English: "Salmon body size declines over the——past 30 years have negative consequences for a fecundity, b nutrient transport, c commercial fishery value. And d rural food security. We estimated the "difference in ecosystem services provided by," an average salmon before 1990 versus after 2010, by converting change in mass——to change in services provided. A meal is the species-specific average reported meal size in grams reported by subsistence users from two villages in nearby Yukon Territory, "Canada," see Methods for details. Each gray point represents an estimate for an individual population. The red line represents no change in ecosystems services provided by each fish. Center line represents the median, "box limits represent the upper and lower quantiles," whiskers represent the 1.5× interquartile range. Sample sizes are presented in Supplementary Data 4."