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Imagine: A wild salmon nursery, brimming with life, waiting for the great migration out to sea.

It begins here, where cottonwood smoke drifts across the yard at Mae Syvrud’s home each summer. It wafts from the smokehouse where her family’s prized wild salmon will cure for days at a time. This salmon comes from Alaska’s Bristol Bay — center of the salmon universe.

For Mae and her children and grandchildren, living with salmon is a long-held custom dating back thousands of years to when, as one Yup’ik fisherman once told me, “time was thin.”

Thousands of years. Millions of fish.

Why is Alaska’s Bristol Bay, even in 2010, home to tens of millions of wild salmon?

People here have an answer. This headwaters menagerie of big rivers, giant lakes, ponds and willowy streams is perfect habitat. To keep it healthy, this habitat needs protection.

Which is what brought me far into the remote Bristol Bay headwaters last summer. As Mae tended the fire in her family’s salmon smokehouse — yes, I’ve tasted her very own smoked salmon, and it’s heavenly — I went far upstream with fisheries biologists working to protect the places wild salmon need to survive.

Just what does a wild salmon need to survive? Scientists have a list of exactly what salmon do need, and briefly, they need big landscapes where water is clean and rivers flow free.

Bristol Bay is a wild Idaho-sized chunk of Alaska where common environmental challenges of our day — urban sprawl or air pollution or invasive species — seem distant. Roads are mostly absent. Bears and wolves and caribou roam here. Trout. Wolverine. Waterfowl. Moose. For a salmon, it’s perfect. Which is exactly why Alaska’s Bristol Bay is home to the largest runs of wild salmon anywhere on Earth.

To help protect the most remote and as-yet uncharted salmon habitat at a time when large-scale copper and gold mining is proposed for the region, The Nature Conservancy sent a crew of fisheries biologists to survey lakes and rivers for wild salmon.

On a day when I joined the crew, I waded shin-deep waters and carried a fine-meshed net on a long fiberglass pole. Our biologist, named Sarah, held a battery-powered electro-shocker that works like a big magic wand. When you poke this where the young three-or-four-inch-long fish are — beneath an undercut bank or down in a pool — they are momentarily stunned with a brief pulse of electricity.

If the guy with the net (me, in this case) is quick enough, fish are scooped from the water, then identified by species and photographed before they’re returned to the water. When scientists document the incredible habitat value of these waters in this way, it triggers existing regulatory levers in state and federal law.

Their lives begin in these streams, but salmon need up to four years and a trip to the Pacific Ocean before they’ll return. Along the way, they feed an entire ecosystem, beginning with the brown bears — see the iconic image on the Alaska state quarter. Some salmon fill the nets of a 125-year-old sustainable commercial fishery. Anglers come from around the world to test their luck with a fishing rod. Families like Mae’s catch some for the smokehouse.

But the migration journey of the salmon ends after they finally spawn in the very waters it began: the lakes and lacy network of tributaries that confluence into rivers such as the Nushagak and Kvichak.

So far, in two field seasons, we have discovered wild salmon in more than 90 miles of streams. This effort also has told us something more: Salmon are everywhere. We discovered salmon in 75 percent of the waters at the time of our surveys.

The image of a wild salmon nursery comforts people like Mae Syvrud, even as change whirs closer. Mae and a lot of her neighbors wrestle with the prospect of big-time development here. Most are simply opposed. In the meantime, Mae and her grandchildren tend the smokehouse, where she keeps the fire burning.

— Text by Dustin Solberg, Cool Green Science Blog

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A quest at the center of the salmon universe
Take a journey to Alaska's Bristol Bay, where a healthy ecosystem brims with wild salmon and rich tradition.