Download or read book Stock Assessment Study of Chilkoot Lake Sockeye Salmon 2016 2019 written by Shane R. Ransbury and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: From 2016 to 2019, the Alaska Department of Fish and Game, Division of Commercial Fisheries, continued a stock assessment program that began in 1976 to estimate escapements and harvests of Chilkoot Lake sockeye salmon (Oncorhynchus nerka). Sockeye salmon were counted through a weir near the outlet of Chilkoot Lake, and age, length, and sex data were collected and analyzed each year. Sockeye salmon escapements at the weir were 86,721 fish in 2016, 43,098 fish in 2017, 85,463 fish in 2018, and 140,378 fish in 2019, all of which fell within or exceeded the sustainable escapement goal range of 38,000–86,000 fish. Ocean-age-3 sockeye salmon (ages 1.3 and 2.3 combined) of both sexes were the shortest in length since scale sampling began in 1982. The stock compositions of sockeye salmon harvested annually in the District 15 commercial drift gillnet fishery were estimated through scale pattern analysis (2016) and genetic stock identification (2017–2019). Estimated commercial harvests of Chilkoot Lake sockeye salmon were 119,843 fish in 2016, 1,933 fish in 2017, 33,969 fish in 2018, and 149,586 fish in 2019. Estimated harvest rates (including subsistence and sport harvests) were 59% in 2016, 9% in 2017, 31% in 2018, and 52% in 2019. Estimated fall sockeye salmon fry populations at Chilkoot Lake were 42% above average in 2016, 45% below average in 2017, and at or slightly below average in 2018 and 2019, respectively. Average May–September zooplankton density and biomass at Chilkoot Lake were nearly double the long-term average, and zooplankton density in 2019 and biomass in 2016 were the highest recorded since sampling began in 1987.

Download or read book Stock Assessment Study of Chilkoot Lake Sockeye Salmon 2020 2021 written by Shelby M. Flemming and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2020 and 2021, the Alaska Department of Fish and Game, Division of Commercial Fisheries, continued a stock assessment program that began in 1976 to estimate escapements and harvests of Chilkoot Lake sockeye salmon (Oncorhynchus nerka). Sockeye salmon were counted through a weir near the outlet of Chilkoot Lake, and age, length, and sex data were collected and analyzed each year. Sockeye salmon escapements at the weir were 60,218 fish in 2020 and 98,672 fish in 2021, which fell within or exceeded the sustainable escapement goal range of 38,000–86,000 fish. Age-1.2 male sockeye salmon in 2020 were larger than the 1982–2019 average, whereas both male and female fish of other ages fell below this average. Genetic stock identification was conducted to determine the stock composition of sockeye salmon harvested annually in the District 15 commercial drift gillnet fishery. Estimated commercial harvests of Chilkoot Lake sockeye salmon were 24,878 fish in 2020, and 50,219 fish in 2021. Estimated harvest rates (including subsistence and excluding sport harvests) were 32% in 2020 and 35% in 2021, and Chilkoot Lake sockeye salmon accounted for an estimated 50% (2020) and 59% (2021) of the annual commercial sockeye salmon harvest in District 15. The estimated fall sockeye salmon fry population at Chilkoot Lake was 66% below average in 2020 (no surveys were conducted in 2021). Average May–September zooplankton density and biomass at Chilkoot Lake were above average in 2020 and below average in 2021.

Download or read book Stock Assessment Study of Chilkoot Lake Sockeye Salmon 2003 2015 written by Julie L. Bednarski and published by . This book was released on 2016 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: From 2013 to 2015, the Alaska Department of Fish and Game, Division of Commercial Fisheries, continued a stock assessment program that begun in 1976 to estimate escapements and harvests of Chilkoot Lake sockeye salmon (Oncorhynchus nerka). Sockeye salmon were counted through a weir near the outlet of Chilkoot Lake, and age, length, and sex data were collected and analyzed each year. Sockeye salmon escapements at the weir were 46,140 fish in 2013, 105,058 fish in 2014, and 71,515 fish in 2015. Visual scale pattern analysis was conducted to determine the proportion of Chilkoot sockeye salmon harvested annually in the District 15 commercial drift gillnet fishery. Estimated commercial drift gillnet harvests of Chilkoot sockeye salmon were 23,111 fish in 2013, 110,487 fish in 2014, and 33,085 fish in 2015. Estimated harvest rates were 36% in 2013, 52% in 2014, and 46% in 2015. In addition, zooplankton and hydroacoustic surveys were conducted in Chilkoot Lake and analyzed each year.

Download or read book Operational Plan written by Nicole L. Zeiser and published by . This book was released on 2020 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Chilkoot Lake sockeye salmon (Oncorhynchus nerka) run, which spawns near Haines, is one of the largest in Southeast Alaska and contributes substantially to harvests in the District 15 commercial drift gillnet fishery in Lynn Canal. This operational plan outlines objectives, methods, and timelines for conducting sockeye salmon stock assessment designed to (1) estimate annual escapement and harvest, (2) provide information for inseason fishery management, and (3) reconstruct runs and assess stock status. The Chilkoot Lake run is managed for a biological escapement goal of 38,000–86,000 fish, which is enumerated through a standard picket weir located just downstream of the lake outlet. Weir counts of sockeye salmon are compared to weekly escapement targets to determine inseason run strength. Genetic mixed stock analysis of weekly sockeye salmon harvests in the District 15 commercial drift gillnet fishery provides stock composition estimates that also guide inseason management of the fishery. Biological sampling, along with escapement enumeration and stock-specific harvest data, allows for total run reconstruction required for escapement goal review.

Download or read book Stock Assessment Study of Chilkat Lake and River Sockeye Salmon 2017 2020 written by Shane R. Ransbury and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: From 2017 to 2020, the Alaska Department of Fish and Game, Division of Commercial Fisheries, conducted stock assessment programs to estimate the escapement and harvest of Chilkat Lake sockeye salmon (Oncorhynchus nerka). Escapement was estimated with a Dual-frequency Identification Sonar (DIDSON) and weir near the outlet of Chilkat Lake, and age, length, and sex data were collected and analyzed each year. Sockeye salmon escapements, based on expanded DIDSON counts, were 88,197 fish in 2017, 108,047 fish in 2018, 136,091 fish in 2019, and 50,746 fish in 2020. Estimated escapements fell within the biological escapement goal range of 70,000–150,000 sockeye salmon in all but one year (2020). A pair of fish wheels were operated on the Chilkat River to provide inseason information on Chilkat sockeye salmon run strength to assist in management of the District 15 commercial drift gillnet fishery. Genetic stock identification was conducted to determine the stock composition of sockeye salmon harvested annually in the District 15 commercial drift gillnet fishery. Estimated commercial harvests of Chilkat Lake sockeye salmon were 5,698 fish in 2017, 19,235 fish in 2018, 40,935 fish in 2019, and 8,776 fish in 2020. Estimated annual harvest rates (not including subsistence or sport harvests) ranged from 6.1% (2017) to 23.1% (2019), and Chilkat Lake sockeye salmon accounted for an estimated 14.3% (2017) to 23.5% (2018) of the annual commercial sockeye salmon harvest in District 15. Zooplankton populations at Chilkat Lake have improved steadily since the late 2000s; historical peaks in the abundance of copepods and cladocerans (particularly Daphnia), the preferred prey of juvenile sockeye salmon, were observed in 2020 and 2019, respectively.

Download or read book A Comprehensive Review of Chilkat Lake and River Sockeye Salmon Stock Assessment Studies written by Julie Bednarski and published by . This book was released on 2017 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 1967 the Alaska Department of Fish and Game, Division of Commercial Fisheries, has operated a stock assessment program to estimate escapements and harvests of Chilkat sockeye salmon (Oncorhynchus nerka). Sockeye salmon were counted through a weir near the outlet of Chilkat Lake, and age, length, and sex data were collected and analyzed each year. Since 1994, mark-recapture studies were conducted to estimate Chilkat sockeye salmon escapements. Since the start of the 2008 season, DIDSON sonar has been used at the weir site to directly enumerate adult sockeye salmon escapement into Chilkat Lake. Visual scale pattern analysis was conducted to determine the proportion of Chilkat sockeye salmon harvested annually in the District 15 commercial drift gillnet fishery. In addition, limnological sampling was conducted in Chilkat Lake and analyzed each year. The intent of this report was to review Chilkat sockeye salmon stock assessment data from 1971 to 2016. The visual and DIDSON weir counts provide an index of escapement; however concerns regarding mark-recapture as a reliable index of abundance lead us to recommend eliminating mark-recapture studies in 2017 and, instead, maintain the DIDSON to estimate escapement into Chilkat Lake. We also recommend reviewing the current Chilkat Lake biological escapement goal to ensure that the goal and escapement estimates are in the same units, which is currently based on mark-recapture units. An average of 77,800 Chilkat Lake sockeye salmon were harvested annually in the District 15 commercial drift gillnet fishery (1976-2016). A comparison of historical fish wheel counts to Chilkat Lake escapement estimates demonstrates that the fish wheel project provides a rough indication of Chilkat Lake run strength. Zooplankton samples from Chilkat Lake were composed primarily of one species of copepod (Cyclops columbianus) and three species of cladocerans (Bosmina longerostris, Daphnia longiremus, and Daphnia rosea).

Download or read book Chilkoot Lake Sockeye Salmon Stock Status and Escapement Goal Review written by Rich Brenner and published by . This book was released on 2018 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chilkoot Lake, located in upper Lynn Canal near the city of Haines, supports one of the largest runs of sockeye salmon (Oncorhynchus nerka) in southeast Alaska. This stock is currently managed as a sustainable escapement goal range with a lower bound of 38,000 and an upper bound of 86,000 spawners. Escapement is monitored by the Alaska Department of Fish and Game with a weir on the Chilkoot River, and stock of origin from the District 15 commercial drift gillnet fishery harvest is determined using scale pattern analysis. We used Ricker spawner-recuit models in a Bayesian framework to fit data from brood years 1976-2010. Given significant autocorrelation at lag-1, we chose an autoregressive Ricker model for this assessment. Based on model results, maximum sustainable yield would be achieved with an escapement of approximately 52,900 sockeye salmon (median of spawning abundance at maximum sustained yield), and a range of 45,000-60,000 spawners would result in a greater than 80% probability of achieving at least 90% of maximum sustainable yield. This range of escapements fits within the current escapement goal range and, given considerable uncertainty in parameter estimates, we do not recommend changes to the goal at this time. However, some large escapements since 2012 will provide contrast to the existing data once the resulting recruits can be enumerated; thus, we recommend reassessing this escapement goal prior to the Alaska Board of Fisheries meeting in 2021.

Download or read book Sockeye Salmon Stock Status and Escapement Goals for Chilkoot Lake in Southeast Alaska written by Douglas Murrell Eggers and published by . This book was released on 2009 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hugh Smith Lake Sockeye Salmon Stock Assessment 2019 written by Malika T. Brunette and published by . This book was released on 2020 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2019, long-term population studies designed to evaluate adult sockeye salmon abundance and juvenile production at Hugh Smith Lake continued. An estimated 25,000 sockeye salmon smolt were counted through the smolt weir and an estimated 56% of smolt were freshwater-age-1 and 43% were freshwater-age-2. The escapement was counted through a weir, a mark-recapture study was conducted to confirm the weir count, and biological data were collected to estimate the age, length, and sex composition of the adult sockeye salmon escapement. The 2019 weir count of 2,241 adult sockeye salmon was below the optimal escapement goal range of 8,000-18,000 adult sockeye salmon and was the fourth lowest escapement since 1980. Age-1.3 adults were the most abundant adult age class, representing an estimated 82% of the total spawning population. Sockeye salmon spawn in 2 inlet streams, Buschmann Creek and Cobb Creek. Counts of live sockeye salmon in Buschmann Creek (not including mouth estimates) only exceeded 250 fish during peak spawn timing from 14 to 22 September (peak count 475 fish on 14 September). Counts of live sockeye salmon in Cobb Creek peaked at 56 fish on 15 September and all other counts were less than 25 fish. Reported subsistence harvest was 521 fish and accounted for an estimated 19% of the terminal run. The estimated minimum harvest rate in the District 101-108 commercial net fisheries was 77% in 2019.

Download or read book Escapement and Harvest of Chilkoot River Sockeye Salmon 2004 2006 written by Randall L. Bachman and published by . This book was released on 2013 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of a stock assessment program conducted by the Alaska Department of Fish and Game, Division of Commercial Fisheries to estimate escapements and harvest of adult Chilkoot Lake sockeye salmon (Oncorhynchus nerka) in 2004-2006.

Download or read book Escapement and Harvest of Chilkoot River Sockeye Salmon 2007 2012 written by Randall L. Bachman and published by . This book was released on 2014 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of a stock assessment program conducted by the Alaska Department of Fish and Game, Division of Commercial Fisheries to estimate escapements and harvest of adult Chilkoot Lake sockeye salmon (Oncorhynchus nerka) in 2007-2012.

Download or read book Eek Lake Sockeye Salmon Oncorhynchus Nerka Stock Assessment Project 2003 Final Report written by Jan Marie Conitz and published by . This book was released on 2005 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hugh Smith Lake Sockeye Salmon Stock Assessment 2017 2018 written by Malika T. Brunette and published by . This book was released on 2019 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2017 and 2018, long-term population studies designed to evaluate adult sockeye salmon abundance and juvenile production at Hugh Smith Lake continued. An estimated 80,000 sockeye salmon smolt were counted through the smolt weir in 2017, and 63,000 sockeye smolt were counted through the smolt weir in 2018. In 2017, an estimated 88% of smolt were freshwater age-1 and 12% were freshwater age-2. In 2018, an estimated 57% of smolt were freshwater age-1 and 42% were freshwater age-2. Biological data were collected to estimate the age, length, and sex composition of the adult sockeye salmon escapement, the escapement was counted through a weir, and a mark-recapture study was conducted to confirm the weir count. The 2017 weir count of 14,748 adult sockeye salmon fell within the optimal escapement goal range of 8,000-18,000 adult sockeye salmon. Conversely, the 2018 weir count of 2,039 adult sockeye salmon was the third lowest escapement since 1980 and well below goal. Age-1.3 adults were the most abundant adult age class to return in 2017, representing an estimated 78% of the total spawning population. Conversely, age-1.2 adults were the most abundant returning adult age class in 2018, representing an estimated 48% of the total spawning population. Numbers of fish observed spawning in Buschmann and Cobb creeks were extremely low during the normal peak spawn timing in 2018 due to extreme low water flow through most of September. Reported subsistence harvest in 2017 (617 fish) was the third largest harvest on record and the number of permit days fished was the highest on record. Conversely, reported subsistence harvest and participation dropped to very low levels in 2018 due to extremely low abundance. Estimated minimum harvest rates in the District 101-108 commercial net fisheries were 47% in 2017 and 66% in 2018.

Download or read book Stock Assessment Studies of Chilkat River Adult Sockeye and Chum Salmon Stocks in 2003 and 2004 written by Randall L. Bachman and published by . This book was released on 2010 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discusses the mark-recapture studies of adult Chilkat River sockeye (Oncorhynchus nerka) and chum (O. keta) salmon in 2003 and 2004 by the Alaska Department of Fish and Game and the Northern Southeastern Regional Aquaculture Association. These studies were done in order to estimate the escapement of chum and sockeye salmon in the Chilkat River, and sockeye salmon in Chilkat Lake, and to summarize age, sex, and length compositions for these populations.

Download or read book Hetta Lake Sockeye Salmon Oncorhynchus Nerka Stock Assessment Project 2003 Annual Report and 2001 2003 Final Report written by Margaret A. Cartwright and published by . This book was released on 2005 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stock Assessment of Salmon Lake Sockeye and Coho Salmon 2001 2003 written by Troy Allen Tydingco and published by . This book was released on 2006 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report discusses stock assessment of sockeye salmon, Oncorhynchus nerka, and coho salmon, O. kisutch, at Salmon Lake conducted between 2001 and 2003.

Download or read book Hugh Smith Lake Sockeye Salmon Stock Assessment 2020 written by Teresa M. Fish and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2020, long-term population studies designed to evaluate adult sockeye salmon (Oncorhynchus nerka) abundance and juvenile production at Hugh Smith Lake continued. The smolt weir count of 16,000 sockeye salmon smolt was tied for the 2nd lowest count on record. An estimated 48% of smolt were freshwater age-1 and 52% were freshwater age-2. The escapement was counted through a weir, a mark–recapture study was conducted to confirm the weir count, and biological data were collected to estimate the age, length, and sex composition of the adult sockeye salmon escapement. The 2020 weir count of 3,860 adult sockeye salmon was below the optimal escapement goal range of 8,000–18,000 adult sockeye salmon and was the 9th lowest escapement since 1980. Age-2.2 fish were the most abundant age class, representing an estimated 40% of the total spawning population. Counts of live sockeye salmon in Buschmann Creek (not including mouth estimates) only exceeded 250 fish during 4 of 18 surveys from 19 August to 7 November (peak count 556 fish on 27 October). Counts of live sockeye salmon in Cobb Creek peaked at only 27 fish on 30 September and all other counts there were less than 20 fish. Reported subsistence harvest was 70 fish and accounted for an estimated 2% of the terminal run. The estimated minimum harvest rate in the District 101–108 commercial net fisheries was 38% in 2020.