Download or read book Population Genetic Structure of Unionid Mussels Across Multiple Gulf Drainages written by Matthew Stewart Harrison and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding patterns of genetic differentiation within and across wildlife populations is a key component to parsing the demographic and ecological processes that govern the spatial structure and evolutionary trends of a given species. As molecular and computational techniques continue to advance, these data have become critical tools in delineating population boundaries as well as informing appropriate management decisions. This study utilized a genotyping by sequencing (GBS) approach to study the genetic structure of three Texas state threatened mussel species of family Unionidae: Pleurobema riddellii (Louisiana Pigtoe), Fusconaia askewi (Texas Pigtoe), and Potamilus amphichaenus (Texas Heelsplitter). Principal component and admixture analyses paired with genetic distance estimates (GST) of these species demonstrated clear interspecific and intraspecific differentiation across separate drainages as well as indications of isolation within drainages potentially facilitated by geographic barriers such as river impoundments and local environmental and ecological differences. These data present an effective approach to modeling genetic structure across a landscape that allow for precise inferences on population boundaries that inform conservation units (CU's) and the management strategies that use them (Funk et al., 2012; Smith et al., 2021).
Download or read book The Population Genetic Structure of Quadrula Aurea Bivalvia Unionidae A Threatened Freshwater Mussel in Central Texas written by Jeffrey A. Mabe and published by . This book was released on 2018 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: The anthropogenic alteration of riverine ecosystems has led to declines in the abundance and diversity of freshwater mussels (Bivalvia: Unionoida) worldwide. Central Texas is home to a diverse freshwater mussel fauna including three candidates for federal listing under the Endangered Species Act. Surveys conducted over the last few decades suggest many of the endemic freshwater mussel species in Texas exist in small isolated populations that may be vulnerable to the deleterious effects of genetic diversity loss. Microsatellite primers from two closely related species were used to identify a set of genetic markers that functioned in the Golden Orb (Quadrula aurea). Microsatellite markers were then applied to document the population genetic structure of Q. aurea within and among three connected river drainages in southeastern Texas. Gene flow within existing Q. aurea populations appears high indicating little potential for genetic issues stemming from isolation and inbreeding. Two weakly divergent admixed populations were identified occupying the San Antonio and Guadalupe/San Marcos rivers. Population genetic structure was related to river basin affiliation, but results for environmental factors were unresolved. Current effective population size estimates are large for the Guadalupe/San Marcos drainage and moderately large for the San Antonio drainage and there is no clear genetic evidence of contemporary population declines. Transport in the glochidial phase by a highly mobile host fish, the channel catfish (Ictalurus punctatus), may provide a mechanism for maintaining connectivity among spatially discrete mussel beds and deserves further study. Information on the occurrence and habitat associations of Q. aurea and two other threatened freshwater mussel species was documented. Quantification of the population genetic structure for Q. aurea provides important information needed for the management of this species, a baseline for understanding future changes, and insight into the factors that shape the population genetic structure of other threatened unionids in Texas.
Download or read book Comparative Conservation Genomics of a Suite of Imperiled Freshwater Mussels written by Scott Meyer and published by . This book was released on 2021 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maintenance of genetic diversity is a critical component to the management and recovery of imperiled species. By ensuring that a species’ genetic diversity is maintained, issues like inbreeding depression and loss of local adaptation can be prevented. However, the genetic diversity of many species are not well-characterized, and the factors that influence a species’ genetic diversity are often not well understood. In the case of imperiled unionid freshwater mussels, it is important to conduct conservation genetic assessments to aid in their management and preserve genetic diversity. This is the first study to conduct a comparative conservation genomic assessment for eight unionid species. By sequencing 3RAD libraries, I characterized single-nucleotide-polymorphism (SNP) variation in these species across their ranges in North Carolina and beyond. I obtained thousands of neutral SNPs across the genome for each focal species. With the newly obtained genomic data and associated spatial data I addressed three main questions: 1) What is each species’ population structure and how is genetic diversity distributed across the landscape? 2) Which landscape factors have the strongest influence on population genetic structure and diversity? 3) How do life-history traits mediate species’ genetic responses to landscape factors? I observed that population structure was rarely observed below the spatial scale of basin or watershed, suggesting substantial gene flow occurs among connected streams in the same watershed. I found that fluvial distance and the type of barriers between locations were the most significant drivers of genetic differentiation among individuals, whereas drainage area was the most significant, landscape variable, driver of genetic diversity within individuals. Individuals occupying sites with relatively small upstream watershed areas (2), little human development (70%) exhibited the highest heterozygosity. Life-history traits such as longevity and fecundity appeared to mediate genetic diversity within individuals. Species with “slower” life-histories (lower fecundity, longer lifespans) exhibited higher genetic diversity than species with “faster” life-histories (higher fecundity, shorter lifespans). Including life-history traits in a conservation genomic assessment provides novel insights into evolutionary ecology that helps to explain or predict the genetic response of a species to their environment.
Download or read book Population Genetic Structure and Taxonomic Evaluation of Two Closely Related Freshwater Mussel Species the Eastern Floater Pyganodon Cataracta and the Newfoundland Floater Pyganodon Fragilis in Atlantic Canada written by Ljiljana Marija Stanton and published by . This book was released on 2008 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conservation Genetics of a Near Threatened Freshwater Mussel Species Lampsilis Cardium and Improved Prospects for Recovery written by Chad D. Ferguson and published by . This book was released on 2009 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Freshwater mussels (Bivalvia: Unionidae) are among the most imperiled organisms in North America. While there is an urgent need for effective conservation planning and management of these organisms, important basic biological information is lacking. This research characterizes levels of genetic diversity and population structure in the Near Threatened (IUCN) freshwater mussel Lampsilis cardium in populations from Twin Creek (southwest Ohio), Little Darby and Big Darby Creeks (central Ohio), and Little Muskingum River (eastern Ohio) and assesses the extent to which regional geological events explain population structuring. Data from the congener Lampsilis ovata from Clinch River (Tennessee) are included for comparison. To characterize these patterns, sequencing of the mtDNA gene cytochrome oxidase c subunit 1 (COI) and nuclear microsatellite genotyping over 12 loci was performed. Additionally, genotype data from both adults and individual glochidia were analyzed to examine parentage and within-population levels of relatedness across common pedigree relationships. Microsatellite data reveal weak population structuring across glaciated and unglaciated drainages and 900 total river miles. However, haplotype analysis and sequence alignment recovered deeply divergent, cryptic lineages within Lampsilis cardium consistent with ancestral introgressive hybridization with Lampsilis ovata or incomplete lineage sorting. Mito-nuclear discordance argues against ongoing hybridization, although polymorphic species are also consistent with the data, and this affirms the importance of multiple molecular markers. In addition to finding multiple paternity in single broods, a number of parent-offspring, full-sibling, and half-sibling relationships for adults and glochidia are described. Numerous instances are noted in which likely full-siblings or half-siblings were located several kilometers apart, demonstrating that DNA-based evidence can describe the spatial nature of dispersal in unionid mussels. In a first report, the likely father of three glochidia from one female's brood was identified 16.2 kilometers upstream, which suggests the possibility of long-distance transport of spermatozoa in Lampsilis cardium. Given the similarity with which Lampsilines reproduce, it is predicted that other members of this genus are also capable long-distance fertilization. If fertilization in populations of freshwater mussels is indeed not limited by the density of breeding adults, the prospects for recovery in this fauna may be better than recently imagined.
Download or read book Population Genetic Structure and Taxonomic Evaluation of Two Closely Related Freshwater Mussel Species the Eastern Floater Pyganodon Cataracta and the Newfoundland Floater P Fragilis in Atlantic Canada written by Ljiljana Marija Stanton and published by . This book was released on 2008 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Population Genetic Structure and Taxonomic Evaluation of Two Closely Related Freshwater Mussel Species the Eastern Floater Pyganodon Cataracta and the Newfoundland Floater Pyganodon Fragilis in Atlantic Canada written by Ljiljana Marija Stanton and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Population Genetic Structure of the Freshwater Mussel Lampsilis Siliquoidea bivalvia Unionidae in the Darby Creek Watershed Central Ohio written by Marnin D. Wolfe and published by . This book was released on 2006 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evolution Population Genetics and Conservation of Lampsiline Freshwater Mussels Bivalvia written by David Thomas Zanatta and published by . This book was released on 2008 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: The biodiversity of freshwater mussels is diminishing at a nearly unprecedented pace, with many species being added to legally protected lists. In response to this imperilment, this dissertation investigates the evolution and population genetics of mussels from the tribe Lampsilini of freshwater mussels. Species in the Order Unionoida require a host, usually a fish, to complete their life cycle. Females of most species show adaptations that increase the chances of glochidia larvae contacting a host. Using a suite of mitochondrial DNA sequences, a phylogenetic hypothesis for the evolution of the lampsiline species was created to test the evolution of host attracting structures and behaviours. It is necessary to investigate alternative ways to conserve the biological and genetic diversity of imperiled unionoids within the framework of conservation law. In order to clarify definitions and concepts for conservation units for unionoids, studies of unionoid evolution, population genetic structure, cryptic species, and taxonomic conflict are discussed. From this synthesis of studies, recommendations are made for the appropriate usage of these units under endangered species legislation. To assist in managing lampsiline species, population-level studies of the imperiled Northern Riffleshell (Epioblasma torulosa rangiana), Snuffbox (E. triquetra) and Wavy-rayed Lampmussel (Lampsilis fasciola) were conducted to test possible routes of post-glacial redistribution and for the existence of conservation units, population structure and genetic diversity. Analyses were made using mitochondrial DNA sequences and microsatellite loci, including six that were newly developed. For E. t. rangiana, mtDNA sequence data did not indicate significant geographic structure among populations. However, allelic data from the microsatellite loci revealed highly significant population structuring. For E. triquetra, the results indicated the occurrence of three glacial refugia: the Tennessee River, rivers south of the Ozark Crest, and the lower Ohio River drainage near the confluence with the Mississippi. The four sympatrically-occurring mantle display-types could not be distinguished genetically via an assessment of microsatellite DNA loci. Within-drainage gene flow was high and sampling localities within drainages displayed panmixia. For all species, efforts in artificial propagation and possible translocations programs to reintroduce or augment populations should be made to maintain significant levels of genetic variation while maintaining distinctiveness.
Download or read book Genetic Portraits of Introduced Gobies and Mussels written by Joshua E. Brown and published by . This book was released on 2009 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: The growing numbers of species introductions, with many having significant ecological and economic impacts, constitute one of the greatest challenges facing our native ecosystems today. To make correct ecological comparisons among native and introduced populations and minimize their further spread, we must (1) identify the introduced species/taxon/population correctly and (2) determine its source population(s) and its transmission pathways. This dissertation study analyzes and compares the population genetic and phylogeographic structure of three successful invasions by Ponto-Caspian species into the North American Great Lakes and beyond: the round goby Neogobius melanostomus and the dreissenid mussels Dreissena polymorpha and Dreissena rostriformis bugensis. In Chapters 2 and 3 we describe evidence for two subspecies of round goby, both of which have expanded their range. From this background information, likely sources are identified for invasive populations in Eurasia and North America. In Chapter 4, the genetic structure of zebra and quagga mussels in North America is analyzed in comparison with sites in Eurasia. Zebra mussel populations have appreciable genetic diversity, whereas quagga mussel populations from the Colorado River and California show some founder effects. The population genetic composition of both species changed over time at given sites; with some adding alleles from adjacent populations, some losing them, and all retaining closest similarity to their original composition. Zebra and quagga mussels from the western United States assign to possible origins from the St. Lawrence River and Lake Ontario, respectively. These assignments suggest that overland colonization pathways via recreational boats do not necessarily reflect the most proximate connections. The results show that all three species likely experienced multiple introductions into the Great Lakes, which brought a large proportion of the native genetic diversity to North America. This created significant genetic structure within their respective introduced ranges. The round goby and the quagga mussel were introduced from their native range, in contrast to the zebra mussel which whose origins North American origins trace to secondary spread from previously invaded regions in Northern and Central Europe. This dissertation demonstrates the utility of molecular techniques to invasive species management, by identifying the pathways connecting source populations to new colonies.
Download or read book Phylogeography and Genetic Structure of Two Freshwater Mussel Species Bivalvia Unionidae Along Hypothesized Post glacial Dispersal Routes Into the Laurentian Great Lakes written by Trevor L. Hewitt and published by . This book was released on 2015 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessment of Genetic Diversity and Structure Among Populations of the Freshwater Mussel Epioblasma Triquetra in the Laurentian Great Lakes Drainage written by Caitlin Beaver and published by . This book was released on 2018 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Federal Register written by and published by . This book was released on 2012-10 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Habitat Use and Community Structure of Unionid Mussels in Three Lake Erie Tributaries written by Jeffrey D. Grabarkiewicz and published by . This book was released on 2012 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nearly 300 species of freshwater mussels (Bivalvia: Superfamily Unionoidea) have been documented in the United States. Unfortunately, this diversity is in peril, with 76 species currently listed as threatened or endangered under the Endangered Species Act. This research established unionid population estimates and habitat use within six reaches of three Western Lake Erie tributaries: the Blanchard River, Swan Creek, and Beaver Creek. Particular emphasis was placed on the federally endangered Rayed Bean (Villosa fabalis). Quantitative sampling documented 22 live unionid species and 1,197 live individuals across all reaches and streams. Evidence of recent recruitment was documented for 10 species and size class diversity was found for 15 species. Unionid density and species richness were highest in the Upper Blanchard with a mean reach density of 4.48 unionids per m2 and 15 live species. Rayed Bean (V. fabalis) were estimated at 0.29 per m2 in the Upper Blanchard and 0.13 per m2 in Middle Swan Creek. Size class diversity for V. fabalis was found in both reaches, with many young individuals (
Download or read book North American Freshwater Mussels written by Wendell R. Haag and published by Cambridge University Press. This book was released on 2012-08-27 with total page 523 pages. Available in PDF, EPUB and Kindle. Book excerpt: Synthesizes the ecology and natural history of North American freshwater mussels for scientists, natural resource professionals, students and natural history enthusiasts.
Download or read book Freshwater Mussels of Florida written by James D. Williams and published by University of Alabama Press. This book was released on 2014-09-30 with total page 525 pages. Available in PDF, EPUB and Kindle. Book excerpt: Freshwater Mussels of Florida is the only comprehensive, illustrated encyclopedia of all recorded species of mussels in the state of Florida.
Download or read book Freshwater Biodiversity written by David Dudgeon and published by Cambridge University Press. This book was released on 2020-05-21 with total page 517 pages. Available in PDF, EPUB and Kindle. Book excerpt: Growing human populations and higher demands for water impose increasing impacts and stresses upon freshwater biodiversity. Their combined effects have made these animals more endangered than their terrestrial and marine counterparts. Overuse and contamination of water, overexploitation and overfishing, introduction of alien species, and alteration of natural flow regimes have led to a 'great thinning' and declines in abundance of freshwater animals, a 'great shrinking' in body size with reductions in large species, and a 'great mixing' whereby the spread of introduced species has tended to homogenize previously dissimilar communities in different parts of the world. Climate change and warming temperatures will alter global water availability, and exacerbate the other threat factors. What conservation action is needed to halt or reverse these trends, and preserve freshwater biodiversity in a rapidly changing world? This book offers the tools and approaches that can be deployed to help conserve freshwater biodiversity.
