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.

Temperature Selection of Juvenile Atlantic Salmon (Salmo salar) as Influenced by Various Toxic Substances

1976 ◽  
Vol 33 (8) ◽  
pp. 1722-1730 ◽  
Author(s):  
R. H. Peterson
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Toxic Substances ◽  
Term Survival ◽  
Preferred Temperature ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Sodium Pentachlorophenate ◽  
Selection Of ◽  
Short Term Survival

Previous exposure to sodium pentachlorophenate (NaPCP), Guthion®, malathion, Dursban®, and Dibrom® lowered the preferred temperature for juvenile Atlantic salmon (Salmo salar) tested in a horizontal temperature gradient. Lindane, CuSO4, ZnSO4, CdSO4, Sevin®, heptachlor, and fenitrothion did not change the preferred temperature significantly. Comparison with other published results indicates that those substances that increase the preferred temperature are more toxic (based on relevant changes in 24-h LC50) at low temperatures and vice versa. It is suggested that such shifts in selected temperature may be of potential immediate, short-term, survival value to the fish.

Context-dependent responses of juvenile Atlantic salmon (Salmo salar) to forestry activities at multiple spatial scales within a river basin

2007 ◽  
Vol 64 (8) ◽  
pp. 1069-1079 ◽  
Author(s):  
Julie Deschênes ◽  
Marco A Rodríguez ◽  
Pierre Bérubé
Keyword(s):  
Atlantic Salmon ◽  
River Basin ◽  
Salmo Salar ◽  
Spatial Scales ◽  
Environmental Features ◽  
Multiple Spatial Scales ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Logging Effects ◽  
Study Sites

We used classification trees and regression trees to relate the incidence and density of juvenile Atlantic salmon (Salmo salar) to forestry activities measured at four spatial scales (subbasin and 8, 2, and 0.5 km radii upstream of study sites) and environmental features in 120 stream reaches of the Cascapedia River basin, Québec, Canada. At all scales, incidence increased with reach size and accessibility to the reach from the river mainstem. Incidence declined with areal coverage of logging at all scales, but only in larger reaches. The time horizon over which logging effects were detected increased with spatial scale. At all scales, density in salmon-bearing reaches increased with accessibility. Density in more accessible reaches was negatively related to logging over the preceding 9 years at the subbasin and 8 km scales, but no effects of logging on density were detected at the 2 and 0.5 km scales. Overall, apparent effects of logging activities on salmon incidence and density were mostly negative and strong, but were both markedly scale-dependent and conditional on environmental context.

Growth, biomass, and production of juvenile Atlantic salmon (Salmo salar L.) in two Miramichi River, New Brunswick, tributary streams

1982 ◽  
Vol 60 (7) ◽  
pp. 1647-1659 ◽  
Author(s):  
R. G. Randall ◽  
U. Paim
Keyword(s):  
Atlantic Salmon ◽  
New Brunswick ◽  
Salmo Salar ◽  
Growing Season ◽  
Early Summer ◽  
Initial Population ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Study Sites ◽  
June July

The production rate of juvenile Atlantic salmon (Salmo salar) was estimated at four sites in two tributary streams of the Miramichi River, New Brunswick, during the period September 1976 to October 1978. Annual production ranged between 0.27 and 5.12 g∙m−2∙year−1. Growth was largely restricted to a 4-month period in early summer. Among the four sites, age 0+ salmon attained a mean weight of between 0.95 and 3.50 g by the end of their first growing season (September) and densities in July ranged between 0.3 and 3.1 fry∙m−2∙Age 1+ parr grew to mean weights between 4.95 and 12.45 g by September, and June–July densities ranged between 0.03 and 0.6 parr∙m−2. Marking information indicated that most parr remained in the study sites from July to September, but larger proportions of migrant parr were recorded in October. Production during summer was directly and positively related to initial population densities. Production rates at these sites were lower than most other recorded values for juvenile Atlantic salmon. Biomass of salmon may have been below the carrying capacity of the environment at all four sites.

Effects of temperature, photoperiod, and season on the photobehaviour of juvenile Atlantic salmon (Salmo salar)

1990 ◽  
Vol 68 (6) ◽  
pp. 1098-1103 ◽  
Author(s):  
D. M. Rimmer ◽  
U. Paim
Keyword(s):  
Atlantic Salmon ◽  
Water Temperature ◽  
Salmo Salar ◽  
Temperature Increase ◽  
Seasonal Difference ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Effects Of Temperature ◽  
Thermal Stimuli ◽  
Selection Of

The selection of illuminated or shaded areas by juvenile Atlantic salmon (Salmo salar) was examined in relation to temperature and photoperiod. Water temperature had a strong effect on the photoresponse of salmon. Salmon acclimated to 14 °C and a 16-h photophase in summer selected illuminated areas when tested at their acclimation conditions, but rapidly became strongly photonegative while temperature fell to 7 °C. When tested under acclimation conditions of 7 °C and a 16-h photophase during summer, salmon selected shade, but still became distinctly photopositive as temperature increased to 14 °C. Under acclimation conditions of 14 °C and an 8-h photophase during summer, salmon selected illuminated areas, becoming photonegative as temperature fell. Thus, acclimation to photoperiod alone did not exert a clear effect on the photoresponse of summer salmon. If acclimated to 7 °C and an 8-h photophase in winter, salmon selected shade under acclimation conditions and remained photonegative also after temperature increased. Anomalously, after acclimation to 7 °C and an 8-h photophase in summer, salmon were photopositive at 7 °C, but became photonegative and selected shade upon temperature increase, indicating an endogenous seasonal difference not only in their response to thermal stimuli, but also in their susceptibility to acclimation regimes.

scholarly journals Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar)

2015 ◽  
Vol 41 (4) ◽  
pp. 1029-1051 ◽  
Author(s):  
Kirsten O. Hannesson ◽  
Elisabeth Ytteborg ◽  
Harald Takle ◽  
Grethe Enersen ◽  
Grete Bæverfjord ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Vertebral Column ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Sulphated Glycosaminoglycans

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.

Sign in / Sign up

Export Citation Format

Share Document