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 Guide to Geography Programs in North America written by and published by . This book was released on 2003 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Conservation Status of Colorado River Cutthroat Trout written by and published by . This book was released on 1996 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Movement Distribution and Resource Use of Westslope Cutthroat Trout in the South Fork Clearwater River Basin written by Marika E. Dobos and published by . This book was released on 2015 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although many Westslope Cutthroat Trout Oncorhynchus clarki lewisi populations in Idaho are robust and stable, others are depressed. In some systems, such as the South Fork Clearwater River (SFCR) system, environmental conditions (e.g., summer temperatures) are hypothesized to limit populations of Westslope Cutthroat Trout. Radiotelemetry and snorkeling methods were used to describe movement, distribution, and habitat use of Westslope Cutthroat Trout in the SFCR in 2013 and 2014. Sixty-six tags were implanted into fish (155–405 mm). Sedentary and mobile summer movement patterns of Westslope Cutthroat Trout were observed. Sixty-two sites were snorkeled along the mainstem SFCR from 5–14 August 2014 to better describe the distribution of Westslope Cutthroat Trout. Twenty-three Westslope Cutthroat Trout were observed in 12 sites and at low density (mean ± SD; 0.0003 ± 0.0008 fish/m2 ). Results indicate that summer temperature was the primary factor limiting the distribution of Westslope Cutthroat Trout in the system.
Download or read book Genetic and Phenotype Phenotypic Catalog of Native Resident Trout of the Interior Columbia River Basin written by and published by . This book was released on 2001 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 1994 Fish and Wildlife Program of the Northwest Power Planning Council specifies the recovery and preservation of population health of native resident fishes of the Columbia River Basin. Among the native resident species of concern are interior rainbow trout of the Columbia River redband subspecies Oncorhynchus mykiss gairdneri 1 and westslope cutthroat trout O. clarki lewisi. The westslope cutthroat trout has been petitioned for listing under the U.S. Endangered Species Act (American Wildlands et al. 1997). Before at-risk populations can be protected, their presence and status must be established. Where introgression from introduced species is a concern, as in the case of both westslope cutthroat trout and redband rainbow trout, genetic issues must be addressed as well. As is true with native trout elsewhere in the western United States (Behnke 1992), most of the remaining pure populations of these species in the Columbia River Basin are in relatively remote headwater reaches. The objective of this project is to photo-document upper Columbia Basin native resident trout populations in Washington, and to ascertain their species or subspecies identity and relative genetic purity using a nonlethal DNA technique. FY-99 was year two of a five-year project in which we conducted field visits to remote locations to seek out and catalog these populations. In FY-99 we worked in collaboration with the Colville National Forest and Kalispel Indian Tribe to catalog populations in the northeastern corner of Washington State.
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 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 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 Movement and Population Structure of Westslope Cutthroat Trout Oncorhynchus Clarki Lewisi Inhabiting Headwaters Streams in Montana written by and published by . This book was released on 1998 with total page 42 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 Native Trout of Western North America written by Robert J. Behnke and published by . This book was released on 1992 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Understanding the Importance of Intermittently Fragmented Stream Habitat for Isolated Westslope Cutthroat Trout Oncorhynchus Clarki Lewisi in the Colville National Forest Washington written by and published by . This book was released on 2016 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate change and anthropogenic effects have vastly reduced Westslope Cutthroat Trout (Oncorhynchus clarki lewisi, WCT) habitat throughout their range, including the Colville National Forest in northeastern Washington where this study was conducted. Many native salmonid populations have declined in abundance since the early 1900s due to a variety of climate- and human-driven forces. Westslope Cutthroat Trout are especially sensitive to habitat loss or degradation and to climate change. Together, climate change, habitat degradation, and non-native salmonid invasions are contributing to increasingly fragmented WCT populations. Ongoing and predicted future warming trends are expected to further fragment these populations and isolate them in headwater stream reaches, with populations in the spatial margins of their distributions facing greater risk. Native salmonid populations are often separated or isolated by natural or artificial upstream migration barriers (i.e., waterfalls, culverts, etc.). Prior to continuing conservation and management actions targeting WCT, it is imperative to understand habitat requirements of this keystone species in fragmented areas. Field survey data were collected in the summer of 2015 on channel geomorphic characteristics and WCT presence/absence in 26 streams located in the Colville National Forest. A clear spatial separation was observed between Eastern Brook Trout (Salvenius fontinalis, EBT) and WCT above four culvert road crossings and the habitat in both of these areas was compared statistically to identify explicit differences. Logistic regression analysis indicated that the presence of isolated WCT populations was primarily positively associated with an increase in large wood and boulders, and negatively associated with increasing gravel, bedrock, habitat unit length, depth, and width. The final model correctly predicted 37.5% of isolated WCT presence observations and 96.5% of the WCT/EBT presence observations significantly better than by chance alone. This model, in fact, may be useful in identifying limited habitat due to the fragmented nature of the channel units supporting IWCT. Large wood and boulders were positively correlated to WCT presence, likely because both are important in the formation of pools and cascades. Channel unit length, width, depth, active channel width as well as gravel and bedrock substrates, were all negatively associated with WCT presence. This suggests that isolated WCT are primarily associated with small headwater cascades with complex shelter, which may provide greater thermal and predation refuge compared to shallow glide or large pool habitats. Overall, I concluded that differences in stream habitat above and below blocking culverts are not driving Westslope Cutthroat Trout distributions in the study area due to confounding factors such as the presence of problematic barriers and small sample size. I also conclude that future conservation and management decisions specific to WCT should prioritize complex cascade habitat in headwater stream reaches because of the type and quantity of habitat they may provide, especially during severe drought or low flow conditions.
Download or read book The Present Status and Distribution of the Westslope Cutthroat Trout Salmo Clarki Lewisi East and West of the Contenental Divide in Montana written by George A. Liknes and published by . This book was released on 1984 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exerpt From Abstract: "The distribution and abundance of westslope trout (Salmo clarki lewisi) has drastically declined over its historic range in the last 100 years. Although previous studies in Montana have identified strongholds, the status of westslope cutthroat statewide continued to be an uncertainty. The purpose of this report was to quantitatively determine the present and historic range as well as identify strongholds of genetically pure westlopw cutthroat in Montana... Statewide, 259 lakes contain or are believed to contain westslope cutthroat populations. Six percent are known to contain genetically pure populations. Fifteen of the 16 pure populations are found within Glacier National Park; the other population is located on the Flathead Indian Reservation. Only 4 lakes or reservoirs east of the continental divide were found to contain westslope populations."
Download or read book Habitat Suitability Information written by and published by . This book was released on 1984 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
