Download or read book Hybridization Between Westslope Cutthroat Trout Oncorhynchus Clarki Lewisi and Rainbow Trout O Mykiss written by Nathaniel P. Hitt and published by . This book was released on 2002 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Management and Life History Consequences of Hybridization Between Westslope Cutthroat Trout oncorhynchus Clarkii Lewisi and Rainbow Trout oncorhynchus Mykiss written by Matthew Corsi and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The role of introductions of nonnative fishes in the decline of native fishes cannot be overstated. Westslope cutthroat trout (Oncorhynchus clarkii lewisi, WCT) are a salmonid native to the northern Rocky Mountains. These trout hybridize with rainbow trout (O. mykiss, RBT) where they are sympatric; however, in portions of the WCT range where RBT have been introduced, hybridization appears to spread rapidly and threatens continued existence of WCT. The conservation value of these hybridized populations is equivocal, and a better knowledge of the ecological, demographic, behavioral, and genetic consequences of hybridization is needed to better inform conservation strategies. I investigated three related questions: specifically, what landscape factors are associated with estimates of introgression; what are life history differences between WCT and hybrids; and what are tradeoffs in restoring migratory life history in populations threatened by hybridization? The riverscape context plays a substantial role in the distribution of hybrids, as estimates of introgression declined with increases in stream slope, elevation, and distance from a primary source of RBT, three correlated landscape variables. Spatial variation in patterns of hybridization suggests clarifying objectives for sampling and careful designs are necessary to adequately understand the status of populations. Variation in location may relate to some of the ecological differences, such as growth, among fish with different levels of introgression. In the Jocko River, hybrids with ancestry> 20% RBT demonstrated higher growth, earlier migration, increased egg size, and lower fecundity versus WCT. These lines of evidence demonstrate the importance of limiting further hybridization even in populations that already have low levels of hybridization. Given that many unaltered populations currently reside in isolated habitat fragments, I evaluated several demographic tradeoffs of restoring a migratory life history weighed against the risks of increased potential for hybridization from removing barriers or selectively passing migratory fish above the barriers using both matrix and genetic population models. Restoration of migratory life history substantially increases population viability; however, hybridization in above-barrier population increases predictably relative to hybridization status of below-barrier population, which may reduce viability if vital rates are reduced in hybrids. Hybridization creates a challenging set of management problems, but this research adds several important pieces to the puzzles to help develop and evaluate conservation strategies.
Download or read book Naturally Occurring Hybridization and Introgression Between Westslope Cutthroat Oncorhynchus Clarki Lewisi and Native Rainbow Trout Oncorhynchus Mykiss Within Three Tributaries of the Middle Fork Salmon River Idaho written by Michael Patrick Peterson and published by . This book was released on 2004 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Ecological Consequences of Hybridization Between Native Westslope Cutthroat Trout Oncorhynchus Clarkii Lewisi and Introduced Rainbow Trout O Mykiss in South Western Alberta written by Michael D. Robinson and published by . This book was released on 2007 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rainbow Trout Oncorhynchus Mykiss Invasion and the Spread of Hybridization with Native Westslope Cutthroat Trout Oncorhynchus Clarkii Lewisi written by Matthew C. Boyer and published by . This book was released on 2008 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: We analyzed 13 microsatellite loci to estimate gene flow among westslope cutthroat trout, Oncorhynchus clarkii lewisi, populations and determine the invasion pattern of hybrids between native O. c. lewisi and introduced rainbow trout, Oncorhynchus mykiss, in streams of the upper Flathead River system, Montana (USA) and British Columbia (Canada). Fourteen of 31 sites lacked evidence of O. mykiss introgression, and gene flow among these nonhybridized O. c. lewisi populations was low, as indicated by significant allele frequency divergence among populations (?ST = 0.076, ?ST = 0.094, P
Download or read book Behavioral Ecological and Fitness Consequences of Hybridization Between Native Westslope Cutthroat Trout Oncorhynchus Clarkii Lewisi and Nonnative Rainbow Trout O Mykiss written by Clint Cain Muhlfeld and published by . This book was released on 2008 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anthropogenic hybridization is one of the greatest threats to global biodiversity. Hybridization and introgression may lead to a loss of locally adapted gene complexes and ecological adaptations in native populations, yet these potential consequences have not been fully evaluated in nature. I investigated factors influencing the spread of hybridization between native westslope cutthroat trout (Oncorhynchus clarkii lewisi) and nonnative rainbow trout (O. mykiss) in the upper Flathead River system, Montana (USA) and British Columbia (Canada). The fundamental questions of my dissertation were: what are the behavioral, ecological, and fitness consequences of hybridization and what factors influence successful invasion of hybrids? First, I assessed the patterns of spawning between parental species and their hybrids and found that hybridization alters the spawning behavior of migratory westslope cutthroat trout, and is spreading via long distance dispersal of hybrids from downstream sources and some temporal overlap during spawning. Second, I describe for the first time how a wide range of levels of nonnative admixture affect fitness of cutthroat trout in the wild by estimating reproductive success in a recently invaded stream using parentage analysis with multilocus microsatellite markers. Small amounts of hybridization markedly reduced reproductive success, with fitness exponentially declining by ~50% with 20% nonnative genetic admixture. Finally, I evaluated the association of local-habitat features, landscape characteristics, and biotic factors with the spread of hybridization in the system, and found that hybridization increases in streams with warmer water temperatures, high land use disturbance and close proximity to the source of hybridization; however, none of these factors appeared sufficient to prevent further spread. These combined results suggest that hybrids are not only genetically different than westslope cutthroat trout but also have reduced fitness and are ecologically different, and that hybridization is likely to continue to spread if hybrid populations with high amounts of rainbow trout admixture are not reduced or eliminated. I conclude that extant aboriginal cutthroat trout are at greater conservation risk due to hybridization than previously thought and policies that protect hybridized populations need reconsideration.
Download or read book Cold Tolerance Performance of Westslope Cutthroat Trout Oncorhynchus Clarkii Lewisi and Rainbow Trout Oncorhynchus Mykiss and Its Potential Role in Influencing Interspecific Hybridization written by M. M. Yau and published by . This book was released on 2014 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hybridization between rainbow trout (Oncorhynchus mykiss (Walbaum, 1792)) and westslope cutthroat trout (Oncorhynchus clarkii lewisi (Girard, 1856)) occurs commonly when rainbow trout are introduced into the range of westslope cutthroat trout. Typically, hybridization is most common in warmer, lower elevation habitats, but much less common in colder, higher elevation habitats. We assessed the tolerance to cold water temperature (i.e., critical thermal minimum, CTMin) in juvenile rainbow trout and westslope cutthroat trout to test the hypothesis that westslope cutthroat trout better tolerate low water temperature, which may explain the lower prevalence of rainbow trout and interspecific hybrids in higher elevation, cold-water habitats (i.e., the ?elevation refuge hypothesis?). All fish had significantly lower CTMin values (i.e., were better able to tolerate low temperatures) when they were acclimated to 15 °C (mean CTMin = 1.37 °C) versus 18 °C (mean CTMin = 1.91 °C; p
Download or read book Rainbow Trout Invasion and the Spread of Hybridization with Native Westslope Cutthroat Trout written by Matthew C. Boyer and published by . This book was released on 2006 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geographic Patterns of Introgressive Hybridization Between Native Yellowstone Cutthroat Trout Oncorhynchus Clarki Bouvieri and Introduced Rainbow Trout Oncorhynchus Mykiss written by Kelly Gunnell and published by . This book was released on 2006 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Species Distribution of Coexisting Westslope Cutthroat Trout Oncorhynchus Clarki Lewisi and Rainbow Trout Oncorhynchus Mykiss Within the Little Naches Watershed of Eastern Washington written by Amy Kurant Matthews and published by . This book was released on 2001 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Molecular Study of Possible Introgressive Hybridization Between Westslope Cutthroat Trout and Rainbow Trout written by William James Blackhall and published by . This book was released on 1994 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Natural Hybridization Between Coastal Cutthroat Trout Oncorhynchus Clarki and Steelhead Trout Oncorhynchus Mykiss Within Redwood Creek California written by W. George Neillands and published by . This book was released on 1990 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Molecular Investigation of Hybridization Between Natural Populations of Coastal Rainbow Trout Oncorhynchus Mykiss Irideus and Coastal Cutthroat Trout O Clarki Clarki in the Copper River Delta Alaska written by Ian Williams and published by . This book was released on 2004 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Natural Hybridization Between Coastal Cutthroat Trout Oncorhynchus Clarki Clarki and Steelhead Trout Oncorhynchus Mykiss Within Redwood Creek California written by W. George Neillands and published by . This book was released on 2001 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Diagnostic Single Nucleotide Polymorphisms for Identifying Westslope Cutthroat Trout Oncorhynchus Clarki Lewisi Yellowstone Cutthroat Trout Oncorhynchus Clarkii Bouvieri and Rainbow Trout Oncorhynchus Mykiss written by Steven T. Kalinowski and published by . This book was released on 2010 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We describe 12 diagnostic single nucleotide polymorphism (SNP) assays for use in species identification among rainbow and cutthroat trout: five of these loci have alleles unique to rainbow trout (Oncorhynchus mykiss), three unique to westslope cutthroat trout (O. clarkii lewisi) and four unique to Yellowstone cutthroat trout (O. clarkii bouvieri). These diagnostic assays were identified using a total of 489 individuals from 26 populations and five fish hatchery strains.
Download or read book Origin and Extent of Rainbow Trout Hybridization and Introgression of Westslope Cutthroat Trout Populations in the Pend Oreille Drainage Idaho written by Matthew Richard Campbell and published by . This book was released on 2013 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cutthroat written by Pat Trotter and published by Univ of California Press. This book was released on 2008 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cutthroat tells the full story of the genuine native trout of the American West. This new edition, thoroughly revised and updated after 20 years, synthesizes what is currently known about one of our most interesting and colorful fishes, includes much new information on its biology and ecology, asks how it has fared in the last century, and looks toward its future. In a passionate and accessibly written narrative, Patrick Trotter, fly fisher, environmental advocate, and science consultant, details the evolution, natural history, and conservation of each of the cutthroat's races and incorporates more personal reflections on the ecology and environmental history of the West's river ecosystems. The bibliography now includes what may be the most comprehensive and complete set of references available anywhere on the cutthroat trout. Written for anglers, nature lovers, environmentalists, and students, and featuring vibrant original illustrations by Joseph Tomelleri, this is an essential reference for anyone who wants to learn more about this remarkable, beautiful, and fragile western native.
