Lower Klamath National Wildlife Refuge is a major protected wetland in the Klamath Basin on the California–Oregon border, managed by the United States Fish and Wildlife Service. Established by President Theodore Roosevelt in 1908 as the first waterfowl refuge in the United States, it grew from concern over heavy market hunting of migratory birds and became an important early step in American wildlife conservation. Designated a National Historic Landmark in 1965, it includes marshes, open water, uplands, and croplands managed for habitat, biodiversity, and public use. It supports diverse birdlife while facing continuing challenges from wetland loss, drought, water quality, and water-rights pressures.