Northwest Fisheries Science Center (NWFSC) Fish Ecology FE - Watershed


Elwha River dam removal
Elwha River Dam Removal Study
This project focuses on ecosystem response to dam removals on the Elwha River, Washington State. The Elwha Dam removal project is the largest project of its kind in the world and is the largest restorative action that has taken place in any Western U.S. Evolutionarily Significant Unit (ESU). Ecosystem response includes changes to physical habitat, aquatic food webs, thermal regime and all viable salmon parameters of listed and non-listed salmonid species. The project is based on the development and implementation of the Elwha Monitoring and Adaptive Management Guidelines (EMAM), which was developed as a collaborative effort between the Fish Ecology Division at the NWFSC, the Lower Elwha Klallam Tribe (LEKT), the United States Department of Fish and Wildlife Service (USFWS), the United States Geological Survey (USGS), the Washington Department of Fish and Wildlife (WDFW), and the National Park Service (NPS). We employ a variety of metrics to efficiently monitor ecosystem condition over space and time. This project provides data to assess changes for listed Elwha River salmon and trout populations (Chinook salmon (Oncorhynchus tshawytscha), steelhead (O. mykiss), and bull trout (Salvelinus confluentus)), and evaluate cost effectiveness of salmon habitat recovery plans and actions. Such analyses are crucial to help inform future large-scale dam removals for multiple ESUs across the Western U.S. Additionally, this project is contributing to the development of steelhead capacity models across the Olympic Peninsula and to understanding salmonid recolonization more generally (e.g., Cedar River salmonid recolonization).

Research Themes

Ecosystem approach to improve management of marine resources
The California Current Large Marine Ecosystem, Puget Sound and the Columbia River Basin are home to a wide range of freshwater and marine resources that provide a wealth of ecosystem goods and services. Ensuring the resiliency and productivity of the California Current and Pacific Northwest ecosystems requires an integrated understanding of their structure, function, and vulnerability to increased human population growth in coastal communities and competing uses of coastal waterways and oceans. The NWFSC‘s approach to understanding these large ecosystems integrates studies across ecosystems (terrestrial, freshwater, and marine) and scientific disciplines to inform resource managers responsible for conserving marine resources.
Habitats to support sustainable fisheries and recovered populations
Healthy oceans, coastal waters, and riverine habitats provide the foundation for aquatic resources used by a diversity of species and society. Protecting marine, estuarine and freshwater ecosystems that support these species relies on science to link habitat condition/processes and the biological effects of restoration actions. The NWFSC provides the habitat science behind many management actions taken by NOAA Fisheries and other natural resource agencies to protect and recover aquatic ecosystems and living marine resources. The NWFSC also maintains a longstanding focus on toxic chemical contaminants, as a foundation for regional and national research on pollution threats to fisheries and protected resources.

Research Foci

Characterize the interaction between marine, freshwater, and terrestrial ecosystem components
Although many species migrate between connected aquatic, marine, estuarine and freshwater environments they are commonly studied and managed as separate ecosystems. Environmental conditions in both marine and freshwater areas are strongly influenced by flows of water, sediment, organic matter and nutrients among ecosystems. Moreover, many threats (e.g., pollution, habitat loss, climate change, etc.) to marine organisms cross land-sea boundaries. Successful management of aquatic systems thus requires an understanding of linkages among ecosystems, including study of how specific habitats (e.g., headwaters, floodplains, submerged aquatic vegetation, nearshore zones, plumes and frontal regions) contribute to the productivity and capacity of ecosystems, and how to prioritize ecosystem protection or restoration within the context of the entire freshwater-estuarinemarine ecosystem.
Characterize the interaction of human use and habitat distribution, quantity and quality
The ability to define the state of an ecosystem requires insight into the natural processes within habitats, and how anthropogenic interactions with these processes can alter ecosystems and marine organisms. A wide diversity of human activities -- land use and water withdrawals, industrialization and dredging, fishing practices and climate change (e.g., ocean acidification) -- directly and indirectly impact critical freshwater, estuarine, and marine habitats. To best manage west coast marine, estuarine and freshwater habitats in a sustainable fashion, it is necessary to map the spatial and temporal footprint of human impacts and review their potential biological impact on each species of interest. Measurement parameters will be developed to determine the full range of human impacts using spatial data and improved habitat classification.
Develop effective and efficient habitat restoration and conservation techniques
Maintaining and re-establishing viability and sustainability of living marine resources requires conservation and rehabilitation or restoration of habitats upon which species depend. Common habitat restoration approaches and tech-niques often presume that habitats are static features of the environment, and that creation of stable habitats is a desirable restoration strategy. However, riverine, nearshore, and marine habitats are created and sustained by dynamic landscape, climatic, and oceanographic processes and biota are adapted to changing habitats that are within the range of natural variability. Hence, current restoration strategies often have limited success, in part because they fail to recognize larger scale processes that drive habitat change, and in part because they fail to recognize intrinsic habitat potential of individual restoration sites. The main goals of this research focus are to: improve understanding of how large-scale processes create diverse and dynamic habitats that support marine and anadromous species, better understand how human activities alter habitat-forming processes and habitats, develop new restoration techniques that are compatible with sustainable habitat-forming processes, and understand the variety of actions needed to adequately conserve intact critical habitats. In addition, NWFSC’s research will improve understanding of how new and existing habitat restoration and protection techniques affect fish and habitat at multiple scales (i.e., reach, watershed, Evolutionarily Significant Unit).


adaptive management
Adaptive management of strategies and actions intended to recovery salmon populations
bioenergetics modeling
model of organism's energy budget
dam removal
dam removal
related to removal of dams from rivers
environmental DNA extracted from water samples
effectiveness monitoring
evaluating whether actions had desired effects on physical, chemical, or biological processes
flat depositional feature of a river valley adjoining the channel
food web
complex of interrelated food chains in an ecological community
use of genetic markers to determine differential reproductive success between adults with different life histories
quantifying effects of spawning salmon on resident food web using stable isotopes of C and N
juvenile salmonid
early life stages of salmonids
salmon food webs
recolonization dynamics of salmon following reintroduction
habitat restoration
restoration genetics
genetic analysis to understand success or failure of restoration process
all salmonids
water temperature
temperature of water


Elwha Dam Removal Citizen Science Handbook
Citizen Science handbook is a work in progress, content for which will continue to be generated and updated by progressive student internships
Fish Diet and Invertebrate Drift Data in the Elwha River Watershed Before and During Dam Removal
NOAA technical report for data release of Elwha fish diet and prey availability
Methods for detecting fish and aquatic invertebrates using eDNA
Description of protocols & methods for identifying fish and macroinvertebrates from water samples
Molecular ecology collaboration with EFS
Collaboration with EFS scientists (Linda Rhodes) to apply molecular ecology methods to eDNA development


Class Actinopterygii
ray-finned fishes
Class Insecta
Family Salmonidae
Genus Oncorhynchus
Order Salmoniformes
Phylum Chordata
Species Lampetra tridentata
Pacific lamprey
Species Oncorhynchus clarkii
cutthroat trout
Species Oncorhynchus gorbuscha
humpback salmon, pink salmon
Species Oncorhynchus keta
chum salmon, dog salmon, Keta salmon
Species Oncorhynchus kisutch
Coho salmon, silver salmon
Species Oncorhynchus mykiss
rainbow trout, steelhead trout, syeelhead trout
Species Oncorhynchus nerka
kokanee, red salmon, sockeye salmon
Species Oncorhynchus tshawytscha
Chinook salmon, king salmon, spring salmon


Aimee Fullerton
Anna Kagley
Gabriel Brooks
George Pess
Principal Investigator
Karrie Hanson
Kinsey Frick
Krista Nichols
Internal Collaborator
Linda Rhodes
Internal Collaborator
Martin Liermann
Martin Liermann
Mary Moser
Internal Collaborator
Sarah Morley
Sarah Morley
Steve Corbett
Steve Corbett
Timothy Beechie
Todd Bennett
Todd Bennett