Fish Ecology

The Ecology Section examines how environmental variability, human activities and infrastructure influence food web interactions and species performance in freshwater and marine ecosystems. We have extensive experience in quantifying aquatic food web processes as they relate to growth, survival and production of key species of interest, especially resident and anadromous salmonids.

The focus of our research is the ecological analysis of Pacific Northwest fishes through age and growth structures such as: scales, fin rays and otoliths (small calcium carbonate deposits beneath the brain used in hearing and balance that grow in proportion to the overall growth of the fish). These structures are utilized as research tools for understanding life histories and habitat importance...

Low early marine survival rates of Puget Sound steelhead ( Oncorhynchus mykiss ), the state fish of Washington, have contributed to its dramatic population decline and current listing as a “Threatened Species” under the Endangered Species Act. Determining the cause(s) of this elevated mortality remains a primary objective of the Salish Sea Marine Survival Project, a large US / Canada effort...

Using an approach that involves a combination of field- and laboratory-based studies, we are investigating fish health factors that may be contributing to the failed recovery of Pacific herring populations in Prince William Sound, AK. Field studies are providing infection and disease prevalence data to inform the population models, serological data that indicate the prior exposure history and...

The ecological and economic costs of an invasive quagga or zebra mussel infestation in the Pacific Northwest of the U.S. would be significant. The development of invasive mussel monitoring programs in the Pacific Northwest provides a unique opportunity to evaluate a regional invasive species detection effort early in its development. Although efforts are underway to monitor for the presence of...

Juvenile anadromous salmonids all spend some portion of their lives in freshwater. This time may vary from days to years depending upon species and run. Spring Chinook Salmon and Coho salmon generally spend one year in freshwater and Steelhead may spend up to five years in freshwater prior to beginning their journey to sea. Several projects at WFRC – CRRL are investigating populations, life...

A study was conducted to identify habitat characteristics associated with age 0 White Sturgeon ( Acipenser transmontanus Richardson, 1863) recruitment in three reaches of the Columbia River Basin: Skamania reach (consistent recruitment), John Day reach (intermittent/inconsistent recruitment), and Kootenai reach (no recruitment).

Toxic chemical pollutants have been released into Puget Sound for decades by human activities. There’s a wide range of contaminants, from persistent compounds like polychlorinated biphenyls (PCBs) and flame retardants to contaminants of emerging concern. Aquatic species can be exposed to and accumulate contaminants, causing disease or disruption of biological processes like growth or reproduction...

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 resource...

Species Studied - Chinook Salmon ( Oncorhynchus tshawytscha )

Species Studied - Pacific Herring ( Clupea pallasii )

The WFRC has partnered separately with both the Skagit River System Tribal Cooperative and the Nisqually Tribe to research the use of otoliths (calcium carbonate deposits beneath the brain used in hearing and balance that grow in proportion to the overall growth of the fish) as a tool in examination of Puget Sound Fall Chinook salmon life history.