Bob Gresswell, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 78
Twenty Years After the 1988 Yellowstone Fires: Lessons About Disturbance and Ecosystems Twenty Years After the 1988 Yellowstone Fires: Lessons About Disturbance and Ecosystems
The 1988 Yellowstone fires were among the first in what has proven to be an upsurge in large severe fires in the western USA during the past 20 years. At the time of the fires, little was known about the impacts of such a large severe disturbance because scientists had had few previous opportunities to study such an event. Ecologists predicted short- and long-term effects of the 1988...
Authors
W.H. Romme, M.S. Boyce, R. Gresswell, E.H. Merrill, G.W. Minshall, C. Whitlock, M.G. Turner
The potential influence of changing climate on the persistence of salmonids of the inland west The potential influence of changing climate on the persistence of salmonids of the inland west
The Earth's climate warmed steadily during the 20th century, and mean annual air temperatures are estimated to have increased by 0.6°C (Intergovernmental Panel on Climate Change, 2007). Although many cycles of warming and cooling have occurred in the past, the most recent warming period is unique in its rate and magnitude of change (Siegenthaler and others, 2005) and in its association...
Authors
A.L. Haak, J.E. Williams, D. Isaak, A. Todd, C.C. Muhlfeld, J. L. Kershner, R. E. Gresswell, S. W. Hostetler, H.M. Neville
Factors influencing coastal cutthroat trout (Oncorhynchus clarkii clarkii) seasonal survival rates: A spatially continuous approach within stream networks Factors influencing coastal cutthroat trout (Oncorhynchus clarkii clarkii) seasonal survival rates: A spatially continuous approach within stream networks
Mark-recapture methods were used to examine watershed-scale survival of coastal cutthroat trout (Oncorhynchus clarkii clarkii) from two headwater stream networks. A total of 1725 individuals (???100 mm, fork length) were individually marked and monitored seasonally over a 3-year period. Differences in survival were compared among spatial (stream segment, subwatershed, and watershed) and...
Authors
A.M. Berger, R. E. Gresswell
Landscape-scale evaluation of genetic structure among barrier-isolated populations of coastal cutthroat trout, Oncorhynchus clarkii clarkii Landscape-scale evaluation of genetic structure among barrier-isolated populations of coastal cutthroat trout, Oncorhynchus clarkii clarkii
Relationships among landscape structure, stochastic disturbance, and genetic diversity were assessed by examining interactions between watershed-scale environmental factors and genetic diversity of coastal cutthroat trout (Oncorhynchus clarkii clarkii) in 27 barrier-isolated watersheds from western Oregon, USA. Headwater populations of coastal cutthroat trout were genetically...
Authors
T.J. Guy, R. E. Gresswell, M. A. Banks
Longitudinal patterns of fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River, Oregon Longitudinal patterns of fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River, Oregon
The Lower Crooked River is a remarkable groundwater-fed stream flowing through vertical basalt canyons in the Deschutes River Valley ecoregion in central Oregon (Pater and others, 1998). The 9-mile section of the river between the Crooked River National Grasslands boundary near Ogden Wayside and river mile (RM) 8 is protected under the National Wild and Scenic Rivers Act (16 U.S.C. 1271...
Authors
Christian E. Torgersen, David P. Hockman-Wert, Douglas S. Bateman, David W. Leer, Robert E. Gresswell
Population-scale movement of coastal cutthroat trout in a naturally isolated stream network Population-scale movement of coastal cutthroat trout in a naturally isolated stream network
To identify population‐scale patterns of movement, coastal cutthroat trout Oncorhynchus clarkii clarkii tagged and marked (35 radio‐tagged, 749 passive integrated transponder [PIT]‐tagged, and 3,025 fin‐clipped) were monitored from June 1999 to August 2000. The study watershed, located in western Oregon, was above a natural barrier to upstream movement. Emigration out of the watershed...
Authors
R. E. Gresswell, S.R. Hendricks
Science and Products
Filter Total Items: 78
Twenty Years After the 1988 Yellowstone Fires: Lessons About Disturbance and Ecosystems Twenty Years After the 1988 Yellowstone Fires: Lessons About Disturbance and Ecosystems
The 1988 Yellowstone fires were among the first in what has proven to be an upsurge in large severe fires in the western USA during the past 20 years. At the time of the fires, little was known about the impacts of such a large severe disturbance because scientists had had few previous opportunities to study such an event. Ecologists predicted short- and long-term effects of the 1988...
Authors
W.H. Romme, M.S. Boyce, R. Gresswell, E.H. Merrill, G.W. Minshall, C. Whitlock, M.G. Turner
The potential influence of changing climate on the persistence of salmonids of the inland west The potential influence of changing climate on the persistence of salmonids of the inland west
The Earth's climate warmed steadily during the 20th century, and mean annual air temperatures are estimated to have increased by 0.6°C (Intergovernmental Panel on Climate Change, 2007). Although many cycles of warming and cooling have occurred in the past, the most recent warming period is unique in its rate and magnitude of change (Siegenthaler and others, 2005) and in its association...
Authors
A.L. Haak, J.E. Williams, D. Isaak, A. Todd, C.C. Muhlfeld, J. L. Kershner, R. E. Gresswell, S. W. Hostetler, H.M. Neville
Factors influencing coastal cutthroat trout (Oncorhynchus clarkii clarkii) seasonal survival rates: A spatially continuous approach within stream networks Factors influencing coastal cutthroat trout (Oncorhynchus clarkii clarkii) seasonal survival rates: A spatially continuous approach within stream networks
Mark-recapture methods were used to examine watershed-scale survival of coastal cutthroat trout (Oncorhynchus clarkii clarkii) from two headwater stream networks. A total of 1725 individuals (???100 mm, fork length) were individually marked and monitored seasonally over a 3-year period. Differences in survival were compared among spatial (stream segment, subwatershed, and watershed) and...
Authors
A.M. Berger, R. E. Gresswell
Landscape-scale evaluation of genetic structure among barrier-isolated populations of coastal cutthroat trout, Oncorhynchus clarkii clarkii Landscape-scale evaluation of genetic structure among barrier-isolated populations of coastal cutthroat trout, Oncorhynchus clarkii clarkii
Relationships among landscape structure, stochastic disturbance, and genetic diversity were assessed by examining interactions between watershed-scale environmental factors and genetic diversity of coastal cutthroat trout (Oncorhynchus clarkii clarkii) in 27 barrier-isolated watersheds from western Oregon, USA. Headwater populations of coastal cutthroat trout were genetically...
Authors
T.J. Guy, R. E. Gresswell, M. A. Banks
Longitudinal patterns of fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River, Oregon Longitudinal patterns of fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River, Oregon
The Lower Crooked River is a remarkable groundwater-fed stream flowing through vertical basalt canyons in the Deschutes River Valley ecoregion in central Oregon (Pater and others, 1998). The 9-mile section of the river between the Crooked River National Grasslands boundary near Ogden Wayside and river mile (RM) 8 is protected under the National Wild and Scenic Rivers Act (16 U.S.C. 1271...
Authors
Christian E. Torgersen, David P. Hockman-Wert, Douglas S. Bateman, David W. Leer, Robert E. Gresswell
Population-scale movement of coastal cutthroat trout in a naturally isolated stream network Population-scale movement of coastal cutthroat trout in a naturally isolated stream network
To identify population‐scale patterns of movement, coastal cutthroat trout Oncorhynchus clarkii clarkii tagged and marked (35 radio‐tagged, 749 passive integrated transponder [PIT]‐tagged, and 3,025 fin‐clipped) were monitored from June 1999 to August 2000. The study watershed, located in western Oregon, was above a natural barrier to upstream movement. Emigration out of the watershed...
Authors
R. E. Gresswell, S.R. Hendricks