Mary Freeman, Ph.D.
Mary Freeman is a research ecologist with the Eastern Ecological Science Center at Athens, GA.
She received a B.S. in biology (1979), a M.S. in entomology (1982) and a Ph.D. in forest resources (1990) from the University of Georgia. Before joining Patuxent, Mary conducted research for the U.S. Fish and Wildlife Service and the National Biological Service in Auburn, AL (1992-1996). Mary serves as affiliate faculty at the Odum School of Ecology, University of Georgia, and on the graduate faculties at the University of Georgia and Auburn University.
Science and Products
Filter Total Items: 107
Analysis of spawning behavior, habitat, and season of the federally threatened Etheostoma scotti, Cherokee darter (Osteichthyes: Percidae)
Etheostoma scotti (Cherokee darter) is a member of the subgenus Ulocentra and a federally threatened endemic to the Etowah River system, GA. Field observations of spawning behavior of the Cherokee darter were made at five stream sites to identify spawning season and habitat over two field seasons. Cherokee darters primarily spawn in pool habitats between mid-March and early June, at temperatures
Authors
C.M. Storey, B.A. Porter, Mary C. Freeman, B. J. Freeman
Importance of riparian forests in urban catchments contingent on sediment and hydrologic regimes
Forested riparian corridors are thought to minimize impacts of landscape disturbance on stream ecosystems; yet, the effectiveness of streamside forests in mitigating disturbance in urbanizing catchments is unknown. We expected that riparian forests would provide minimal benefits for fish assemblages in streams that are highly impaired by sediment or hydrologic alteration. We tested this hypothesis
Authors
A.H. Roy, Mary C. Freeman, B. J. Freeman, S.J. Wenger, J.L. Meyer, W.E. Ensign
Fish-assemblage variation between geologically defined regions and across a longitudinal gradient in the Monkey River Basin, Belize
Linkages between geology and fish assemblages have been inferred in many regions throughout the world, but no studies have yet investigated whether fish assemblages differ across geologies in Mesoamerica. The goals of our study were to: 1) compare physicochemical conditions and fish-assemblage structure across 2 geologic types in headwaters of the Monkey River Basin, Belize, and 2) describe basin-
Authors
P.C. Esselman, Mary C. Freeman, C. M. Pringle
Reach-scale effects of riparian forest cover on urban stream ecosystems
We compared habitat and biota between paired open and forested reaches within five small streams (basin area 10?20 km2) in suburban catchments (9%?49% urban land cover) in the Piedmont of Georgia, USA. Stream reaches with open canopies were narrower than forested reaches (4.1 versus 5.0 m, respectively). There were no differences in habitat diversity (variation in velocity, depth, or bed particl
Authors
A.H. Roy, C.L. Faust, Mary C. Freeman, J.L. Meyer
Investigating hydrologic alteration as a mechanism of fish assemblage shifts in urbanizing streams
Stream biota in urban and suburban settings are thought to be impaired by altered hydrology; however, it is unknown what aspects of the hydrograph alter fish assemblage structure and which fishes are most vulnerable to hydrologic alterations in small streams. We quantified hydrologic variables and fish assemblages in 30 small streams and their subcatchments (area 8–20 km2) in the Etowah River Catc
Authors
A.H. Roy, Mary C. Freeman, B. J. Freeman, S.J. Wenger, W.E. Ensign, J.L. Meyer
Urbanization effects on fishes and habitat quality in a southern Piedmont river basin
We quantified the relationships among urban land cover, fishes, and habitat quality to determine how fish assemblages respond to urbanization and if a habitat index can be used as an indirect measure of urban effects on stream ecosystems. We sampled 30 wadeable streams along an urban gradient (5?37% urban land cover) in the Etowah River basin, Georgia. Fish assemblages, sampled by electrofishing
Authors
D.M. Walters, Mary C. Freeman, D.S. Leigh, B. J. Freeman, C.P. Pringle
Status and conservation of the fish fauna of the Alabama River system
The Alabama River system, comprising the Alabama, Coosa, and Tallapoosa subsystems, forms the eastern portion of the Mobile River drainage. Physiographic diversity and geologic history have fostered development in the Alabama River system of globally significant levels of aquatic faunal diversity and endemism. At least 184 fishes are native to the system, including at least 33 endemic species.
Authors
Mary C. Freeman, E.R. Irwin, N.M. Burkhead, B. J. Freeman, H.L. Bart
Status and conservation of the fish fauna of the Alabama River system
The Alabama River system, comprising the Alabama, Coosa, and Tallapoosa subsystems, forms the eastern portion of the Mobile River drainage. Physiographic diversity and geologic history have fostered development in the Alabama River system of globally significant levels of aquatic faunal diversity and endemism. At least 184 fishes are native to the system, including at least 33 endemic species. Dur
Authors
Mary C. Freeman, E.R. Irwin, N.M. Burkhead, B. J. Freeman, H.L. Bart
Drought responses of freshwater mussels (Unionidae) in coastal plain tributaries of the Flint River basin, Georgia
During extreme drought conditions, mussel survival and habitat conditions were monitored weekly at nine locations representing a gradient in stream size in the lower Flint River basin, Georgia, USA. Cumulative unionid mortality ranged from 13 to 93% among sites, and was associated with low flow velocity (below 0.01 m/s) and dissolved oxygen concentrations below 5 mg/L. Species assemblages demons
Authors
P.M. Gagnon, S.W. Golladay, W.K. Michener, Mary C. Freeman
Ecosystem-level consequences of migratory faunal depletion caused by dams
Humans have been damming rivers for millennia, and our more ambitious efforts over the past century have arguably altered river ecosystems more extensively than any other anthropogenic activity. Effects of damming on river biota include decimation of migratory fauna (e.g., diadromous and potamodromous fishes and crustaceans), lost fisheries, and imperilment of obligate riverine taxa. Although ef
Authors
Mary C. Freeman, C. M. Pringle, E.A. Greathouse, B. J. Freeman
Effects of pulsed, high-velocity water flow on larval robust redhorse and V-lip redhorse
The pulsed, high-velocity water flow characteristic of water-flow patterns downstream from hydropower-generating dams has been implicated in the declining abundance of both aquatic insects and fishes in dam-regulated rivers. This study examined the effects of 0, 4, and 12 h per day of pulsed, high-velocity water flow on the egg mortality, hatch length, final length, and survival of larval robust r
Authors
R.S. Weyers, Cecil A. Jennings, Mary C. Freeman
Geomorphology and fish assemblages in a Piedmont river basin, U.S.A.
1. We investigated linkages between fishes and fluvial geomorphology in 31 wadeable streams in the Etowah River basin in northern Georgia, U.S.A. Streams were stratified into three catchment sizes of approximately 15, 50 and 100 km2, and fishes and geomorphology were sampled at the reach scale (i.e. 20–40 times stream width).2. Non-metric multidimensional scaling (NMDS) identified 85% of the among
Authors
D.M. Walters, D.S. Leigh, Mary C. Freeman, B. J. Freeman, C. M. Pringle
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Filter Total Items: 107
Analysis of spawning behavior, habitat, and season of the federally threatened Etheostoma scotti, Cherokee darter (Osteichthyes: Percidae)
Etheostoma scotti (Cherokee darter) is a member of the subgenus Ulocentra and a federally threatened endemic to the Etowah River system, GA. Field observations of spawning behavior of the Cherokee darter were made at five stream sites to identify spawning season and habitat over two field seasons. Cherokee darters primarily spawn in pool habitats between mid-March and early June, at temperaturesAuthorsC.M. Storey, B.A. Porter, Mary C. Freeman, B. J. FreemanImportance of riparian forests in urban catchments contingent on sediment and hydrologic regimes
Forested riparian corridors are thought to minimize impacts of landscape disturbance on stream ecosystems; yet, the effectiveness of streamside forests in mitigating disturbance in urbanizing catchments is unknown. We expected that riparian forests would provide minimal benefits for fish assemblages in streams that are highly impaired by sediment or hydrologic alteration. We tested this hypothesisAuthorsA.H. Roy, Mary C. Freeman, B. J. Freeman, S.J. Wenger, J.L. Meyer, W.E. EnsignFish-assemblage variation between geologically defined regions and across a longitudinal gradient in the Monkey River Basin, Belize
Linkages between geology and fish assemblages have been inferred in many regions throughout the world, but no studies have yet investigated whether fish assemblages differ across geologies in Mesoamerica. The goals of our study were to: 1) compare physicochemical conditions and fish-assemblage structure across 2 geologic types in headwaters of the Monkey River Basin, Belize, and 2) describe basin-AuthorsP.C. Esselman, Mary C. Freeman, C. M. PringleReach-scale effects of riparian forest cover on urban stream ecosystems
We compared habitat and biota between paired open and forested reaches within five small streams (basin area 10?20 km2) in suburban catchments (9%?49% urban land cover) in the Piedmont of Georgia, USA. Stream reaches with open canopies were narrower than forested reaches (4.1 versus 5.0 m, respectively). There were no differences in habitat diversity (variation in velocity, depth, or bed particlAuthorsA.H. Roy, C.L. Faust, Mary C. Freeman, J.L. MeyerInvestigating hydrologic alteration as a mechanism of fish assemblage shifts in urbanizing streams
Stream biota in urban and suburban settings are thought to be impaired by altered hydrology; however, it is unknown what aspects of the hydrograph alter fish assemblage structure and which fishes are most vulnerable to hydrologic alterations in small streams. We quantified hydrologic variables and fish assemblages in 30 small streams and their subcatchments (area 8–20 km2) in the Etowah River CatcAuthorsA.H. Roy, Mary C. Freeman, B. J. Freeman, S.J. Wenger, W.E. Ensign, J.L. MeyerUrbanization effects on fishes and habitat quality in a southern Piedmont river basin
We quantified the relationships among urban land cover, fishes, and habitat quality to determine how fish assemblages respond to urbanization and if a habitat index can be used as an indirect measure of urban effects on stream ecosystems. We sampled 30 wadeable streams along an urban gradient (5?37% urban land cover) in the Etowah River basin, Georgia. Fish assemblages, sampled by electrofishingAuthorsD.M. Walters, Mary C. Freeman, D.S. Leigh, B. J. Freeman, C.P. PringleStatus and conservation of the fish fauna of the Alabama River system
The Alabama River system, comprising the Alabama, Coosa, and Tallapoosa subsystems, forms the eastern portion of the Mobile River drainage. Physiographic diversity and geologic history have fostered development in the Alabama River system of globally significant levels of aquatic faunal diversity and endemism. At least 184 fishes are native to the system, including at least 33 endemic species.AuthorsMary C. Freeman, E.R. Irwin, N.M. Burkhead, B. J. Freeman, H.L. BartStatus and conservation of the fish fauna of the Alabama River system
The Alabama River system, comprising the Alabama, Coosa, and Tallapoosa subsystems, forms the eastern portion of the Mobile River drainage. Physiographic diversity and geologic history have fostered development in the Alabama River system of globally significant levels of aquatic faunal diversity and endemism. At least 184 fishes are native to the system, including at least 33 endemic species. DurAuthorsMary C. Freeman, E.R. Irwin, N.M. Burkhead, B. J. Freeman, H.L. BartDrought responses of freshwater mussels (Unionidae) in coastal plain tributaries of the Flint River basin, Georgia
During extreme drought conditions, mussel survival and habitat conditions were monitored weekly at nine locations representing a gradient in stream size in the lower Flint River basin, Georgia, USA. Cumulative unionid mortality ranged from 13 to 93% among sites, and was associated with low flow velocity (below 0.01 m/s) and dissolved oxygen concentrations below 5 mg/L. Species assemblages demonsAuthorsP.M. Gagnon, S.W. Golladay, W.K. Michener, Mary C. FreemanEcosystem-level consequences of migratory faunal depletion caused by dams
Humans have been damming rivers for millennia, and our more ambitious efforts over the past century have arguably altered river ecosystems more extensively than any other anthropogenic activity. Effects of damming on river biota include decimation of migratory fauna (e.g., diadromous and potamodromous fishes and crustaceans), lost fisheries, and imperilment of obligate riverine taxa. Although efAuthorsMary C. Freeman, C. M. Pringle, E.A. Greathouse, B. J. FreemanEffects of pulsed, high-velocity water flow on larval robust redhorse and V-lip redhorse
The pulsed, high-velocity water flow characteristic of water-flow patterns downstream from hydropower-generating dams has been implicated in the declining abundance of both aquatic insects and fishes in dam-regulated rivers. This study examined the effects of 0, 4, and 12 h per day of pulsed, high-velocity water flow on the egg mortality, hatch length, final length, and survival of larval robust rAuthorsR.S. Weyers, Cecil A. Jennings, Mary C. FreemanGeomorphology and fish assemblages in a Piedmont river basin, U.S.A.
1. We investigated linkages between fishes and fluvial geomorphology in 31 wadeable streams in the Etowah River basin in northern Georgia, U.S.A. Streams were stratified into three catchment sizes of approximately 15, 50 and 100 km2, and fishes and geomorphology were sampled at the reach scale (i.e. 20–40 times stream width).2. Non-metric multidimensional scaling (NMDS) identified 85% of the amongAuthorsD.M. Walters, D.S. Leigh, Mary C. Freeman, B. J. Freeman, C. M. Pringle