous salmon in the river. The average observed heterozygosity was 3.1% for anadromous and 1.0% for nonanadromous salmon. The low heterozygosity in nonanadromous salmon probably reflects a strong founder effect. Stockings of large numbers of anadromous salmon fry to the upper reaches of the River Namsen have caused no detectable hybridization with nonanadromous salmon. Also downstream migrating nonanadromous salmon have apparently not made any important genetic contribution to the anadromous fish.

Effect of time of day, time of year, and life history strategy on time budgeting in juvenile Atlantic salmon, Salmo salar

1999 ◽  
Vol 56 (12) ◽  
pp. 2397-2403 ◽  
Author(s):  
Sveinn K Valdimarsson ◽  
Neil B Metcalfe
Keyword(s):  
Life History ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Life History Strategy ◽  
Time Of Day ◽  
Life History Strategies ◽  
Foraging Efficiency ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Time Of Year

Traditionally, behavioural studies on juvenile Atlantic salmon, Salmo salar, have been conducted during the day in summer. It is known that Atlantic salmon become nocturnal in winter, but very little is known about their behaviour at that time. Therefore, observations in a seminatural stream were carried out during the day and night, from February to June, comparing diel and seasonal differences in behaviour between fish adopting alternative life history strategies. The results showed a general trend for more activity in spring than in winter, and the fish were found to be foraging at surprisingly low light levels. There were differences in relative feeding rate between the life history strategies; the early migrant fish foraged mostly during the day whereas the delayed migrant fish did more foraging at night. There is some evidence that the early migrant fish made fewer feeding attempts over the winter, which is surprising, since they grow faster over that period. This suggests differences in foraging efficiency, which could contribute to the separation into these two life history strategies.

A review of the need and possible uses for genetically standardized Atlantic salmon (Salmo salar) in research

2009 ◽  
Vol 43 (2) ◽  
pp. 121-126 ◽  
Author(s):  
U Grimholt ◽  
R Johansen ◽  
A J Smith
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Scientific Community ◽  
Basic Research ◽  
Fish Farming ◽  
Genetic Constitution ◽  
Atlantic Salmon Salmo Salar ◽  
Large Numbers ◽  
Pros And Cons ◽  
Farming Industry

Large numbers of Atlantic salmon ( Salmo salar) are used as research animals in basic research and to solve challenges related to the fish-farming industry. Most of this research is performed on farmed animals provided by local breeders or national breeding companies. The genetic constitution of these animals is usually unknown and highly variable. As a result, large numbers of fish are often needed to produce significant results, and results from one study are often impossible to reproduce in another facility. The production of standardized salmon could in many cases reduce the number of animals used in research and at the same time provide more reproducible results. This paper provides an overview of the methods available for the production of standardized Atlantic salmon, and discusses the pros and cons of each technique. The use of zebrafish and other well-defined laboratory fish species as a model for salmon is also discussed. Access to genetically defined fish would greatly benefit the scientific community, in the same way as genetically defined lines of rodents have revolutionized mammalian research.

Annual variation in size-selective mortality of Atlantic salmon (Salmo salar) fry

2001 ◽  
Vol 58 (6) ◽  
pp. 1187-1195 ◽  
Author(s):  
S P Good ◽  
J J Dodson ◽  
M G Meekan ◽  
D AJ Ryan
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Total Mortality ◽  
Weather Conditions ◽  
Fish Length ◽  
Selective Mortality ◽  
Atlantic Salmon Salmo Salar ◽  
Salmon Fry ◽  
Mean Size ◽  
The Mean

We investigated the size-selective mortality of Atlantic salmon (Salmo salar) fry during two consecutive summers that differed markedly in weather conditions. We sampled fry shortly after emergence in June and at the end of August to compare the distributions of back-calculated body size at hatching by examining otolith microstructure. Size-selective mortality was observed in both summers; however, the direction and strength of mortality differed. During the drought conditions of 1995, selective mortality was relatively weak and directed towards the smaller fry in the population. During the flood conditions of 1996, selective mortality was relatively strong and directed towards the larger fry of the same population. Interannual variability in size-selective mortality contributed to significant differences in the mean size of fry at the end of their first summer of life. Size-selective mortality rates estimated from the shifts in fish length at hatching observed during the first summer of life were comparable with published estimates of total mortality of Atlantic salmon fry, indicating that early mortality may be largely size selective. Mortality associated with hydroclimatic events can select against either small or large fish and is a key determinant of mean size attained by the end of the first summer of life.

Importance of the Variation in Life History Parameters of Atlantic Salmon (Salmo salar)

1985 ◽  
Vol 42 (3) ◽  
pp. 615-618 ◽  
Author(s):  
Richard L. Saunders ◽  
Charles B. Schom
Keyword(s):  
Life History ◽  
Atlantic Salmon ◽  
Population Size ◽  
Salmo Salar ◽  
Great Variability ◽  
Mature Male ◽  
Life History Parameters ◽  
Atlantic Salmon Salmo Salar ◽  
Sexually Mature ◽  
Mature Male Parr

Atlantic salmon (Salmo salar) demonstrate great variability in their life history; individuals from a given year-class can spawn during several years and can, therefore, breed with salmon from other year-classes. Atlantic salmon can mature after 1–4 sea-winters and some males mature as parr, during the second through fifth years, before going to sea. Salmon may survive to spawn more than once; some spawn several times. This variability in life history may be a safeguard against loss of small stocks through several successive years of reproductive failure, since nonspawning individuals in the river or at sea could spawn in subsequent years. Spawning populations are frequently quite small. The effective spawning population size may be potentially much larger, however, since members of several year-classes, including sexually mature male parr and anadromous adults of various ages, contribute to spawning. The level of inbreeding may be relatively low, since a number of year-classes, each with different sets of parents, are represented during spawning.

Genetically distinct sympatric populations of resident and anadromous Atlantic salmon, Salmo salar

1989 ◽  
Vol 67 (6) ◽  
pp. 1453-1461 ◽  
Author(s):  
E. Verspoor ◽  
L. J. Cole
Keyword(s):  
Life History ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
River System ◽  
Population Variation ◽  
The Other ◽  
Gene Pools ◽  
Sympatric Populations ◽  
Polymorphic Loci ◽  
Atlantic Salmon Salmo Salar

Atlantic salmon (Salmo salar) from Little Gull Lake on the Gander River system of central Newfoundland were found to be electrophoretically polymorphic at 5 of 20 protein loci screened. Four of the polymorphic loci were structural and one was regulatory. Major heterozygote deficiencies relative to Castle–Hardy–Weinberg expectations were detected at the two most polymorphic loci, Aat-3 and Mdh-3,4, and significant nonrandom associations between genotypes at these loci and the other polymorphic loci, Sdh-1, Me-2, and Pgm1-t, were also found. The heterozygote deficiencies and the nonrandom genotype associations were attributable to the admixture of genetically distinct gene pools of resident and anadromous salmon in the lake. This is the first documented case of coexistence of reproductively separated populations of Atlantic salmon of the two life history types, and shows that the sympatric occurrence of the two forms can represent between-population variation.

Seasonal and Developmental Variation in the Lethality of Zinc to Juvenile Atlantic Salmon (Salmo salar)

1977 ◽  
Vol 34 (1) ◽  
pp. 139-141 ◽  
Author(s):  
V. Zitko ◽  
W. G. Carson
Keyword(s):  
Life History ◽  
Atlantic Salmon ◽  
Developmental Stage ◽  
Salmo Salar ◽  
Water Hardness ◽  
Developmental Variation ◽  
Atlantic Salmon Salmo Salar ◽  
Sensitive Stage ◽  
Juvenile Atlantic Salmon ◽  
Lethal Level

The incipient lethal level (ILL) of zinc to juvenile Atlantic salmon (Salmo salar) in fresh water at a water hardness of 14 mg/ℓ varies from 150 to 1000 μg/ℓ as a function of season and developmental stage of the fish. The ILL increases from 500 to 1000 μg/ℓ during the 1st yr and decreases to 150 μg/ℓ in the following spring. The more sensitive stage in the salmon's life history, evidenced by decrease of ILL coincides with and is probably related to initial stages of the parr–smolt transformation.

Selection of Microhabitat in Summer by Juvenile Atlantic Salmon (Salmo salar)

1987 ◽  
Vol 44 (1) ◽  
pp. 120-129 ◽  
Author(s):  
D. L. Morantz ◽  
R. K. Sweeney ◽  
C. S. Shirvell ◽  
D. A. Longard
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
The Body ◽  
Flow Conditions ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Salmon Fry ◽  
Study Sites ◽  
Selection Of ◽  
Atlantic Salmon Parr

This study was designed to define the microhabitats selected in summer by juvenile Atlantic salmon (Salmo salar). Curves were developed describing the preference of 880 young salmon for water velocity at the fish's position (nose velocity), mean water column velocity, total water depth, and stream substrate size. Study sites were chosen in six morphologically diverse streams in Nova Scotia and New Brunswick during 1982–84. Of the four variables measured, only nose velocity chosen by both fry and parr was not significantly different among years or rivers. Atlantic salmon fry (< 65 mm) most frequently selected nose velocities between 5 and 15 cm∙s−1, small parr (65–100 mm) between 5 and 25 cm∙s−1 and large parr (> 100 mm) between 5 and 35 cm∙s−1. Apparently, juvenile salmon utilized water depths and stream substrates which varied within tolerable limits according to their availability in conjunction with preferred water velocities. Significant differences in the body shape and size of the pectoral fin of Atlantic salmon parr in different rivers did not influence the selection of nose velocities within the range of flow conditions sampled.

Sign in / Sign up

Export Citation Format

Share Document