Download or read book Information in Support of a Recovery Potential Assessment of Rainbow Trout Oncorhynchus Mykiss Athabasca River Populations written by C. D Sawatzky and published by . This book was released on 2018 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recovery Potential Modelling of Rainbow Trout Oncorhynchus Mykiss Athabasca River Populations written by Amanda L. Caskenette and published by . This book was released on 2018 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has assessed the Athabasca River populations of Rainbow Trout (Oncorhynchus mykiss) as Endangered in Canada. Here we present population modelling in support of the recovery potential assessment of the species. Results include a sensitivity analysis, determination of allowable harm, and minimum viable population estimates to inform recovery targets for population abundance and required habitat"--Abstract, p. iv.
Download or read book Proceedings of the Regional Recovery Potential Assessment RPA of Rainbow Trout Oncorhynchus Mykiss Athabasca River Populations written by and published by . This book was released on 2018 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recovery Potential Modelling of Rainbow Trout Oncoryhyncus Mykiss Athabasca River Populations written by Amanda L Caskenette and published by . This book was released on 2018 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book COSEWIC Assessment and Status Report on the Rainbow Trout Oncorhynchus Mykiss in Canada written by and published by . This book was released on 2014 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recovery Strategy for the Rainbow Trout Oncorhynchus Mykiss in Canada Athabasca River Populations written by and published by . This book was released on 2020 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact of Triploid Rainbow Trout and Naturalized Rainbow Trout Oncorhynchus Mykiss on Recovery of Lahontan Cutthroat Trout Oncorhynchus Clarkii Henshawi in the Truckee River Watershed written by Veronica Kirchoff and published by . This book was released on 2016 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt: Historically the Lahontan cutthroat trout (Oncorhynchus clarkii henshawi, LCT) occurred throughout the Truckee River basin, supporting important commercial fisheries and was extirpated in the 1940s due to water diversions, predation, competition and hybridization with non-native trout. To provide angling opportunities, Rainbow trout (Oncorhynchus mykiss, RBT) has been planted, and there is a robust naturalized population throughout the Truckee River. Recovery efforts are underway to reintroduce the threatened LCT back into their native habitat in the Truckee; however, planting LCT sympatric with naturalized RBT can support hybridization between the species and hamper LCT recovery. Since 2004, in an effort to limit hybridization, 90% of the RBT stocked are non-reproductive triploid RBT. Over 3,400 trout samples were collected in the Truckee River and its tributaries from 2007-2010. These trout were identified as pure LCT, pure RBT, LCT/RBT hybrids or triploid RBT using bi-parentally inherited markers that differentiate between RBT and LCT and microsatellite markers that revealed triploidy in a proportion of the RBT. A mitochondrial marker was sequenced in hybrids to determine the maternal contribution to hybridization and to look at spawning success. The highest level of hybridization was found in 2008 from samples in the river tributaries. This correlates to the time period when fry stocked in 2005 and 2006 would reach sexual maturity. Backcrossing of hybrids with RBT was detected, and a low level of introgression indicates that hybridization has been occurring in the river for multiple generations. Mitochondrial sequences show that LCT is successfully competing for spawning gravels; however continued stocking of LCT without the removal of the naturalized RBT will likely lead to a hybrid swarm. Triploidy was successfully identified in the hatchery supplied known triploids; despite high levels of stocking of trpRBT, less than 10% of the RBT sampled in the Truckee River were identified as triploid. The diploid RBT samples represent the naturalized RBT population in the river. The genetic population structure of the naturalized RBT was investigated using 11 microsatellite loci to look for potential RBT eradication units allowing for LCT reintroduction. Barriers along the Truckee River contribute to developing population structure, but these barriers are transient, and structure varies year to year. No clear eradication units or regions of the river to potentially isolate a translocated LCT population from RBT encroachment were identified. Six of the 11 microsatellites cross amplified and showed variation in LCT. Comparison of the LCT and HYB sampled in the Truckee River to the LCT strains stocked indicates that the Pilot Peak Strain of LCT has a higher survivorship in the Truckee River compared to the contemporary Pyramid Lake or Independence Lake strains. Reintroduction of LCT into the Truckee River is possible, but would require the eradication of the reproductive RBT and extensive monitoring to detect hybridization.
Download or read book Recovery Potential Assessment for Chilcotin River and Thompson River Steelhead Trout Oncorhynchus Mykiss Designatable Units written by and published by . This book was released on 2018 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This Recovery Potential Assessment (RPA) focuses on the Chilcotin and Thompson River Designatable Units (DU) of steelhead trout. Both of these DUs were assessed as Endangered by COSEWIC in an emergency assessment in January 2018"--Summary, p. 2.
Download or read book Information in Support of a Recovery Potential Assessment of Bull Trout Salvelinus Confluentus Saskatchewan Nelson Rivers Populations in Alberta written by C. D Sawatzky and published by . This book was released on 2016 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Habitat Suitability and Availability for Rainbow Trout Oncorhynchus Mykiss in the Canyon Reservoir Tailrace and Evaluation of Side Scan Sonar for Habitat Mapping in a Semi wadable River written by Greg A. Cummings and published by . This book was released on 2015 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rainbow Trout Oncorhynchus mykiss are typically stocked in tailraces across the southeastern United States to mitigate fish habitat and assemblage alterations caused by large impoundments. Hypolimnetic discharges from Canyon Reservoir have created conditions suitable for a coldwater tail race fishery and trout have been stocked there since 1966. Changes in habitat availability for adult Rainbow Trout with discharge rate were examined to provide flow and habitat improvement recommendations for the Canyon Reservoir tailrace. Physical habitat modeling incorporated habitat suitability information for trout coupled with hydraulic modeling to assess habitat quality and quantity at various flow rates. Habitat mapping included traditional surveying, remote sensing, bathymetric mapping, and side scan sonar. Side scan sonar was evaluated for efficiency and applicability to river systems similar to the tailrace. Results indicate that summer water temperature is likely the primary limiting factor for adult trout survival and could impose limitations on physical habitat during critical summer months. Modified flow rates and habitat improvement could cause a potential increase in adult trout abundance and assist put-grow-and-take strategies in the upper portion of the tailrace. Side scan sonar provided efficient mapping of non-wadable sections of the study area. Challenges related to water level, access, navigability, positional accuracy, and post-processing were overcome. Trial runs, training, map accuracy assessments, and technological development will improve the effectiveness of this technique.
Download or read book Recovery Implementation Program for Endangered Fish Species in the Upper Colorado River Basin written by U.S. Fish and Wildlife Service. Region 6 and published by . This book was released on 1987 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stock Assessment of Rainbow Trout in the Upper Kenai River Alaska 2018 written by Anthony Alexander Eskelin and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A multiple-event mark–recapture study was conducted on rainbow trout (Oncorhynchus mykiss) in the upper Kenai River in 2018. The objectives of this study were to estimate the abundance and fork length (FL) composition of rainbow trout in the most heavily fished section of the upper Kenai River (river miles 69.6–73.2) and to compare these estimates to those from previous surveys conducted in 1986, 1987, 1995, 2001, and 2009 on the same stretch of river. There were an estimated 10,568 (SE 608) rainbow trout at least 200 mm FL and 8,482 (SE 495) rainbow trout at least 300 mm FL in the study area. Abundance of fish at least 200 mm FL was 79% higher than in 2009 and 24% higher than in 2001. Abundance of fish at least 300 mm FL was 66% higher than in 2009, 33% higher than in 2001, and 52% higher than in 1995. Most of the rainbow trout were between 250 mm and 449 mm FL, accounting for 88% of the population. Approximately 75% of the population was less than 400 mm FL, which is the approximate upper length (16 inches total length) of fish allowed to be harvested by regulation. Overall, rainbow trout abundance in 2018 was considerably higher than in any other study year, but the number of fish more than 450 mm FL was only 743 (SE 71), which was less than half of what was observed in 1995, 2001, and 2009.
Download or read book Information Relevant to a Recovery Potential Assessment of Pure Native Westslope Cutthroat Trout Alberta Population written by Holly Cleator and published by . This book was released on 2009 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessing the Status of Rainbow Trout Oncorhynchus Mykiss Exposed to Sublethal Concentrations of Metals Using Bioindicators of Exposure and Immune System Function written by Gail Marie Dethloff and published by . This book was released on 1998 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stock Assessment of Rainbow Trout in the Wood River Lakes System 2003 2005 written by Jason E. Dye and published by . This book was released on 2008 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reports on the mark-recapture study of rainbow trout, Oncorhynchus mykiss, in the Wood River Lakes. The objectives of the study were to estimate the abundance and length composition of rainbow trout in this system.
Download or read book Assessment of Tributary Potential for Wild Rainbow Trout Recruitment in Hebgen Reservoir Montana written by Darin Allen Watschke and published by . This book was released on 2006 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Trout fisheries in Montana reservoirs are almost entirely maintained by stocking hatchery fish. An exception is Hebgen Reservoir, where wild rainbow trout Oncorhynchus mykiss were established in 1979. Continued, unexpectedly low gill net catch rates of rainbow trout led to the objective of this study, which was to assess tributary production of wild rainbow trout and identify potential limiting factors. A combination of redd surveys, adult, young-of-the-year (YOY; age-0), and juvenile (age- 1 and age-2) trapping, and measurements of water temperature and spawning and rearing habitat was used to assess spawning use and habitat characteristics of 11 tributaries, comprising 170 stream kilometers, in 2002 and 2003. A total of 5,642 redds were counted, suggesting the number of spawners was not limiting. Redd occurrence within individual habitat units was positively associated with spawning gravel densities, and negatively associated with rearing habitat density. At the tributary scale, redd abundance was positively associated with availability of both spawning and rearing habitat. Temperature also appeared to influence spawning as most production occurred in tributaries with May to July temperature averaging 8 to 10 .C. The majority (80%) of spawning occurred in only two of the 11 tributaries (Duck Creek and the South Fork of the Madison River). These tributaries contained a combination of abundant spawning and rearing habitat. Rainbow trout YOY production estimates exceeded 4.7 million in 2002 and 2003 combined and abundant YOY and age-1 and age-2 juvenile rainbow trout were captured during spring and summer outmigrations in two lake tributaries. Estimates of available spawning (7.0 ha) and rearing habitat (1.1 x 106 m3) suggest that tributary habitat does not limit the rainbow trout population of Hebgen Reservoir from reaching a self-sustaining level that would meet the recreational requirements of the sport fishery. However, high densities of YOY and juvenile brown trout Salmo trutta captured during outmigrant trapping of rainbow trout suggests that competition and predation may be affecting overwinter survival of rainbow trout in the tributaries. Protection and enhancement of tributary habitat in other reservoirs offers the potential for greater use of wild trout for maintenance of trout fisheries in lentic systems.
Download or read book A Comparison of Growth Rates of Wild Rainbow Trout Oncorhynchus Mykiss in the Upper Sacramento River Before and After the Cantara Spill of 1991 written by Stanley C. Glowacki and published by . This book was released on 2003 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
