Restocking Depleted Sockeye Salmon Areas by Transfer of Eggs

1946 ◽  
Vol 6e (7) ◽  
pp. 483-490 ◽  
Author(s):  
R. E. Foerster
Keyword(s):  
Sockeye Salmon ◽  
Fraser River ◽  
Commercial Fishery ◽  
Lake Region ◽  
Spawning Areas ◽  
Subsequent Identification

Eggs from Cultus lake, a lower Fraser river tributary, and from Adams river, in the Shuswap lake region, were transferred to Eagle river, a formerly important sockeye salmon stream at the head of Shuswap lake. The resulting fingerlings were marked, prior to liberation into Eagle river, by removal of certain fins for subsequent identification. Recovery of surviving adults—few in the commercial fishery, few, if any, in the original native spawning areas, none at Eagle river from the Cultus lake egg transfers and very few from the Adams river shipments—indicates that restoration of depleted sockeye areas cannot be achieved merely by introducing eggs from any outside well-populated areas.

scholarly journals Physiology of individual late-run Fraser River sockeye salmon (Oncorhynchus nerka) sampled in the ocean correlates with fate during spawning migration

2006 ◽  
Vol 63 (7) ◽  
pp. 1469-1480 ◽  
Author(s):  
Steven J Cooke ◽  
Scott G Hinch ◽  
Glenn T Crossin ◽  
David A Patterson ◽  
Karl K English ◽  
...  
Keyword(s):  
Sockeye Salmon ◽  
Acute Stress ◽  
Oncorhynchus Nerka ◽  
Spawning Migration ◽  
Fraser River ◽  
Stress Indicators ◽  
Spawning Areas ◽  
Plasma Estradiol ◽  
Somatic Energy ◽  
Estradiol Levels

Beginning in 1995, segments of the late-run sockeye salmon (Oncorhynchus nerka) stocks from the Fraser River, British Columbia, have initiated upriver spawning migration up to 6 weeks earlier than historical records; and those fish have experienced high rates of en route mortality. We examined the correlations between physiological and energetic status prior to river entry with subsequent migratory performance of individual salmon using telemetry and noninvasive biopsies for Adams–Thompson–Shuswap (Adams) and Weaver–Harrison (W–H) stocks. Salmon that failed to reach the river were characterized by a tendency to have elevated levels of chronic and acute stress indicators. For one stock of fish (i.e., Adams) that entered the river, those that died before reaching spawning grounds were individuals with low gross somatic energy. Furthermore, females tended to have elevated plasma estradiol levels. When contrasting fish with different behaviours and fates, fish that did not hold in the estuary and subsequently died tended to have less energy than fish that held and reached spawning areas. Females from the former group also had higher 11-ketotestosterone and estradiol levels relative to those from the later group. These data suggest that differences in physiological and energetic status may be associated with high en route mortality in late-run sockeye salmon.

Skeena River Sockeye Escapement and Distribution

1952 ◽  
Vol 8c (7) ◽  
pp. 453-468 ◽  
Author(s):  
J. R. Brett
Keyword(s):  
Sockeye Salmon ◽  
River System ◽  
The Other ◽  
Population Estimates ◽  
Commercial Fishery ◽  
Actual Number ◽  
Spawning Areas ◽  
Skeena River ◽  
Best Estimates ◽  
Spawning Streams

Population estimates made from observations on the number of sockeye salmon in the various spawning streams of the Skeena River, B.C., during the period 1944–48 are presented. The methods used include a fence count at Babine Lake, the most important spawing area, supplemented by stream counting in the other areas and sample tagging at Lakelse. Estimates made at Babine by the latter methods were compared with the fence counts; the stream count estimates were about one-third of the actual number present, whereas estimates from tagging were about twice the actual.A brief description of the spawning streams of the Skeena is accompanied by a map showing their location. Best estimates of 1946–47 escapements to major spawning areas are: Babine, 480,000; Morice, 70,000; Bear, 42,000; Lakelse, 29,000. These comprise 92 per cent of the total for the river system. The area of the spawning beds used by sockeye in the system is about 100 acres, or of the order of 1.5 square yards per spawning pair. The division of the whole run is approximately 45 per cent to the commercial fishery, 6 per cent to the Indian fishery, and 49 per cent escapement.

Evaluation of the Depensatory Fishing Hypothesis as an Explanation for Population Cycles in Fraser River Sockeye Salmon (Oncorhynchus nerka)

1994 ◽  
Vol 51 (8) ◽  
pp. 1839-1854 ◽  
Author(s):  
A. J. Cass ◽  
C. C. Wood
Keyword(s):  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Population Cycles ◽  
Convincing Evidence ◽  
Fraser River ◽  
Commercial Fishery ◽  
Cyclic Behaviour ◽  
Considerable Debate ◽  
Recent Trends ◽  
Mixed Stock

Causes of cyclic fluctuations in the abundance of Fraser River sockeye (Oncorhynchus nerka) have been the focus of considerable debate for much of this century. Most hypotheses to explain cyclic behaviour in Fraser River sockeye centre on identifying agents of depensatory mortality, and several recent papers argue that sockeye cycles are maintained primarily by depensatory fishing patterns. We assess the evidence for depensatory fishing as an explanation for these cycles. Using simulations, we demonstrate that empirical evidence for depensatory fishing is likely an artifact caused by bias in estimating stock composition of catches in mixed-stock fisheries. Moreover, recent trends in harvest rates among comigrating stocks with asynchronous cycles are inconsistent with the depensatory fishing hypothesis. It also seems very unlikely that aboriginal and early commercial fisheries were intensive enough to maintain cycles that persisted prior to 1860. Only during the unregulated, early commercial fishery prior to the collapse of the upriver runs following the 1913–14 disaster at Hell's Gate is there any convincing evidence of depensatory fishing.

Biochemical Studies on Sockeye Salmon During Spawning Migration: XI. The Free Histidine Content of the Tissues

1960 ◽  
Vol 17 (3) ◽  
pp. 347-351 ◽  
Author(s):  
J. D. Wood ◽  
D. W. Duncan ◽  
M. Jackson
Keyword(s):  
Amino Acid ◽  
Sockeye Salmon ◽  
Alimentary Tract ◽  
Oncorhynchus Nerka ◽  
The Other ◽  
Spawning Migration ◽  
Fraser River ◽  
Initial Value ◽  
Spawning Grounds ◽  
Biochemical Studies

During the first 250 miles (400 km) of spawning migration of Fraser River sockeye salmon (Oncorhynchus nerka) the free histidine content of the muscle, alimentary tract, and head+skin+bones+tail decreased to a small fraction of the initial value. A further decrease occurred in the levels of this amino acid in the alimentary tract during the subsequent 415-mile (657-km) migration to the spawning grounds, no change being observed with the other tissues. Comparatively small changes in free histidine were found with heart, spleen, liver, kidney and gonads during migration.

A widespread decrease in productivity of sockeye salmon (Oncorhynchus nerka) populations in western North America

2012 ◽  
Vol 69 (8) ◽  
pp. 1255-1260 ◽  
Author(s):  
Randall M. Peterman ◽  
Brigitte Dorner
Keyword(s):  
Sockeye Salmon ◽  
Spatial Scales ◽  
Oncorhynchus Nerka ◽  
Geographic Area ◽  
Fraser River ◽  
Western North America ◽  
Southeast Alaska ◽  
The Past ◽  
Large Geographic Area ◽  
Marine Areas

We used data on 64 stocks of sockeye salmon ( Oncorhynchus nerka ) from British Columbia (B.C.), Washington, and Alaska to determine whether recent decreases in abundance and productivity observed for Fraser River, B.C., sockeye have occurred more widely. We found that decreasing time trends in productivity have occurred across a large geographic area ranging from Washington, B.C., southeast Alaska, and up through the Yakutat peninsula, Alaska, but not in central and western Alaska. Furthermore, a pattern of predominantly shared trends across southern stocks and opposite trends between them and stocks from western Alaska was present in the past (1950–1985), but correlations have intensified since then. The spatial extent of declining productivity of sockeye salmon has important implications for management as well as research into potential causes of the declines. Further research should focus on mechanisms that operate at large, multiregional spatial scales, and (or) in marine areas where numerous correlated sockeye stocks overlap.

The Influence of Climate on the Stock and Recruitment of Pink and Sockeye Salmon from the Fraser River, British Columbia, Canada

2004 ◽  
Vol 133 (6) ◽  
pp. 1396-1412 ◽  
Author(s):  
R. J. Beamish ◽  
J. T. Schnute ◽  
A. J. Cass ◽  
C. M. Neville ◽  
R. M. Sweeting
Keyword(s):  
British Columbia ◽  
Sockeye Salmon ◽  
Fraser River ◽  
Stock And Recruitment

Recent Colonization of a Major Salmon-Producing Lake in British Columbia by Pacific Lamprey (Lampetra tridentata)

1984 ◽  
Vol 41 (2) ◽  
pp. 278-285 ◽  
Author(s):  
Susan P. Farlinger ◽  
Richard J. Beamish
Keyword(s):  
British Columbia ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Nursery Area ◽  
Commercial Fishery ◽  
Rock Slide ◽  
Pacific Lamprey ◽  
Natural Lake ◽  
Lampetra Tridentata

Pacific lamprey (Lampetra tridentata) were first observed in Babine Lake, the largest natural lake wholly contained in British Columbia, in 1963 and are currently found along approximately 15% of the length of the lake near the outlet. The number of spawning adults in 1982 was estimated to be 7281. Since Babine Lake is a major nursery area for sockeye salmon (Oncorhynchus nerka), the colonization of this lake by a parasitic lamprey is of concern, particularly if the species can become nonanadromous. The colonization may be beneficial if a commercial fishery can be sustained and if the species does not begin to feed in freshwater. The reason for the recent colonization is unknown but it coincides with increased human manipulation of fishes and habitat, including the removal of a major rock slide, 65 km downstream of the lake.

Intact genetic structure and high levels of genetic diversity in bottlenecked sockeye salmon (Oncorhynchus nerka) populations of the Fraser River, British Columbia, Canada

2000 ◽  
Vol 57 (10) ◽  
pp. 1985-1998 ◽  
Author(s):  
Ruth E Withler ◽  
Khai D Le ◽  
R John Nelson ◽  
Kristina M Miller ◽  
Terry D Beacham
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Genetic Structure ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Allelic Diversity ◽  
Lower Proportion ◽  
Fraser River ◽  
Rare Alleles ◽  
Genetic Bottlenecks

Analysis of six microsatellite loci in 5800 sockeye salmon (Oncorhynchus nerka) from 29 Fraser River populations provided little evidence of genetic bottlenecks or mass straying in upper Fraser sockeye salmon resulting from reduced abundances following 1913-1914 rockslides in the Fraser canyon and successive decades of high exploitation. Upper Fraser populations were not characterized by a paucity of rare alleles, a sensitive indicator of populations in which effective size has been recently reduced. Heterozygosity and allelic diversity did not differ consistently between lower and upper Fraser populations. Throughout the watershed, early-migrating populations had lower allelic diversity and a lower proportion of rare alleles than did late-migrating ones. Genetic differentiation between upper and lower Fraser populations and heterogeneity among lower Fraser populations supported the suggestion that Fraser sockeye salmon are descendants of at least two postglacial "races." Variation among lakes within regions was the strongest component of genetic structure, accounting for five times the variation among populations within lakes and more than two times the variation among regions. Extensive historical transplants of eggs and juveniles apparently resulted in lit tle gene flow among regions, but three populations were reestablished or rebuilt as the result of more recent transplants.

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