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Bradley Bickford

Brad works for the Western Fisheries Research Center, Columbia River Research Laboratory, Clarkston Duty Station.

Science and Products

boat on Salmon River boat on Salmon River
Salmon River Redd Surveys
boat on Salmon River

Salmon River Redd Surveys

Salmon River Redd Surveys

This mesmerizing video, recorded by Tobyn N. Rhodes, is from USGS Western Fisheries Research Center’s field work on the lower Salmon River this past Fall 2025. Partnering with the Nez Perce Tribe, Rhodes and his team were counting the number of fall Chinook salmon nests, known as redds, with a drone piloted from a jet boat.

By
Ecosystems Mission Area
boat on Salmon River

Salmon River Redd Surveys

Salmon River Redd Surveys

This mesmerizing video, recorded by Tobyn N. Rhodes, is from USGS Western Fisheries Research Center’s field work on the lower Salmon River this past Fall 2025. Partnering with the Nez Perce Tribe, Rhodes and his team were counting the number of fall Chinook salmon nests, known as redds, with a drone piloted from a jet boat.

By
Ecosystems Mission Area
Scientist measuring a Fall Chinook salmon
Scientist measuring a Fall Chinook salmon captured in the Snake River
Scientist measuring a Fall Chinook salmon captured in the Snake River
Scientist measuring a Fall Chinook salmon

Scientist measuring a Fall Chinook salmon captured in the Snake River

Scientist measuring a Fall Chinook salmon captured in the Snake River

USGS scientist Dalton Lebeda is measuring a Fall Chinook salmon captured in the Snake River. This study is being conducted to determine the percentages of natural and hatchery origin spawners in the upper reach of Hells Canyon.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Scientist measuring a Fall Chinook salmon

Scientist measuring a Fall Chinook salmon captured in the Snake River

Scientist measuring a Fall Chinook salmon captured in the Snake River

USGS scientist Dalton Lebeda is measuring a Fall Chinook salmon captured in the Snake River. This study is being conducted to determine the percentages of natural and hatchery origin spawners in the upper reach of Hells Canyon.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Picture taken with a sUAS (drone) of Hells Canyon
Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023
Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023
Picture taken with a sUAS (drone) of Hells Canyon

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023. In the bottom of the picture, you can see one of our USGS work boats pulled onto shore. USGS scientists are conducting redd surveys for spawning Fall Chinook salmon.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Picture taken with a sUAS (drone) of Hells Canyon

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023. In the bottom of the picture, you can see one of our USGS work boats pulled onto shore. USGS scientists are conducting redd surveys for spawning Fall Chinook salmon.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Filter Total Items: 14

Snake River Fall Chinook Salmon research and monitoring Snake River Fall Chinook Salmon research and monitoring

In Chapter 1, we report on development and application of an integrated population model (IPM) for the natural-origin fall Chinook salmon population upstream of Lower Granite Dam. This year’s efforts represent the third update to the model. Initial efforts focused on generating juvenile and adult abundance estimates, with estimates of uncertainty, for informing the life-cycle model and
Authors
Russell W. Perry, Dalton Hance, John Plumb, Kenneth F. Tiffan, Brad Bickford, Scott Louis Benson, Tobyn Rhodes, Steve Brink, Brad Alcorn
By
Ecosystems Mission Area, Western Fisheries Research Center

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River Fall Chinook salmon ESU Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River Fall Chinook salmon ESU

The portion of the Snake River fall Chinook salmon Oncorhynchus tshawytscha evolutionary significant unit (ESU) that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2020 in response to U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on changes in population abundance and habitat use by...
Authors
Kenneth Tiffan, Peter H. Barry, Dalton Hance, John Plumb, Brad Bickford, Tobyn Rhodes, Dalton Dirk Lebeda, Rulon J. Hemingway, Kenneth G. King, John Hargrove
By
Ecosystems Mission Area, Western Fisheries Research Center

Performance of subyearling fall Chinook salmon tagged with 8‐, 9‐, and 12‐mm passive integrated transponder tags in the Snake River Performance of subyearling fall Chinook salmon tagged with 8‐, 9‐, and 12‐mm passive integrated transponder tags in the Snake River

Inferences based on tagged individuals from a population are limited in part by the minimum size of fish that can be tagged. Smaller tags allow a greater proportion of a population to be represented by tagging and should reduce potential tag effects on fish performance. We evaluated different performance metrics of juvenile fall Chinook Salmon Oncorhynchus tshawytscha tagged with 8‐, 9‐...
Authors
Kenneth F. Tiffan, Tobyn Rhodes, Brad Bickford, Dalton Dirk Lebeda, William P. Connor, Frank L. Mullins
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Impact of smallmouth bass predation on subyearling fall Chinook salmon over a broad river continuum Impact of smallmouth bass predation on subyearling fall Chinook salmon over a broad river continuum

Smallmouth bass (Micropterus dolomieu) predation on subyearling fall Chinook salmon (Oncorhynchus tshawytscha) was examined in the Snake River (USA) to identify seasonal and habitat-related changes in bass diets, and associated subyearling consumption and loss in various riverine and impounded reaches. Smallmouth bass diets reflected opportunistic foraging that at times showed predation...
Authors
Kenneth F. Tiffan, John M Erhardt, Rulon J. Hemingway, Brad Bickford, Tobyn Rhodes
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook Salmon ESU Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook Salmon ESU

The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2018 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners...
Authors
Kenneth F. Tiffan, Russell W. Perry, John Plumb, Dalton Hance, Brad Bickford, Tobyn Rhodes
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Fall Chinook salmon (Oncorhynchus tshawytscha), sand roller (Percopsis transmontana), and smallmouth bass (Micropterus dolomieu) interactions in a Snake River reservoir: A tale of three species Fall Chinook salmon (Oncorhynchus tshawytscha), sand roller (Percopsis transmontana), and smallmouth bass (Micropterus dolomieu) interactions in a Snake River reservoir: A tale of three species

We studied some of the relationships between federally listed fall Chinook Salmon, Oncorhynchus tshawytscha, endemic Sand Roller, Percopsis transmontana, and non-native Smallmouth Bass, Micropterus dolomieu, in Lower Granite Reservoir on the Snake River. Because of its recent reappearance and population increase, the Sand Rollers could be filling the role of a “native invader” in the...
Authors
Rulon J. Hemingway, Kenneth F. Tiffan, John M. Erhardt, Tobyn N. Rhodes, Brad K. Bickford
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU

The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2017 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners...
Authors
Kenneth Tiffan, John M. Plumb, Russell W. Perry, John Erhardt, Rulon J. Hemingway, Brad Bickford, Tobyn N. Rhodes, William P. Connor, Frank L. Mullins
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Smallmouth bass predation on subyearling fall Chinook salmon in Lower Granite Reservoir, 2016–2017 Smallmouth bass predation on subyearling fall Chinook salmon in Lower Granite Reservoir, 2016–2017

Predation by nonnative fishes is one factor that has been implicated in the decline of juvenile salmonids in the Pacific Northwest. Impoundment of much of the Snake and Columbia Rivers has altered food webs and created habitat favorable for species such as smallmouth bass Micropterus dolomieu. Smallmouth bass are common throughout the Columbia River basin and have become the most...
Authors
John M. Erhardt, Kenneth F. Tiffan, Rulon J. Hemingway, Brad K. Bickford, Tobyn N. Rhodes
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River Fall Chinook Salmon ESU, 1/1/2016 - 12/31/2016 Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River Fall Chinook Salmon ESU, 1/1/2016 - 12/31/2016

The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2016 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners...
Authors
William P. Connor, Frank L. Mullins, Kenneth F. Tiffan, John M. Plumb, Russell W. Perry, John M. Erhardt, Rulon J. Hemingway, Brad K. Bickford, Tobyn N. Rhodes
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Snake River Fall Chinook Salmon life history investigations Snake River Fall Chinook Salmon life history investigations

Predation by nonnative fishes is one factor that has been implicated in the decline of juvenile salmonids in the Pacific Northwest. Impoundment of much of the Snake and Columbia rivers has altered food webs and created habitat favorable for species such as Smallmouth Bass Micropterus dolomieu. Smallmouth Bass are common throughout the Columbia River basin and have become the most...
Authors
John M. Erhardt, Brad K. Bickford, Rulon J. Hemingway, Tobyn N. Rhodes, Kenneth F. Tiffan
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Ecology of the Opossum Shrimp (Neomysis mercedis) in a Lower Snake River Reservoir, Washington Ecology of the Opossum Shrimp (Neomysis mercedis) in a Lower Snake River Reservoir, Washington

The opossum shrimp Neomysis mercedis has expanded its range from the lower Columbia River upstream 695 kilometers into Lower Granite Reservoir where it is now very abundant. We studied Neomysis ecology in the reservoir during 2011–2015 to better understand the physical and biological factors that shape their distribution as well as their potential role in the food web. Benthic densities...
Authors
Kenneth F. Tiffan, John M. Erhardt, Brad K. Bickford
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU, 1/1/2014 - 12/31/2014 Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU, 1/1/2014 - 12/31/2014

The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2014 in association with U.S. Endangered Species Act recovery efforts and other Federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners...
Authors
William P. Connor, Frank L. Mullins, Kenneth F. Tiffan, Russell W. Perry, John M. Erhardt, Scott J. St John, Brad K. Bickford, Tobyn N. Rhodes
By
Ecosystems Mission Area, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Science and Products

boat on Salmon River boat on Salmon River
Salmon River Redd Surveys
boat on Salmon River

Salmon River Redd Surveys

Salmon River Redd Surveys

This mesmerizing video, recorded by Tobyn N. Rhodes, is from USGS Western Fisheries Research Center’s field work on the lower Salmon River this past Fall 2025. Partnering with the Nez Perce Tribe, Rhodes and his team were counting the number of fall Chinook salmon nests, known as redds, with a drone piloted from a jet boat.

By
Ecosystems Mission Area
boat on Salmon River

Salmon River Redd Surveys

Salmon River Redd Surveys

This mesmerizing video, recorded by Tobyn N. Rhodes, is from USGS Western Fisheries Research Center’s field work on the lower Salmon River this past Fall 2025. Partnering with the Nez Perce Tribe, Rhodes and his team were counting the number of fall Chinook salmon nests, known as redds, with a drone piloted from a jet boat.

By
Ecosystems Mission Area
Scientist measuring a Fall Chinook salmon
Scientist measuring a Fall Chinook salmon captured in the Snake River
Scientist measuring a Fall Chinook salmon captured in the Snake River
Scientist measuring a Fall Chinook salmon

Scientist measuring a Fall Chinook salmon captured in the Snake River

Scientist measuring a Fall Chinook salmon captured in the Snake River

USGS scientist Dalton Lebeda is measuring a Fall Chinook salmon captured in the Snake River. This study is being conducted to determine the percentages of natural and hatchery origin spawners in the upper reach of Hells Canyon.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Scientist measuring a Fall Chinook salmon

Scientist measuring a Fall Chinook salmon captured in the Snake River

Scientist measuring a Fall Chinook salmon captured in the Snake River

USGS scientist Dalton Lebeda is measuring a Fall Chinook salmon captured in the Snake River. This study is being conducted to determine the percentages of natural and hatchery origin spawners in the upper reach of Hells Canyon.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Picture taken with a sUAS (drone) of Hells Canyon
Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023
Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023
Picture taken with a sUAS (drone) of Hells Canyon

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023. In the bottom of the picture, you can see one of our USGS work boats pulled onto shore. USGS scientists are conducting redd surveys for spawning Fall Chinook salmon.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Picture taken with a sUAS (drone) of Hells Canyon

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023

Scenic picture taken with a sUAS (drone) of Hells Canyon, Fall 2023. In the bottom of the picture, you can see one of our USGS work boats pulled onto shore. USGS scientists are conducting redd surveys for spawning Fall Chinook salmon.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Filter Total Items: 14

Snake River Fall Chinook Salmon research and monitoring Snake River Fall Chinook Salmon research and monitoring

In Chapter 1, we report on development and application of an integrated population model (IPM) for the natural-origin fall Chinook salmon population upstream of Lower Granite Dam. This year’s efforts represent the third update to the model. Initial efforts focused on generating juvenile and adult abundance estimates, with estimates of uncertainty, for informing the life-cycle model and
Authors
Russell W. Perry, Dalton Hance, John Plumb, Kenneth F. Tiffan, Brad Bickford, Scott Louis Benson, Tobyn Rhodes, Steve Brink, Brad Alcorn
By
Ecosystems Mission Area, Western Fisheries Research Center

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River Fall Chinook salmon ESU Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River Fall Chinook salmon ESU

The portion of the Snake River fall Chinook salmon Oncorhynchus tshawytscha evolutionary significant unit (ESU) that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2020 in response to U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on changes in population abundance and habitat use by...
Authors
Kenneth Tiffan, Peter H. Barry, Dalton Hance, John Plumb, Brad Bickford, Tobyn Rhodes, Dalton Dirk Lebeda, Rulon J. Hemingway, Kenneth G. King, John Hargrove
By
Ecosystems Mission Area, Western Fisheries Research Center

Performance of subyearling fall Chinook salmon tagged with 8‐, 9‐, and 12‐mm passive integrated transponder tags in the Snake River Performance of subyearling fall Chinook salmon tagged with 8‐, 9‐, and 12‐mm passive integrated transponder tags in the Snake River

Inferences based on tagged individuals from a population are limited in part by the minimum size of fish that can be tagged. Smaller tags allow a greater proportion of a population to be represented by tagging and should reduce potential tag effects on fish performance. We evaluated different performance metrics of juvenile fall Chinook Salmon Oncorhynchus tshawytscha tagged with 8‐, 9‐...
Authors
Kenneth F. Tiffan, Tobyn Rhodes, Brad Bickford, Dalton Dirk Lebeda, William P. Connor, Frank L. Mullins
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Impact of smallmouth bass predation on subyearling fall Chinook salmon over a broad river continuum Impact of smallmouth bass predation on subyearling fall Chinook salmon over a broad river continuum

Smallmouth bass (Micropterus dolomieu) predation on subyearling fall Chinook salmon (Oncorhynchus tshawytscha) was examined in the Snake River (USA) to identify seasonal and habitat-related changes in bass diets, and associated subyearling consumption and loss in various riverine and impounded reaches. Smallmouth bass diets reflected opportunistic foraging that at times showed predation...
Authors
Kenneth F. Tiffan, John M Erhardt, Rulon J. Hemingway, Brad Bickford, Tobyn Rhodes
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook Salmon ESU Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook Salmon ESU

The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2018 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners...
Authors
Kenneth F. Tiffan, Russell W. Perry, John Plumb, Dalton Hance, Brad Bickford, Tobyn Rhodes
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Fall Chinook salmon (Oncorhynchus tshawytscha), sand roller (Percopsis transmontana), and smallmouth bass (Micropterus dolomieu) interactions in a Snake River reservoir: A tale of three species Fall Chinook salmon (Oncorhynchus tshawytscha), sand roller (Percopsis transmontana), and smallmouth bass (Micropterus dolomieu) interactions in a Snake River reservoir: A tale of three species

We studied some of the relationships between federally listed fall Chinook Salmon, Oncorhynchus tshawytscha, endemic Sand Roller, Percopsis transmontana, and non-native Smallmouth Bass, Micropterus dolomieu, in Lower Granite Reservoir on the Snake River. Because of its recent reappearance and population increase, the Sand Rollers could be filling the role of a “native invader” in the...
Authors
Rulon J. Hemingway, Kenneth F. Tiffan, John M. Erhardt, Tobyn N. Rhodes, Brad K. Bickford
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU

The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2017 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners...
Authors
Kenneth Tiffan, John M. Plumb, Russell W. Perry, John Erhardt, Rulon J. Hemingway, Brad Bickford, Tobyn N. Rhodes, William P. Connor, Frank L. Mullins
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Smallmouth bass predation on subyearling fall Chinook salmon in Lower Granite Reservoir, 2016–2017 Smallmouth bass predation on subyearling fall Chinook salmon in Lower Granite Reservoir, 2016–2017

Predation by nonnative fishes is one factor that has been implicated in the decline of juvenile salmonids in the Pacific Northwest. Impoundment of much of the Snake and Columbia Rivers has altered food webs and created habitat favorable for species such as smallmouth bass Micropterus dolomieu. Smallmouth bass are common throughout the Columbia River basin and have become the most...
Authors
John M. Erhardt, Kenneth F. Tiffan, Rulon J. Hemingway, Brad K. Bickford, Tobyn N. Rhodes
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River Fall Chinook Salmon ESU, 1/1/2016 - 12/31/2016 Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River Fall Chinook Salmon ESU, 1/1/2016 - 12/31/2016

The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2016 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners...
Authors
William P. Connor, Frank L. Mullins, Kenneth F. Tiffan, John M. Plumb, Russell W. Perry, John M. Erhardt, Rulon J. Hemingway, Brad K. Bickford, Tobyn N. Rhodes
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Snake River Fall Chinook Salmon life history investigations Snake River Fall Chinook Salmon life history investigations

Predation by nonnative fishes is one factor that has been implicated in the decline of juvenile salmonids in the Pacific Northwest. Impoundment of much of the Snake and Columbia rivers has altered food webs and created habitat favorable for species such as Smallmouth Bass Micropterus dolomieu. Smallmouth Bass are common throughout the Columbia River basin and have become the most...
Authors
John M. Erhardt, Brad K. Bickford, Rulon J. Hemingway, Tobyn N. Rhodes, Kenneth F. Tiffan
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Ecology of the Opossum Shrimp (Neomysis mercedis) in a Lower Snake River Reservoir, Washington Ecology of the Opossum Shrimp (Neomysis mercedis) in a Lower Snake River Reservoir, Washington

The opossum shrimp Neomysis mercedis has expanded its range from the lower Columbia River upstream 695 kilometers into Lower Granite Reservoir where it is now very abundant. We studied Neomysis ecology in the reservoir during 2011–2015 to better understand the physical and biological factors that shape their distribution as well as their potential role in the food web. Benthic densities...
Authors
Kenneth F. Tiffan, John M. Erhardt, Brad K. Bickford
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU, 1/1/2014 - 12/31/2014 Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU, 1/1/2014 - 12/31/2014

The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2014 in association with U.S. Endangered Species Act recovery efforts and other Federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners...
Authors
William P. Connor, Frank L. Mullins, Kenneth F. Tiffan, Russell W. Perry, John M. Erhardt, Scott J. St John, Brad K. Bickford, Tobyn N. Rhodes
By
Ecosystems Mission Area, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
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