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Ryan Tomka

My research interests include juvenile salmon passage and survival at hydroelectric dams using acoustic and radio telemetry, operate radio telemetry equipment to monitor movements of adult salmon, develop and refine standard operating procedures for surgical implantation of transmitters, and train others in surgical implantation of transmitters. 

I am currently working in the Klamath River Basin studying survival of juvenile Chinook salmon migrating through reaches known to have Ceratomyxa Shasta.  I am also working on a study evaluating the performance of a Bio-Acoustic Fish Fence in the Sacramento River Basin.

I have historically studied urbanization effects on forage fish in Puget Sound (Coastal Habitats in Puget Sound).

Professional Experience

  • 2005 to Present – Biological Science Technician, U.S. Geological Survey, Western Fisheries Research Center, Columbia River Research Laboratory, Cook, WA

Education and Certifications

  • B.S. 2001. Zoology, Southern Illinois University, Carbondale, IL

Science and Products

A standard operating procedure for the preparation of purposely killed juvenile salmon used to test survival model assumptions

This document describes a standard operating procedure (SOP) for the preparation of purposely killed juvenile salmon, implanted with telemetry transmitters, to be released into rivers, lakes, or streams to test one of the survival model assumptions. Procedures for releases of purposely killed fish (hereinafter dead fish releases) were developed by staff from the U.S. Geological Survey’s Columbia R
Authors
Ryan G. Tomka, Theresa L. Liedtke, Conrad Frost, Collin D. Smith
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Behavior and movement of adult winter steelhead (Oncorhynchus mykiss) in the upper Cowlitz River Basin, Washington, 2017–18

Executive SummaryA 2-year radiotelemetry study was completed to monitor the movements of adult winter steelhead (Oncorhynchus mykiss) in the upper Cowlitz River Basin. A reintroduction program was established to restore healthy and harvestable populations of steelhead because volitional access to the area was blocked in the 1960s after construction of dams in the lower river. A trap-and-haul progr
Authors
Theresa L. Liedtke, Tobias J. Kock, Amy C. Hansen, Brian K. Ekstrom, Ryan G. Tomka
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Movements of juvenile Pacific Lamprey (Entosphenus tridentatus) in the Yakima and Columbia Rivers, Washington, 2018—A pilot study using acoustic telemetry

Telemetry has been an invaluable tool to improve our understanding of adult Pacific Lamprey (Entosphenus tridentatus) movements and to guide management approaches to protect and restore this species of concern. Juvenile and larval lamprey, however, are much smaller than adults, and have not been monitored with telemetry because available transmitters have traditionally been too large. With funding
Authors
Theresa L. Liedtke, Ralph T. Lampman, Z. Daniel Deng, Tyler E. Beals, Michael S. Porter, Amy C. Hansen, Tobias J. Kock, Ryan G. Tomka, Patrick Monk
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Evaluation of sockeye salmon after passage through an innovative upstream fish-passage system at Cle Elum Dam, Washington, 2017

Executive SummaryThe Bureau of Reclamation (Reclamation) and the Washington State Department of Ecology (Ecology), working with the Yakima River Basin Water Enhancement Project Workgroup (composed of representatives of the Yakama Nation; Federal, State, county, and city governments; environmental organizations; and irrigation districts), developed the Yakima Basin Integrated Plan (Integrated Plan)
Authors
Tobias J. Kock, Scott D. Evans, Amy C. Hansen, Russell W. Perry, Hal C. Hansel, Philip V. Haner, Ryan G. Tomka
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Preliminary evaluation of the behavior and movements of adult spring Chinook salmon in the Chehalis River, southwestern Washington, 2014

Recent interest in flood control and restoration strategies in the Chehalis River Basin has increased the need to understand the current status and ecology of spring Chinook salmon (Oncorhynchus tshawytscha). Spring Chinook salmon have the longest exposure of all adult Chinook salmon life histories to the low-flow and high water temperature conditions that typically occur during summer. About 100
Authors
Theresa L. Liedtke, William R. Hurst, Ryan G. Tomka, Tobias J. Kock, Mara S. Zimmerman
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Behavior and movements of adult spring Chinook salmon (Oncorhynchus tshawytscha) in the Chehalis River Basin, southwestern Washington, 2015

Recent interest in flood control and restoration strategies in the Chehalis River Basin has increased the need to understand the current status and ecology of spring Chinook salmon. Based on the extended period between freshwater entry and spawn timing, spring Chinook salmon have the longest exposure of all adult Chinook salmon life histories to the low-flow and high water temperature conditions t
Authors
Theresa L. Liedtke, Mara S. Zimmerman, Ryan G. Tomka, Curt Holt, Lyle Jennings
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Evaluation of juvenile salmonid behavior near a prototype weir box at Cowlitz Falls Dam, Washington, 2013

Collection of juvenile salmonids at Cowlitz Falls Dam is a critical part of the effort to restore salmon in the upper Cowlitz River because the majority of fish that are not collected at the dam pass downstream and enter a large reservoir where they become landlocked and lost to the anadromous fish population. However, the juvenile fish collection system at Cowlitz Falls Dam has failed to achieve
Authors
Tobias J. Kock, Theresa L. Liedtke, Brian K. Ekstrom, Ryan G. Tomka, Dennis W. Rondorf
By
Ecosystems Mission Area, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Behavior and passage of juvenile salmonids during the evaluation of a behavioral guidance structure at Cowlitz Falls Dam, Washington, 2011

Executive Summary A radiotelemetry evaluation was conducted during April–October 2011 to describe movement patterns, forebay behavior, and passage of juvenile steelhead, coho salmon, and Chinook salmon at Cowlitz Falls Dam, Washington. The primary focus of the study was to describe fish behavior near a behavioral guidance structure (BGS) and floating surface collector (FSC) deployed upstream of Co
Authors
Tobias J. Kock, Theresa L. Liedtke, Brian K. Ekstrom, Ryan G. Tomka, Dennis W. Rondorf
By
Ecosystems Mission Area, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Evaluation of angler effort and harvest of rainbow trout (Oncorhynchus mykiss), Lake Scanewa, Washington, 2010

A creel evaluation was conducted in Lake Scanewa, a reservoir on the Cowlitz River, to monitor catch rates of rainbow trout (Oncorhynchus mykiss) and determine if the trout fishery was having negative impacts on juvenile anadromous salmon (Oncorhynchus spp.) in the system. The trout fishery, which is supported by releases of 20,000 fish (2 fish per pound) per year from June to August, was develope
Authors
Theresa L. Liedtke, Tobias J. Kock, Brian K. Ekstrom, Ryan G. Tomka, Dennis W. Rondorf
By
Ecosystems Mission Area, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Tailrace egress and hydraulic conditions during tests of a top spillway weir (TSW) at John Day Dam, 2008

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Authors
T.L. Liedtke, C. D. Smith, R.G Tomka
By
Ecosystems Mission Area, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)

Data collected in 2010 to evaluate habitat availability for surf smelt and eelgrass in response to sea level rise on Bainbridge Island, Puget Sound, Washington, USA

This dataset includes biological variables showing surf smelt spawning presence, geological variables describing beach composition, and sample locations using RTK-GPS. This field data was also used to run the Sea Level Affecting Marshes Model (SLAMM; Warren Pinnacle Consulting, Inc., Warren, Vt)) to predict the changes to beaches over time, and under different sea level rise scenarios. Field sampl
By
Ecosystems Mission Area, Species Management Research Program, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Surgically tagging invasive sliver carp in Kentucky
USGS scientist Ryan Tomka shown surgically tagging invasive silver carp in Kentucky
USGS scientist Ryan Tomka shown surgically tagging invasive silver carp in Kentucky
Surgically tagging invasive sliver carp in Kentucky

USGS scientist Ryan Tomka shown surgically tagging invasive silver carp in Kentucky

USGS scientist Ryan Tomka shown surgically tagging invasive silver carp in Kentucky

USGS, Western Fisheries Research Center scientist tagging an invasive silver carp with an acoustic transmitter to evaluate the effectiveness of a BioAcoustic Fish Fence (BAFF) to deter upstream migration of invasive carp at Barkley Lock and Dam, Kentucky in October 2022.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Surgically tagging invasive sliver carp in Kentucky

USGS scientist Ryan Tomka shown surgically tagging invasive silver carp in Kentucky

USGS scientist Ryan Tomka shown surgically tagging invasive silver carp in Kentucky

USGS, Western Fisheries Research Center scientist tagging an invasive silver carp with an acoustic transmitter to evaluate the effectiveness of a BioAcoustic Fish Fence (BAFF) to deter upstream migration of invasive carp at Barkley Lock and Dam, Kentucky in October 2022.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Sockeye salmon
Sockeye salmon preparing to spawn
Sockeye salmon preparing to spawn
Sockeye salmon

Sockeye salmon preparing to spawn

Sockeye salmon preparing to spawn

Sockeye salmon preparing to spawn upstream of Cle Elum Dam, Washington.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Sockeye salmon

Sockeye salmon preparing to spawn

Sockeye salmon preparing to spawn

Sockeye salmon preparing to spawn upstream of Cle Elum Dam, Washington.

By
Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Congratulations to Ryan Tomka for Winning this Issue’s Photo Contest!

Congratulations to Ryan Tomka for Winning this Issue’s Photo Contest!

USGS Western Fisheries Research Center (WFRC) Fish Biologist, Ryan Tomka, is the winner of this issues photo contest. The image shows Ryan surgically...

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