The Effect of Short-duration Seawater Exposure on the Swimming Performance of Wild and Hatchery-reared Juvenile Coho Salmon (Oncorhynchus kisutch) during Smoltification

1994 ◽  
Vol 51 (10) ◽  
pp. 2188-2194 ◽  
Author(s):  
C. J. Brauner ◽  
G. K. Iwama ◽  
D. J. Randall
Keyword(s):  
Fresh Water ◽  
Coho Salmon ◽  
Swimming Performance ◽  
Oncorhynchus Kisutch ◽  
Aerobic Metabolism ◽  
Wild Fish ◽  
Swimming Velocity ◽  
Hatchery Fish ◽  
Oxygen Carrying Capacity ◽  
Seawater Challenge

The critical swimming velocity (Ucrit) and haematology of wild and hatchery-reared coho salmon (Oncorhynchus kisutch) juveniles were examined in either fresh water or seawater following a 24-h seawater challenge, at the time of smoltification. In fresh water, wild smolts swam faster than hatchery-reared fish but this could largely be accounted for by scaling for body size. Transfer to seawater significantly elevated resting plasma [Na+] and reduced subsequent Ucrit in hatchery fish (by 12%) relative to that determined in fresh water but had no significant effect on resting plasma [Na+] and Ucrit in wild fish. Swimming the fish a second time in seawater after the initial 2-h exercise period resulted in a significant reduction in Ucrit relative to that in fresh water in both wild fish (16%) and hatchery fish (a further 14%); this relatively greater impairment in Ucrit in hatchery fish was due to a reduced hypo-osmoregulatory ability following seawater transfer that impairs conditions for muscle contractility and aerobic metabolism. Aerobic metabolism in seawater-exposed fish was affected in part through a reduction in haematocrit and an increase in plasma volume, reducing oxygen carrying capacity of the blood relative to conditions in fresh water.

Effect of Short-Duration Seawater Exposure on Plasma Ion Concentrations and Swimming Performance in Coho Salmon (Oncorhynchus kisutch) Parr

1992 ◽  
Vol 49 (11) ◽  
pp. 2399-2405 ◽  
Author(s):  
C. J. Brauner ◽  
J. M. Shrimpton ◽  
D. J. Randall
Keyword(s):  
Moisture Content ◽  
Coho Salmon ◽  
Swimming Performance ◽  
Oncorhynchus Kisutch ◽  
Strong Relationship ◽  
Swimming Velocity ◽  
Elevated Plasma ◽  
Ion Concentrations ◽  
Critical Swimming Velocity ◽  
Seawater Challenge

The effect of seawater (sw) on plasma ion concentrations and critical swimming velocity (Ucrit) was investigated in hatchery-reared coho salmon (Oncorhynchus kisutch) parr exposed to one of four treatments: 24 h of seawater exposure (SW1), 5–7 d of seawater (SW5), 24 h in seawater followed by 24 h in fresh water (SW-FW), and a freshwater control (FWC). Only the SW1 fish demonstrated a reduced Ucrit and, at rest, elevated plasma [Na+], [Cl−], and [SO42−]. With exercise, SW1 fish were characterized by an increase in plasma ion concentrations and a decrease in both hematocrit (Hct) and muscle moisture content. There is a strong relationship between plasma [Na+] at rest and Ucrit, where an optimal swimming velocity is obtained in animals with resting levels of approximately 147 mEq∙L−1. Traditionally, the 24-h seawater challenge is used to test the hypoosmoregulatory ability in smolting salmonids, however, our data suggest that it may also predict the aerobic swimming potential of salmonids following seawater transfer. We suggest that the reduction in Hct and increase in plasma [Na+] result in reduced oxygen delivery to the muscle and that decrease in muscle moisture content impairs the contractile process.

Effects of Early Rearing Environment on Stress Response, Immune Function, and Disease Resistance in Juvenile Coho (Oncorhynchus kisutch) and Chinook Salmon (O.tshawytscha)

1993 ◽  
Vol 50 (4) ◽  
pp. 759-766 ◽  
Author(s):  
Kira Salonius ◽  
George K. Iwama
Keyword(s):  
Disease Resistance ◽  
Chinook Salmon ◽  
Coho Salmon ◽  
Vibrio Anguillarum ◽  
Oncorhynchus Kisutch ◽  
Significant Rise ◽  
Wild Fish ◽  
Handling Stress ◽  
Hatchery Fish ◽  
Natural Water Body

Coho (Oncorhynchus kisutch) and chinook salmon (0. tshawytscha) from aquaculture and wild environments were subjected to handling (30–60 s of netting and aerial emersion) and disease challenges. Plasma cortisol concentrations ([cortisol]pl) in both coho and chinook salmon from wild environments were significantly elevated 4 h after handling. Colonized coho salmon (hatchery-reared fish, transported into a natural water body as fry) responded in a similar fashion to wild fish, while those reared entirely in the hatchery showed no significant rise in [cortisol]pl. The responses to handling stress were retained in wild and colonized coho salmon after 7 mo of hatchery rearing. A transient increase in the leukocyte to red blood cell ratio in both wild and hatchery-reared chinook salmon occurred 4 h after handling. Handling signficantly decreased the antibody-producing cell (APC) number in wild fish and elevated their [cortisol]plrelative to hatchery fish. Wild fish had the highest APC number among the three groups before the handling. No difference in resistance to Vibrio anguillarum was apparent in coho and chinook salmon among the different rearing environments, although chinook salmon were generally more susceptible; disease resistance was reduced in wild coho salmon after 7 mo of rearing in a hatchery.

scholarly journals Sex-specific differences in swimming, aerobic metabolism and recovery from exercise in adult coho salmon (Oncorhynchus kisutch) across ecologically relevant temperatures

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
K Kraskura ◽  
E A Hardison ◽  
A G Little ◽  
T Dressler ◽  
T S Prystay ◽  
...  
Keyword(s):  
Adult Female ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Swimming Performance ◽  
Oncorhynchus Kisutch ◽  
Mortality Rates ◽  
Aerobic Metabolism ◽  
Exhaustive Exercise ◽  
Aerobic Scope ◽  
Cost Of Transport

Abstract Adult female Pacific salmon can have higher migration mortality rates than males, particularly at warm temperatures. However, the mechanisms underlying this phenomenon remain a mystery. Given the importance of swimming energetics on fitness, we measured critical swim speed, swimming metabolism, cost of transport, aerobic scope (absolute and factorial) and exercise recovery in adult female and male coho salmon (Oncorhynchus kisutch) held for 2 days at 3 environmentally relevant temperatures (9°C, 14°C, 18°C) in fresh water. Critical swimming performance (Ucrit) was equivalent between sexes and maximal at 14°C. Absolute aerobic scope was sex- and temperature-independent, whereas factorial aerobic scope decreased with increasing temperature in both sexes. The full cost of recovery from exhaustive exercise (excess post-exercise oxygen consumption) was higher in males compared to females. Immediately following exhaustive exercise (i.e. 1 h), recovery was impaired at 18°C for both sexes. At an intermediate time scale (i.e. 5 h), recovery in males was compromised at 14°C and 18°C compared to females. Overall, swimming, aerobic metabolism, and recovery energetics do not appear to explain the phenomenon of increased mortality rates in female coho salmon. However, our results suggest that warming temperatures compromise recovery following exhaustive exercise in both male and female salmon, which may delay migration progression and could contribute to en route mortality.

Changes in Cortisol Dynamics in Wild and Hatchery-Reared Juvenile Coho Salmon (Oncorhynchus kisutch) During Smoltification

1994 ◽  
Vol 51 (10) ◽  
pp. 2179-2187 ◽  
Author(s):  
J. Mark Shrimpton ◽  
Nicholas J. Bernier ◽  
David J. Randall
Keyword(s):  
Atpase Activity ◽  
Plasma Cortisol ◽  
Coho Salmon ◽  
Gradual Increase ◽  
Oncorhynchus Kisutch ◽  
Cortisol Concentration ◽  
Wild Fish ◽  
Hatchery Fish ◽  
Corticosteroid Receptor ◽  
Cr Concentration

Cortisol dynamics were examined in hatchery and wild juvenile coho salmon (Oncorhynchus kisutch) over the spring of 1991 and 1992 when the fish were smolting. Wild fish were caught in the upper Quinsam River, British Columbia and at the downstream enumeration fence when they started to migrate. Two groups of hatchery fish were from the top and bottom ends of an earthen rearing channel. Plasma cortisol levels increased during the spring in all groups, but were significantly greater in wild than in hatchery smolts. The half-life of plasma cortisol decreased as fish smolted; however, there was no difference among the groups. Corticosteroid receptor (CR) concentration and affinity decreased during the spring. Wild fish consistently possessed the greatest gill concentration of CR. The change in dissociation constant (kD) was similar for hatchery and wild fish during spring 1991. In 1992, hatchery fish showed a similar gradual increase. In contrast, wild fish did not show an increase in kD until May. The changes in cortisol concentration in the plasma and the CR kD occurred synchronously with the increase in Na+K+ATPase activity in wild fish, which showed the greatest increase in kD, plasma cortisol, and Na+K+ATPase activity.

scholarly journals Evidence for Freshwater Residualism in Coho Salmon, Oncorhynchus kisutch, From a Watershed on the North Coast of British Columbia

2017 ◽  
Vol 130 (4) ◽  
pp. 336 ◽  
Author(s):  
Eric A Parkinson ◽  
Chris J Perrin ◽  
Daniel Ramos-Espinoza ◽  
Eric B Taylor
Keyword(s):  
British Columbia ◽  
Fresh Water ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Oncorhynchus Kisutch ◽  
Water Levels ◽  
North Coast ◽  
The North ◽  
Seaward Migration ◽  
Mature Fish

The Coho Salmon, Oncorhynchus kisutch, is one of seven species of Pacific salmon and trout native to northeastern Pacific Ocean watersheds. The species is typically anadromous; adults reproduce in fresh water where juveniles reside for 1–2 years before seaward migration after which the majority of growth occurs in the ocean before maturation at 2–4 years old when adults return to fresh water to spawn. Here, we report maturation of Coho Salmon in two freshwater lakes on the north coast of British Columbia apparently without their being to sea. A total of 15 mature fish (11 males and four females) were collected in two lakes across two years. The mature fish were all at least 29 cm in total length and ranged in age from three to five years old. The occurrence of Coho Salmon that have matured in fresh water without first going to sea is exceedingly rare in their natural range, especially for females. Such mature Coho Salmon may represent residual and distinct breeding populations from those in adjacent streams. Alternatively, they may result from the ephemeral restriction in the opportunity to migrate seaward owing to low water levels in the spring when Coho Salmon typically migrate to sea after 1–2 years in fresh water. Regardless of their origin, the ability to mature in fresh water without seaward migration may represent important adaptive life history plasticity in response to variable environments.

Osmoregulatory Ability of Wild Coho Salmon (Oncorhynchus kisutch) and Dolly Varden Char (Salvelinus malma) Smolts

1988 ◽  
Vol 45 (8) ◽  
pp. 1487-1490 ◽  
Author(s):  
Scott W. Johnson ◽  
Jonathan Heifetz
Keyword(s):  
Water Temperature ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Dolly Varden ◽  
Salvelinus Malma ◽  
Small Stream ◽  
Fish Size ◽  
Dolly Varden Char ◽  
Seawater Challenge ◽  
Osmoregulatory Ability

Osmoregulatory ability of wild coho salmon (Oncorhynchus kisutch) and Dolly Varden char (Salvelinus malma) smolts migrating from a small stream in southeastern Alaska was assessed by plasma Na+ levels after a 24-h seawater challenge. Osmoregulatory ability of coho salmon was unaffected by time of out-migration, water temperature, and fish size. Osmoregulatory ability of Dolly Varden char was apparently affected by time of out-migration or water temperature but not by fish size. Char migrating in the first half of the migration period, when water temperature was usually < 8.0 °C, had lower plasma Na+ levels than did char migrating in the second half when temperatures were [Formula: see text]. A plasma Na+ threshold of 170 mmol∙L−1, used by others to separate smolts from silvery parr, indicated that 70% of the coho salmon and 80% of the Dolly Varden char we sampled were physiologically prepared to enter seawater. The remaining fish may have suffered some level of osmoregulatory stress.

Differences in Measurements of Smolt Development Between Wild and Hatchery-Reared Juvenile Coho Salmon (Oncorhynchus kisutch) Before and After Saltwater Exposure

1994 ◽  
Vol 51 (10) ◽  
pp. 2170-2178 ◽  
Author(s):  
J. Mark Shrimpton ◽  
Nicholas J. Bernier ◽  
George K. Iwama ◽  
David J. Randall
Keyword(s):  
Citrate Synthase ◽  
Coho Salmon ◽  
Sea Water ◽  
Salt Water ◽  
Oncorhynchus Kisutch ◽  
Sodium Concentration ◽  
Chloride Cells ◽  
Plasma Sodium ◽  
Hatchery Fish ◽  
Saltwater Tolerance

We compared the saltwater tolerance of coho salmon (Oncorhynchus kisutch) juveniles that were reared in different environments. The groups examined consisted of fish reared exclusively in the hatchery, a hatchery group transplanted into the upper watershed of the river (colonized), and wild fish from natural spawning broodstock in the river. Although hatchery fish were much larger than their wild or colonized counterparts, they consistently showed a reduced saltwater tolerance as assessed by a much greater perturbation in plasma sodium concentration following transfer to salt water. Within each group there was no relationship between size of the fish and saltwater tolerance. Following transfer to sea water, hatchery fish showed a significant decline in haematocrit and a significant increase in circulating plasma cortisol concentration. Neither of these changes was seen in wild smolts. Hatchery fish possessed fewer chloride cells, and lower specific activities of the enzymes Na+K+ATPase and citrate synthase. The weaker osmoregulatory ability of hatchery fish led to a greater mortality following abrupt transfer to 35‰ seawater. We believe that the differences in saltwater tolerance seen among the different groups of fish are due to rearing environment.

scholarly journals Hypophysectomy of coho salmon (Oncorhynchus kisutch) and survival in fresh water and seawater

Aquaculture ◽  
1987 ◽  
Vol 65 (3-4) ◽  
pp. 343-352 ◽  
Author(s):  
Richard S. Nishioka ◽  
N.Harold Richman ◽  
Graham Young ◽  
Patrick Prunet ◽  
Howard A. Bern
Keyword(s):  
Fresh Water ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch

Density-Dependence at Sea for Coho Salmon (Oncorhynchus kisutch)

1990 ◽  
Vol 47 (9) ◽  
pp. 1765-1772 ◽  
Author(s):  
J. M. Emlen ◽  
R. R. Reisenbichler ◽  
A. M. McGie ◽  
T. E. Nickelson
Keyword(s):  
Density Dependence ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Density Dependent ◽  
Density Dependent Mortality ◽  
Hatchery Fish ◽  
Statistical Assumptions ◽  
Diminishing Returns ◽  
Salmon Hatchery ◽  
Dependent Mortality

The success of expanded salmon hatchery programs will depend strongly on the degree of density-induced diminishing returns per smolt released. Several authors have addressed the question of density-dependent mortality at sea in coho salmon (Oncorhynchus kisutch), but have come to conflicting conclusions. We believe there are compelling reasons to reinvestigate the data, and have done so for public hatchery fish, using a variety of approaches. The results provide evidence that survival of these public hatchery fish is negatively affected, directly by the number of public hatchery smolts and indirectly by the number of private hatchery smolts. These results are weak, statistically, and should be considered primarily as a caution to those who, on the basis of other published work, believe that density-dependence does not exist. The results reported here also re-emphasize the often overlooked point that inferences drawn from data are strongly biased by investigators' views of how the systems of interest work and by the statistical assumptions they make preparatory to the analysis of those data.

Potential benefits of a conservation hatchery program for supplementing Oregon coast coho salmon (Oncorhynchus kisutch) populations: a stochastic model investigation

2005 ◽  
Vol 62 (8) ◽  
pp. 1920-1935 ◽  
Author(s):  
Gretchen R Oosterhout ◽  
Charles W Huntington ◽  
Thomas E Nickelson ◽  
Peter W Lawson
Keyword(s):  
Habitat Restoration ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Solution Space ◽  
Oregon Coast ◽  
Hatchery Fish ◽  
Natural Production ◽  
Management Actions ◽  
Genetic Risks ◽  
Hatchery Program

This study developed a stochastic life cycle model to simulate idealized supplementation strategies to investigate the following question: under what circumstances could hatchery fish stocking contribute to the recovery of Oregon coast coho salmon (Oncorhynchus kisutch)? Simulations were used to find a solution space, defined by the attributes of wild and hatchery-bred salmon, their offspring, and their environments, where hatchery fish could supplement natural production without further depressing it until natural or human factors restricting production were relieved. These simulations suggest that short-duration, tightly controlled, low-intensity conservation hatchery programs designed to minimize genetic and ecological risks may yield minor short-term increases in adult coho salmon abundance while posing significant ecological and genetic risks. No solution space was found that indicated clear long-term benefits from such a supplementation program. Of all the management actions modeled, habitat restoration offered by far the largest and only permanent gains in coho salmon abundance while posing no genetic or ecological risk to the fish. The modeled benefits of habitat restoration were significant regardless of assumptions made about the fitness of hatchery fish and their offspring.

Sign in / Sign up

Export Citation Format

Share Document