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 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 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 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 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 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 Rio Grande Cutthroat Trout Oncorhynchus Clarki Virginalis written by Connie Keeler-Foster and published by . This book was released on 2003 with total page 830 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Genomic and Fitness Consequences of Hybridization Between Cutthroat and Rainbow Trout written by Daniel P. Drinan and published by . This book was released on 2015 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hybridization is an important and common evolutionary process that can contribute to diversification, adaptation, and speciation. When species hybridize, divergent genomes are combined through recombination and may result in phenotypic changes. Such phenotypic changes may be the result of differences in chromosomal structure or adaptive divergence between the parental species and may ultimately affect fitness. Understanding how phenotypes change following hybridization, as well as the genetic mechanisms responsible for changes is critical for understanding divergent selection, speciation, and identifying populations that may be at risk from hybridization. Here, the effect of hybridization between cutthroat (Oncorhynchus clarkii) and rainbow trout (O. mykiss) on fitness was investigated using three techniques. In the first chapter, fitness influencing traits were compared among individuals at various hybridization levels. In the second chapter, genomic changes that could affect fitness were identified in the hybrid relative to rainbow trout. And, in the third chapter, correlations between reproductive success and hybridization were investigated in a wild population, as well as the genomic and ecological mechanisms responsible for those changes. The first chapter of this dissertation aimed to identify how traits potentially involved in fitness (embryonic survival, ova size, ova energy concentration, sperm motility, burst swimming performance, juvenile survival, and juvenile growth) changed with hybridization between cutthroat and rainbow trout and whether those changes could explain previously observed reductions in reproductive success of individuals with increased rainbow trout ancestry. Using progeny from wild caught fish, differences in phenotypes based on hybridization were observed for embryonic survival, ova energy concentration, juvenile weight, and burst swimming based on ancestry. However, the correlations differed from previously observed patterns of reproductive success and likely do not explain declines in reproductive success associated with hybridization. The second chapter of this dissertation aimed to identify how hybridization affects the genome by identifying genomic regions with changes in recombination rates in the hybrid relative to rainbow trout as well as genomic areas with excess species-specific ancestry in the hybrid. Previous studies of hybridization have observed recombination suppression in genomic regions where structural differences, such as inversions or karyotype differences, exist between parental species. Such regions may retain groups of adaptive alleles. Additionally, adaptive divergence between the parental species may result in alleles that are preferentially selected in the hybrid progeny. Identification of regions with suppressed recombination or excess species-specific ancestry would provide insight into markers that may be important to fitness and that have differentially evolved in each of the parental species. In total, eight and seven chromosomes were identified to have changes in recombination rates in the hybrid female and male relative to O. mykiss. Recombination was suppressed in the hybrids on two chromosomes with known structural differences between the parental species. In addition, changes in recombination rates were observed on five chromosomes with high proportions of duplicated markers and may be due to increased homeologous chromosome pairing. Recombination patterns were similar between the sexes which suggests that hybridization affects recombination in the same way in females and males. Regions of excess species-specific ancestry covered 11 and 10% of the mapped genome in the female and male and regions of excess were evenly split between cutthroat trout and O. mykiss. Genetic drift may be responsible for much of the observed patterns of excess species-specific ancestry, but selection may also play a role. The aim of the third chapter of this dissertation was to identify the fitness consequences of hybridization, mechanisms responsible for the retention of hybridization, and genomic regions correlated with changes in reproductive success in a wild population of westslope cutthroat trout hybridized with non-native rainbow trout. Adult samples from a previous study, collected over a five year period, were sequenced at 3027 loci. Increased admixture from non-native rainbow trout had a strong, negative effect on reproductive success. A decline of 53% was observed for individuals with an increased genetic contribution of 0.20 from rainbow trout. Despite apparent strong selection against rainbow trout ancestry, hybridization appears to be maintained largely by the invasion of rainbow trout from outside populations as well as the relatively high fitness of few hybrid individuals. Ten loci correlated with reproductive success were identified in females. Seven of the ten loci were linked to chromosomes and three were positioned on chromosomes. Loci linked to reproductive success were identified on chromosomes with excess species-specific ancestry in hybrid progeny (RYHyb14 and RYHyb18) as well as chromosomes with a high proportion of duplicated markers (RYHyb02) and known Robertsonian polymorphism (RYHyb20). The research presented in this dissertation will elucidate our understanding of the phenotypic and genetic changes correlated with hybridization between rainbow and cutthroat trout as well as identify genetic and ecological mechanisms that may be responsible for those changes. In addition, results from this study provide insight into differences in adaptive divergence and markers that may be involved in the early stages of speciation in the wild. Results could be used by managers to identify populations that are at risk from hybridization.

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 Hybridization Between Yellowstone Cutthroat Trout and Rainbow Trout in the Upper Snake River Basin Wyoming written by Ryan P. Kovach and published by . This book was released on 2011 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

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 Hybridization Between Yellowstone Cutthroat Trout and Rainbow Trout Alters the Expression of Muscle Growth Related Genes and Their Relationships with Growth Patterns written by Carl O. Ostberg and published by . This book was released on 2015 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hybridization creates novel gene combinations that may generate important evolutionary novelty, but may also reduce existing adaptation by interrupting inherent biological processes, such as genotype-environment interactions. Hybridization often causes substantial change in patterns of gene expression, which, in turn, may cause phenotypic change. Rainbow trout (Oncorhynchus mykiss) and cutthroat trout (O. clarkii) produce viable hybrids in the wild, and introgressive hybridization with introduced rainbow trout is a major conservation concern for native cutthroat trout. The two species differ in body shape, which is likely an evolutionary adaptation to their native environments, and their hybrids tend to show intermediate morphology. The characterization of gene expression patterns may provide insights on the genetic basis of hybrid and parental morphologies, as well as on the ecological performance of hybrids in the wild. Here, we evaluated the expression of eight growth-related genes (MSTN-1a, MSTN-1b, MyoD1a, MyoD1b, MRF-4, IGF-1, IGF-2, and CAST-L) and the relationship of these genes with growth traits (length, weight, and condition factor) in six line crosses: both parental species, both reciprocal F1 hybrids, and both first-generation backcrosses (F1 x rainbow trout and F1 x cutthroat trout). Four of these genes were differentially expressed among rainbow, cutthroat, and their hybrids. Transcript abundance was significantly correlated with growth traits across the parent species, but not across hybrids. 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.

Download or read book Ecological and Environmental Investigations of Competition Between Native Yellowstone Cutthroat Trout Oncorhynchus Clarkii Bouvieri Rainbow Trout Oncorhynchus Mykiss and Their Hybrids written by Steven Michael Seiler and published by . This book was released on 2007 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduced species can have dramatic impacts within the native communities where they become established. In western North America, native cutthroat trout (Oncorhynchus clarkii) are experiencing drastic declines due to habitat alteration and fish introductions. Rainbow trout ( O. mykiss) are thought to be especially detrimental to cutthroat trout because they share similar life histories and can form fertile hybrid offspring, compounding interspecific competition through added pressure from hybrids. My dissertation consists of five studies developed to test ecological and environmental factors that may influence the spread of rainbow trout and cutthroat-rainbow hybrid trout within native Yellowstone cutthroat trout ( O. c. bouvieri) populations. I raised Yellowstone cutthroat trout, rainbow trout, and reciprocal first generation hybrids under common conditions and tested for differences in morphology and swimming stamina (Chapter 1), aggression and foraging ability (Chapter 2), and the strength of interspecific competition on the growth rate of Yellowstone cutthroat trout (Chapter 3). I also surveyed trout and environmental characteristics from the South Fork of the Snake River watershed to test for morphological differences between wild Yellowstone cutthroat trout, rainbow trout, and hybrids (Chapter 4) and to examine the influence of environmental characteristics on the extent of hybridization (Chapter 5). I found differences in morphology, swimming stamina, foraging behavior, and growth between Yellowstone cutthroat trout, rainbow trout, and their hybrids that place cutthroat trout at a disadvantage. The field survey found body shape differences between Yellowstone cutthroat trout, rainbow trout, and hybrids consistent with those of trout raised in the laboratory with high predictability of genetic class based on morphology alone. The degree of hybridization present at field sampling locations was related to the size of the stream and summer water temperature of the sampling location; however, level of hybridization could also be the result of distance from a location where most rainbow trout were stocked. My work provides some of the first tests of competition between cutthroat trout and rainbow trout and the influence of hybridization. This dissertation will aid in cutthroat trout conservation efforts and be of general interest to invasive species ecologists in better understanding the dynamics of invasive species success.

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 Genomic Consequences of Hybridization Between Rainbow and Cutthroat Trout written by Carl O. Ostberg and published by . This book was released on 2015 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Chromosome Rearrangements Recombination Suppression and Limited Segregation Distortion in Hybrids Between Yellowstone Cutthroat Trout Oncorhynchus Clarkii Bouvieri and Rainbow Trout O Mykiss written by Carl O. Ostberg and published by . This book was released on 2013 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.