In the lower 48 states, salmon have declined dramatically in abundance and distribution. Dam building on many of the most productive salmon rivers in our region, coupled with rampant resource extraction and thoughtless development and overharvest have all contributed to the decline of wild salmon in the lower 48. Dam building on the Snake, Sacramento and Upper Columbia rivers has completely blocked access to hundreds of miles of formerly productive habitat resulting in the extinction of hundreds of subpopulations of Coho, Chinook and Sockeye. Coho are now extinct in the Snake and Upper Columbia, although reintroduction efforts are underway. Coho salmon are listed as threatened or endangered in four evolutionarily significant units (ESU), while there are nine listed for Chinook. An ESU, or evolutionarily significant unit, is a population or group of populations that is reproductively isolated from other populations and that represents an important component of the evolutionary legacy of the species. Sockeye salmon are dangerously close to extinction in the Snake River system and are listed as threatened in Lake Ozette. Chum salmon are listed as threatened with extinction in the Columbia River and Hood Canal. Only Pink salmon have avoided listing thus far with relatively robust populations ranging from Puget Sound Washington up to Alaska. Fish farming has also contributed to the decline of wild salmon populations. Specifically, farming operations in the confined fjords of the Georgia Strait have led to infestations of parasitic sea lice and a concurrent crash in stocks of Chum and Pink salmon in the region. Recent scientific work suggests some stocks in the area may become locally extinct in just a few generations.
While salmon have suffered greatly in the lower 48 they are much stronger in northern British Columbia, Alaska and the Russian Far East. Low human population density, relatively pristine watersheds and healthy marine ecosystems support an abundance of salmon. Well managed commercial fisheries in Alaska supply much of the wild-caught salmon found in restaurants and markets today and with cautious science-based management these fisheries can be sustainable well into the future. All is not well in Alaska however, recently Northern Dynasty mining company has proposed building the world largest open pit mine in some of Bristol Bay's finest salmon habitat. Pebble mine would be positioned squarely between the Nushagak River, one of Alaska's most productive rivers for Chinook salmon, and Iliamna Lake, a vital sockeye rearing ground and one of the largest lakes on the West Coast. Native communities, commercial fishermen and sport fishermen are up in arms. The mine is an imminent threat to their livelihood and existence, the salmon.
Salmon are an iconic, keystone species in our watersheds and marine environments. Human impacts ranging from overharvest to deforestation have all taken their toll on our wild salmon. Fortunately they are exceedingly resilient, prone to successful recolonization and capable of hanging on even in the face catastrophe. Public awareness of the plight of wild salmon is increasing and the alarming possibility of losing these wild fish from our rivers and oceans is widely recognized. As a consequence, work is underway in many areas to protect and restore healthy habitats capable of sustaining robust runs of wild salmon.