Protandry in Pacific salmon

2000 ◽  
Vol 57 (6) ◽  
pp. 1252-1257 ◽  
Author(s):  
Yolanda Morbey
Keyword(s):  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Pink Salmon ◽  
Statistical Procedure ◽  
Timing Data ◽  
Mating Opportunities ◽  
Gender Specific ◽  
Specific Timing

Protandry, the earlier arrival of males to the spawning grounds than females, has been reported in several studies of Pacific salmon (Oncorhynchus spp.). However, the reasons for protandry in salmon are poorly understood and little is known about how protandry varies among and within populations. In this study, protandry was quantified in a total of 105 years using gender-specific timing data from seven populations (one for pink salmon (O. gorbuscha), three for coho salmon (O. kisutch), two for sockeye salmon (O. nerka), and one for chinook salmon (O. tshawytscha)). Using a novel statistical procedure, protandry was found to be significant in 90% of the years and in all populations. Protandry may be part of the males' strategy to maximize mating opportunities and may facilitate mate choice by females.

Effect of incubation temperature on the development of five species of Pacific salmon (Oncorhynchus) embryos and alevins

1988 ◽  
Vol 66 (1) ◽  
pp. 266-273 ◽  
Author(s):  
C. B. Murray ◽  
J. D. McPhail
Keyword(s):  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Coho Salmon ◽  
Incubation Temperature ◽  
Pacific Salmon ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Embryo Survival ◽  
Salmon Fry ◽  
Incubation Temperatures

Embryo and alevin survival, time to hatching and emergence, and alevin and fry size of five species of Pacific salmon (Oncorhynchus) were observed at five incubation temperatures (2, 5, 8, 11, and 14 °C). No pink (Oncorhynchus gorbuscha) or chum (O. keta) salmon embryos survived to hatching at 2 °C. Coho (O. kisutch) and sockeye (O. nerka) salmon had higher embryo survival at 2 °C than chinook (O. tschawytscha) salmon. At 14 °C, chum, pink, and chinook salmon had higher embryo survival than coho or sockeye salmon. In all species, peaks of embryo mortality occurred at specific developmental stages (completion of epiboly, eye pigmentation, and hatching). Alevin survival to emergence was high for all species, except for coho and pink salmon at 14 °C. Hatching and emergence time varied inversely with incubation temperature, but coho salmon hatched and emerged sooner at all temperatures than the other species. Coho and sockeye salmon alevins were larger at 2 °C, pink, chum, and chinook salmon alevins were larger at 5 and 8 °C. Coho salmon fry were larger at 2 °C, chinook and chum salmon fry were larger at 5 °C, and sockeye and pink salmon fry were larger at 8 °C. High incubation temperatures reduced fry size in all species. Each species of Pacific salmon appears to be adapted to different spawning times and temperatures, and thus indirectly to specific incubation temperatures, to ensure maximum survival and size and to maintain emergence at the most favorable time each year.

Review of the Rate of Growth and Mortality of Pacific Salmon in Salt Water, and Noncatch Mortality Caused by Fishing

1976 ◽  
Vol 33 (7) ◽  
pp. 1483-1524 ◽  
Author(s):  
W. E. Ricker
Keyword(s):  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Salt Water ◽  
Pink Salmon ◽  
Total Yield ◽  
Coastal Region ◽  
Natural Mortality ◽  
Time Of Year

Mortality (other than landed catch) caused by pelagic gillnetting is estimated to be equal to the catch, for salmon in their penultimate year of life, and equal to about a quarter of the catch for salmon in their final year of life. Mortality caused by trolling for coho (Oncorhynchus kisutch) and chinook salmon (O. tshawytscha) averages about one fish killed (mostly below legal size) for every two that are boated. The natural mortality rate for sockeye salmon (O. nerka) in their final year of life averages about 0.015 per mo and is somewhat more in earlier years of pelagic life; the greater part of natural mortality after the smolt stage occurs during the downstream migration and early months of "coastal" life. For coho and chinook the best natural mortality estimate for the last year of life is 0.013 per mo, and that for pink (O. gorbuscha) and chum (O. keta) is of the same order. Growth rates during the final growing season vary from 0.26 per mo for pink and coho salmon to 0.06 per mo for chinook in their 5th ocean yr. Gains from ceasing to take immature salmon on the high seas range up to 300% of the catch now being taken in that category, while for fish taken in their final year they range up to about 70%, depending on the time of year at which the fishing is done. Gains from transferring existing pelagic net fisheries to the coastal region would be 76% (North American sockeye) and 86% (Asian sockeye) of the weight of fish now caught pelagically. Gains in total yield of existing salmon fisheries (pelagic and coastal) are estimated as 78% for Asian pink salmon and 72% for Asian sockeye. The increase in weight of the total catch from discontinuing ocean trolling for Columbia River chinook salmon and increasing river fishing correspondingly is estimated tentatively as between 63 and 98%.

scholarly journals Pacific salmon abundance trends and climate change

2011 ◽  
Vol 68 (6) ◽  
pp. 1122-1130 ◽  
Author(s):  
James R. Irvine ◽  
Masa-aki Fukuwaka
Keyword(s):  
Climate Change ◽  
Pacific Ocean ◽  
North Pacific ◽  
Sockeye Salmon ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
North Pacific Ocean ◽  
Pink Salmon ◽  
The North ◽  
Abundance Trends

Abstract Irvine, J. R., and Fukuwaka, M. 2011. Pacific salmon abundance trends and climate change. – ICES Journal of Marine Science, 68: 1122–1130. Understanding reasons for historical patterns in salmon abundance could help anticipate future climate-related changes. Recent salmon abundance in the northern North Pacific Ocean, as indexed by commercial catches, has been among the highest on record, with no indication of decline; the 2009 catch was the highest to date. Although the North Pacific Ocean continues to produce large quantities of Pacific salmon, temporal abundance patterns vary among species and areas. Currently, pink and chum salmon are very abundant overall and Chinook and coho salmon are less abundant than they were previously, whereas sockeye salmon abundance varies among areas. Analyses confirm climate-related shifts in abundance, associated with reported ecosystem regime shifts in approximately 1947, 1977, and 1989. We found little evidence to support a major shift after 1989. From 1990, generally favourable climate-related marine conditions in the western North Pacific Ocean, as well as expanding hatchery operations and improving hatchery technologies, are increasing abundances of chum and pink salmon. In the eastern North Pacific Ocean, climate-related changes are apparently playing a role in increasing chum and pink salmon abundances and declining numbers of coho and Chinook salmon.

Challenges for Diadromous Fishes in a Dynamic Global Environment

2009 ◽  
Keyword(s):  
Chinook Salmon ◽  
Large Scale ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Pink Salmon ◽  
Commercial Catch ◽  
Atmospheric Processes ◽  
Energy Transfers ◽  
Salmon Production ◽  
The Impact

<em>Abstract</em>.-Pacific salmon <em>Oncorhynchus </em>spp. catches are at historic high levels. It is significant that one of the world's major fisheries for a group of species that dominates the surface waters of the subarctic Pacific is actually very healthy. Natural trends in climate are now recognized to cause large fluctuations in Pacific salmon production, as shown in historical records of catch and recent changes probably have been affected by greenhouse gas induced climate changes. Pink salmon <em>O. gorbuscha </em>and chum salmon <em>O. keta </em>production and catch has increased in the past 30 years and may continue in a similar trend for for the next few decades. Coho salmon <em>O. kisutch </em>and Chinook salmon <em>O. tshawytscha </em>catches have been declining for several decades, particularly at the southern end of their range, and they may continue to decline. In the 1970s, hatcheries were considered to be a method of adding to the wild production of coho and Chinook salmon because the ocean capacity to produce these species was assumed to be underutilized. Large-scale changes in Pacific salmon abundances are linked to changes in large-scale atmospheric processes. These large-scale atmospheric processes are also linked to planetary energy transfers, and there is a decadal scale pattern to these relationships. Pacific salmon production in general is higher in decades of intense Aleutian lows than in periods of weak Aleutian lows. Key to understanding the impact of climate change on Pacific salmon is understanding how the Aleutian low will change. Chinook and coho salmon are minor species in the total commercial catch, but important socially and economically in North America. A wise use of hatcheries may be needed to maintain abundances of these species in future decades.

Changes in the Average Size and Average Age of Pacific Salmon

1981 ◽  
Vol 38 (12) ◽  
pp. 1636-1656 ◽  
Author(s):  
W. E. Ricker
Keyword(s):  
Growth Rate ◽  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Gill Nets ◽  
Growing Seasons ◽  
Mean Size ◽  
Average Size

Of the five species of Pacific salmon in British Columbia, chinook salmon (Oncorhynchus tshawytscha) and coho salmon (O. kisutch) are harvested during their growing seasons, while pink salmon (O. gorbuscha), chum salmon (O. keta), and sockeye salmon (O. nerka) are taken only after practically all of their growth is completed. The size of the fish caught, of all species, has decreased, but to different degrees and over different time periods, and for the most part this results from a size decrease in the population. These decreases do not exhibit significant correlations with available ocean temperature or salinity series, except that for sockeye lower temperature is associated with larger size. Chinook salmon have decreased greatly in both size and age since the 1920s, most importantly because nonmaturing individuals are taken by the troll fishery; hence individuals that mature at older ages are harvested more intensively, which decreases the percentage of older ones available both directly and cumulatively because the spawners include an excess of younger fish. Other species have decreased in size principally since 1950, when the change to payment by the pound rather than by the piece made it profitable for the gill-netters to harvest more of the larger fish. Cohos and pinks exhibit the greatest decreases, these being almost entirely a cumulative genetic effect caused by commercial trolls and gill nets removing fish of larger than average size. However, cohos reared in the Strait of Georgia have not decreased in size, possibly because sport trolling has different selection characteristics or because of the increase in the hatchery-reared component of the catch. The mean size of chum and sockeye salmon caught has changed much less than that of the other species. Chums have the additional peculiarity that gill nets tend to take smaller individuals than seines do and that their mean age has increased, at least between 1957 and 1972. That overall mean size has nevertheless decreased somewhat may be related to the fact that younger-maturing individuals grow much faster than older-maturing ones; hence excess removal of the smaller younger fish tends to depress growth rate. Among sockeye the decrease in size has apparently been retarded by an increase in growth rate related to the gradual cooling of the ocean since 1940. However, selection has had two important effects: an increase in the percentage of age-3 "jacks" in some stocks, these being little harvested, and an increase in the difference in size between sockeye having three and four ocean growing seasons, respectively.Key words: Pacific salmon, age changes, size changes, fishery, environment, selection, heritability

Homing behavior and vertical movements of four species of Pacific salmon (Oncorhynchus spp.) in the central Bering Sea

1995 ◽  
Vol 52 (3) ◽  
pp. 532-540 ◽  
Author(s):  
Miki Ogura ◽  
Yukimasa Ishida
Keyword(s):  
Chinook Salmon ◽  
Bering Sea ◽  
Sockeye Salmon ◽  
Pacific Salmon ◽  
Pink Salmon ◽  
Depth Sensing ◽  
Compass Orientation ◽  
Homing Behavior ◽  
Vertical Movements ◽  
Strong Surface

Four sockeye salmon (Oncorhynchus nerka), two chum salmon (O. keta), three pink salmon (O. gorbuscha), and four Chinook salmon (O. tshawytscha) with depth-sensing ultrasonic transmitters were tracked in the central Bering Sea to examine migration in the open sea. Ground speeds of maturing sockeye, chum, and pink salmon were at 0.54–0.66 m/s (0.88–1.17 fork lengths/s). Chinook salmon, probably immature fish, moved more slowly (0.34 m/s). Maturing individuals moved in particular directions and maintained their ground speeds and directions during day and night. The results also suggested that salmon had a compass orientation ability functioning without celestial information. Sockeye, chum, and pink salmon showed strong surface preferences but chinook salmon swam deeper (30–35 m) than did the other species.

Downstream migrations of juvenile Pacific salmon (Oncorhynchus spp.) in a glacial transboundary river

1997 ◽  
Vol 54 (12) ◽  
pp. 2837-2846 ◽  
Author(s):  
Michael L Murphy ◽  
K V Koski ◽  
J Mitchel Lorenz ◽  
John F Thedinga
Keyword(s):  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Transboundary Rivers ◽  
Delayed Entry ◽  
Transboundary River ◽  
Spawning Areas ◽  
Seventh Order ◽  
Juvenile Pacific Salmon

Migrations of juvenile Pacific salmon (Oncorhynchus spp.) in the glacial Taku River (seventh order) were studied to assess movement from upriver spawning areas (in British Columbia) into lower-river rearing areas (in Alaska). Differences between fyke-net catches in the river and seine catches in the river's estuary indicated that many downstream migrants remained in the lower river instead of migrating to sea. In particular, age-0 coho salmon (O. kisutch) and chinook salmon (O. tshawytscha) moved downriver from May to November but were not caught in the estuary. Age-0 sockeye salmon (O. nerka), coho presmolts, and other groups delayed entry into the estuary after moving downriver. We tagged groups of juvenile coho (ages 0-2) from the fyke net with coded-wire to determine when they left the river. One-third of all tags recovered from sport and commercial fisheries occurred 2-3 years later, showing that many coho remained in fresh water for 1-2 years after moving to the lower river. Lower-river areas of large glacial rivers like the Taku River can provide essential rearing habitat for juvenile salmon spawned upriver and are important to consider in integrated whole-river management of transboundary rivers.

Levels of Constituents of Glycoproteins in the Sera of Pacific Salmon

1971 ◽  
Vol 28 (8) ◽  
pp. 1173-1179 ◽  
Author(s):  
M. D. Qureshi ◽  
R. V. Hledin ◽  
P. A. Anastassiadis ◽  
W. E. Vanstone
Keyword(s):  
Sialic Acid ◽  
Protein Content ◽  
Chinook Salmon ◽  
Bovine Serum ◽  
Sockeye Salmon ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Oncorhynchus Nerka ◽  
Limited Extent ◽  
Carbohydrate Complex

The levels of hexosamine, sialic acid, fucose, and protein in serum of sockeye salmon (Oncorhynchus nerka) and, to a limited extent, in sera of coho salmon (O. kisutch) and chinook salmon (O. tshawytscha) at two reproductive stages, were determined. Hexosamine, sialic acid, fucose, hexose, seromucoid, and protein content of sexually maturing (early) and mature (spawning) sockeye salmon were studied and a comparison was attempted with the corresponding composition of bovine serum. Content of the above serum constituents was lower in spawning than in maturing populations. Protein content was much less, hexosamine a little less, and sialic acid higher, in the sera of sockeye salmon than in bovine serum. The protein–carbohydrate complex of serum appeared to contain more hexosamine and much more sialic acid than the protein–carbohydrate complex of bovine serum. Furthermore, the sialic acid-to-hexosamine ratio was much higher in sera of salmon than in bovine serum. Some other sex and reproductive stage differences were detected and reported.

Suspended Sediment Particles Inside Gills and Spleens of Juvenile Pacific Salmon (Oncorhynchus spp.)

1993 ◽  
Vol 50 (3) ◽  
pp. 586-590 ◽  
Author(s):  
Dennis W. Martens ◽  
James A. Servizi
Keyword(s):  
Suspended Sediment ◽  
Sockeye Salmon ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Pink Salmon ◽  
X Ray Diffraction ◽  
Mineral Particles ◽  
Juvenile Pacific Salmon ◽  
Sediment Particles ◽  
Laboratory Exposure

Intracellular sediment particles were observed in the gills of underyearling coho salmon (Oncorhynchus kisutch) and pink salmon (O. gorbuscha) following laboratory exposure to Fraser River sediment. Gills of underyearling sockeye salmon (O. nerka), chinook salmon (O. tshawytscha), and coho exposed to a natural suspended sediment in Cultus Lake hatchery water also contained intracellular mineral particles. Mineral particles were seen in both epithelial and underlying gill filamental cells, and it is believed that these particles were phagocytosed by the former. Intracellular sediment particles were also observed in spleens of some sediment-exposed fish. Electron microscopy was used to measure gill particle sizes and X-ray diffraction analysis to identify eight minerals and one metal in the gills of sockeye previously exposed to suspended sediment.

A Relationship between Fraser River Discharge and Interannual Production of Pacific Salmon (Oncorhynchus spp.) and Pacific herring (Clupea pallasi) in the Strait of Georgia

1994 ◽  
Vol 51 (12) ◽  
pp. 2843-2855 ◽  
Author(s):  
Richard J. Beamish ◽  
Chrys-Ellen M. Neville ◽  
Barbara L. Thomson ◽  
Paul J. Harrison ◽  
Mike St. John
Keyword(s):  
River Discharge ◽  
Sockeye Salmon ◽  
River Flow ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Close Association ◽  
Pink Salmon ◽  
Pacific Herring ◽  
Fraser River ◽  
Clupea Pallasi

We identified years of anomalously high and low discharge from the Fraser River and compared these years with indices of anomalously high and low production of Pacific salmon (Oncorhynchus spp.) and Pacific herring (Clupea pallasi). For chinook (O. tshawytscha) and coho salmon (O. kisutch), we found that brood years that went to sea in a year when the Fraser River discharge was very high compared with the previous year virtually never had an index of production that was higher than the previous year. Similarly, brood years that went to sea in a year when the Fraser River discharge was very low compared with the previous year almost never had an index of productivity that was lower than the previous year. The analysis identified a weaker association between extreme discharge anomalies and chum salmon (O. keta) production. A close association was not found between extreme discharge anomalies and pink salmon (O. gorbuscha), sockeye salmon (O. nerka), or herring production. The relationships identify a connection between annual fluctuations in river flow and production of some marine fishes and may be of use in forecasting abundance changes.

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