Download or read book Use of Air and Water Temperatures to Forecast Kvichak River Sockeye Salmon Returns from Smolt Migration Estimates written by Henry J. Yuen and published by . This book was released on 1984 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Birectilinear Recruitment Curves to Assess Influence of Lake Size on Survival of Sockeye Salmon written by Ralph Parks Silliman and published by . This book was released on 1970 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Informational Leaflet written by and published by . This book was released on 1983 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Synopsis and Critique of Forecasts of Sockeye Salmon Returning to Bristol Bay Alaska in 1990 written by Stephen M. Fried and published by . This book was released on 1990 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: The total number of sockeye salmon (Oncorhynchus nerka) forecasted to return to Bristol Bay in 1990 is 26,724,000 ( 80% confidence interval: 16,365,000 43,641,000). Runs are expected to exceed spawning escapement goals for all systems. Total projected sockeye salmon harvest is expected to be 15,989,000 (80% CI: 7,630,000 - 28,906,000). Most of this harvest will be taken within Bristol Bay inshore fishing districts (14,662,000), but some has been allocated to fisheries occurring in June in the vicinity of the Shumagin Islands and South Unimak under an existing management plan (8.3% of total Bristol Bay projected harvest: 1,327,000). The 1990 forecast was based on the ADF&G method which averaged results from three linear regression models based on the relationship between returns and either spawner, sibling, or smelt data. Based on the expected performance of several modifications of the ADF&G method, all available data was used to forecast 1990 runs to Nushagak and Togiak Districts, but data prior to the 1978 return year was omitted from calculations for Naknek-Kvichak, Egegik and Ugashik Districts. Al though out of range data were not used in calculations, their occurrence suggested that age-2.3 predictions for Kvichak, Egegik, and Ugashik Rivers could be too low. This could place the actual total return within the upper range of the 80% CI. The outlook for 1991-1993, based only on the spawner-recruit component of the ADF&G method, is for the total sockeye salmon run to Bristol Bay to be greatest in 1990 and least in 1991, mostly due to variations in the Kvichak River run. For all years examined, runs to all river systems are expected to exceed spawning goal requirements.
Download or read book Do Smolt Data Improve Adult Sockeye Salmon Forecasting Models in the Chignik Management Area written by Nyssa Baechler and published by . This book was released on 2018 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Preseason forecasts of adult returns for commercially-important Pacific salmon species provide initial guidance for fishery managers to meet escapement and harvest goals and serve to help the fishing industry plan appropriately for their fishing seasons. The goal of such forecasts is to reduce uncertainty in the management and harvesting processes, yet preseason forecasts often have limited predictive performance. This study compares predictive performance and forecast error of existing models – which use sibling relationships (returning adults of the same freshwater age and brood year) to forecast returns – to models with smolt and environmental predictor variables. I selected predictor variables related to the effects of smolt abundance, size, migration timing and water temperatures on subsequent adult returns and tested these in a nested set of model runs. In general, the simpler sibling models performed better in the most recent 5-year prediction periods than the more-complex smolt models. The two most common and consistent predictor variables across smolt models were the length of the smolt outmigration season (number of days between 5% and 95% total smolt run) and the temperature of the river at the date of 95% of the total smolt outmigration. This prompted me to create a class of hybrid sibling models using sibling predictor variables and the mid-June average river temperature. Results from all model classes suggest that the standard sibling forecast model remains the simplest and best predictive model to use in the Chignik Management Area. The relatively high performance of sibling-return models probably derives from the fact that the biological information captured implicitly in sibling relationships are redundant to the types of information smolt data reflect.
Download or read book Canadian Special Publication of Fisheries and Aquatic Sciences written by and published by . This book was released on 1987 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sockeye Salmon Oncorhynchus Nerka written by Canada. Department of Fisheries and Oceans and published by Fisheries and Oceans, Information and Publications Branch. This book was released on 1987 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt: A three-day symposium was organized by the Department of Fisheries and Oceans and convened at Nanaimo, British Columbia in November 1985. Advice on subject matter and participation came from an external committee of senior scientists and administrators in contributing agencies in Canada, Japan, the United States, and the Union of Soviet Socialist Republics. The papers included in the proceedings deal with sockeye biology and stock management. Papers on sockeye biology are divided into those concerned primarily with life history strategies and enhancement and development. Papers dealing with management are divided into the tools of management and management of some principal stocks.
Download or read book Forecasts of the 1999 Sockeye Salmon Runs to Bristol Bay Using Traditional FRI Methodology written by Donald E. Rogers and published by . This book was released on 1998 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Water Temperature Water Level and Adult Sockeye Salmon Migration Observations in Auke Creek Alaska written by H. W. Stiff and published by . This book was released on 2019 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inseason Forecasts of Sockeye Salmon Returns to the Bristol Bay Districts of Alaska written by Saang-Yoon Hyun and published by . This book was released on 2002 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Bristol Bay sockeye salmon fishery has been the most valuable salmon fishery in North America, and provides season employment for several thousand workers. The fishery consists of five reasonably discrete fishing districts corresponding to watersheds where the salmon are returning to spawn. The long term objective of management is to achieve Maximum Sustained Yield from the fishery, and this is implemented on an annual basis by regulating the time allowed for fishing to allow a predetermined number of fish to pass the fishery and make it to their natal streams and lakes to spawn. The expected total return of fish to each district is an important part of the fishery management and is equally important to the fishing fleet and the fish processors. I developed a statistical model for inseason run size prediction that uses data from (1) a test fishery at Pt. Moller, (2) the age composition of the catch at Pt. Moller, (3) the total return to date by district and (4) the age composition of the return to each district. Optimization and Bayesian methods are used to obtain both point estimates and distributions of estimates. I found that the temporal pattern in catches at Pt. Moller explained 59% of the variation in run timing in the fishing districts. Using the preseason forecast as a prior significantly improved the performance of the estimation during the initial stage of the season. This method provides a consistent way to incorporate diverse forms of data in a single unified statistical framework that should provide a significant improvement in inseason run forecasting. The method was tested using data from 1999 and found to perform well. In terms of the absolute values of relative errors of forecasts of the returns to the main districts (Kvichak-Naknek, Egegik, and Nushagak) made on June 24, June 29, and July 4, the mean values were 86.7%, 72.4%, and 59.9% when preseason forecasts were not incorporated, whereas they were 27.6%,25.4%, and 20.9% when preseason forecasts were incorporated.
Download or read book Supplement to the Pre season Return Forecasts for Fraser River Sockeye Salmon in 2015 written by and published by . This book was released on 2015 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt: To provide context for the 2015 forecast (DFO 2015), this year's Fraser Sockeye forecast supplement report focuses specifically on the 2011 brood year for lake-type stocks, and the 2011 and 2012 brood years for river-type stocks (i.e. Harrison Sockeye). This report synthesizes information on the adult migration conditions, escapement and spawner success, fry and their lake rearing conditions, smolt and juvenile migration, and ocean conditions. In addition, stock compositions of the 2011 escapements, 2013 downstream smolt migration, juvenile ocean migration, and 2015 return forecasts are compared to evaluate proportional changes in stock composition through time. The 2014 forecast supplement report (DFO 2014b) can be used, in combination with this report, to provide context for the five year olds returning in 2015 (DFO 2015).
Download or read book Temporal and Spatial Differences in Smolting Among Sockeye Salmon Oncorhynchus Nerka Populations Throughout Fresh and Seawater Migration and the Effect of Water Temperature on the Smolt Window written by Marley Carter Bassett and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Salmon smolts undergo physiological changes in the spring that are important for successful migration to seawater. Species that are widely distributed may differ in timing of physiological changes associated with smelting. In my first study, I compared indices of smolt characteristics among populations that differ in migration distance to the ocean. Fraser River sockeye salmon from four regions in the watershed were intercepted at different times during migration to characterize the parr-smolt transformation. Gill Na+/K+-ATPase (NKA) activity was highly variable at the start of migration, and was not explained by the distance from the ocean. Gill NKA activity changes with migration were also highly variable, but consistently smolts in the ocean had the highest gill NKA activities. The nature of smelting appears to be dynamic and variation was not based on the region of origin, timing during migration, or on the year of migration. The duration of time when anadromous salmon are able to survive in seawater - the smolt window - is influenced by temperature. In my second study, I found that warm water temperature abbreviated the smolt window. Additionally, isoforms of the gill NKA enzyme and endocrine signals suggest that the stimulus for smelting occurred prior emigration from the natal lake. Modeling the thermal experience that smolts encountered as they migrated downstream to the ocean in 2012 suggested Chilko fish did not experience temperatures as warm as the temperatures that abbreviated the smolt window in my study. Furthermore, climate change projections for temperature may not limit successful emigration of Chilko sockeye salmon smolts from central British Columbia to the ocean - but changes in other abiotic and biotic factors may confound this prediction.
Download or read book Regional and Climate driven Factors Affecting the Migrations of Sockeye Salmon Oncorhynchus Nerka Smolts in Alaska written by Christopher R. Dailey and published by . This book was released on 2020 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: The downstream migration of salmon smolts is triggered by a combination of responses to multiple environmental indicators, imposed on internal circannual rhythms, that result in variation between populations in timing. Using long-term data on daily smolt counts and associated environmental variables from multiple sources across Alaska, I tested the hypothesis that variation in migration timing between different sockeye salmon populations could be explained by differences in local environmental conditions. I first analyzed the peak, width, and interannual variation of the smolt migration period for eight populations from southwestern and southcentral Alaska. I then modeled the median emigration date and width of the emigration period as a function of stream temperature, air temperature, and precipitation to assess how each population responds to combinations of seasonal environmental cues that serve as indicators for the onset of downstream migration or conditions in the recipient environment (sea surface temperature). Lastly, I used the results of my analysis to identify spatial variation in the response of distinct salmon populations to environmental factors and identify trends in the migration timing of those populations. Through my analysis, I found that sea surface temperature and freshwater temperature are the primary environmental factors that control median smolt emigration date, while the width of the smolt emigration window is influenced primarily by freshwater temperatures and precipitation, with significant site-by-site variation.
Download or read book Climate Embryonic Development and Potential for Adaptation to Warming Water Temperatures by Bristol Bay Sockeye Salmon written by Morgan McKenzie Sparks and published by . This book was released on 2016 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rapidly warming water temperatures associated with climate change represent a substantial disturbance to the habitat of aquatic ectothermic organisms. For salmonid fishes (family Salmonidae), early life history survival and timing of reproduction and development are closely tied to temperature, such that altered thermal regimes could alter patterns of survival or shift phenology into a mismatch with the environment. Because temperature is the dominant driver of developmental rates, empirical statistical models have been developed to predict the timing of hatching and fry emergence based on incubation temperature. In this thesis I explored how the timing of hatching and emergence may shift in response to warming temperatures and how spawning timing across an Alaskan landscape is shaped by incubation temperatures experienced by sockeye salmon (Oncorhynchus nerka) embryos and alevin. Additionally, I quantified the relative roles of genetics and environmentally induced plasticity on the timing of hatching in two populations of sockeye salmon from the Iliamna Lake system, Alaska by rearing them in common garden conditions in the laboratory. To meet these goals I reformulated a widely cited developmental model to incorporate variability in natural regimes and use it to predict hatching timing over the course of the spawning duration for 25 populations of Bristol Bay sockeye salmon. Additionally, I hind- and forecasted lake temperature based off historical and predicted air temperatures to estimate and predict hatching for a single population. I found that predicted hatching timing for wild populations varied between 58 and 260 days, and was largely variable as a result of habitat thermal heterogeneity and parental spawn time. I also predicted a three-week decrease in hatching timing over the course of the next century for a single beach spawning population, which was just beyond historic variability. Counter to expectations, for a subset of populations hatching and emergence timing variability exceeded that of spawning timing, indicating the relationship between spawning timing and incubation temperature may be weaker than expected. The results of the common garden experiment revealed indistinguishable differences between populations in hatching timing across five temperature scenarios, but strong plasticity as timing differed between 74 and 189 days in the warmest to coolest treatment. Furthermore, I detected family-specific differences in hatching timing both within and among treatments consistent with heritable developmental rates and gene by environment interactions in days to hatch, where the interaction between treatment and family was as high as 10 days difference in hatching. Population or family-specific survival in this experiment did not differ in response to temperature suggesting a lack of thermal adaptation in this regard during this life stage in these populations. Alevin mass and length upon hatching varied little among treatments (
Download or read book Forecast of the 2000 Run of Sockeye Salmon to Bristol Bay written by and published by . This book was released on 1999 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The 2016 Chignik River Sockeye Salmon Smolt Outmigration written by Mary E. Loewen and published by . This book was released on 2017 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the results of the sockeye salmon Oncorhynchus nerka smolt monitoring and enumeration project conducted by the Alaska Department of Fish and Game in the Chignik River system in 2016. The research was designed to estimate population size and age structure of outmigrating smolt, assess fish body condition, collect samples for future genetic stock identification analysis, and provide data for the Chignik River preseason adult sockeye salmon forecast. The abundance of sockeye salmon smolt was estimated using a rotary-screw trap array and mark-recapture techniques. In 2016, 3.5 million sockeye salmon smolt were estimated to have outmigrated from April 21 to June 11. Of these, approximately 10,600 (0.3%) were freshwater-age-0; 1.33 million (37.5%) were freshwater-age-1; 2.19 million (62.1%) were freshwater-age-2; and approximately 1,800 (
Download or read book Time Series Analysis Forecasts for Sockeye Salmon Oncorhynchus Nerka in the Egegik Naknek and Kvichak Rivers of Bristol Bay Alaska written by Edward Vincent Farley (Jr.) and published by . This book was released on 1996 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
