Salmon & Steelhead Abundance

Reported abundance and productivity information extracted from the Elwha River monitoring record. Source notes accompany each figure.

Chinook

Natural-origin escapement, natural-origin spawners per spawner, and age-0 production are presented separately so the adult and juvenile monitoring records can be reviewed directly.

Source: SCoRE database. Annual natural-origin escapement, 2012–2025.

Source: SCoRE natural-origin escapement series. Brood-year spawners per spawner.

Sources: Age-0 production: 2025 Elwha Smolt Outmigration Report, Table 5; spawner abundance: SCoRE total escapement. Outmigration year is assigned to the preceding brood year.

Winter steelhead

The adult series distinguishes total escapement from natural-origin escapement. For years reported as natural-origin ranges, the plotted value is the midpoint of the reported range.

Sources: Elwha River annual steelhead SONAR escapement reports, 2014–2025. Natural-origin values for 2019–2024 are plotted as midpoints of the reported ranges.

Calculation: T−4 natural-origin productivity is return-year natural-origin abundance divided by natural-origin abundance four years earlier. The horizontal line at 1.0 represents replacement.

Summer steelhead

These values are observed adult summer steelhead from snorkel surveys, not whole-river escapement estimates. Survey extent differed in the early observations.

Source: Pess et al. (2024), Initial responses of Chinook salmon and steelhead to removal of two dams on the Elwha River, Washington State, U.S.A., Table 5 and Section 4.7. The 2013 and 2016 observations came from shorter surveys; standardized 2017–2020 surveys covered rkm 35–58.

Pink salmon

Only years with a reported adult return estimate are shown. No value is inserted for years without a defensible estimate.

Sources: 2021 and 2023 Elwha Chinook Escapement Estimate Based on SONAR reports; 2025 Elwha Smolt Outmigration Report (Denton et al. 2026 estimate). Values are approximately 2,300, 6,400, and 35,000.