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Book Short term Survival of Fall Chinook and Coho Salmon Captured by Purse Seines in the Lower Columbia River 2017

Download or read book Short term Survival of Fall Chinook and Coho Salmon Captured by Purse Seines in the Lower Columbia River 2017 written by Ben Cox (Fisheries biologist) and published by . This book was released on 2019 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Co-managers of the lower Columbia River have been exploring the viability of alternative commercial fishing gears, including beach and purse seines, to allow the selective harvest of hatchery-origin fall Chinook Oncorhynchus tshawytscha and Coho Oncorhynchus kisutch salmon. The viability of purse seines as a selective fishing gear depends on the expected survival rate of released fish. In autumn 2017, the Washington Department of Fish and Wildlife implemented a holding experiment to estimate short-term survival of Chinook and Coho salmon following capture in purse seines. Treatment fish were captured by purse seines in Columbia River Commercial Fishing Zone 5 and control fish were obtained from the Adult Fish Facility at Bonneville Dam. Paired groups of treatment and control fish were held together in net pens and their survival monitored for 48 h after capture. Mixed-effects logistic regression models were developed to explore the influence of covariates including of water temperature, body size, sort time, transport time, and reflex impairment on the probability of survival. Model selection results supported simple models and none of the covariates considered were found to significantly affect survival during this experiment. Short-term (48 h) survival for adult Chinook and Coho salmon captured in purse seines was estimated to be 97.9% (94.0 – 99.3%; 95% CL) and 98.1% (85.7– 99.8%; 95% CL), respectively.

Book Growth and Degree of Maturity of Chinook Salmon in the Ocean

Download or read book Growth and Degree of Maturity of Chinook Salmon in the Ocean written by Willis Horton Rich and published by . This book was released on 1925 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Fluctuations in Abundance of Columbia River Chinook Salmon 1928 54

Download or read book Fluctuations in Abundance of Columbia River Chinook Salmon 1928 54 written by Harold A. Gangmark and published by . This book was released on 1956 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Factors Affecting the Abundance of Fall Chinook Salmon in the Columbia River

Download or read book Factors Affecting the Abundance of Fall Chinook Salmon in the Columbia River written by Jack M. Van Hyning and published by . This book was released on 1968 with total page 848 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study of the population ecology of Columbia River fall chinook salmon, Oncorhynchus tshawytscha (Walbaum), was made in an attempt to determine the cause of a serious decline in this run which occurred in the early 1950's. Fluctuations in abundance of major salmon runs the North Pacific were examined to detect any coastwide pattern. Only chinook salmon in Cook Inlet, Alaska, and chum salmon from Oregon to southwestern Alaska showed a similar trend. The following life history stages broken down into pre- and post-decline years were examined: (1) marine life including distribution and migration, growth and maturity, survival rate, oceanography, and commercial and sport fisheries; (2) upstream migration including river fisheries, gear selectivity, size and age composition of the run, escapement, and influence of dams, diseases, and water quality; (3) reproduction and incubation including spawning areas and spawning and incubation conditions; and (4) downstream migration which included predation, dams and reservoirs, diseases, flow, turbidity and temperature, and estuary life. Salient points of the analysis were: (1) a change in the maturity and survival pattern based on tagged and fin-clipped fish recovered before and after 1950; (2) a significant negative correlation between sea-water temperature during a year class' first year at sea and subsequent survival; (3) a large increase in the ocean fisheries coincident with the decline in the run; (4) catch-effort statistics of the ocean fishery show a near classic example of the effect of overexploitation; (5) estimates of the contribution of Columbia River chinook to the ocean fisheries based on tag recoveries could be underestimates rather than overestimates; (6) a significant inverse correlation between estimated ocean catch of Columbia River fall chinook and numbers entering the river; (7) size and age composition of the ocean and river catches decreased coincident with the decline in the run; (8) the gill-net fishery shows little size selectivity by age, size, or sex in the dominant group; (9) fluctuations in abundance of hatchery stocks are related to differences in survival between fingerling and adult; (10) hatchery, lower river, and upriver populations fluctuate in abundance in much the same pattern; (11) optimum escapement is between 90,000 and 100,000 adults, a value that was exceeded during most years; (12) a highly significant negative correlation between numbers of spawners and return per spawner; (13) most of the early dams had no direct effect on fall chinook and the decline in productivity occurred when river conditions were relatively stable; (14) temperatures at time of migration and spawning for fall chinook have not increased enough to be a serious mortality factor; (15) little relationship between flow, turbidity, and temperature at time of downstream migration and subsequent return was evident except that high temperatures and high flows (and turbidities) tended to produce poorer runs during certain time periods; and (16) predation and delay of smolts in reservoirs are largely unknown factors, but circumstantial evidence suggests that they were not important in regulating fall chinook numbers during the period of the study. Finally, variables that appeared to bear some relationship to fluctuations in abundance of fall chinook were submitted to multiple regression analysis. For the predecline period (1938-46 brood years), sea-water temperature and ocean troll fishing effort were significant variables (R2 = 0.74). For post decline years (1947-59 broods), troll had the most influence on total return with ocean temperature and escapement having lesser effects. For the combined years, troll intensity and ocean temperature were the significant variables (R2 = 0.572). Entering interaction of river flow at downstream migration with the other variables brought R2 to 0.754 which means that 75% of the variability in the returning run could be accounted for by these three factors. Return per spawner was so heavily influenced by numbers of spawners that the other factors assumed negligible importance. Equations were derived that predicted the returning run in close agreement with the actual run size. Substituting a low and constant troll fishing effort in the equation resulted in the predicted run maintaining the average predecline level. The increase in ocean fishing was the main contributor to the decline of the Columbia River fall chinook run as shown by correlation, by analogy, and by the process of elimination. To demonstrate why other chinook runs have not shown similar declines, it was shown that due to several unique features in Columbia River fall chinook life history they are exposed to much more ocean fishing than other populations. It was emphasized that these conclusions should not be extrapolated to the future or to other species or runs of salmon.

Book Survival of Subyearling Fall Chinook Salmon in the Free flowing Snake River and Lower Snake River Reservoirs in 2003 and from McNary Dam Tailrace to John Day Dam Tailrace in the Columbia River from 1999 to 2002 1999 2003 Technical Report

Download or read book Survival of Subyearling Fall Chinook Salmon in the Free flowing Snake River and Lower Snake River Reservoirs in 2003 and from McNary Dam Tailrace to John Day Dam Tailrace in the Columbia River from 1999 to 2002 1999 2003 Technical Report written by Steven G. Smith and published by . This book was released on 2004 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report results from an ongoing study of survival and travel time of subyearling fall Chinook salmon in the Snake River during 2003 and in the Columbia River during 1999-2002. Earlier years of the study included serial releases of PIT-tagged hatchery subyearling Chinook salmon upstream from Lower Granite Dam, but these were discontinued in 2003. Instead, we estimated survival from a large number of PIT-tagged fish released upstream from Lower Granite Dam to evaluate transportation from Snake River Dams. During late May and early June 2003, 68,572 hatchery-reared subyearling fall Chinook salmon were PIT tagged at Lyons Ferry Hatchery, trucked upstream, acclimated, and released at Couse Creek and Pittsburg Landing in the free-flowing Snake River. We estimated survival for these fish from release to Lower Granite Dam tailrace. In comparison to wild subyearling fall Chinook salmon PIT tagged and released in the free-flowing Snake River, the hatchery fish we released traveled faster and had higher survival to Lower Granite Dam, likely because of their larger size at release. For fish left in the river to migrate we estimated survival from Lower Granite Dam tailrace to McNary Dam tailrace. Each year, a small proportion of fish released are not detected until the following spring. However, the number of fish released in 2003 that overwintered in the river and were detected as they migrated seaward as yearlings in 2004 was small (

Book Reports by the United States and Canada on the Status Ocean Migrations and Exploitation of Northeast Pacific Stocks of Chinook and Coho Salmon to 1964 Report by the United States section v 2 Report by the Canadian section

Download or read book Reports by the United States and Canada on the Status Ocean Migrations and Exploitation of Northeast Pacific Stocks of Chinook and Coho Salmon to 1964 Report by the United States section v 2 Report by the Canadian section written by Informal Committee on Chinook and Coho and published by . This book was released on 1969 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Post Release Attributes and Survival of Hatchery and Natural Fall Chinook Salmon in the Snake River

Download or read book Post Release Attributes and Survival of Hatchery and Natural Fall Chinook Salmon in the Snake River written by and published by . This book was released on 2001 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes results of research activities conducted in 1999 and years previous. In an effort to provide this information to a wider audience, the individual chapters in this report have been submitted as manuscripts to peer-reviewed journals. These chapters communicate significant findings that will aid in the management and recovery of fall chinook salmon in the Columbia River Basin. Abundance and timing of seaward migration of Snake River fall chinook salmon was indexed using passage data collected at Lower Granite Dam for five years. We used genetic analyses to determine the lineage of fish recaptured at Lower Granite Dam that had been previously PIT tagged. We then used discriminant analysis to determine run membership of PIT-tagged smolts that were not recaptured to enable us to calculate annual run composition and to compared early life history attributes of wild subyearling fall and spring chinook salmon. Because spring chinook salmon made up from 15.1 to 44.4% of the tagged subyearling smolts that were detected passing Lower Granite Dam, subyearling passage data at Lower Granite Dam can only be used to index fall chinook salmon smolt abundance and passage timing if genetic samples are taken to identify run membership of smolts. Otherwise, fall chinook salmon smolt abundance would be overestimated and timing of fall chinook salmon smolt passage would appear to be earlier and more protracted than is the case.

Book The Relationship Between Survival of Columbia River Fall Chinook Salmon and In River Environmental Factors

Download or read book The Relationship Between Survival of Columbia River Fall Chinook Salmon and In River Environmental Factors written by and published by . This book was released on 1996 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project analyzes in greater detail the coded-wire-tag (CWT) returns of Priest Rapids Hatchery fall chinook for the years 1976--1989 initially begun by Hilborn et al. (1993a). These additional analyses were prompted by suggestions made by peer reviews of the initial draft report. The initial draft and the peer review comments are included in this final report (Appendices A and B). The statistical analyses paired Priest Rapids stock with potential downriver reference stocks to isolate in-river survival rates. Thirty-three potential reference stocks were initially examined for similar ocean recovery rates; the five stocks with the most similar recovery patterns (i.e., Bonneville Brights, Cowlitz, Gray's River, Tanner Creek, and Washougal) to the Priest Rapids stock were used in the subsequent analysis of in-river survival. Three alternate forms of multiple regression models were used to investigate the relationship between predicted in-river survival and ambient conditions. Analyses were conducted with and without attempts to adjust for smolt transportation at McNary Dam. Independent variables examined in the analysis included river flows, temperature, turbidity, and spill along with the total biomass of hatchery releases in the Columbia-Snake River Basin.

Book Effect of Increased Water Temperatures on the Survival of Spring and Fall Juvenile Chinook Salmon Oncorhynchus Tschawytscha from the Lower Columbia River

Download or read book Effect of Increased Water Temperatures on the Survival of Spring and Fall Juvenile Chinook Salmon Oncorhynchus Tschawytscha from the Lower Columbia River written by Theodore H. Blahm and published by . This book was released on 1970 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Origin and Migration of Washington s Chinook and Coho Salmon

Download or read book Origin and Migration of Washington s Chinook and Coho Salmon written by Samuel G. Wright and published by . This book was released on 1968 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Survival of Hatchery Subyearling Fall Chinook Salmon in the Free Flowing Snake River and Lower Snake River Reservoirs 1998 2001 Summary Report

Download or read book Survival of Hatchery Subyearling Fall Chinook Salmon in the Free Flowing Snake River and Lower Snake River Reservoirs 1998 2001 Summary Report written by and published by . This book was released on 2002 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report results from four years (1998-2001) of an ongoing study of survival and travel time of subyearling fall chinook salmon in the Snake River. We report analyses of associations among river conditions and survival and travel time estimates, which include data from 1995 through 1997. At weekly intervals from early June to early July each year (mid-May to late June in 2001), hatchery-reared subyearling fall chinook salmon were PIT tagged at Lyons Ferry Hatchery, trucked upstream, acclimated, and released above Lower Granite Dam at Pittsburgh Landing and Billy Creek on the Snake River and at Big Canyon Creek on the Clearwater River. Each year, a small proportion of fish released were not detected until the following spring. However, the number that overwintered in the river and migrated seaward as yearlings the following spring was small and had minimal effect on survival estimates. Concurrent with our studies, a number of subyearling fall chinook salmon that reared naturally in the Snake River were caught by beach seine, PIT tagged, and released. We compared a number of characteristics of hatchery and wild fish. Hatchery and wild fish were similar in 2001, and from 1995 through 1997. Results for 1998 through 2000 showed some relatively large differences between hatchery and wild fish. However, recent information suggests that a considerable proportion of wild subyearling chinook salmon migrating in a given year may actually be stream-type (spring/summer), rather than ocean-type (fall) fish, which may account for some of the differences we have observed.