Bob Gresswell, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 60
Life history migrations of adult Yellowstone Cutthroat Trout in the upper Yellowstone River
Knowledge of salmonid life history types at the watershed scale is increasingly recognized as a cornerstone for effective management. In this study, we used radiotelemetry to characterize the life history movements of Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri in the upper Yellowstone River, an extensive tributary that composes nearly half of the drainage area of Yellowstone Lake. I
Authors
Brian D. Ertel, Thomas E. McMahon, Todd M. Koel, Robert E. Gresswell, Jason Burckhardt
Identifying movement patterns and spawning areas of Lake Trout in Yellowstone Lake
No abstract available.
Authors
Robert E. Gresswell, Nicholas A. Heredia, Jason G. Romine, Lee F. G. Gutowsky, Phillip T. Sandstrom, Michael J. Parsley, Patricia E. Bigelow, C. D. Suski, Brian D. Ertel
Early detection of nonnative alleles in fish populations: When sample size actually matters
Reliable detection of nonnative alleles is crucial for the conservation of sensitive native fish populations at risk of introgression. Typically, nonnative alleles in a population are detected through the analysis of genetic markers in a sample of individuals. Here we show that common assumptions associated with such analyses yield substantial overestimates of the likelihood of detecting nonnative
Authors
Patrick Della Croce, Geoffrey C. Poole, Robert A. Payne, Robert E. Gresswell
The waterfall paradox: How knickpoints disconnect hillslope and channel processes, isolating salmonid populations in ideal habitats
Waterfalls create barriers to fish migration, yet hundreds of isolated salmonid populations exist above barriers and have persisted for thousands of years in steep mountainous terrain. Ecological theory indicates that small isolated populations in disturbance-prone landscapes are at greatest risk of extirpation because immigration and recolonization are not possible. On the contrary, many above-ba
Authors
Christine May, Joshua J. Roering, Kyle Snow, Kitty Griswold, Robert E. Gresswell
Effects of stream-adjacent logging in fishless headwaters on downstream coastal cutthroat trout
To investigate effects of headwater logging on downstream coastal cutthroat trout (Oncorhynchus clarkii clarkii) populations, we monitored stream habitat and biotic indicators including biomass, abundance, growth, movement, and survival over 8 years using a paired-watershed approach. Reference and logged catchments were located on private industrial forestland on ∼60-year harvest rotation. Five cl
Authors
Douglas S. Bateman, Matthew R. Sloat, Robert E. Gresswell, Aaron M. Berger, David Hockman-Wert, David W. Leer, Arne E. Skaugset
Conservation of native Pacific trout diversity in western North America
Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review the state of knowledge on these important issues, f
Authors
Brooke E. Penaluna, Alicia Abadía-Cardoso, Jason B. Dunham, Francisco J García de León, Robert E. Gresswell, Arturo Ruiz Luna, Eric B. Taylor, Bradley B. Shepard, Robert K. Al-Chokhachy, Clint C. Muhlfeld, Kevin R. Bestgen, Kevin H. Rogers, Marco A Escalante, Ernest R. Keeley, Gabriel Temple, Jack E. Williams, Kathleen Matthews, Ron Pierce, Richard L. Mayden, Ryan Kovach, John Carlos Garza, Kurt D. Fausch
Spawning and rearing behavior of bull trout in a headwater lake ecosystem
Numerous life histories have been documented for bull trout Salvelinus confluentus. Lacustrine-adfluvial bull trout populations that occupy small, headwater lake ecosystems and migrate short distances to natal tributaries to spawn are likely common; however, much of the research on potamodromous bull trout has focused on describing the spawning and rearing characteristics of bull trout populations
Authors
Lora B. Tennant, Robert E. Gresswell, Christopher S. Guy, Michael H. Meeuwig
Predicting spatial distribution of postfire debris flows and potential consequences for native trout in headwater streams
Habitat fragmentation and degradation and invasion of nonnative species have restricted the distribution of native trout. Many trout populations are limited to headwater streams where negative effects of predicted climate change, including reduced stream flow and increased risk of catastrophic fires, may further jeopardize their persistence. Headwater streams in steep terrain are especially suscep
Authors
Edwin R Sedell, Robert E. Gresswell, Thomas E. McMahon
Fire effects on aquatic ecosystems: an assessment of the current state of the science
Fire is a prevalent feature of many landscapes and has numerous and complex effects on geological, hydrological, ecological, and economic systems. In some regions, the frequency and intensity of wildfire have increased in recent years and are projected to escalate with predicted climatic and landuse changes. In addition, prescribed burns continue to be used in many parts of the world to clear vege
Authors
Rebecca J. Bixby, Scott D. Cooper, Robert E. Gresswell, Lee E. Brown, Clifford N. Dahm, Clifford N. Dahm, Kathleen A. Dwire
Life history diversity of Snake River finespotted cutthroat trout: managing for persistence in a rapidly changing environment
Over the last century, native trout have experienced dramatic population declines, particularly in larger river systems where habitats associated with different spawning life history forms have been lost through habitat degradation and fragmentation. The resulting decrease in life history diversity has affected the capacity of populations to respond to environmental variability and disturbance. Un
Authors
Kristen M. Homel, Robert E. Gresswell, Jeffrey L. Kershner
Quantifying stream thermal regimes at management-pertinent scales: combining thermal infrared and stationary stream temperature data in a novel modeling framework.
Accurately quantifying stream thermal regimes can be challenging because stream temperatures are often spatially and temporally heterogeneous. In this study, we present a novel modeling framework that combines stream temperature data sets that are continuous in either space or time. Specifically, we merged the fine spatial resolution of thermal infrared (TIR) imagery with hourly data from 10 stati
Authors
Shane J. Vatland, Robert E. Gresswell, Geoffrey C. Poole
Science and Products
Filter Total Items: 60
Life history migrations of adult Yellowstone Cutthroat Trout in the upper Yellowstone River
Knowledge of salmonid life history types at the watershed scale is increasingly recognized as a cornerstone for effective management. In this study, we used radiotelemetry to characterize the life history movements of Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri in the upper Yellowstone River, an extensive tributary that composes nearly half of the drainage area of Yellowstone Lake. I
Authors
Brian D. Ertel, Thomas E. McMahon, Todd M. Koel, Robert E. Gresswell, Jason Burckhardt
Identifying movement patterns and spawning areas of Lake Trout in Yellowstone Lake
No abstract available.
Authors
Robert E. Gresswell, Nicholas A. Heredia, Jason G. Romine, Lee F. G. Gutowsky, Phillip T. Sandstrom, Michael J. Parsley, Patricia E. Bigelow, C. D. Suski, Brian D. Ertel
Early detection of nonnative alleles in fish populations: When sample size actually matters
Reliable detection of nonnative alleles is crucial for the conservation of sensitive native fish populations at risk of introgression. Typically, nonnative alleles in a population are detected through the analysis of genetic markers in a sample of individuals. Here we show that common assumptions associated with such analyses yield substantial overestimates of the likelihood of detecting nonnative
Authors
Patrick Della Croce, Geoffrey C. Poole, Robert A. Payne, Robert E. Gresswell
The waterfall paradox: How knickpoints disconnect hillslope and channel processes, isolating salmonid populations in ideal habitats
Waterfalls create barriers to fish migration, yet hundreds of isolated salmonid populations exist above barriers and have persisted for thousands of years in steep mountainous terrain. Ecological theory indicates that small isolated populations in disturbance-prone landscapes are at greatest risk of extirpation because immigration and recolonization are not possible. On the contrary, many above-ba
Authors
Christine May, Joshua J. Roering, Kyle Snow, Kitty Griswold, Robert E. Gresswell
Effects of stream-adjacent logging in fishless headwaters on downstream coastal cutthroat trout
To investigate effects of headwater logging on downstream coastal cutthroat trout (Oncorhynchus clarkii clarkii) populations, we monitored stream habitat and biotic indicators including biomass, abundance, growth, movement, and survival over 8 years using a paired-watershed approach. Reference and logged catchments were located on private industrial forestland on ∼60-year harvest rotation. Five cl
Authors
Douglas S. Bateman, Matthew R. Sloat, Robert E. Gresswell, Aaron M. Berger, David Hockman-Wert, David W. Leer, Arne E. Skaugset
Conservation of native Pacific trout diversity in western North America
Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review the state of knowledge on these important issues, f
Authors
Brooke E. Penaluna, Alicia Abadía-Cardoso, Jason B. Dunham, Francisco J García de León, Robert E. Gresswell, Arturo Ruiz Luna, Eric B. Taylor, Bradley B. Shepard, Robert K. Al-Chokhachy, Clint C. Muhlfeld, Kevin R. Bestgen, Kevin H. Rogers, Marco A Escalante, Ernest R. Keeley, Gabriel Temple, Jack E. Williams, Kathleen Matthews, Ron Pierce, Richard L. Mayden, Ryan Kovach, John Carlos Garza, Kurt D. Fausch
Spawning and rearing behavior of bull trout in a headwater lake ecosystem
Numerous life histories have been documented for bull trout Salvelinus confluentus. Lacustrine-adfluvial bull trout populations that occupy small, headwater lake ecosystems and migrate short distances to natal tributaries to spawn are likely common; however, much of the research on potamodromous bull trout has focused on describing the spawning and rearing characteristics of bull trout populations
Authors
Lora B. Tennant, Robert E. Gresswell, Christopher S. Guy, Michael H. Meeuwig
Predicting spatial distribution of postfire debris flows and potential consequences for native trout in headwater streams
Habitat fragmentation and degradation and invasion of nonnative species have restricted the distribution of native trout. Many trout populations are limited to headwater streams where negative effects of predicted climate change, including reduced stream flow and increased risk of catastrophic fires, may further jeopardize their persistence. Headwater streams in steep terrain are especially suscep
Authors
Edwin R Sedell, Robert E. Gresswell, Thomas E. McMahon
Fire effects on aquatic ecosystems: an assessment of the current state of the science
Fire is a prevalent feature of many landscapes and has numerous and complex effects on geological, hydrological, ecological, and economic systems. In some regions, the frequency and intensity of wildfire have increased in recent years and are projected to escalate with predicted climatic and landuse changes. In addition, prescribed burns continue to be used in many parts of the world to clear vege
Authors
Rebecca J. Bixby, Scott D. Cooper, Robert E. Gresswell, Lee E. Brown, Clifford N. Dahm, Clifford N. Dahm, Kathleen A. Dwire
Life history diversity of Snake River finespotted cutthroat trout: managing for persistence in a rapidly changing environment
Over the last century, native trout have experienced dramatic population declines, particularly in larger river systems where habitats associated with different spawning life history forms have been lost through habitat degradation and fragmentation. The resulting decrease in life history diversity has affected the capacity of populations to respond to environmental variability and disturbance. Un
Authors
Kristen M. Homel, Robert E. Gresswell, Jeffrey L. Kershner
Quantifying stream thermal regimes at management-pertinent scales: combining thermal infrared and stationary stream temperature data in a novel modeling framework.
Accurately quantifying stream thermal regimes can be challenging because stream temperatures are often spatially and temporally heterogeneous. In this study, we present a novel modeling framework that combines stream temperature data sets that are continuous in either space or time. Specifically, we merged the fine spatial resolution of thermal infrared (TIR) imagery with hourly data from 10 stati
Authors
Shane J. Vatland, Robert E. Gresswell, Geoffrey C. Poole