Species: Oncorhynchus mykiss

Rainbow Trout or Steelhead
Species

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    The role of estuaries in the ecology of adult Pacific salmon and trout in Puget Sound

    The extensive loss or modification of estuaries throughout Puget Sound creates a significant challenge for adult salmon as they migrate to their natal streams to spawn. A 2024 report by University of Washington scientist Thomas Quinn looks at how different species of salmonids use estuaries to move from marine to freshwater environments. The report was commissioned by the University of Washington Puget Sound Institute with funding from the Environmental Protection Agency's National Estuary Program.

    Report cover with text and image of salmon swimming underwater.
    The role of estuaries in the ecology of juvenile Pacific salmon and trout in Puget Sound

    This overview describes the different ways that juvenile Pacific salmon and trout use estuaries, and why those differences are important for ecosystem recovery efforts. The report was commissioned by the University of Washington Puget Sound Institute with funding from the Environmental Protection Agency's National Estuary Program.

    Aerial view of Puget Sound showing multiple rivers and inlets. The text reads ‘The role of estuaries in the ecology of juvenile Pacific salmon and trout in Puget Sound’ by Thomas P. Quinn from the School of Aquatic and Fishery Sciences, University of Washington.
    Returning home: The Elwha's genetic legacy

    Following dam removal, migratory salmon have been free to swim into the upper Elwha River for the first time in 100 years. Their actual behaviors and reproductive success may well be driven by changes in their genetic makeup. Our seven-part series 'Returning home' examines how the fish are doing and whether the Elwha's genetic legacy remains intact. 

    View of the Elwha River above the site of the former Glines Canyon Dam in 2021. Photo: Sylvia Kantor
    Wild steelhead still a force in the Elwha

    Migration patterns have apparently reawakened for the Elwha River's wild steelhead. Studies show that the fish may have retained much of their genetic drive despite 100 years of being trapped behind dams. We continue our series 'Returning home: The Elwha's genetic legacy' with part two of seven. 

    A single steelhead trout swimming under water with rocks in background
    'Early migration gene' tied to unique population of Chinook

    Spring and fall Chinook salmon were thought to be alike until researchers discovered a gene for early migration. Now, federal biologists and legal experts are struggling to decide if spring Chinook should be granted their own legal protection under the Endangered Species Act.

    Caption: Chinook salmon (Oncorhynchus tshawytscha) swimming upstream. Photo: Ingrid Taylar (CC BY-NC 2.0) https://flic.kr/p/dmbyre
    New studies on emerging threats to salmon

    Chemicals, disease and other stressors can increase a salmon's chance of being eaten or reduce its ability to catch food. We wrap up our series on the Salish Sea Marine Survival Project with a look at some of the lesser-known, but still significant factors contributing to salmon declines in the Salish Sea.

    Chinook salmon leaping at the Ballard Locks in Seattle. Photo: Ingrid Taylar (CC BY 2.0) https://www.flickr.com/photos/taylar/29739921130
    Could anchovies and other fish take pressure off salmon and steelhead?

    A recent influx of anchovies into Puget Sound may have saved some steelhead from predators, but researchers seek more evidence to prove the connection. Our series on the Salish Sea Marine Survival Project continues with a look at these and other potential impacts from predators on the region's salmon and steelhead.

    A harbor seal hunting anchovies. From Howe Sound Ballet video by Bob Turner: https://youtu.be/Ycx1hvrPAqc
    Opening the black box: What’s killing Puget Sound’s salmon and steelhead?

    An intensive research program in the U.S. and Canada is studying why so few salmon in the Salish Sea are returning home to spawn. They are uncovering a complex web of problems involving predators, prey and other factors that put salmon at risk as they migrate to the ocean. We begin a four-part series on the Salish Sea Marine Survival Project, including new findings presented at the 2018 Salish Sea Ecosystem Conference last spring in Seattle. 

    Spring Chinook Salmon. Photo: Michael Humling, US Fish & Wildlife Service
    State of the salmon in watersheds 2016

    A biennial report produced by the Governor's Salmon Recovery Office provides stories and data about salmon, habitat, and salmon recovery in Washington, including Puget Sound.

    Salmon smolts. Photo courtesy of Governor's Salmon Recovery Office
    Advances in technology help researchers evaluate threatened Puget Sound steelhead

    New, smaller acoustic tags will allow scientists to track steelhead migrations in Puget Sound in ways that were once impossible. Will they provide answers to the mysterious decline of these now-threatened fish? 

    A steelhead (Oncorhynchus mykiss) in the Cascade River, WA, 2014. Photo: © Morgan Bond http://www.morganhbond.com/
    Mystery remains in deaths of young salmon

    The Salish Sea Marine Survival Project has mobilized dozens of organizations in the U.S. and Canada to find an answer to one of the region's greatest mysteries. What is killing so many young salmon before they can return home to spawn? A series of talks at the 2016 Salish Sea Ecosystem Conference brought together some of the latest research. 

    Key hypotheses include bottom-up and top-down processes and additional factors such as toxics, disease, and competition.  Graphic: Michael Schmidt, Salish Sea Marine Survival Project
    Will Ballard Locks withstand a major earthquake?

    For close to 100 years, Seattle's Ballard Locks has been one of the region's busiest waterways, drawing major boat traffic along with millions of tourists. But as it prepares to celebrate its centennial, the aged structure is also drawing the concern of engineers. They worry that an earthquake could cause the locks to fail, draining massive amounts of water from Lake Washington and Lake Union. In some scenarios, the two lakes could drop by as much as 20 feet, stranding boats, disabling bridges and causing big problems for salmon restoration.

    Ballard Locks from the air. Photo: Jeff Wilcox (CC BY-NC 2.0) https://www.flickr.com/photos/jeffwilcox/4805933588
    Salmon live in a topsy-turvy world upstream of the Ballard Locks

    Chinook, coho and sockeye salmon, along with steelhead trout, live in the Lake Washington watershed and navigate a treacherous route through the Ballard Locks on their way to Puget Sound.

    Returning sockeye salmon packed gill-to-gill in the viewing windows at the Ballard Locks fish ladder. Photo: Ingrid Taylar (CC BY-NC 2.0) https://www.flickr.com/photos/taylar/7511895940
    Are diseases playing a role in salmon decline?

    Chinook, coho and steelhead populations in Puget Sound have declined dramatically over the past 30 years. In some cases, counts of fish returning to the rivers are just a tenth what they were in the 1980s. While many possible causes of this decline are under consideration, some researchers are focusing on the combined effects of predators and disease. This article continues our coverage of the ecological impacts of disease in Puget Sound.

    Steelhead (Oncorhynchus mykiss). Photo: Eric Engbretson, U.S. Fish and Wildlife Service
    2014 state of salmon in watersheds executive summary

    This report documents how Washingtonians have responded to the challenges of protecting and restoring salmon and steelhead to healthy status. It also serves as a tool to summarize achievements, track salmon recovery progress through common indicators, and identify data gaps that need to be filled.

    2014 state of salmon in watersheds report cover
    2012 state of salmon in watersheds executive summary

    Salmon recovery demands both dedication among people with different interests, and sustained resources. This biennial report tells the story of the progress made to date and the challenges ahead.

    2012 State of Salmon in Watersheds Executive Summary report cover
    No salmon left behind: The importance of early growth and freshwater restoration

    The growth and survival of young salmon in streams, river deltas and floodplains are seen as crucial pieces of the salmon recovery puzzle. In part two of this two-part series, researchers at the Salish Sea Ecosystem Conference in Seattle say the complexities of the salmon life cycle require new coordination among scientists.

    Nisqually Reserve Fish Sampling March 2012. Photo: Michael Grilliot, DNR (CC BY-NC-ND 2.0) https://www.flickr.com/photos/wastatednr/6834386824
    What is killing young salmon in Puget Sound?

    Scientists say Puget Sound’s salmon are dying young and point to low growth rates in the marine environment as a possible cause. In part one of this two-part series, scientists consider threats facing young salmon in the open waters of Puget Sound.

    Chinook Salmon (juvenile) Photo Credit: Roger Tabor/USFWS. https://www.flickr.com/photos/usfwspacific/6093338474
    Lead Entities for salmon recovery in Puget Sound

    Lead Entities are local organizations in Puget Sound that develop salmon recovery strategies and priorities for the region on a watershed-based scale.

    Chinook salmon. Image courtesy of NOAA.
    Paper: A floating bridge disrupts seaward migration and increases mortality of Steelhead smolts in Hood Canal, Washington State

    A new study provides strong evidence of substantial migration interference and increased mortality risk associated with the Hood Canal Bridge for aquatic animals, and may partially explain low early marine survival rates observed in Hood Canal steelhead populations.

    Figure 1. Map of study area. Map depicts the four receiver arrays: Hood Canal Bridge (HCB), Mid Canal (MCL), Admiralty Inlet (ADM), and Strait of Juan de Fuca (JDF). Lower insets show single receiver locations for each year.
    Methods and Quality of VSP Monitoring Of ESA Listed Puget Sound Salmon and Steelhead: With Identified Critical Gaps 2012
    Download a November 2012 assessment of monitoring of viable salmonid population (VSP) criteria. 
    Chinook salmon (Oncorhynchus tshawytscha). Image courtesty U.S. Fish and Wildlife Service.
    Salmonids in Puget Sound

    Fish in the family Salmonidae (salmon, trout, and charr) play potentially integral roles in the upland freshwater, nearshore and pelagic marine ecosystems and food webs of Puget Sound.

    Chum salmon (Oncorhynchus keta). Image courtesy U.S. Fish and Wildlife Service.
    Kingdom
    Animalia
    Phylum
    Craniata
    Class

    Actinopterygii

    Order

    Salmoniformes

    Family

    Salmonidae

    Genus

    Oncorhynchus

    Classification
    Other Global Common Names
    truite arc-en-ciel
    Informal Taxonomy
    <p>Animals, Vertebrates - Fishes - Bony Fishes - Salmon and Trouts</p>
    Formal Taxonomy
    Animalia - Craniata - Actinopterygii - Salmoniformes - Salmonidae - Oncorhynchus - ), producing fertile offspring (Sublette et al. 1990).
    Short General Description
    A partially anadromous salmonid.
    Habitat Type Description
    Freshwater
    Migration
    <p>true - true - true - Anadromous forms migrate up to at least hundreds of miles between spawning streams and nonspawning marine waters. Stream-dwelling trout may spend an entire life in few hundred meters of stream (Moyle 1976). Lake-dwelling trout typically migrate to tributaries to spawn.</p>
    Non-migrant
    true
    Locally Migrant
    true
    Food Comments
    In lakes, feeds mostly on bottom-dwelling invertebrates (e.g., aquatic insects, amphipods, worms, fish eggs, sometimes small fish) and plankton. In streams, feeds primarily on drift organisms. May ingest aquatic vegetation (probably for attached invertebrates). Diet changes seasonally. In the ocean, the diet consists of fishes and crustaceans.
    Reproduction Comments
    Spawns usually in spring (February-June), or later depending on water temperature and location. Lays 200-9000 eggs (Wydoski and Whitney 1979), which hatch in 3-4 weeks at 10-15 C. Fry emerge from gravel 2-3 weeks after hatching. Many are sexually mature in 2-3 years. See Stearley (1992) for a discussion of the historical ecology and life history evolution of Pacific salmons and trouts (<i>Oncorhynchus</i>).
    Ecology Comments
    Normal life span 5-6 years (Simpson and Wallace 1982). Predation by Caspian terns and double-crested cormorants causes significant mortality of juvenile steelhead in the Columbia River estuary (Ryan et al. 2003). Aggressively defends feeding territories in streams. Has caused contraction of range of native brook trout in southern Appalachian Mountains region (Larson and Moore 1985).
    Length
    100
    NatureServe Global Status Rank
    G5
    Global Status Last Reviewed
    2008-01-15
    Global Status Last Changed
    1996-09-12
    Conservation Status Map
    <img src="http://www.natureserve.org/explorer/servlet/GetMapGif?CA.AB=S5&CA.BC=S5&CA.MB=SE&CA.NB=SE&CA.NF=SE&CA.NT=__&CA.NS=SE&CA.ON=SE&CA.PE=SE&CA.QC=SE&CA.SK=SE&CA.YT=S3&US.AL=SE&US.AK=S4&US.AZ=SE&US.AR=SE&US.CA=SNR&US.CO=SE&US.CT=SE&US.DE=SE&US.GA=SE&US.HI=SE&US.ID=S4&US.IL=SE&US.IN=SE&US.IA=SE&US.KS=SE&US.KY=SE&US.ME=SE&US.MD=SE&US.MA=SE&US.MI=SE&US.MN=SE&US.MS=SE&US.MO=SE&US.MT=S5&US.NN=SE&US.NE=SE&US.NV=S2&US.NH=SE&US.NJ=SE&US.NM=SE&US.NY=SE&US.NC=SE&US.ND=SE&US.OH=S5&US.OK=SE&US.OR=S5&US.PA=SE&US.RI=SE&US.SD=SE&US.TN=SE&US.TX=SE&US.UT=SE&US.VT=SE&US.VA=SE&US.WA=S5&US.WV=SE&US.WI=SE&US.WY=SE" alt="Conservation Status Map" style="width: 475px; height: auto;" />
    Global Range
    H - >2,500,000 square km (greater than 1,000,000 square miles) - H - Native to streams along the Pacific coast of North America from the Kuskokwim River, Alaska, south to northern Baja California; also the upper Mackenzie River drainage (Arctic basin), Alberta and British Columbia, and endorheic (i.e. having no outflow of water) basins of southern Oregon (Page and Burr 1991). The species has been widely introduced and established in suitable habitats all over the world (Lee et al. 1980). At sea, <i>O. mykiss</i> occurs throughout the North Pacific above 40° N from the North American coast to the Sea of Okhotsk (Burgner et al. 1992); it is most abundant in the Gulf of Alaska and eastern part of the North Pacific, conforming to the 5°C isotherm in the north and 15°C isotherm in the south. Seasonal shifts in distribution are correlated with changes in water temperature (Sutherland 1973).
    Global Range Code
    H
    Global Range Description
    >2,500,000 square km (greater than 1,000,000 square miles)
    ELEMENT_GLOBAL.2.105164