Download or read book Studies to Estimate Harvest Escapement Exploitation Rate Smolt Production and Marine Survival of Coho Salmon Stocks in the Situk Ahrnklin Lagoon 2004 2006 written by Leon D. Shaul and published by . This book was released on 2010 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discusses the results of a study the Alaska Department of Fish and Game conducted from 2004 to 2006 to estimate the fishery contribution, exploitation rate, smolt production and survival rate of coho salmon stocks in the Situk-Ahrnklin Lagoon near Yakutat, Alaska.
Download or read book Coho Salmon Smolt Production Adult Harvest and Escapement in Jordan and Duck Creeks Southeast Alaska 2005 2006 written by Carol L. Coyle and published by . This book was released on 2009 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to determine smolt production and estimate the marine survival, exploitation rates, and harvest of coho salmon, Oncorhynchus kisutch, in Jordan and Duck Creeks near Juneau, Alaska in 2005-2006.
Download or read book Coho Salmon Smolt Production Adult Harvest and Escapement from Jordan and Duck Creeks Southeast Alaska 2002 2003 written by Judith Lynn Lum and published by . This book was released on 2007 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to determine smolt production and estimate the marine survival, exploitation rates, and harvest of Jordan and Duck Creek coho salmon, Oncorhynchus kisutch.
Download or read book Coho Salmon Smolt Production Adult Harvest and Escapement from Jordan and Duck Creeks Southeast Alaska 2003 2005 written by Ryan Jordan Briscoe and published by . This book was released on 2008 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to determine smolt production and estimate the marine survival, exploitation rates, and harvest of Jordan and Duck Creek coho salmon, Oncorhynchus kisutch.
Download or read book Production of Coho Salmon from the 2005 Smolt Emigration from Chuck Creek in Southeast Alaska written by Steven J. McCurdy and published by . This book was released on 2008 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary purpose of this study was to estimate smolt production, marine survival, exploitation rates, and escapements of coho salmon, Oncorhynchus kisutch, from the 2005 smolt emigration from the Chuck Creek watershed in Southeast Alaska. Additional objectives were to determine if the date of smolt emigration influenced survival to maturity, and/or the date of return to freshwater (of jacks).
Download or read book Wild Salmon Production and Survival Evaluation written by and published by . This book was released on 2003 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Smolt Length and Emigration Timing on Marine Survival and Age at Maturity of Wild Coho Salmon Oncorhynchus Kisutch at Auke Creek Juneau Alaska written by Judith Lynn Lum and published by . This book was released on 2003 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Coho salmon Oncorhynchus kisutch smolt were collected during the 1993-1997 emigrations at Auke Creek near Juneau, Alaska. Each day emigrants were separated into four size categories: small 90 mm), medium (90 - 110 mm), large (111 - 125 mm), and extra large ( 125 mm), tagged with a sequentially coded-wire tag, and released at tidewater. Tags from returning adults and jacks were collected and decoded in 1993-1998. Most survivors originated from the large and extra large categories, 40.5% and 43.1%, respectively. Large smolts contributed 28.9% to smolt-to-jack returns, significantly less than the smolt-to-jack survival contributed by extra large smolts, 67.8%. Smolt year, emigration date, and smolt length were significant in determining the length of returning jacks. In the 1993 and 1997 smolt years, significantly smaller returning adults originated from smolts that migrated later. Larger smolts produced significantly larger returning adults in all smolt years except 1994"--Leaf iii.
Download or read book Marine Survival of Coho Salmon Oncorhynchus Kisutch from Small Coastal Watersheds in Northern California written by Sean M. Cochran and published by . This book was released on 2015 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: California coho salmon Oncorhynchus kisutch populations are at low abundance and factors governing recruitment variability remain unclear. Changes in freshwater habitat that increase juvenile growth and size of salmon outmigrating to sea (smolts) may improve ocean survival. The best data to evaluate this among wild coho salmon populations in California come from life-cycle monitoring (LCM) stations. This study investigated whether marine survival is size-dependent (larger individuals within a cohort have higher marine survival) and whether sites and years with higher growth have higher marine survival across five LCM locations. I tested for size-dependent survival using two techniques: comparing the size of outmigrating smolts and back-calculated smolt sizes from scales of adult fish that survived to return; and using information from fish that were tagged as smolts and survived to return as adults. Analyses comparing smolt sizes back-calculated from adult scales and observed lengths from smolt traps indicated that within-year size-dependent mortality at sea occurred among many outmigrant cohorts, while analyses using smolt lengths of recaptured adult fish tagged as juveniles did not indicate any within-cohort size-selective mortality at sea. Potential explanations for the conflicting results include errors in scale back-calculation; smolts growing in habitats below smolt traps prior to ocean entrance; and fish with alternative juvenile life histories that were unaccounted for in outmigrant sampling surviving and contributing to the adult populations. In regressions across sites and years, marine survival was positively associated with early marine growth measured from the scales of surviving adult salmon and in some instances marine survival was also positively associated with mean fork length of outmigrating smolts. Although size may be an important determinant of ocean survival, this study shows that comparison of back-calculated smolts sizes from scales of adult fish and observed lengths of smolts at an upstream trapping location are unreliable approaches for testing size-selective mortality. This study also provides support for expanding studies at LCM stations to determine how juvenile coho salmon use habitat downstream of migrant trapping locations.
Download or read book Variable Effects of Biological and Environmental Processes on Coho Salmon Marine Survival in Southeast Alaska written by Michael J. Malick and published by . This book was released on 2008 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: "I examined the relationships between coho salmon Oncorhynchus kisutch marine survival and seven biological and physical covariates across 14 Southeast Alaska (SEAK) stocks. A primary focus of the study was to investigate the influence of pink O. gorbuscha and chum O. keta salmon fry abundances on marine survival. The coho salmon stocks exhibited strong covariation, suggesting common regional processes are influencing marine survival in SEAK. However, only two of the covariates, the North Pacific index and SEAK pink salmon harvest, had consistent relationships across all 14 stocks with both of the covariates relating positively with marine survival. The other covariates all had inconsistent relationships with marine survival. An index representing hatchery pink and chum salmon fry abundance had a stronger estimated effect on marine survival than an index of wild pink salmon fry abundance and SEAK pink salmon harvest numbers. The magnitude and sign of the hatchery pink and chum salmon effect varied greatly among different localities. This study provides evidence that coho salmon stocks throughout SEAK experience some degree of regional concordance in the marine environment, but also that local stock specific conditions are important in fully understanding variation in marine survival"--Leaf iii.
Download or read book Coho Salmon Smolt Abundance Harvest and Escapement at Cottonwood Creek During 1999 2001 written by Thomas B. Namtvedt and published by . This book was released on 2017 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 1999 and 2000, a coded-wire-tagging (CWT) project was conducted on coho salmon (Oncorhynchus kisutch) smolt at Cottonwood Creek near Wasilla, Alaska. An estimated 63.6% and 77.5% of coho salmon smolt were counted, injected with CWTs, and marked by clipping the adipose fin in 1999 and 2000, respectively. Estimates of the total smolt outmigration at the Cottonwood Creek weir were 53,651 (SE 1,021) in 1999 and 51,254 (SE 462) in 2000. In 2000 and 2001, returning tagged adult coho salmon were recovered in gillnet fisheries and from sport anglers, and were censused at the Cottonwood Creek weir. Based on CWT recoveries in 2000, an estimated 643 (SE 61) Cottonwood Creek coho salmon were caught in the drift gillnet fishery, 34 (SE 10) in the Central District Eastside set gillnet fishery, 791 (SE 28) in the Northern District set gillnet fishery, and 282 (SE 143) by sport anglers. During 2001, an estimated 160 (SE 25) Cottonwood Creek coho salmon were caught in the drift gillnet fishery, 40 (SE 28) in the Central District Eastside set gillnet fishery, 608 (SE 22) in the Northern District set gillnet fishery, and 647 (SE 204) by sport anglers. The estimated Cottonwood Creek coho salmon adult returns were 3,646 (SE 158) and 4,980 (SE 209) for 2000 and 2001, respectively. In 2000, the estimated commercial and sport exploitation rates were 40.3% (SE 1.9%) and 7.7% (SE 3.6%), respectively. In 2001, these were 16.2% (SE 1.0%) and 13.0% (SE 3.6%), respectively. The estimated marine survival rate of emigrating coho salmon smolt was 6.8% (SE 0.3%) in 1999 and 9.7% (SE 0.4%) in 2000. CWT recovery data suggest that marine survival was positively related to smolt length and earlier emigration (tagging). Sockeye salmon (O. nerka) smolt and adults were also counted and sampled at the Cottonwood Creek weir.
Download or read book Smolt Abundance and Adult Escapement of Coho Salmon in the Taku River 2022 2024 written by Jeffrey T. Williams and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coho salmon Oncorhynchus kisutch smolt abundance and adult escapement will be estimated for the Taku stock of coho salmon originating from the Canadian portion of the Taku River, above the U.S./Canada border. This large glacial river flows into Taku Inlet about 30 km northeast of Juneau, Alaska. Multiple, independent sampling approaches will be used including coded-wire-tagging of smolt, adult harvest sampling, and an inriver adult mark–recapture experiment. A modified Petersen estimator will be used to estimate the smolt emigration during 2022–2024. A mark–recapture experiment will be used to estimate inriver runs of adult coho salmon in 2022–2024. Radio tags will be used to estimate the number of fish tagged during event 1 of the adult mark–recapture experiment that did not pass the U.S./Canada Border. Inriver harvest will be accounted for in determining escapement estimates for coho salmon annually. Scale samples of coho salmon will be used for age analysis to estimate annual age compositions. Coho salmon smolt will be systematically sampled to estimate the mean length for each species.
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.
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 A Mark recapture Experiment to Estimate the Escapement of Coho Salmon in the Situk River 2004 written by David L. Waltemyer and published by . This book was released on 2005 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Smolt Production and Harvest of Coho Salmon from the Situk River 1992 1993 written by Randolph P. Ericksen and published by . This book was released on 1997 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Charrs written by E.K. Balon and published by Springer. This book was released on 1980-04-30 with total page 948 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book North Pacific Temperate Rainforests written by Gordon H. Orians and published by University of Washington Press. This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The North Pacific temperate rainforest, stretching from southern Alaska to northern California, is the largest temperate rainforest on earth. This book provides a multidisciplinary overview of key issues important for the management and conservation of the northern portion of this rainforest, located in northern British Columbia and southeastern Alaska. This region encompasses thousands of islands and millions of acres of relatively pristine rainforest, providing an opportunity to compare the ecological functioning of a largely intact forest ecosystem with the highly modified ecosystems that typify most of the world's temperate zone. The book examines the basic processes that drive the dynamic behavior of such ecosystems and considers how managers can use that knowledge to sustainably manage the rainforest and balance ecosystem integrity with human use. Together, the contributors offer a broad understanding of the challenges and opportunities faced by scientists, managers, and conservationists in the northern portion of the North Pacific rainforest that will be of interest to conservation practitioners seeking to balance economic sustainability and biodiversity conservation across the globe. Gordon Orians is professor emeritus of biology at the University of Washington. John Schoen is a senior science advisor at Audubon Alaska. Other contributors include Paul Alaback, Bill Beese, Frances Biles, Todd Brinkman, Joe Cook, Lisa Crone, Dave D'Amore, Rick Edwards, Jerry Franklin, Ken Lertzman, Stephen MacDonald, Andy MacKinnon, Bruce Marcot, Joe Mehrkens, Eric Norberg, Gregory Nowacki, Dave Person, and Sari Saunders.
