The Nature Conservancy. Protecting nature. Preserving life.™

A primer on salmon habitat restoration projects in Alaska, the Prince of Wales Island. © Bridget Besaw

Throughout the historic distribution of wild salmon in the North Pacific, only Alaska and Russia’s Kamchatka Peninsula claim vast undeveloped watersheds that support healthy wild salmon populations. Alaska’s annual runs of wild salmon average more than 180 million. These fish sustain healthy wildlife, families and rural economies.

Yet Alaska is not immune to the development pressures that have strained salmon populations elsewhere in the North Pacific. With help from a range of private and public partners, the Conservancy is restoring salmon streams in the Tongass National Forest and in the Matanuska-Susitna Basin.

Living with Salmon in the Matanuska-Susitna Basin

Every year, the streams of the Matanuska-Susitna Basin fill with hundreds of thousands of wild salmon. Ocean-bright chinook, coho, sockeye, pink and chum pour into the rivers, feeding everything from world-class rainbow trout, char and grayling to bald eagles, brown bears and people.

Though the headwaters of the basin include some of the wildest lands in the entire country, the lower watersheds of the basin comprise one of the fastest growing areas in Alaska. This growth can harm salmon-bearing waters.

Little Susitna River watershed

The Conservancy and its partners are restoring once-lost habitat for wild salmon in Colter Creek, a tributary to the Little Susitna River. Colter Creek offers habitat for young coho and chinook salmon.

In 2008, the Conservancy:

• restored access to more than four miles of healthy salmon habitat by replacing four poorly-designed road crossings;
• replanted the streamside with native willow, grasses and wildflowers;
• used the restoration site as an outdoor living classroom for student groups.

Tongass Forest is a Salmon Forest

Lush and verdant Prince of Wales Island is the nation’s third-largest island and its forests are a giant nursery for wild salmon. Its coastal rainforest, salmon streams and estuaries provide for a rich a subsistence tradition among Native Tlingit and Haida people. More than 100 inches of yearly precipitation recharge the waters where five species of salmon spawn.

Salmon provide the foundation for the entire system, but fifty years of large-scale logging and roadbuilding has left its mark on Prince of Wales Island. A transition toward sustainability is now underway: Salmon habitat restoration projects are allowing wild salmon to return to spawn and grow in streams where the quality of habitat had declined.

Harris River and Gaandlaay Haanaa

In the Harris River watershed, the Conservancy has worked with the U.S. Forest Service to restore significant portions of these salmon-bearing waters. In this highly productive four-square mile watershed, crews have rebuilt a river and its tributaries. This has included:

• Carefully placing more than 350 whole trees and logs at 11 sites in the river channel to help create the natural logjams that allow the hydraulic force of the river to create deep pools. “Salmon need deep pools. They’re not going to over winter in a stream that freezes to the bottom,” says Rob Bosworth, who directs restoration projects for the Cosnervancy in the Tongass;
• Rebuilt 2,400 feet of the river, allowing the river to return to its native streambed;
• Decommissioned 1.2 miles of road and pulled out old culverts to improve fish passage on salmon waters.

Sal Creek

A series of landslides and other effects of erosion prompted the 2006-2007 restoration of Sal Creek, a coastal watershed on Prince of Wales Island. In this watershed, restoration crews:

• Restored fish passage by removing six deteriorated log culverts;
• Reconnected 27 streams blocked by 1.5 miles of abandoned logging road;
• Recreated a natural diversity of salmon habitats by strategically placing 385 whole trees in a four mile section of Sal Creek;
• Encouraged the regeneration of native conifer forest by thinning 100 acres of the red alder that grew in after timber was logged along Sal Creek.

Klawock Lagoon

A highway causeway built in 1964 blocked natural tidal flow through the north channel at Klawock Lagoon. This has impeded fish passage through the lagoon and caused a decline in beds of native eelgrass--a key nursery habitat for young fish.

• Passage restoration completed in 2011;
• Ecological monitoring continues for several years;
• A partnership with Klawock Watershed Council, Alaska Dept. of Transportation,  NOAA and others

Twelvemile Creek

• Placed more than 220 logs in a 1.5 mile stream section.
• Thinned 27 acres of streamside forest to promote the growth of bigger bank-stabilizing trees.
• Thinned 530 acres of dense upland second-growth forest.
• Closed five miles of temporary roads.