Download or read book Columbia River White Sturgeon Acipenser Transmontanus written by E. L. Brannon and published by . This book was released on 1986 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Columbia River White Sturgeon Acipenser Transmontanus Population Genetics and Early Life History Study written by and published by . This book was released on 1986 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Columbia River White Sturgeon Acipenser Transmontanus Population Genetics and Early Life History Study January 1 1986 to December 31 1986 Final Report written by and published by . This book was released on 1986 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 1986 Columbia River white sturgeon investigations continued to assess genetic variability of sturgeon populations isolated in various areas of the Columbia River, and to examine environmental factors in the habitat that may affect early life history success. Baseline data have been collected for three character sets. Twenty-eight loci have been analyzed for differences using electrophoresis, snout shapes were assessed for multivariate distinction, and scute counts have been examined as an index of variability. Fish that reside in the mid-Columbia and lower river have been sufficiently characterized by electrophoresis to compare with up-river areas. To date, few electrophoretic differences have been identified. However, Lake Roosevelt sturgeon sample size will be increased to determine if some of the observed differences from lower river fish are significant. Snout shape has been shown to be easily quantifiable using the digitizing technique. Scute count data initially indicate that variability exists within as well as between areas. Patterns of differentiation of one or more of these data sets may be used to formulate stock transplant guidelines essential for proper management or enhancement of this species. The historical habitat available to sturgeon in the Columbia River has changed through the development of hydroelectric projects. Dams have reduced the velocity and turbulence, and increased light penetration in the water column from less silt. These changes have affected the ability of sturgeon to feed and have made them more vulnerable to predation, which appear to have altered the ability of populations isolated in the reservoirs to sustain themselves. Present studies support the theory that both the biological and physical habitat characteristics of the Columbia River are responsible for reduced sturgeon survival, and justify consideration of enhancement initiatives above Bonneville to improve sturgeon reproductive success.
Download or read book Columbia River White Sturgeon Acipenser Transmontanus Early Life History and Genertics Study August 1 1984 to December 31 1985 Final Report written by and published by . This book was released on 1985 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research on Columbia River white sturgeon has been directed at their early life history as it may apply to production and enhancement strategies for management of the species. The river environment in which sturgeon historically migrated, spawned, and reared has changed through development. Habitat changes are expected to precipitate genetic changes in the fish, as well as reduce the fitness in populations. Genetic analysis of samples taken from various locations over the length of the Columbia River have indicated that observed gene frequencies in all areas sampled were not in Hardy-Weinburg equilibrium, which could suggest that the general population is experiencing perturbation in the system. Analysis thus far has exposed few differences between samples from the lower, middle, and upper portions of the system. Allelic differences were identified in fish from the Roosevelt Lake, which may be evidence of unique characteristics among fish from that general area.
Download or read book Columbia River White Sturgeon Acipenser Transmontanus Early Life History and Genetics Study written by E. L. Brannon and published by . This book was released on 1985 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Columbia River White Sturgeon Genetics and Early Life History written by E. L. Brannon and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Columbia River White Sturgeon Genetics and Early Life History written by and published by . This book was released on 1988 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: The geographic area of the genetics study broadly covered the distribution range of sturgeon in the Columbia from below Bonneville Dam at Ilwaco at Lake Roosevelt, the Upper Snake River, and the Kootenai River. The two remote river sections provided data important for enhancement considerations. There was little electrophoretic variation seen among individuals from the Kootenai River. Upper Snake river sturgeon showed a higher percentage of polymorphic loci than the Kootenai fish, but lower than the other areas in the Columbia River we sampled. Sample size was increased in both Lake Roosevelt and at Electrophoretic variation was specific to an individual sampling area in several cases and this shaped our conclusions. The 1987 early life history studies concentrated on the feeding behavior of juvenile sturgeon. The chemostimulant components in prey attractive to sturgeon were examined, and the sensory systems utilized by foraging sturgeon were determined under different environmental conditions. These results were discussed with regard to the environmental changes that have occurred in the Columbia River. Under present river conditions, the feeding mechanism of sturgeon is more restricted to certain prey types, and their feeding range may be limited. In these situations, enhancement measures cannot be undertaken without consideration given to the introduction of food resources that will be readily available under present conditions. 89 refs., 7 figs., 11 tabs.
Download or read book Swan Falls Instream Flow Study written by Donald R. Anglin and published by . This book was released on 1993 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Review of Fraser River White Sturgeon Acipenser Transmontanus written by James C. Echols and published by . This book was released on 1995 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recent Library Additions written by and published by . This book was released on 1990 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research and Development Report written by United States. Bonneville Power Administration and published by . This book was released on 1989 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1988 with total page 872 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Columbia River White Sturgeon Acipenser Transmontanus Enhancement May 1 December 31 1983 Final Report written by and published by . This book was released on 1984 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies were undertaken to examine and define the early life history characteristics of Columbia River white sturgeon as a working base from which enhancement measures could be developed. Adult sturgeon were captured and held for spawning at Covert's Landing, the site of the hatchery facilities below Bonneville Dam. Pituitary hormones stimulated ovulation; ripe females were live spawned surgically and the eggs incubated in hatching jars. Larvae were either reared at the hatchery site after incubation to advanced fingerling stages or transferred to the University laboratory for more detailed study. Displacement downstream occurs as a means of distribution and can last several days before a strong substrate preference is manifested. Once bottom contact is sought by the larvae, displacement is abated, and a general preference for sandy surface appears to predominate. Since potentially extensive displacement downstream could result in the distribution of larvae in saltwater, the tolerance of young sturgeon to saltwater was examined. The responsiveness of young sturgeon to artificial feed was positive. With these results, the original concern for identifying an adequate diet and food source that would be readily accepted by fry was greatly attenuated. The readiness of young fry to initiate feeding on the artificial diet made further study on feeding stimulants unnecessary. Examination of the feeding response suggested that as long as the diet used in the present study was initiated at the proper time and with adequate frequency, the fry would feed quite well and survive. 6 refs., 10 figs., 5 tabs.
Download or read book Research and Development Report Fiscal Years written by United States. Bonneville Power Administration and published by . This book was released on 1987 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Summary of Stock Identification Research on White Sturgeon of the Columbia River 1985 1991 Final Report written by and published by . This book was released on 1992 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: White sturgeon (Acipenser transmontanus) are a long-lived, primitive fish species which forage primarily along the river bottom of large river systems in the Pacific Northwest. Historically, as an anadromous species, they could distribute downstream to feed in the rich estuary or marine areas and then migrate back up the river to spawn. With the historic river becoming a series of flooded impoundments, sturgeon were denied open river access, but they appear to have been able to adapt to the altered environment. White sturgeon are found throughout the Columbia River and are thought to be successfully reproducing in some of the impoundments. In those reservoirs where little or no reproduction takes place, enhancement hatcheries may be an option for use in rebuilding isolated populations. However, the degree of stock specificity that exists in the Columbia River was unknown and precluded the use of the more abundant lower river fish as a common egg source to repropagate the upper river unless genetic similarity could be demonstrated among sturgeon throughout the river system. To resolve the issue, research was conducted to determine what level of genetic differentiation exists among sturgeon in the Columbia River system, using starch gel electrophoresis to enable a baseline of population genetic structure data to be assembled. A greater diversity in electrophoretic pattern was observed in the lower portions of the river. The bulk of the qualitative variability we noted was consistent throughout all sections of the river. Some specific quantitative differences were apparent between the areas we examined. Interpretation of the results was complicated by the fact that dam construction would tend to isolate and mix stocks by preventing the migration of fish returning upstream.
Download or read book Sport Fishery Abstracts written by and published by . This book was released on 1989 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Columbia River Basin Salmon Recovery Efforts written by United States. Congress. Senate. Committee on Appropriations. Subcommittee on Energy and Water Development and published by . This book was released on 1993 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:
