What the wild salmon ecosystem is actually telling us:

The story of the world’s largest wild salmon fishery

Salmon, often known as the King of Fish, was once one of the most abundant creatures in the sea, dominating the waters in the northern hemisphere. Unfortunately it’s impossible to swim upstream forever, and in recent centuries, as industrialized human development spread across much of Europe and the United States, salmon populations decreased dramatically. The five species of salmon that reign in the Pacific Northwest are the Pink, Chum, Sockeye, Coho, and Chinook salmon. The lesser-known Masu salmon inhabits the Western Pacific, off the coast of East Asia. Together, these six species account for nearly all of the wild salmon eaten in the world.
Atlantic salmon haven’t been as fortunate as their Pacific kin. Due largely to human development in the form of dams, pollution, and overfishing, Atlantic salmon populations have plummeted in the past three centuries. The result is that a species once hundreds of millions strong is now listed as endangered. With a few small exceptions, all of the Atlantic salmon eaten today is raised in a fish farm; in fact, about 75% of the salmon eaten worldwide is farmed fish. The myth goes that when Christopher Columbus sailed to the Americas in 1492, he and his crew couldn’t sleep because of the perpetual whack of sea turtles bumping against the hull of their ship. Now, 500 years later, nearly every species of sea turtle is listed as endangered. In fact, so many plants and animals have become endangered or extinct in recent years, that researchers and environmentalists have started referring to it as the sixth mass extinction. New fishing technologies and poor fisheries management have turned the ocean into a shadow of what it once was. By some estimates, stocks of many large oceangoing fish have been reduced by 80% to 90%; sea turtles, many species of sharks, bluefin tuna, swordfish and toothfish (sold as Chilean Seabass) are just some of the groups threatened by overfishing. While there are still millions of fish in the sea, we are killing off too many of them way too fast. But for every rule there is an exception.  
Although now extinct in many of the rivers where they once bred, Pacific salmon still have something of a hold on their kingdom in the West.
In his book Four Fish: the Future of the Last Wild Food, Paul Greenberg writes that, “when it comes to salmon, Alaska is a little like a wise old man sitting on a far northern perch, overlooking the destruction that humanity has wrought farther south.” Alaska contains one of the world’s last and largest sustainable wild salmon fisheries, with hundreds of millions of fish returning year after year to swim up their natal streams to breed. Other examples of sustainable fisheries can be found inCanada, New Zealand and Iceland, however none compare to the size and scope of Alaska’s wild salmon fisheries. If Alaska is the country of salmon, Bristol Bay is its lifeblood; every summer in Bristol Bay 6,000 fishermen in 1,600 boats catch over 30 million salmon, roughly 10% of the world’s wild salmon harvest. When Obama traveled to Alaska earlier this month to highlight the social, economic and geopolitical impact of climate change, he visited Bristol Bay. Standing near the Bay waters, Obama spoke to a group of fishermen,saying “[Bristol Bay] represents not just a critical way of life that has to be preserved, but it also represents one of the most important natural resources that the United States has.” This past summer, I was one of the 6,000 fishermen sacrificing back, arms, hands, and fingers to harvest some of the most environmentally friendly salmon on earth. During six weeks of work, as I ripped salmon out of the gillnet, the smell of blood and diesel in the air, I began to understand what has kept the Bay sustainable in the face of "ever growing" environmental threat: an understanding by both the fishermen and the state of Alaska that environmental protection equates to the protection of the livelihood.