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I am a fish biologist with the WFRC Columbia River Research Laboratory. I joined the USGS in 2000, and my research has focused on Pacific salmon and dams in the Pacific Northwest. My expertise includes the use of imaging sonar systems to monitor abundances and behaviors of fish near collection and passage sites, as well as passage, migration, and survival of salmonids using acoustic telemetry.
Research Interests:
My research interests include the evaluation of dam passage and survival, development of fish passage options at high-head dams, reintroduction of salmon and steelhead to areas blocked by dams, and predation and behavioral studies near entrances to fish collection structures. I am currently working on studies that evaluate the effects of tidal cycles on juvenile salmon and native fish survival, assessments of migration and survival of juvenile salmon, and developing methods to automate imaging sonar data processing.
USGS scientists surgically implanting acoustic transmitters into juvenile Chinook salmon on the Shasta River, California. Study fish are tracked in the Shasta and Klamath Rivers as they migrate to the Pacific Ocean. Collected data are used to determine fish survival and migration behaviors.
USGS scientists surgically implanting acoustic transmitters into juvenile Chinook salmon on the Shasta River, California. Study fish are tracked in the Shasta and Klamath Rivers as they migrate to the Pacific Ocean. Collected data are used to determine fish survival and migration behaviors.
Taking a break in the fog on the San Joaquin River while trawling aboard the USGS Research Vessel Munson II.
Taking a break in the fog on the San Joaquin River while trawling aboard the USGS Research Vessel Munson II.
Capturing juvenile Chinook salmon in Cougar Reservoir, Oregon using a Lampara net.
Capturing juvenile Chinook salmon in Cougar Reservoir, Oregon using a Lampara net.
Juvenile Chinook salmon monitoring below the The Dalles Dam on the Columbia River.
Juvenile Chinook salmon monitoring below the The Dalles Dam on the Columbia River.
Trawling for Delta Smelt using a Kodiak Trawl in the Sacramento River aboard the USGS Research Vessel Sentinel.
Trawling for Delta Smelt using a Kodiak Trawl in the Sacramento River aboard the USGS Research Vessel Sentinel.
Honeycomb weathering of sandstone located on the shores of Puget Sound occurs when expanding salt crystals break fragments of rock, creating a small hole that becomes larger as the process repeats itself over time.
Honeycomb weathering of sandstone located on the shores of Puget Sound occurs when expanding salt crystals break fragments of rock, creating a small hole that becomes larger as the process repeats itself over time.
The ochre sea star is a common starfish found along the shores of Puget Sound. This intertidal dweller feeds primarily on mussels and snails, and may live as long as twenty years.
The ochre sea star is a common starfish found along the shores of Puget Sound. This intertidal dweller feeds primarily on mussels and snails, and may live as long as twenty years.
The Pacific sand lance is an important forage fish found in Puget Sound. They employ a unique strategy of burrowing into sand to rest and conserve energy, and to avoid predation. The USGS is currently studying forage fish spawning, and how human development may be affecting their habitat.
The Pacific sand lance is an important forage fish found in Puget Sound. They employ a unique strategy of burrowing into sand to rest and conserve energy, and to avoid predation. The USGS is currently studying forage fish spawning, and how human development may be affecting their habitat.
Tide pools provide habitat for a wide variety of Puget Sound flora and fauna. During low tides, the captive inhabitants of tide pools may be closely inspected.
Tide pools provide habitat for a wide variety of Puget Sound flora and fauna. During low tides, the captive inhabitants of tide pools may be closely inspected.
USGS scientists surgically implanting acoustic transmitters into juvenile Chinook salmon on the Shasta River, California. Study fish are tracked in the Shasta and Klamath Rivers as they migrate to the Pacific Ocean. Collected data are used to determine fish survival and migration behaviors.
USGS scientists surgically implanting acoustic transmitters into juvenile Chinook salmon on the Shasta River, California. Study fish are tracked in the Shasta and Klamath Rivers as they migrate to the Pacific Ocean. Collected data are used to determine fish survival and migration behaviors.
Taking a break in the fog on the San Joaquin River while trawling aboard the USGS Research Vessel Munson II.
Taking a break in the fog on the San Joaquin River while trawling aboard the USGS Research Vessel Munson II.
Capturing juvenile Chinook salmon in Cougar Reservoir, Oregon using a Lampara net.
Capturing juvenile Chinook salmon in Cougar Reservoir, Oregon using a Lampara net.
Juvenile Chinook salmon monitoring below the The Dalles Dam on the Columbia River.
Juvenile Chinook salmon monitoring below the The Dalles Dam on the Columbia River.
Trawling for Delta Smelt using a Kodiak Trawl in the Sacramento River aboard the USGS Research Vessel Sentinel.
Trawling for Delta Smelt using a Kodiak Trawl in the Sacramento River aboard the USGS Research Vessel Sentinel.
Honeycomb weathering of sandstone located on the shores of Puget Sound occurs when expanding salt crystals break fragments of rock, creating a small hole that becomes larger as the process repeats itself over time.
Honeycomb weathering of sandstone located on the shores of Puget Sound occurs when expanding salt crystals break fragments of rock, creating a small hole that becomes larger as the process repeats itself over time.
The ochre sea star is a common starfish found along the shores of Puget Sound. This intertidal dweller feeds primarily on mussels and snails, and may live as long as twenty years.
The ochre sea star is a common starfish found along the shores of Puget Sound. This intertidal dweller feeds primarily on mussels and snails, and may live as long as twenty years.
The Pacific sand lance is an important forage fish found in Puget Sound. They employ a unique strategy of burrowing into sand to rest and conserve energy, and to avoid predation. The USGS is currently studying forage fish spawning, and how human development may be affecting their habitat.
The Pacific sand lance is an important forage fish found in Puget Sound. They employ a unique strategy of burrowing into sand to rest and conserve energy, and to avoid predation. The USGS is currently studying forage fish spawning, and how human development may be affecting their habitat.
Tide pools provide habitat for a wide variety of Puget Sound flora and fauna. During low tides, the captive inhabitants of tide pools may be closely inspected.
Tide pools provide habitat for a wide variety of Puget Sound flora and fauna. During low tides, the captive inhabitants of tide pools may be closely inspected.