Download or read book Estimation of U S Canada Border Age composition of Yukon River Chinook Salmon 1982 2006 written by Toshihide Hamazaki and published by . This book was released on 2018 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study estimated age and sex composition of Canadian-origin Yukon River Chinook salmon at the United States (U.S.)-Canada border from 1982 to 2006. In 2012, the Joint Technical Committee of the Yukon River Panel (JTC) adopted a change to the assessment methods used to estimate U.S.-Canada border passage of Canadian-origin Chinook salmon from a fish wheel mark-recapture operated by Fisheries and Oceans Canada (DFO) to a sonar with a gillnet test fishery at Eagle operated jointly by the Alaska Department of Fish and Game (ADF&G) and DFO since 2005. Because the 2 fish capturing methodologies (fish wheel versus gillnet) resulted in different age-sex compositions, it was necessary to adjust the age-sex composition assessed by the fish wheel to those of the gillnet test fishery. Age, sex, and length (ASL) data were collected from fish sampled using both methods from 2005 to 2012, except 2009. Using 2007, 2008, 2010-2012 data, fish wheel age-sex compositions were adjusted using 2 methods: (1) age-sex selectivity and (2) length selectivity, and compared to the age-sex compositions observed in the gillnet test fishery. Although both methods performed similarly, the age-sex selectivity method was slightly better than the length selectivity method to adjust age-sex composition. However, because of uncertainties about the 2007-2012 data representing historical fish wheel data, the length selectivity method was chosen to adjust the 1982-2006 age-sex composition. Length selectivity converted 1982-2006 age-sex proportion are presented, and the uncertainties and limitations are discussed.
Download or read book Bering Sea Chinook Salmon Bycatch Management Regulatory Impact Review initial Regulatory Flexibility Analysis written by and published by . This book was released on 2009 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Salmon Age and Sex Composition and Mean Lengths for the Yukon River Area 2006 written by James Bales and published by . This book was released on 2008 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Report discusses biological data collected from Pacific salmon runs at 35 locations along the Yukon River drainage in 2006.
Download or read book Salmon Age and Sex Composition and Mean Lengths for the Yukon River Area 2014 written by Shane M. Eaton and published by . This book was released on 2016 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biological data were collected from Chinook (Oncorhynchus tshawytscha), summer chum (O. keta), fall chum (O. keta), and coho (O. kisutch) salmon at 19 locations along the U.S. portion of the Yukon River drainage in 2014. Age, sex, and length (ASL) data were obtained from 2,969 Chinook, 4,637 summer chum, 3,120 fall chum, and 1,654 coho salmon from commercial and subsistence harvests, as well as test fisheries and escapement projects. Samples were collected from salmon caught with gillnets, dip nets, fish wheels, beach seines, weir traps, and from hand-picked carcass. Where available, escapement estimates from weir projects were separated into temporal segments (strata) and commercial harvests were separated by fishing periods. The ASL data collected during the corresponding stratum or period was applied to the corresponding escapement estimate or commercial harvest to generate estimates of proportions and numbers by age and sex. At test fishery projects ASL data were stratified into quartiles based on catch per unit effort (CPUE), commercial period, or mesh size. In 2014, age-1.3 Chinook salmon predominated from all of the test fishery and escapement projects; and most of the subsistence harvest samples. At many long standing projects 5-year-old (age-1.3 and age-2.2) Chinook salmon percentages were above the long-term and 5-year averages, whereas the 4-year-old (age-1.2 and age-2.1) and 6-year-old (age-1.4 and age-2.3) percentages were near or below the long-term and 5-year averages. Both summer and fall chum salmon samples were primarily composed of age-0.3 and age-0.4 fish. Age-2.1 coho salmon predominated in the commercial and test fishery samples.
Download or read book Yukon River Chinook Salmon Aging Consistency written by Larry DuBois and published by . This book was released on 2010 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accurate and consistent age estimation is an inherent assumption of historical age trend analysis. During the years that the Alaska Department of Fish and Game (ADF&G) has collected scales from Yukon River Chinook salmon Oncorhynchus tshawytscha many different readers have interpreted scale growth patterns and assigned ages. This study assessed the percent agreement and temporal consistency by ADF&G in estimating Chinook salmon ages from scales.
Download or read book Age Composition and Escapement of Chinook Salmon in the Karluk Ayakulik and Chignik Rivers Alaska 2006 2007 written by Donn Tracy and published by . This book was released on 2012 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Yukon River Salmon Enumeration Eagle AK 2022 written by Jody D. Lozori and published by . This book was released on 2022 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: Both the Alaska Department of Fish and Game (ADF&G) and the Canadian Department of Fisheries and Oceans (DFO) actively manage Chinook salmon Oncorhynchus tshawytscha and fall chum salmon O. keta fisheries in the Yukon River. Alaska is obligated to manage Canadian-origin Yukon River Chinook and fall chum salmon stocks according to precautionary, abundance-based harvest-sharing principles set by the Yukon River Salmon Agreement (Yukon River Panel 2004). This negotiated agreement represents an international commitment to the restoration, conservation, and management of Yukon River salmon, and is based on escapement management . Of importance to salmon management on the Yukon River is the ability to accurately assess the numbers of Chinook and fall chum salmon migrating through the U.S./Canada border. This project employs split-beam and imaging sonar equipment on the Yukon River to generate inseason passage estimates of Chinook and fall chum salmon migrating across the U.S./Canada border. Additionally, drift gillnetting is conducted daily to monitor species composition, and to collect biological data used in characterizing Chinook and fall chum salmon runs. The project is located approximately 30 km downstream from the U.S./Canada Border (Figures 1 and 2) and is scheduled to operate continuously from approximately July 1 through October 10 annually. This project has been fully operational since 2006 (Dunbar and Crane 2007).
Download or read book Estimates of Total Abundance Exploitation Rate and Migratory Timing of Chinook Salmon Runs in the Yukon River 1982 1986 written by Linda K. Brannian and published by . This book was released on 1990 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Report on estimates of total abundance (total run size), exploitation rate (maximum sustainable exploitation rate), and migration timing (lower and middle runs, Alaska and upper runs, Canadian origin) of chinook salmon (Oncorhynchus tschawytscha Walbaum) in the Yukon river, Alaska between 1982 and 1986.
Download or read book Fall Chinook Oncorhynchus Tshawytscha written by Jim Waldvogel and published by . This book was released on 2006 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Age analysis for 22 years (1980 excluded) showed that the overall percentages for female spawners was 53% (4-year olds), 38% (3-year olds), and 9% (5-year olds). The age composition of male spawners showed a high degree of variability throughout the study. Male chinook of age 2, 3 and 4 were dominant annually, but 5- and 6- year old fish were present in most spawning seasons. All chinook carcasses from which scales were collected were also measured for length (over 120 samples in 22 years). Decreases in mean length were documented for all age classes for each of the El Nino episodes that occurred during the study (1982-1984; 1992-1993; 1997-1998). The decreases in mean length appeared to carry forward for each cohort's age class. The total number of chinook redds was tabulated by counting "fresh" redds during weekly spawning surveys. The mean number of redds was 117 for the 23-year period with a mean of 0.9 redds per adult salmon or 1.8 redds per female.
Download or read book Potential Causes of Size Trends in Yukon River Chinook Salmon Populations written by and published by . This book was released on 2006 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concerns regarding the size and sex composition of Yukon River Chinook salmon, Oncorhynchus tshawytscha, have been expressed in public meetings for over a decade. However, reports of small size and low numbers of females have become increasingly common in recent years, and apprehension over the long-term health of the stock has grown within the drainage. In response to these reports, the Salmon Size Subcommittee of the US/Canada Yukon River Joint Technical Committee was formed and charged with advising the Committee, and thereby the US/Canada Yukon River Panel, with respect to changes in chinook salmon age, sex, and size composition. This report, which summarizes the findings of prior investigations and the scientific literature on factors that influence salmon morphology, represents the first product of the subcommittee.
Download or read book Spawning Escapement of Chinook Salmon in the Stikine River 2022 2024 written by Kristin Courtney and published by . This book was released on 2022 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: The inriver abundance of large (fish =660 mm mid eye to tail fork [METF] length) Chinook salmon Oncorhynchus tshawytscha above the U.S./Canada border (border) will be estimated annually from 2022 to 2024 in the Stikine River, near Wrangell, Alaska. A modified Petersen 2-event mark–recapture project will be conducted using drift gillnets to mark large Chinook salmon in the first event, and collection of samples in the Canadian commercial fishery, Little Tahltan River video weir, and on the spawning grounds will serve as the second event. Additional project objectives are to a) estimate the annual spawning escapement of large Chinook salmon above the border, b) estimate the age, sex, and length composition of both the inriver run and spawning escapement, and c) estimate the proportion of large radiotagged Chinook salmon that cross the border. The Alaska Department of Fish and Game (ADF&G) and Fisheries and Oceans Canada (DFO) use these data to make terminal and regional management decisions, and the Pacific Salmon Commission (PSC) uses the data for coastwide management and stock assessment through the Chinook Technical Committee (CTC 2021).
Download or read book Estimation of the Abundance of Chinook Salmon Oncorhynchus Tshawytscha in the Upper Yukon River Basin Using Mark recapture Methods 1990 95 written by and published by . This book was released on 2002 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fisheries & Oceans Canada has conducted mark-recapture studies on adult Yukon River chinook salmon since 1982. In some of these studies, up to 2,174 upstream migrants were spaghetti tagged annually at two fishwheels located just upstream from the Canada/US border. Recaptures were made in a commercial fishery upstream. This report presents results from the chinook mark-recapture program for 1990 to 1995. Background on the Yukon River, its chinook population & fishery, and mark-recapture & data analysis methods begins the report. Results are presented with regard to the biological characteristics of salmon captured, abundance estimates using three estimation methods, fishery catches & spawning escapement, harvest rates, and migration rates. The final section discusses problems with respect to the abundance estimators used and makes recommendations for further research.
Download or read book Origins of Chinook Salmon in the Yukon River Fisheries 2013 written by Larry DuBois and published by . This book was released on 2016 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The stock and age composition of Chinook salmon Oncorhynchus tshawytscha harvest within the Yukon River drainage was estimated for 2013. Stock composition was estimated by genetic analysis for 3 geographically-based stock groups termed Lower, Middle, and Upper. Stock composition estimates from sampled fish were applied to specific harvests across all age classes. Ages of sampled fish were determined from scales; age composition was estimated from the sample proportions in each age class. Age composition estimates were applied to specific harvests across all stock groups. The total estimated Yukon River harvest in 2013 was 13,345 Chinook salmon; of these 13.4% were estimated to be of Lower, 21.0% Middle, and 65.6% Upper stock group origin. On average over all harvests, age-1.4 fish dominated the harvest at 44.5%, age-1.3 fish were 37.2%, age-1.2 fish were 15.3%, and other age classes combined were 3.0% of the total.
Download or read book Sonar Estimation of Chinook Salmon in the Yukon River Near Eagle Alaska 2005 written by Holly C. Carroll and published by . This book was released on 2007 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of a Yukon River sonar project, which provided estimates of chinook salmon passage from July 12-August 10, 2005, on the Yukon River near the Alaska/Canada border.
Download or read book Origins of Chinook Salmon in the Yukon River Fisheries 2009 written by Larry DuBois and published by . This book was released on 2013 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reports on estimations of the stock composition of all harvests and test fishery catches of Chinook salmon, Oncorhynchus tshawytscha, within the Yukon River drainage in 2009. Stock composition was estimated for 3 geographically-based stock groups termed Lower, Middle, and Upper, and commercial and subsistence harvest age compositions were estimated from aged scales collected. Age compositions from sampled fish, in combination with genetic stock estimates, were used to estimate the stock composition for each age class. Also includes historical data from 1981-2008.
Download or read book Exploratory Analysis written by Gene J. Sandone and published by . This book was released on 2010 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: After decades of using the DFO mark-recapture border program as the sole U.S./Canada border passage estimator oil the Yukon River, the cooperative ADF&G-NOAA drainage-wide radio telemetry project and ADF&G-DFO sonar projects provided independent estimates of border passage for 2002-2004 and 2005- 2007, respectively. Marked and variable differences between the annual DFO mark-recapture estimates and estimates derived from radio telemetry and sonar projects strongly suggests that the DFO mark- recapture estimate was biased low and a new sonar-based escapement goal was necessary. An exploratory analysis was initiated to reconstruct the historic drainage escapement database and make it compatible with new sonar-based escapement estimates. Analyses were conducted that ranged from simple scaling of historical data to more robust regression models. Seventeen escapement databases were created through these analyses. Ultimately, four escapement databases, reconstructed from drainage escapements derived from radio telemetry and sonar projects (2002-2007) and regressed against escapement indices, were considered viable candidates. A secondary goal of these analyses was to investigate potential escapement goal ranges based oil the viable escapement databases. Interestingly, all Sustainable Escapement Goal (SEG) ranges and Marcov Table analysis indicated similar escapement goals for all four reconstructed escapement database scenarios. Spawner-recruit statistics were also very similar. Therefore, two escapement goal recommendations were suggested: 1) Set a conservative escapement goal range that reflected all escapement database scenarios, 40,000 to 60,000 Chinook salmon, and 2) Do not select a reconstructed escapement database for the period 1982-2001, but build on the current escapement database derived from radio-telemetry estimates (2002-2004) and sonar counts (2005-present).
Download or read book Estimation of the Annual In river Run Strength of Yukon River Chinook Salmon Based Upon the Migratory Time Density Function Effect of Commercial Catch and Effort on Test Fishery Catches and Predicted Migratory Rates of Chinook Salmon written by John E. Clark and published by . This book was released on 1983 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Quantitatively contrast[s] test fishery catches on days of no commercial effort with test fishery catches during commercial openings"--P. 2.
