Friday's Findings - August 20th 2021

Release Date:

Assessing Migration and Survival of Pacific Salmon in Impounded Rivers of the Pacific Northwest, USA

Date: August 20, 2021 from 2-2:30 p.m. eastern time

Speaker: Toby Kock, Research Fish Biologist, USGS Western Fisheries Research Center


Click here to join the meeting

Or call in (audio only): 1 202-640-1187,

Phone Conference ID: 845 921 079#


Roza Dam, on the Yakima River, in Washington State.

Roza Dam, on the Yakima River, in Washington State.

(Credit: Toby Kock, USGS. Public domain.)

Summary: Large dams have been constructed on most river systems where Pacific salmon reside in the Pacific Northwest, United States. These dams have substantial effects on anadromous fish species by limiting access to important habitats, creating reservoirs in reaches that were formerly riverine, and causing injury or mortality to significant numbers of fish that pass through these projects. Research focused on evaluating movement and survival of juvenile and adult Pacific salmon is of critical importance in the region to provide resource managers with the information needed to implement modifications to dams and their operations to minimize negative effects. Researchers at the U.S. Geological Survey’s Western Fisheries Research Center specialize in conducting active telemetry studies to assess various aspects of migration behavior and survival in impounded river systems in the Pacific Northwest (and elsewhere). This presentation will provide an overview of the research techniques which have been developed and used and provide examples of key findings which have been used to improve conditions for Pacific salmon populations affected by dams.  

Related Content

Filter Total Items: 1
Date published: August 1, 2018
Status: Active

Scientific Support of Salmon and Steelhead Reintroductions in Impounded River Basins of the Pacific Northwest

Salmon and steelhead populations in the Pacific Northwest were severely affected by hydropower development that occurred during the first half of the 20th century.  Impassable dams were constructed on many rivers throughout the region which prevented returning adult salmonids from accessing important habitats where spawning and rearing historically occurred.  In the past two decades...

Contacts: Tobias J Kock