I recently sat at a table at the Power House, the coolest brew and bike shop in Hailey, Idaho, talking with three ambitious conservationists. Over dark stouts and savory burgers and fries, Merrill Beyeler, who runs a family ranch in Leadore, Tom Page, who ranches with his brother in the Pahsimeroi Valley, and Mark Davidson of Trout Unlimited described their efforts to not only restore their own lands, but to create a network of central Idaho ranchers who want to do the same.

We talked about the big picture (the dwindling funds available for protecting large Western landscapes), and about the ironies involved in restoration (the regulatory hurdles facing ranchers who want to reduce their public-land grazing). But mostly we focused on the threesome's efforts to help endangered chinook salmon, a small number of which still miraculously navigate the 900 miles from the Pacific Ocean to spawn in the Lemhi and Pahsimeroi rivers. By screening ditches, replacing clogged culverts and "re-watering" dry tributaries long disconnected from the rivers, they have opened up historic spawning habitat for the fish.

But, as senior editor Ray Ring points out in his cover story on Alaska's astoundingly prolific Bristol Bay ecosystem, just because you restore some habitat doesn't mean the fish will come. The system that sends salmon and steelhead to central Idaho – the Columbia River – has been so altered by dams, agriculture and other industries that wild salmon now return at a rate of less than 2 percent of their historic levels.

Bristol Bay's rivers, on the other hand, are far less developed, and millions of salmon still course through them every year, feeding everything from bears and gulls to flies and fungus. Year by year, scientists are uncovering the threads that make the Bristol Bay's ecological tapestry so rich and so resilient to short-term natural changes.

Can such threads be reassembled in the Columbia? Conservationists have tried valiantly for decades. They have forced dam managers to build fish ladders and allow more flow over the spillways; they have worked with farmers and ranchers to reduce pollution; and they have tried to re-introduce the biggest salmon predator, the grizzly bear, to Idaho's wild interior. Ultimately, they have made a compelling case that salmon will recover only if we remove dams, starting with the four on the Snake River.

The conservation-minded ranchers around the table nodded when I asked if they think the dams are a problem. They, like me, would like to see the red tide of salmon pulsing once again through the sagebrush and pine trees of central Idaho, filling those painstakingly restored tributaries. Bristol Bay, however, doesn't need restoration; it's already thriving. So let's leave this incredible ecosystem alone. Perhaps it can teach us how to preserve what we still have and to restore some of what we've lost.