Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications PDF Download

Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications PDF full book. Access full book title Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications by Matthew R. Campbell. Download full books in PDF and EPUB format.

Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications

Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications PDF Author: Matthew R. Campbell
Publisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 12

Book Description
Since the mid-1920s, the Idaho Department of Fish and Game has cultured Yellowstone cutthroat trout Oncorhynchus clarki bouvieri at Henrys Lake to offset declines in natural production and for use in stocking programs throughout Idaho. Since the mid-1970s, they have also produced F1 hybrids: female Yellowstone cutthroat trout * male rainbow trout O. mykiss. The ability of fishery managers, when selecting broodstock, to visually distinguish returning cutthroat trout from F1 hybrids is, therefore, crucial to avoid accidental introduction of rainbow trout genes into the hatchery-supplemented cutthroat trout population. To evaluate this ability, fish identified by staff as putative cutthroat trout or hybrids (an array of phenotypic characters are used), were sampled during two spawning seasons. Phenotypically identified fish were genetically tested using species-specific restriction fragment length polymorphisms (RFLPs) of nuclear and mitochondrial DNA gene loci and diagnostic allozyme loci. Current levels of rainbow trout introgression in the cutthroat trout population at Henrys Lake were also investigated by analyzing samples collected from the lake and several of its tributaries. Results indicated that staff's phenotypic identifications were highly accurate in distinguishing cutthroat trout from F1 hybrids when selecting broodstock (no F1 hybrids were detected among 80 samples identified as pure). However, backcrosses of F1 hybrids were identified in random collections of adults from the lake as well as fry from Henrys Lake tributaries, indicating introgression. Present levels of rainbow trout introgression are most likely the product of past rainbow trout introductions and limited, intermittent spawning of hatchery-produced F1 hybrids with wild Yellowstone cutthroat, rather than the accidental crossing of F1 hybrids with cutthroat trout at the hatchery. Current levels of introgression are inadvertently maintained by (1) the inability of managers to phenotypically identify and exclude as broodstock individuals with low levels of rainbow trout introgression and (2) the limited, intermittent reproductive success of straying, hatchery-produced F1 hybrids.--Abstract.

Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications

Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications PDF Author: Matthew R. Campbell
Publisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 12

Book Description
Since the mid-1920s, the Idaho Department of Fish and Game has cultured Yellowstone cutthroat trout Oncorhynchus clarki bouvieri at Henrys Lake to offset declines in natural production and for use in stocking programs throughout Idaho. Since the mid-1970s, they have also produced F1 hybrids: female Yellowstone cutthroat trout * male rainbow trout O. mykiss. The ability of fishery managers, when selecting broodstock, to visually distinguish returning cutthroat trout from F1 hybrids is, therefore, crucial to avoid accidental introduction of rainbow trout genes into the hatchery-supplemented cutthroat trout population. To evaluate this ability, fish identified by staff as putative cutthroat trout or hybrids (an array of phenotypic characters are used), were sampled during two spawning seasons. Phenotypically identified fish were genetically tested using species-specific restriction fragment length polymorphisms (RFLPs) of nuclear and mitochondrial DNA gene loci and diagnostic allozyme loci. Current levels of rainbow trout introgression in the cutthroat trout population at Henrys Lake were also investigated by analyzing samples collected from the lake and several of its tributaries. Results indicated that staff's phenotypic identifications were highly accurate in distinguishing cutthroat trout from F1 hybrids when selecting broodstock (no F1 hybrids were detected among 80 samples identified as pure). However, backcrosses of F1 hybrids were identified in random collections of adults from the lake as well as fry from Henrys Lake tributaries, indicating introgression. Present levels of rainbow trout introgression are most likely the product of past rainbow trout introductions and limited, intermittent spawning of hatchery-produced F1 hybrids with wild Yellowstone cutthroat, rather than the accidental crossing of F1 hybrids with cutthroat trout at the hatchery. Current levels of introgression are inadvertently maintained by (1) the inability of managers to phenotypically identify and exclude as broodstock individuals with low levels of rainbow trout introgression and (2) the limited, intermittent reproductive success of straying, hatchery-produced F1 hybrids.--Abstract.

Hybridization and Introgression in a Managed, Native Yellowstone Cutthroat Oncorhynchus Clarki Bouvieri Population, Henrys Lake, Idaho

Hybridization and Introgression in a Managed, Native Yellowstone Cutthroat Oncorhynchus Clarki Bouvieri Population, Henrys Lake, Idaho PDF Author: Matthew Richard Campbell
Publisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 168

Book Description


Genetic Considerations for the Conservation and Management of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) in Yellowstone National Park

Genetic Considerations for the Conservation and Management of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) in Yellowstone National Park PDF Author: David Joel Janetski
Publisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 124

Book Description
A key component to conservation is an accurate understanding of genetic subdivision within a species. Despite their ecological and economic importance, relatively little is understood about the genetic structuring of Yellowstone cutthroat trout in Yellowstone National Park. Here, we use traditional (Fst, Rst, Nm, and AMOVA) and modern (Bayesian assignment tests, coalescent theory, and nested clade analysis) analytical approaches to describe the population genetic subdivision of cutthroat trout spawning populations in Yellowstone Lake and to identify genetically distinct population segments throughout Yellowstone National Park. Evidence for restricted gene flow between spawning populations within Yellowstone Lake was detected using nested clade analysis. This is the first molecular evidence for restricted gene flow between spawning populations in Yellowstone Lake. In contrast, traditional methods such as Fst and Rst as well as the Bayesian clustering program STRUCTURE v2.0 failed to detect evidence for restricted gene flow. Across our sampling range within Yellowstone National Park, eleven genetically distinct cutthroat trout population segments were detected. These showed a general pattern of small, isolated populations with low genetic diversity in headwater streams and wide-spread, genetically diverse populations in higher-order rivers. We recommend populations be managed to maintain current levels of genetic diversity and gene flow. Based on the recent decline of and distinct morphological, behavioral, and genetic nature of cutthroat trout in Yellowstone Lake, we recommend the Yellowstone Lake spawning populations collectively be recognized as an evolutionarily significant unit.

Cutthroat

Cutthroat PDF Author: Pat Trotter
Publisher: Univ of California Press
ISBN: 9780520254589
Category : Nature
Languages : en
Pages : 572

Book Description
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.

Genomic Consequences of Hybridization Between Rainbow and Cutthroat Trout

Genomic Consequences of Hybridization Between Rainbow and Cutthroat Trout PDF Author: Carl O. Ostberg
Publisher:
ISBN:
Category :
Languages : en
Pages : 157

Book Description
Introgressive hybridization creates novel gene combinations that may generate important evolutionary novelty and thus contribute to biological complexity and diversification. On the other hand, hybridization with introduced species can threaten native species, such as cutthroat trout (Oncorhynchus clarkii) following the introduction of rainbow trout (O. mykiss). While rainbow trout introgression in cutthroat trout is well documented, neither the evolutionary consequences nor conservation implications are well understood. Hybridization between rainbow and cutthroat trout occurs in the context of substantial chromosomal rearrangement, as well incompletely re-diploidized genomes. Rainbow and cutthroat trout are descended from an autopolyploid ancestor, and extensive chromosome arm rearrangements have occurred between the species following their divergence from the last common ancestor. Evidence for incomplete re-diploidization includes the occasional formation of multivalents and duplicated loci occasionally exhibit a mixture of disomic and tetrasomic inheritance. Thus, transmission genetics may be complicated by recombination between homeologs. Here, I evaluated the phenotypic and genetic consequences of introgression between rainbow trout and Yellowstone cutthroat trout (O. clarkii bouvieri) to provide insights into genome processes that may help explain how introgression affects hybrid genome evolution. The overall aim of the first part of this dissertation (Chapters 1 and 2) was to evaluate phenotypic variation and gene expression among parental species and hybrids to gain insight into the genetic basis of hybrid and parental morphologies. We constructed seven line crosses: both parental species, both reciprocal F1 hybrids, first-generation backcrosses, and F2 hybrids. In Chapter 1, we aimed to assess the role of introgression on growth (length and weight gain), morphology, and developmental instability among these seven crosses. Growth was related to the proportion of rainbow trout genome contained within crosses. Rainbow and cutthroat trout were morphologically divergent: rainbow trout were generally robust whereas cutthroat trout were typically more slender and their hybrids tended to be morphologically intermediate, although backcrosses were morphologically more similar to their backcrossing parental species. These differences in growth and body morphology may be maintained, in part, through the regulation of muscle growth-related genes. Therefore, in Chapter 2, we aimed to characterize the expression of muscle growth-related genes and to describe relationships between gene expression and growth patterns among parental species and hybrids to gain insight into the underlying genetic basis of the difference in their body shapes. Our findings suggest that rainbow and cutthroat trout exhibit differences in muscle growth regulation, that transcriptional networks may be modified by hybridization, and that hybridization disrupts intrinsic relationships between gene expression and growth patterns that may be functionally important for phenotypic adaptations. The overall aim of the second part of this dissertation (Chapters 3 and 4) was to assess the genetic consequences of introgression to determine how the genomic architecture of hybrids affects allelic inheritance, and thus their subsequent evolution. In Chapter 3, we generated a genetic linkage map for rainbow-Yellowstone cutthroat trout hybrids to evaluate genome process that may influence introgression genome evolution in hybrid populations. Our results suggest that few genomic incompatibilities exist between rainbow and cutthroat trout, allowing their to genomes introgress freely, with the exception that differences in chromosome arrangement between the species may act as barriers to introgression and enable large portions of non-recombined chromosomes to persist within admixed populations. In Chapter 4, we aimed to determine the effect of incomplete re-diploidization on transmission genetics in hybrids, compared to pure species. We used the parental gametic phase from existing genetic linkage maps to identify the homeologs that recombine, to characterize this recombination, and to verify meiotic models of residual tetrasomic inheritance in autotetraploids. Recombination between homeologs occurred frequently in hybrids and results in the non-random segregation of alleles across extended chromosomal regions as well as extensive double-reduction in hybrid parental gametes. Taken together, the results from Chapters 3 and 4 suggested that chromosome rearrangements and recombination of homeologs could influence genome evolution in admixed populations. The research presented in this dissertation indicated that the evolutionary fate of hybrid genomes is unpredictable. Some of our findings suggest that introgressions proceeds in a predictable fashion in admixed populations; rainbow and cutthroat genomes freely introgress, with the exception that chromosome rearrangements may suppress recombination across large chromosomal regions. However, homeologous recombination during meiosis in hybrids results in unpredictable segregation of chromosomes, and the segregation of these chromosomes may depend on the hybrid generation of each parent within an admixed population. Furthermore, phenotype and gene expression are quantitative traits, and expression of these traits may depend on hybrid genotypes across transcriptional networks that are controlled by genes distributed over the entire genome. Consequently, hybridization may alter transcriptional regulation of genes, resulting in unpredictable gene expression patterns, which, in turn, contribute to the high phenotypic variation in hybrids.

Advances in Marine Biology

Advances in Marine Biology PDF Author:
Publisher: Academic Press
ISBN: 0080553699
Category : Science
Languages : en
Pages : 318

Book Description
Advances in Marine Biology was first published in 1963. Now edited by David W. Sims (Marine Biological Association, UK), the serial publishes in-depth and up-to-date reviews on a wide range of topics which will appeal to postgraduates and researchers in marine biology, fisheries science, ecology, zoology, oceanography. Eclectic volumes in the series are supplemented by thematic volumes on such topics as The Biology of Calanoid Copepods and Restocking and Stock Enhancement of Marine Invertebrate Fisheries. * New information on the offspring size in marine invertebrates * Discusses important information on the social structure and strategies of delphinids * More than 250 pages of the latest discoveries in marine science

Hybridization Between Yellowstone Cutthroat Trout and Rainbow Trout in the Upper Snake River Basin, Wyoming

Hybridization Between Yellowstone Cutthroat Trout and Rainbow Trout in the Upper Snake River Basin, Wyoming PDF Author: Ryan P. Kovach
Publisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 11

Book Description
Human-induced hybridization between fish populations and species is a major threat to aquatic biodiversity worldwide and is particularly relevant to management of the subspecies of cutthroat trout Oncorhynchus clarkii. The upper Snake River basin in Wyoming contains one of the largest remaining populations of Yellowstone cutthroat trout O. clarkii bouvieri, a subspecies of special concern throughout its range; however, little is known about levels of hybridization between Yellowstone cutthroat trout and exotic rainbow trout O. mykiss or about the overall genetic population structure for this river basin. There is concern that the Gros Ventre River is a source of hybridization for the Snake River basin. We sampled across the upper Snake River basin to estimate levels of hybridization and population structure and to describe hybrid zone structure and spatial patterns of hybridization throughout the basin. We used this information to help resolve whether the Gros Ventre River was acting as a potential source of hybridization for the upper Snake River basin. We found that Yellowstone cutthroat trout genotypes dominated the river system, but hybridization was detected at low levels in all populations. The Gros Ventre River contained the highest levels of hybridization (population and individual) and displayed evidence of ongoing hybridization between parental genotypes. Levels of hybridization decreased as a function of distance from the Gros Ventre River, suggesting that this population is acting as a source of rainbow trout genes. These patterns were evident despite the fact that levels of genetic connectivity appeared to be higher than those observed in other cutthroat trout populations (global genetic differentiation index F ST = 0.04), and we did not find evidence for genetic isolation by distance. Management actions aimed at reducing the presence of highly hybridized cutthroat trout or rainbow trout individuals in the Gros Ventre River will help to maintain the upper Snake River basin as an important conservation area.

Estimation of Introgression in Cutthroat Trout Populations Using Microsatellites

Estimation of Introgression in Cutthroat Trout Populations Using Microsatellites PDF Author: Victoria L. Pritchard
Publisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 19

Book Description
Introgressive hybridization, mediated by anthropogenic activity, poses a threat to numerous and diverse taxa. The management of introgressed individuals or populations within species of conservation concern is currently the subject of scientific and political debate. We investigate the utility of 10 non-diagnostic microsatellite loci for investigating admixture from introduced Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) and rainbow trout (O. mykiss) within 25 putative Rio Grande cutthroat trout (O. c. virginalis) populations. We apply five different approaches (correspondence analysis, maximum-likelihood assignment tests, an admixture estimator based on allele frequencies, an admixture estimator based on coalescent theory and an admixture estimator implementing a Bayesian method) and use two alternative O. c. virginalis reference samples. All approaches were capable of identifying one population that consisted entirely of introduced O. c. bouvieri, and three out of five approaches enabled us to discriminate those populations with relatively high levels of non-native introgression from those populations with little or none. Actual estimates of admixture coefficients within a test population, varied, however, with the approach and reference sample used. These results have important implications for policies dividing populations into different management categories according to the estimated proportion of non-native genetic material that they contain.

Return to the River

Return to the River PDF Author: Richard N. Williams
Publisher: Elsevier
ISBN: 0080454305
Category : Science
Languages : en
Pages : 720

Book Description
Return to the River will describe a new ecosystem-based approach to the restoration of salmon and steelhead populations in the Columbia River, once one of the most productive river basins for anadromous salmonids on the west coast of North America. The approach of this work has broad applicability to all recovery efforts throughout the northern hemisphere and general applicability to fisheries and aquatic restoration efforts throughout the world. The Pacific Northwest is now embroiled in a major public policy debate over the management and restoration of Pacific salmon. The outcome of the debate has the potential to affect major segments of the region's economy - river transportation, hydroelectric production, irrigated agriculture, urban growth, commercial and sport fisheries, etc. This debate, centered as it is on the salmon in all the rivers, has created a huge demand for information. The book will be a powerful addition to that debate. A 15 year collaboration by a diverse group of scientists working on the management and recovery of salmon, steelhead trout, and wildlife populations in the Pacific Northwest Includes over 200 figures, with four-color throughout the book Discusses complex issues such as habitat degradation, juvenile survival through the hydrosystem, the role of artificial production, and harvest reform

Chromosome Rearrangements, Recombination Suppression, and Limited Segregation Distortion in Hybrids Between Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) and Rainbow Trout (O. Mykiss)

Chromosome Rearrangements, Recombination Suppression, and Limited Segregation Distortion in Hybrids Between Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) and Rainbow Trout (O. Mykiss) PDF Author: Carl O. Ostberg
Publisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 16

Book Description
Background Introgressive hybridization is an important evolutionary process that can lead to the creation of novel genome structures and thus potentially new genetic variation for selection to act upon. On the other hand, hybridization with introduced species can threaten native species, such as cutthroat trout (Oncorhynchus clarkii) following the introduction of rainbow trout (O. mykiss). Neither the evolutionary consequences nor conservation implications of rainbow trout introgression in cutthroat trout is well understood. Therefore, we generated a genetic linkage map for rainbow-Yellowstone cutthroat trout (O. clarkii bouvieri) hybrids to evaluate genome processes that may help explain how introgression affects hybrid genome evolution. Results The hybrid map closely aligned with the rainbow trout map (a cutthroat trout map does not exist), sharing all but one linkage group. This linkage group (RYHyb20) represented a fusion between an acrocentric (Omy28) and a metacentric chromosome (Omy20) in rainbow trout. Additional mapping in Yellowstone cutthroat trout indicated the two rainbow trout homologues were fused in the Yellowstone genome. Variation in the number of hybrid linkage groups (28 or 29) likely depended on a Robertsonian rearrangement polymorphism within the rainbow trout stock. Comparison between the female-merged F1 map and a female consensus rainbow trout map revealed that introgression suppressed recombination across large genomic regions in 5 hybrid linkage groups. Two of these linkage groups (RYHyb20 and RYHyb25_29) contained confirmed chromosome rearrangements between rainbow and Yellowstone cutthroat trout indicating that rearrangements may suppress recombination. The frequency of allelic and genotypic segregation distortion varied among parents and families, suggesting few incompatibilities exist between rainbow and Yellowstone cutthroat trout genomes.