Freshwater ecosystems in East Texas contain a rich freshwater biodiversity, with the Neches and Sabine River basins supporting some of the greatest freshwater fish diversity in the state. Given the heterogeneity of habitats and species diversity, these rivers serve as excellent natural systems for examining the ecological processes shaping biodiversity patterns and species distributions. In 2023-2024, 60 streams in the Neches and Sabine River basins were surveyed across three seasons to investigate the patterns and ecological drivers of taxonomic (TDβ), functional (FDβ), and phylogenetic β-diversity (PDβ) facets of freshwater fish assemblages. Additionally, I created two ecological niche models for a Species of Greatest Conservation Need (SGCN), Spotted Sucker Minytrema melanops, to compare model accuracy and inform conservation efforts of the species in these basins. The results of this study revealed that β-diversity facets of fish assemblages were correlated yet influenced by different combinations of regional and local factors (e.g., stream order, wetted width, different land cover types). The ecological niche model created using random forest algorithms outperformed the maximum entropy approach, and factors related to channel morphology (e.g., stream order, slope) and land cover type (e.g., agriculture) were important predictors of species occurrence.
","abstract_html":"<p>Freshwater ecosystems in East Texas contain a rich freshwater biodiversity, with the Neches and Sabine River basins supporting some of the greatest freshwater fish diversity in the state. Given the heterogeneity of habitats and species diversity, these rivers serve as excellent natural systems for examining the ecological processes shaping biodiversity patterns and species distributions. In 2023-2024, 60 streams in the Neches and Sabine River basins were surveyed across three seasons to investigate the patterns and ecological drivers of taxonomic (TDβ), functional (FDβ), and phylogenetic β-diversity (PDβ) facets of freshwater fish assemblages. Additionally, I created two ecological niche models for a Species of Greatest Conservation Need (SGCN), Spotted Sucker <em>Minytrema melanops</em>, to compare model accuracy and inform conservation efforts of the species in these basins. The results of this study revealed that β-diversity facets of fish assemblages were correlated yet influenced by different combinations of regional and local factors (e.g., stream order, wetted width, different land cover types). The ecological niche model created using random forest algorithms outperformed the maximum entropy approach, and factors related to channel morphology (e.g., stream order, slope) and land cover type (e.g., agriculture) were important predictors of species occurrence.</p>","abstract_has_math":false,"creators":["Umstott, Anastasia M"],"institution":null,"degree_name":"Master of Science - Biology","degree_level":"Thesis","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":["Carmen G. Montaña","Reuber Antoniazzi","Brent Burt"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025-05-08T07:00:00Z","date_published":"2025-05-08T07:00:00Z","updated_at":"2026-07-24T04:30:45Z","subjects":["stream fish communities","beta diversity","multi-scale","SGCN","modeling","East Texas","Terrestrial and Aquatic Ecology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholarworks.sfasu.edu/etds/593","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Carmen G. Montaña","Reuber Antoniazzi","Brent Burt"]},{"key":"dc:creator","label":"Author","values":["Umstott, Anastasia M"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2026-05-09T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science - Biology"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["stream fish communities","beta diversity","multi-scale","SGCN","modeling","East Texas","Terrestrial and Aquatic Ecology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholarworks.sfasu.edu/etds/593"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Freshwater ecosystems in East Texas contain a rich freshwater biodiversity, with the Neches and Sabine River basins supporting some of the greatest freshwater fish diversity in the state. Given the heterogeneity of habitats and species diversity, these rivers serve as excellent natural systems for examining the ecological processes shaping biodiversity patterns and species distributions. In 2023-2024, 60 streams in the Neches and Sabine River basins were surveyed across three seasons to investigate the patterns and ecological drivers of taxonomic (TDβ), functional (FDβ), and phylogenetic β-diversity (PDβ) facets of freshwater fish assemblages. Additionally, I created two ecological niche models for a Species of Greatest Conservation Need (SGCN), Spotted Sucker Minytrema melanops, to compare model accuracy and inform conservation efforts of the species in these basins. The results of this study revealed that β-diversity facets of fish assemblages were correlated yet influenced by different combinations of regional and local factors (e.g., stream order, wetted width, different land cover types). The ecological niche model created using random forest algorithms outperformed the maximum entropy approach, and factors related to channel morphology (e.g., stream order, slope) and land cover type (e.g., agriculture) were important predictors of species occurrence.
"]},{"key":"dc:title","label":"Title","values":["Patterns of Taxonomic, Functional, and Phylogenetic Diversity, and Ecological Drivers of Stream Fish Assemblages in East Texas"]}]}],"canonical_facts":{"dc:contributor":["Carmen G. Montaña","Reuber Antoniazzi","Brent Burt"],"dc:creator":["Umstott, Anastasia M"],"dc:date.available":["2026-05-09T07:00:00Z"],"dc:description.abstract":["Freshwater ecosystems in East Texas contain a rich freshwater biodiversity, with the Neches and Sabine River basins supporting some of the greatest freshwater fish diversity in the state. Given the heterogeneity of habitats and species diversity, these rivers serve as excellent natural systems for examining the ecological processes shaping biodiversity patterns and species distributions. In 2023-2024, 60 streams in the Neches and Sabine River basins were surveyed across three seasons to investigate the patterns and ecological drivers of taxonomic (TDβ), functional (FDβ), and phylogenetic β-diversity (PDβ) facets of freshwater fish assemblages. Additionally, I created two ecological niche models for a Species of Greatest Conservation Need (SGCN), Spotted Sucker Minytrema melanops, to compare model accuracy and inform conservation efforts of the species in these basins. The results of this study revealed that β-diversity facets of fish assemblages were correlated yet influenced by different combinations of regional and local factors (e.g., stream order, wetted width, different land cover types). The ecological niche model created using random forest algorithms outperformed the maximum entropy approach, and factors related to channel morphology (e.g., stream order, slope) and land cover type (e.g., agriculture) were important predictors of species occurrence.
"],"dc:identifier":["https://scholarworks.sfasu.edu/etds/593"],"dc:subject":["stream fish communities","beta diversity","multi-scale","SGCN","modeling","East Texas","Terrestrial and Aquatic Ecology"],"dc:title":["Patterns of Taxonomic, Functional, and Phylogenetic Diversity, and Ecological Drivers of Stream Fish Assemblages in East Texas"],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Science - Biology"]},"updated_at":"2026-07-24T04:30:45Z"}