Download or read book Assessing the Production of Sockeye Salmon Oncorhynchus Nerka at Chilkat Lake Southeast Alaska Using Current Trophic Conditions and the Paleolimnologic Sediment Record written by David Barto and published by . This book was released on 2004 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Anadromous sockeye salmon are the only Pacific salmon that require an extensive rearing period in a lake environment. Recent studies suggest changes in lake nutrient inputs are directly related to the magnitude of annual spawning populations (escapement), and can be quantified by sediment stable isotope analysis of nitrogen 15N). Marine nitrogen supplied by returned salmon is enriched in 15N relative to the freshwater nitrogen, which is derived from atmospheric N2 (ð15N=0 0/00). Recent (1987-1996) limnological investigations of Chilkat Lake, Alaska, matched to brood year escapement estimates, indicate that sockeye marine-derived phosphorus and nitrogen contributed up to 87% and 20%, respectively, of the lake nutrient pool. Since salmon populations fluctuate annually, the resulting marine derived nutrient (MDN) inputs and ð15N also fluctuate. Sedimentary ð15N is positively correlated (r2=0.8605, p=0.0076, df=5) with observed escapement. Additionally, ð15N is positively related to lake paleoproductivity and inversely correlated with high concentrations of CaCO3 and glacial silt. The frequency and duration of these CaCO3 inputs are believed to be the result of climate related glacial meltwater intrusions from the Tsirku River. Thus, fluctuations in MDN can be shown to influence the overall sockeye salmon production at Chilkat Lake by controlling lake productivity"--Leaf iii.
Download or read book Growth of Juvenile Chilkat Lake Sockeye Salmon in Response to Density dependent and Environmental Factors written by Jodi Neil (C.) and published by . This book was released on 2018 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chilkat Lake, in northern Southeast Alaska, is home to a Sockeye Salmon Oncorhynchus nerka population that is an important component in local commercial, sport, and subsistence fisheries, and has been monitored since the late 1960s. The population began declining in the late 1980s, prompting fishery managers to evaluate the production potential of Chilkat Lake to determine if it could be a candidate for enhancement efforts such as fry stocking or lake fertilization. Sockeye Salmon fry were stocked into Chilkat Lake intermittently from 1989 to 2004 in both small- (
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 Assessing Juvenile Sockeye Salmon Oncorhynchus Nerka Energy Densities and Their Habitat Quality in the Chignik Watershed Alaska written by Heather Finkle and published by . This book was released on 2004 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Chignik watershed, on the southern side of the Alaska Peninsula, supports a large salmon fishery vital to the local economy. Recent morphological changes to the watershed generated concern regarding the sockeye salmon (Oncorhynchus nerka) stock that rears in Black Lake, at the head of the system. Studies of the Chignik watershed to date have not incorporated energy density data to explain the life history strategies of Chignik sockeye salmon. Re-estimated condition factor parameters improved our understanding of the length-weight relationships to fish health that isometric models described in Chignik sockeye salmon. Subsequent comparisons of age, length, weight, location, and temperature data to energy density indicated that Black Lake fish, which were all age 0 fish, were significantly affected by temperature and had energy densities greater than did fish from other areas of the watershed. Sockeye salmon captured in Chignik Lake, Chignik River, and Chignik Lagoon were only energetically different from one another based on age. Observed seasonal trends suggested juvenile sockeye salmon emigrate from Black Lake before the onset of winter due to forage and temperature limitations. A constant downstream migration occurred in the watershed during the summer, which suggested smoltification and osmoregulation processes in Chignik Lagoon fish"--Leaf iii.
Download or read book History of the Fishery and Summary Statistics of the Sockeye Salmon Oncorhynchus Nerka Runs to the Chignik Lakes Alaska 1888 1966 written by Michael L. Dahlberg and published by . This book was released on 1979 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Production Potential of Sockeye Salmon Nursery Lakes in Southern Southeast Alaska written by T. P. Zadina and published by . This book was released on 1995 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Potential sockeye Oncorhynchus nerka salmon production for 112 anadromous lake systems in southern Southeast Alaska were calculated using an euphotic volume model"--Page vi.
Download or read book Limnological and Fisheries Assessment of Sockeye Salmon Oncorhynchus Nerka Production in Afognak Lake written by Lorne E. White and published by . This book was released on 1990 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Limnological and Fisheries Assessment of the Potential Production of Sockeye Salmon Oncorhynchus Nerka in Spiridon Lake written by Gary B. Kyle and published by . This book was released on 1990 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An In season Management System for Sockeye Salmon Returns to Lynn Canal Southeast Alaska written by Scott Alan McPherson and published by . This book was released on 1990 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: Master thesis aimed at providing an information system to the managers of the Lynn Canal (southeastern Alaska) sockeye salmon (Oncorhynchus nerka) resource which will provide the tools to harvest the optimal annual harvest in numbers of fish.
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 Factors Influencing Production of Sockeye Salmon Oncorhynchus Nerka in Lakes of Southwestern Alaska written by Robert Louis Burgner and published by . This book was released on 1964 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessment of Factors Affecting Sockeye Salmon Oncorhynchus Nerka Production in Ozette Lake WA written by John Paul Blum and published by . This book was released on 1988 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sockeye Salmon Oncorhynchus Nerka Stock Assessment and Evaluation in Southeastern Alaska 1982 1983 written by Fred Bergander and published by . This book was released on 1985 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Assessment of the Juvenile Sockeye Salmon Oncorhynchus Nerka Populations of Babine Lake written by Jeremy M. B. Hume and published by Cultus Lake, B.C. : Fisheries and Oceans Canada, Science. This book was released on 2000 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Juvenile sockeye salmon rearing in Babine Lake were re-examined 22 years after the initiation of the Babine Lake Development Project (BLDP). Abundance, distribution, size, and species composition of the limnetic fish populations, including juvenile sockeye salmon, were determined by hydroacoustic and midwater trawl surveys in the autumn of 1993 and the summer and fall of 1994 and 1995 and compared to results collected before and shortly after the start of the BDLP. Our objectives were to look for: 1) changes in the abundance of juvenile sockeye relative to spawning numbers; 2) changes in the utilization of the available nursery area; and 3) the effects of increased popualtion size and density on the size and growth of juvenile sockeye.
Download or read book Limnological and Fisheries Evidence for Rearing Limitation of Sockeye Salmon Oncorhynchus Nerka Production from Packers Lake Cook Inlet Alaska 1973 1983 written by Jeffery P. Koenings and published by . This book was released on 1985 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Factors Influencing Zooplankton Populations in Alaskan Sockeye Salmon Oncorhynchus Nerka Nursery Lakes written by Jon Nicholas Sweetman and published by . This book was released on 2001 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The relative importance of sockeye salmon, invertebrate predators, and other environmental factors in structuring the size and abundance of zooplankton populations was examined in a series of 23 lakes from southern Alaska. Zooplankton abundance was strongly related to sockeye density, along with nutrient availability and alkalinity. The mean size of Bosmina longirostris, the dominant herbivorous cladoceran, was positively correlated with the abundance of the predatory copepod, Cyclops columbianus. Changes in the size and abundance of Bosmina remains over the past 300-500 years were then determined for sediments from two lakes on Kodiak Island, Alaska. The zooplankton communities showed varying responses to past changes in salmon populations, resulting from relative changes in the magnitude of adult salmon-derived nutrient loading and in predation pressure from juvenile sockeye and cyclopoid copepods. Knowledge of how various factors impact zooplankton can have important implications for the effective management of sockeye within these lake systems"--Leaf 3.
Download or read book Assessment of Lacustrine Productivity Relative to Juvenile Sockeye Salmon Oncorhynchus Nerka Production in Chignik and Black Lakes written by Gary B. Kyle and published by . This book was released on 1992 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reports on the results of limnological investigations of general water-quality parameters, nutrients, phytoplankton, zooplankton, and fall fry, which were conducted in Chignik and Black Lakes during 1991 to characterize lake productivity relative to juvenile sockeye salmon (Oncorhynchus nerka) production, historical information, and other sockeye nursery lakes.
