Hagerman National Wildlife Refuge, established in 1946 on Lake Texoma’s Big Mineral Arm along the Red River, protects 11,320 acres of wetlands, marshes, grasslands, woodlands, croplands, and open water in a transition zone between the Blackland Prairies and Eastern Cross Timbers. As Grayson County’s largest contiguous native habitat, it is a major wintering and stopover site on the Central Flyway, supporting large numbers of geese, ducks, pelicans, bald eagles, and more than 300 recorded bird species. Seasonal water management, cropland planting, and prescribed fire sustain habitat, while regulated oil and gas activity reflects the refuge’s long balance between conservation, industry, and public use.