Great blue herons are a wading bird indigenous (native) to the United States. These large birds have adapted to live in both fresh and salt water wetlands in both warm and cooler regions but are vulnerable to habitat loss. Since the 1950s, wetland habitats have been destroyed at alarming rates to provide space for human housing, shopping, and entertainment. These large predatory birds eat a wide variety of animals such as fish, crustaceans, small mammals, and amphibians.