{"id":{"repo_id":"utc","oai_identifier":"oai:scholar.utc.edu:theses-1115"},"canonical_url":"https://search.dev.ndltd.org/etd/utc/oai:scholar.utc.edu:theses-1115","repository":{"repo_id":"utc","name":"University of Tennessee - Chattanooga","base_url":"https://scholar.utc.edu/do/oai/"},"display":{"title":"Spatiotemporal patterns in the distribution and abundance of the introduced Redbreast Sunfish (Lepomis auritus) and native Longear Sunfish (L. megalotis; Centrarchidae) in reservoirs of the Tennessee River drainage","abstract":"The Redbreast Sunfish (Lepomis auritus) was introduced in the Tennessee River drainage (TRD) in the 1940s, and contemporary anecdotal evidence suggests that L. auritus is possibly displacing the native Longear Sunfish (Lepomis megalotis). This study aimed to characterize temporal patterns in regional abundances of L. auritus and L. megalotis populations in the TRD based on a multiyear analysis of historical and contemporary fish assemblage datasets (percent abundance, density, biomass). Results indicate that L. megalotis abundance declined in reservoirs where L. auritus was found in high or increasing abundances. Also, L. auritus surpassed L. megalotis in mean percent abundance in Nickajack-Chickamauga River section and has consequently shifted Lepomis species composition. Although it is difficult to isolate causal variables, the interaction of both biotic (i.e., L. auritus competition) and abiotic (i.e., geographic variables, land use, and water quality) factors likely explain the changes in L. megalotis abundance and variability within river sections.","abstract_html":"The Redbreast Sunfish (Lepomis auritus) was introduced in the Tennessee River drainage (TRD) in the 1940s, and contemporary anecdotal evidence suggests that L. auritus is possibly displacing the native Longear Sunfish (Lepomis megalotis). This study aimed to characterize temporal patterns in regional abundances of L. auritus and L. megalotis populations in the TRD based on a multiyear analysis of historical and contemporary fish assemblage datasets (percent abundance, density, biomass). Results indicate that L. megalotis abundance declined in reservoirs where L. auritus was found in high or increasing abundances. Also, L. auritus surpassed L. megalotis in mean percent abundance in Nickajack-Chickamauga River section and has consequently shifted Lepomis species composition. Although it is difficult to isolate causal variables, the interaction of both biotic (i.e., L. auritus competition) and abiotic (i.e., geographic variables, land use, and water quality) factors likely explain the changes in L. megalotis abundance and variability within river sections.","abstract_has_math":false,"creators":["Genard, Lacey Michelle"],"institution":"University of Tennessee at Chattanooga","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Schorr, Mark","Barbosa, Jose; Carroll, Andy; Richards, Sean; Elwell, Jeffery; Walker, Randy","College of Arts and Sciences"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":null,"date_issued":"","date_published":null,"updated_at":"2026-07-24T05:46:11Z","subjects":["Freshwater fishes -- Tennessee River Watershed","Sunfishes -- Tennessee River Watershed","Displacement activity (Animal behavior)"],"languages":["English","eng"],"rights":[],"rights_urls":["https://rightsstatements.org/page/InC/1.0/?language=en"],"identifier_entries":[]},"links":{"outbound_url":"https://scholar.utc.edu/theses/111","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Schorr, Mark","Barbosa, Jose; Carroll, Andy; Richards, Sean; Elwell, Jeffery; Walker, Randy","College of Arts and Sciences"]},{"key":"dc:creator","label":"Author","values":["Genard, Lacey Michelle"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-05-01T07:00:00Z"]},{"key":"dc:publisher","label":"Institution","values":["University of Tennessee at Chattanooga","Chattanooga (Tenn.)"]},{"key":"dc:relation","label":"Dc Relation","values":["Masters Theses and Doctoral Dissertations"]},{"key":"dc:type","label":"Dc Type","values":["Masters theses","Text"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Freshwater fishes -- Tennessee River Watershed","Sunfishes -- Tennessee River Watershed","Displacement activity (Animal behavior)"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["English","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["https://rightsstatements.org/page/InC/1.0/?language=en"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholar.utc.edu/theses/111"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Dept. of Biological and Environmental Sciences","M. S.; A thesis submitted to the faculty of the University of Tennessee at Chattanooga in partial fulfillment of the requirements of the degree of Master of Science."]},{"key":"dc:description.abstract","label":"Abstract","values":["The Redbreast Sunfish (Lepomis auritus) was introduced in the Tennessee River drainage (TRD) in the 1940s, and contemporary anecdotal evidence suggests that L. auritus is possibly displacing the native Longear Sunfish (Lepomis megalotis). This study aimed to characterize temporal patterns in regional abundances of L. auritus and L. megalotis populations in the TRD based on a multiyear analysis of historical and contemporary fish assemblage datasets (percent abundance, density, biomass). Results indicate that L. megalotis abundance declined in reservoirs where L. auritus was found in high or increasing abundances. Also, L. auritus surpassed L. megalotis in mean percent abundance in Nickajack-Chickamauga River section and has consequently shifted Lepomis species composition. Although it is difficult to isolate causal variables, the interaction of both biotic (i.e., L. auritus competition) and abiotic (i.e., geographic variables, land use, and water quality) factors likely explain the changes in L. megalotis abundance and variability within river sections."]},{"key":"dc:title","label":"Title","values":["Spatiotemporal patterns in the distribution and abundance of the introduced Redbreast Sunfish (Lepomis auritus) and native Longear Sunfish (L. megalotis; Centrarchidae) in reservoirs of the Tennessee River drainage"]}]}],"canonical_facts":{"dc:contributor":["Schorr, Mark","Barbosa, Jose; Carroll, Andy; Richards, Sean; Elwell, Jeffery; Walker, Randy","College of Arts and Sciences"],"dc:creator":["Genard, Lacey Michelle"],"dc:date":["2014-05-01T07:00:00Z"],"dc:description":["Dept. of Biological and Environmental Sciences","M. S.; A thesis submitted to the faculty of the University of Tennessee at Chattanooga in partial fulfillment of the requirements of the degree of Master of Science."],"dc:description.abstract":["The Redbreast Sunfish (Lepomis auritus) was introduced in the Tennessee River drainage (TRD) in the 1940s, and contemporary anecdotal evidence suggests that L. auritus is possibly displacing the native Longear Sunfish (Lepomis megalotis). This study aimed to characterize temporal patterns in regional abundances of L. auritus and L. megalotis populations in the TRD based on a multiyear analysis of historical and contemporary fish assemblage datasets (percent abundance, density, biomass). Results indicate that L. megalotis abundance declined in reservoirs where L. auritus was found in high or increasing abundances. Also, L. auritus surpassed L. megalotis in mean percent abundance in Nickajack-Chickamauga River section and has consequently shifted Lepomis species composition. Although it is difficult to isolate causal variables, the interaction of both biotic (i.e., L. auritus competition) and abiotic (i.e., geographic variables, land use, and water quality) factors likely explain the changes in L. megalotis abundance and variability within river sections."],"dc:identifier":["https://scholar.utc.edu/theses/111"],"dc:language":["English","eng"],"dc:publisher":["University of Tennessee at Chattanooga","Chattanooga (Tenn.)"],"dc:relation":["Masters Theses and Doctoral Dissertations"],"dc:rights":["https://rightsstatements.org/page/InC/1.0/?language=en"],"dc:subject":["Freshwater fishes -- Tennessee River Watershed","Sunfishes -- Tennessee River Watershed","Displacement activity (Animal behavior)"],"dc:title":["Spatiotemporal patterns in the distribution and abundance of the introduced Redbreast Sunfish (Lepomis auritus) and native Longear Sunfish (L. megalotis; Centrarchidae) in reservoirs of the Tennessee River drainage"],"dc:type":["Masters theses","Text"]},"updated_at":"2026-07-24T05:46:11Z"}