NATIONAL HYDROGRAPHY DATASET-BASED MODELING OF STREAM HABITAT FRAGMENTATION AND STEELHEAD DISTRIBUTION IN CALIFORNIA ADROMOUS WATERSHEDS

摘要

California's salmon, steelhead, and other aquatic life depend on the health of our coastal rivers and streams. Healthy streams provide cool water, clean gravel, natural meandering channels, and access to upstream habitat. However, almost every stream along our 1,100-mile coastline has been fragmented by roads, dams, culverts, concrete channels, low-water crossings, or other structures that create difficult or impassable impediments for migrating fish.