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Basin and Range

Home of some of the largest wetlands systems in the West, the Basin and Range's wetlands provide critical habitat for a wide variety of species of fish and wildlife, ranging from small populations of rare endemic fish to huge numbers of migrating waterbirds. The size and extent of the region's wetlands fluctuates widely from season to season and year to year, depending on precipitation. Isolated from each other for tens of thousands of years, individual basins have developed high levels of endemism among fish species; 17 species of sensitive, threatened and endangered fish are found in the region's shallow lakes and springs. Marshes around Malheur Lake (50,000 acres at high water levels - the largest natural freshwater marsh west of the Mississippi) and other terminal lakes support the largest inland colonial nesting colonies of waterbirds in the state. The wetlands of the Warner Valley and Summer, Goose, and Abert lakes attract tens of thousands of migrating shorebirds and waterfowl and provide breeding habitat for as many as 100 bird species. Harney basin wetlands draw peak numbers of up to 2.5 million ducks during the spring migration. Significant portions of the region's major wetland systems are managed for biodiversity values on state and federal wildlife refuges and special management areas at Summer Lake, Lake Abert, Warner Valley and Malheur and Harney lakes. Flood-irrigation of hay meadows on private lands in the Harney Basin provides important habitat for migrating and breeding birds, but many of the region's other historic wetlands have been converted to agriculture or degraded through water diversions and grazing.

For more information, see the Joint Venture’s Closed Basin plan