Coho salmon (Oncorhynchus kisutch), also referred to as silver salmon, spawn and rear in rivers, streams, and lakes that drain into the Pacific Ocean along the entire Oregon coastline. The river systems that support coast coho in Oregon flow from the rain-drenched coniferous forests of the Coast and Cascade mountain ranges, and the Klamath-Siskiyou ranges to the south. Most of the rivers transition to drowned river mouth and other estuary types before reaching the Pacific Ocean.
These two eco-regions (Coast-Cascade and Klamath-Siskiyou) support two genetically distinct runs of coast coho: Oregon Coast (OC) coho, which return to watersheds on the north and central coast, and the Southern Oregon Northern California Coast (SONCC) coho, which return to south coast (and northern California) watersheds. Like so many of the great salmon runs in the Pacific Northwest that used to return like clockwork to coastal rivers, lakes, and streams, Oregon’s coast coho populations experienced a steady decline throughout much of the 20th century. The combined effects of harvest, hatcheries, and habitat degradation resulted in a precipitous decline in the late 1990s that moved the National Oceanic and Atmospheric Administration (NOAA) Fisheries agency to list Oregon’s two coastal stocks as “threatened” under the federal Endangered Species Act (ESA): first, SONCC coho (listed in 1997), followed by OC coho (1998).
Since the mid 1990’s numerous coastal stakeholder groups have partnered with the federal government and State of Oregon to recover OC coho and strengthen populations in the SONCC.