Researchers used Alaska Department of Fish and Game data and fish estimates from 2007 to 2016 to quantify the number and value of Pacific salmon originating from streams, rivers and lakes on the Tongass and Chugach national forests, the country’s largest and second largest national forests respectively.
The study focused on Chinook, coho, sockeye, pink and chum caught primarily in four commercial salmon management areas adjacent to the two forests.
According to study lead Adelaide Johnson, a Juneau-based hydrologist, the research group suspected that many of the ocean-caught Pacific salmon who support the fishing industry likely began their lives in forest streams that drain the Tongass and Chugach national forests.
Johnson and her colleagues used a three-step process to determine the number of fish originating from the Tongass and Chugach.
First, they calculated the total number of salmon caught in regional commercial harvest areas. Then, they subtracted the number of salmon originating from hatcheries – a process facilitated by the hatchery practice of marking juvenile fish – and the number of salmon that originated outside national forest boundaries, such as commercially caught fish born in Canadian rivers and rivers farther south in the contiguous United States.
Forest Service researcher Ryan Belmore, who like Johnson is based in Juneau, Alaska, said their findings underscore just how important Alaska’s forest rivers and lakes are for sustaining salmon. Belmore also noted that the study “vastly underestimates the value of salmon because it does not include subsistence and recreational salmon fisheries, which are critically important to local communities and the region’s economy.”
Researchers also said that salmon that do not originate from these national forests may still be supported by them for a portion of their lives. Pacific salmon fry that emerge upstream of national forest lands will migrate downstream and may use rivers, lakes and estuaries within national forest boundaries for rearing, they explained.
The Forest Service’s Pacific Northwest Research Station, headquartered in Portland, Ore., generates scientific knowledge to help the people make informed choices about natural resources and the environment.
More information can be found online at https://www.fs.usda.gov/pnw/.