Alaska’s extensive coastlines exhibit a diversity of habitats from rocky cliffs to estuaries. Many stretches of beach are bounded closely by steep mountains, which limit settlement and many wildlife habitats to a narrow strip of coastline. These narrow bands at the boundary between land and sea support numerous fish and wildlife species, and they are critically important to the people living there. Food sources and shorelines are threatened by erosion, overharvesting, toxic shellfish poisoning, and predation by mammals, and are subject to isostatic rebound (uplift of land following glacial retreat), tectonic shift and sea-level rise. But information about shoreline resources adjacent to Alaska Native villages in southeast Alaska has been hard to find.
Pacific Northwest Research Station hydrologist Adelaide Johnson is looking at the physical features of these coastlines and assessing how they affect the subsistence lifestyle of local communities, as well as how they are likely to change in the next 100 years. She is studying sites at 13 primarily Alaska Native communities, examining how such physical features as slope, nearshore ocean depth, substrate type and fetch (length of open water) are related to biological features. Many biological resources, such as algae, butter clams and blue mussels, are important food sources for local residents, while eelgrass and giant kelp in the nearshore environment provide important juvenile salmon and mussel habitat. “I am interested in meshing the physical and social sciences to help people understand change, the range of their resources, which resources are the most threatened, and where refugias are,” said Johnson.
She reached out to Pacific Northwest Research Station social scientist and colleague Linda Kruger, who is gathering oral histories from Alaska Natives about the changes they are seeing in their environment. For example, some natives say that storms are more intense and beaches are starting to erode. Others say they have to go farther and farther out on the beach to find clams. With support from 20 high school student interns, the insights that Johnson and Kruger are developing will serve as a useful guide for southeast Alaska coastal communities. Funding is being provided largely by the Western Wildland Environmental Threat Assessment Center, and from partners at the National Oceanic and Atmospheric Administration, Alaska Department of Fish and Game, University of Alaska and multiple tribal groups. The guide will cover traditional and cultural resources used and will indicate where the greatest shoreline changes will occur, which shoreline areas will be the most resilient and which subsistence resources are most in need of protection.