Bob Gresswell, Ph.D. (Former Employee)
Science and Products
FAQ on Invasive Lake Trout in Yellowstone Lake
These Frequently Asked Questions and responses were developed by USGS and their partners with the Lake Trout Suppression Scientific Review Panel *. The purpose of these FAQs is to provide answers to several of the more common questions concerning the lake trout suppression program in Yellowstone Lake, within Yellowstone National Park, and provide information about the current status of the program...
Predicting Effects of Climate Change on Native Fishes in Northern Great Plains Streams
The Northern Great Plains of North America are a region of profound global importance because organisms that live in these semi-arid prairie environments have developed a unique ability to live through conditions of extreme heat, cold, floods, and drought. Prairie streams are essential components of these ecosystems because they provide critical “green lines” of habitat for both aquatic and...
Estimating Future Streamflow in Eastern Montana Using the Precipitation-Runoff Modeling System and the RegCM3 Regional Climate Model
Streams in the Northern Great Plains provide critical “green lines” of habitat for aquatic and terrestrial wildlife. However, changes in water quantity associated with global climate change may transform some prairie streams from essential refuges to habitats no longer capable of supporting fishes. Although studies have examined climate change effects on larger river basins across the United...
Yellowstone Lake Acoustic Biotelemetry Project Home Page
Fishery biologists and managers are increasingly consumed with the recovery and restoration of native trout and salmon throughout the western United States. These fish historically inhabited a variety of freshwater habitats, but have declined due to habitat degradation, fragmentation and introduction of nonnative species. Introduced fishes constitute a major threat to the persistence of native...
Bob Gresswell's Past Projects
Bob Gresswell's Past Projects
Understanding Extreme Climate Events in the North Central U.S.
The climate of the North Central U.S. is driven by a combination of factors, including atmospheric circulation patterns, the region’s complex topography which extends from the High Rockies to the Great Plains, and variations in hydrology. Together, these factors determine the sustainability of the region’s ecosystems and the services that they provide communities. In order to understand...
The Potential Influence of Changing Climate on the Persistence of Native Salmonids
Understanding how climate change will influence habitat for interior species of native salmonids is critical for effective management and recovery of these species. The US Department of the Interior, the US Department of Agriculture, state fisheries managers, and non-governmental organizations are increasingly challenged in attempting the recovery and restoration of native trout and...
Filter Total Items: 78
Fish response to successive clearcuts in a second-growth forest from the central Coast range of Oregon
Research dating back to the 1950 s has documented negative effects from harvesting of primeval forests on stream ecosystems of the Pacific Northwest. By the early 1990 s, state and federal forest practice rules governing timber harvest were modified throughout North America to better protect aquatic habitats and biotic resources, principally salmonids. These rules inspired a generation...
Authors
D. S. Bateman, Nathan Chelgren, Robert E. Gresswell, Jason B. Dunham, David Hockman-Wert, D. W. Leer, Kevin D. Bladon
Invasive Lake Trout reproduction in Yellowstone Lake under an active suppression program
In Yellowstone Lake, predation by invasive Lake Trout Salvelinus namaycush has caused significant abundance declines in native Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri. Lake Trout suppression has been ongoing since 1995; assessment and simulation modeling are used to measure suppression effectiveness and guide efforts. Lake Trout reproduction demographics are linked to...
Authors
Nicholas A. Heredia, Robert E. Gresswell, Molly A.H. Webb, Travis O. Brenden, Philip T. Sandstrom
Carbon dioxide-induced mortality of four species of North American fishes
Fisheries managers have a growing interest in the use of carbon dioxide (CO2) as a tool for controlling invasive fishes. However, limited published data exist on susceptibility of many commonly encountered species to elevated CO2 concentrations. Our objective was to estimate the 24-h 50% lethal concentration (LC50) and 95% lethal concentration (LC95) of CO2 for four fishes (Rainbow Trout...
Authors
Hilary B. Treanor, Andrew M. Ray, Jon Amberg, Mark P. Gaikowski, Jason E. Ilgen, Robert E. Gresswell, Leslie Gains-Germain, Molly A.H. Webb
Yellowstone Lake ecosystem restoration: A case study for invasive fish management
Invasive predatory lake trout Salvelinus namaycush were discovered in Yellowstone Lake in 1994 and caused a precipitous decrease in abundance of native Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri. Suppression efforts (primarily gillnetting) initiated in 1995 did not curtail lake trout population growth or lakewide expansion. An adaptive management strategy was developed in...
Authors
Todd M . Koel, Jeffrey R. Arnold, Patricia E. Bigelow, Travis O. Brenden, Jeffery D. Davis, Colleen R. Detjens, Philip D. Doepke, Brian D. Ertel, Hayley Corrine Glassic, Robert E. Gresswell, Christopher S. Guy, Drew J. MacDonald, Michael E. Ruhl, Todd J. Stuth, David P. Sweet, John M. Syslo, Nathan A. Thomas, Lusha M. Tronstad, Patrick J. White, Alexander V. Zale
A call for global action to conserve native trout in the 21st century and beyond
Trout and char (hereafter, trout ) represent some of the more culturally, economically and ecologically important taxa of freshwater fishes worldwide (Kershner, Williams, Gresswell, & Lobón‐Cerviá, 2019a). Native to all continents in the Northern Hemisphere (as well as western Mediterranean Africa), trout belong to seven genera (Oncorhynchus , Salvelinus, Salmo , Hucho, Parahucho...
Authors
Daniel C. Dauwalter, Antonino Duchi, John Epifanio, A.J. Gandolfi, Robert E. Gresswell, Francis Juanes, Jeffrey L. Kershner, Javier Lobón-Cerviá, Philip McGinnity, Andreas Meraner, Pavel Mikheev, Kentaro Morita, Clint C. Muhlfeld, Kurt Pinter, John Post, Gunther Unfer, Leif Asbjorn Vollestad, Jack E. Williams
Revealing migration and reproductive habitat of invasive fish under an active population suppression program
Endemic species face a variety of threats including predation from non‐native invaders. In some cases, however, invasive species can be managed by directly suppressing populations, and tracking technologies that allow researchers to identify movement patterns and aggregations representative of the population can facilitate suppression activities. In Yellowstone Lake (Yellowstone National...
Authors
Lee Gutowsky, Jason G. Romine, Nicholas A. Heredia, Patricia E. Bigelow, Michael Parsley, Philip T. Sandstrom, Cory D. Suski, Andy J. Danylchuk, Steven J. Cooke, Robert E. Gresswell
Rapid early development and feeding benefits an invasive population of lake trout
Lake trout (Salvelinus namaycush) were discovered in Yellowstone Lake in 1994 and their population expanded dramatically despite intensive suppression. The lake is species-depauperate, with no major lake trout embryo predators. We hypothesized that without this predation threat, lake trout free embryo feeding and growth may be greater than in their native range, leading to increased...
Authors
Lee G. Simard, J. Ellen Marsden, Robert E. Gresswell, Megan Euclide
The effectiveness of non-native fish removal techniques in freshwater ecosystems: a systematic review
In aquatic systems, biological invasions can result in adverse ecological effects. Management techniques available for non-native fish removal programs (including eradication and population size control) vary widely, but include chemicals, harvest regimes, physical removal, or biological control. For management agencies, deciding on what non-native fish removal program to use has been...
Authors
Trina Rytwinski, Jessica J. Taylor, Lisa A. Donaldson, J. Robert Britton, David R. Browne, Robert E. Gresswell, Mark Lintermans, Kent A. Prior, Marlow G. Pellatt, Chantal Vis, Steven J. Cooke
Application of multistate modeling to estimate salmonid survival and movement in relation to spatial and temporal variation in metal exposure in a large mining-impacted river
We used telemetry and multistate modeling to estimate survival and movement of brown trout Salmo trutta and westslope cutthroat trout Oncorhynchus clarkii lewisi in relation to dissolved copper concentrations in 189 km of the upper Clark Fork River, Montana, a mining-impacted river in western Montana. Annual survival estimates for both brown trout (range, 0.27-0.53) and westslope...
Authors
Mariah P. Mayfield, Tom E McMahon, Jay J. Rotella, Robert E. Gresswell, Trevor M. Selch, Patrick Saffle, Jason Lindstrom, Brad Liermann
A portfolio framework for prioritizing conservation efforts for Yellowstone Cutthroat Trout populations
Managing and conserving native taxa are becoming increasingly challenging because of mounting threats and limited resources, predicating the need for frameworks to prioritize conservation actions. We integrated attributes of population persistence, genetic status, threats from nonnative species, and threats from climatic shifts to prioritize conservation actions for Yellowstone Cutthroat...
Authors
Robert K. Al-Chokhachy, Bradley B. Shepard, Jason C. Burckhardt, Dan Garren, Sebastian Opitz, Todd M . Koel, Lee M. Nelson, Robert E. Gresswell
Fish response to contemporary timber harvest practices in a second-growth forest from the central Coast Range of Oregon
We used a paired-watershed approach to investigate the effects of contemporary logging practices on headwater populations of coastal cutthroat trout (Oncorhynchus clarkii clarkii) and juvenile coho salmon (Oncorhynchus kisutch) in a second-growth Douglas-fir forested catchment in Oregon. Stream habitat and fish population characteristics, including biomass, abundance, growth, size, and...
Authors
Douglas S. Bateman, Robert E. Gresswell, Dana R. Warren, David Hockman-Wert, David W. Leer, Jeffrey T. Light, John D. Stednick
Using carbon dioxide in fisheries and aquatic invasive species management
To restore native fish populations, fisheries programs often depend on active removal of aquatic invasive species. Chemical removal can be an effective method of eliminating aquatic invasive species, but chemicals can induce mortality in nontarget organisms and persist in the environment. Carbon dioxide (CO2) is an emerging alternative to traditional chemical control agents because it...
Authors
Hilary B. Treanor, Andrew M. Ray, Megan J. Layhee, Barnaby J. Watten, Jason A. Gross, Robert E. Gresswell, Molly A.H. Webb
Science and Products
FAQ on Invasive Lake Trout in Yellowstone Lake
These Frequently Asked Questions and responses were developed by USGS and their partners with the Lake Trout Suppression Scientific Review Panel *. The purpose of these FAQs is to provide answers to several of the more common questions concerning the lake trout suppression program in Yellowstone Lake, within Yellowstone National Park, and provide information about the current status of the program...
Predicting Effects of Climate Change on Native Fishes in Northern Great Plains Streams
The Northern Great Plains of North America are a region of profound global importance because organisms that live in these semi-arid prairie environments have developed a unique ability to live through conditions of extreme heat, cold, floods, and drought. Prairie streams are essential components of these ecosystems because they provide critical “green lines” of habitat for both aquatic and...
Estimating Future Streamflow in Eastern Montana Using the Precipitation-Runoff Modeling System and the RegCM3 Regional Climate Model
Streams in the Northern Great Plains provide critical “green lines” of habitat for aquatic and terrestrial wildlife. However, changes in water quantity associated with global climate change may transform some prairie streams from essential refuges to habitats no longer capable of supporting fishes. Although studies have examined climate change effects on larger river basins across the United...
Yellowstone Lake Acoustic Biotelemetry Project Home Page
Fishery biologists and managers are increasingly consumed with the recovery and restoration of native trout and salmon throughout the western United States. These fish historically inhabited a variety of freshwater habitats, but have declined due to habitat degradation, fragmentation and introduction of nonnative species. Introduced fishes constitute a major threat to the persistence of native...
Bob Gresswell's Past Projects
Bob Gresswell's Past Projects
Understanding Extreme Climate Events in the North Central U.S.
The climate of the North Central U.S. is driven by a combination of factors, including atmospheric circulation patterns, the region’s complex topography which extends from the High Rockies to the Great Plains, and variations in hydrology. Together, these factors determine the sustainability of the region’s ecosystems and the services that they provide communities. In order to understand...
The Potential Influence of Changing Climate on the Persistence of Native Salmonids
Understanding how climate change will influence habitat for interior species of native salmonids is critical for effective management and recovery of these species. The US Department of the Interior, the US Department of Agriculture, state fisheries managers, and non-governmental organizations are increasingly challenged in attempting the recovery and restoration of native trout and...
Filter Total Items: 78
Fish response to successive clearcuts in a second-growth forest from the central Coast range of Oregon
Research dating back to the 1950 s has documented negative effects from harvesting of primeval forests on stream ecosystems of the Pacific Northwest. By the early 1990 s, state and federal forest practice rules governing timber harvest were modified throughout North America to better protect aquatic habitats and biotic resources, principally salmonids. These rules inspired a generation...
Authors
D. S. Bateman, Nathan Chelgren, Robert E. Gresswell, Jason B. Dunham, David Hockman-Wert, D. W. Leer, Kevin D. Bladon
Invasive Lake Trout reproduction in Yellowstone Lake under an active suppression program
In Yellowstone Lake, predation by invasive Lake Trout Salvelinus namaycush has caused significant abundance declines in native Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri. Lake Trout suppression has been ongoing since 1995; assessment and simulation modeling are used to measure suppression effectiveness and guide efforts. Lake Trout reproduction demographics are linked to...
Authors
Nicholas A. Heredia, Robert E. Gresswell, Molly A.H. Webb, Travis O. Brenden, Philip T. Sandstrom
Carbon dioxide-induced mortality of four species of North American fishes
Fisheries managers have a growing interest in the use of carbon dioxide (CO2) as a tool for controlling invasive fishes. However, limited published data exist on susceptibility of many commonly encountered species to elevated CO2 concentrations. Our objective was to estimate the 24-h 50% lethal concentration (LC50) and 95% lethal concentration (LC95) of CO2 for four fishes (Rainbow Trout...
Authors
Hilary B. Treanor, Andrew M. Ray, Jon Amberg, Mark P. Gaikowski, Jason E. Ilgen, Robert E. Gresswell, Leslie Gains-Germain, Molly A.H. Webb
Yellowstone Lake ecosystem restoration: A case study for invasive fish management
Invasive predatory lake trout Salvelinus namaycush were discovered in Yellowstone Lake in 1994 and caused a precipitous decrease in abundance of native Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri. Suppression efforts (primarily gillnetting) initiated in 1995 did not curtail lake trout population growth or lakewide expansion. An adaptive management strategy was developed in...
Authors
Todd M . Koel, Jeffrey R. Arnold, Patricia E. Bigelow, Travis O. Brenden, Jeffery D. Davis, Colleen R. Detjens, Philip D. Doepke, Brian D. Ertel, Hayley Corrine Glassic, Robert E. Gresswell, Christopher S. Guy, Drew J. MacDonald, Michael E. Ruhl, Todd J. Stuth, David P. Sweet, John M. Syslo, Nathan A. Thomas, Lusha M. Tronstad, Patrick J. White, Alexander V. Zale
A call for global action to conserve native trout in the 21st century and beyond
Trout and char (hereafter, trout ) represent some of the more culturally, economically and ecologically important taxa of freshwater fishes worldwide (Kershner, Williams, Gresswell, & Lobón‐Cerviá, 2019a). Native to all continents in the Northern Hemisphere (as well as western Mediterranean Africa), trout belong to seven genera (Oncorhynchus , Salvelinus, Salmo , Hucho, Parahucho...
Authors
Daniel C. Dauwalter, Antonino Duchi, John Epifanio, A.J. Gandolfi, Robert E. Gresswell, Francis Juanes, Jeffrey L. Kershner, Javier Lobón-Cerviá, Philip McGinnity, Andreas Meraner, Pavel Mikheev, Kentaro Morita, Clint C. Muhlfeld, Kurt Pinter, John Post, Gunther Unfer, Leif Asbjorn Vollestad, Jack E. Williams
Revealing migration and reproductive habitat of invasive fish under an active population suppression program
Endemic species face a variety of threats including predation from non‐native invaders. In some cases, however, invasive species can be managed by directly suppressing populations, and tracking technologies that allow researchers to identify movement patterns and aggregations representative of the population can facilitate suppression activities. In Yellowstone Lake (Yellowstone National...
Authors
Lee Gutowsky, Jason G. Romine, Nicholas A. Heredia, Patricia E. Bigelow, Michael Parsley, Philip T. Sandstrom, Cory D. Suski, Andy J. Danylchuk, Steven J. Cooke, Robert E. Gresswell
Rapid early development and feeding benefits an invasive population of lake trout
Lake trout (Salvelinus namaycush) were discovered in Yellowstone Lake in 1994 and their population expanded dramatically despite intensive suppression. The lake is species-depauperate, with no major lake trout embryo predators. We hypothesized that without this predation threat, lake trout free embryo feeding and growth may be greater than in their native range, leading to increased...
Authors
Lee G. Simard, J. Ellen Marsden, Robert E. Gresswell, Megan Euclide
The effectiveness of non-native fish removal techniques in freshwater ecosystems: a systematic review
In aquatic systems, biological invasions can result in adverse ecological effects. Management techniques available for non-native fish removal programs (including eradication and population size control) vary widely, but include chemicals, harvest regimes, physical removal, or biological control. For management agencies, deciding on what non-native fish removal program to use has been...
Authors
Trina Rytwinski, Jessica J. Taylor, Lisa A. Donaldson, J. Robert Britton, David R. Browne, Robert E. Gresswell, Mark Lintermans, Kent A. Prior, Marlow G. Pellatt, Chantal Vis, Steven J. Cooke
Application of multistate modeling to estimate salmonid survival and movement in relation to spatial and temporal variation in metal exposure in a large mining-impacted river
We used telemetry and multistate modeling to estimate survival and movement of brown trout Salmo trutta and westslope cutthroat trout Oncorhynchus clarkii lewisi in relation to dissolved copper concentrations in 189 km of the upper Clark Fork River, Montana, a mining-impacted river in western Montana. Annual survival estimates for both brown trout (range, 0.27-0.53) and westslope...
Authors
Mariah P. Mayfield, Tom E McMahon, Jay J. Rotella, Robert E. Gresswell, Trevor M. Selch, Patrick Saffle, Jason Lindstrom, Brad Liermann
A portfolio framework for prioritizing conservation efforts for Yellowstone Cutthroat Trout populations
Managing and conserving native taxa are becoming increasingly challenging because of mounting threats and limited resources, predicating the need for frameworks to prioritize conservation actions. We integrated attributes of population persistence, genetic status, threats from nonnative species, and threats from climatic shifts to prioritize conservation actions for Yellowstone Cutthroat...
Authors
Robert K. Al-Chokhachy, Bradley B. Shepard, Jason C. Burckhardt, Dan Garren, Sebastian Opitz, Todd M . Koel, Lee M. Nelson, Robert E. Gresswell
Fish response to contemporary timber harvest practices in a second-growth forest from the central Coast Range of Oregon
We used a paired-watershed approach to investigate the effects of contemporary logging practices on headwater populations of coastal cutthroat trout (Oncorhynchus clarkii clarkii) and juvenile coho salmon (Oncorhynchus kisutch) in a second-growth Douglas-fir forested catchment in Oregon. Stream habitat and fish population characteristics, including biomass, abundance, growth, size, and...
Authors
Douglas S. Bateman, Robert E. Gresswell, Dana R. Warren, David Hockman-Wert, David W. Leer, Jeffrey T. Light, John D. Stednick
Using carbon dioxide in fisheries and aquatic invasive species management
To restore native fish populations, fisheries programs often depend on active removal of aquatic invasive species. Chemical removal can be an effective method of eliminating aquatic invasive species, but chemicals can induce mortality in nontarget organisms and persist in the environment. Carbon dioxide (CO2) is an emerging alternative to traditional chemical control agents because it...
Authors
Hilary B. Treanor, Andrew M. Ray, Megan J. Layhee, Barnaby J. Watten, Jason A. Gross, Robert E. Gresswell, Molly A.H. Webb