Salmon are an icon of Cascadia. Their presence weaves threads of connectivity between marine, freshwater, and temperate rainforest systems and has nourished human and ecological communities for thousands of years. The five species of Pacific salmon (Oncorhynchus sp.)— sockeye, Coho, chum, Chinook, and pink— were once widespread from central California to the Bering Strait and are considered indicators of overall ecosystem health in Cascadia. Within these five species, hundreds of different subpopulations exist, each exhibiting a unique life history. From populations of pinks that migrate straight to the ocean as small fry and spawn near river mouths to genetic strains of Chinook that may spawn as far as 2,000 miles upstream and live to an age of seven, all Pacific salmon require intact watersheds home to clean water and thriving forests to persist. In turn, they encourage the health and productivity of Pacific temperate rainforests, as the rich marine-derived nutrients they carry in their bodies support a multitude of organisms, such as: aquatic invertebrates, freshwater fish, eagles, gulls, wolves, bears, and riparian vegetation. In southeastern Alaska in particular, up to 25% of the foliar nitrogen in riparian trees may originate from salmon dispersed on the forest floor by predators such as bears.
Salmon have been foundational to the cultures of coastal First Peoples for millennia, with an abundance of myth, ceremony, and art surrounding this essential food source still today. The persistence of Pacific salmon is not only crucial for the cultural heritage of Cascadia, but also for the economic wealth of the region. Currently, salmon support a $3 billion industry providing tens of thousands of jobs. Despite the importance of salmon in social, ecological and economic spheres, wild salmon have experienced degradation on a large scale since the arrival of European colonizers in North America.
Loss of habitat has resulted in significant population declines throughout southern Cascadia, with 30% of the historical populations currently extirpated and many remaining endangered or threatened in the contiguous US. This widespread destruction of habitat has come in many forms, including: river channelization, hydroelectric dams, pollution from agricultural runoff, and logging practices resulting in the destabilization of streambanks, reduced forest cover, and decreased watershed complexity. While healthy habitat still exists in Alaska, northern populations remain vulnerable to commercial fishing, imminent logging operations, and a changing climate. The introduction of hatchery-born and escaped farmed salmon into wild stocks poses an additional threat to the future of Pacific salmon. Both hatchery-born and domesticated fish are less adapted for survival in wild ecosystems and weaken the genetic resilience of salmon species.
Salmon represent a way of life deeply rooted in the forests and waters of Cascadia— connecting the culture, ecology, and economy of the region in a profound way. If they no longer return to the forested streams of their birth to spawn, the loss will surely have rippling effects. In order for Pacific salmon to persist in this era of human-caused mass extinction, remaining healthy habitat must be permanently protected and degraded habitat must be restored.
The permanent protection of old-growth forests within the Tongass will provide long-lasting crucial habitat for many unique populations of salmon. Furthermore, the restoration of coastal redwood ecosystems and the watersheds they hold will allow for previously extirpated or currently threatened populations to flourish once again.