Check out this amazing sound library from Yellowstone National Park!
There's everything here from American Coots to a Warbling Vireo, and from Anemone Geysers to Wolves.
You can immerse yourself in the aural landscape of America's first national park. The files available here were recorded in the park and are in the public domain. They may be downloaded and used without limitation; however, please credit the "National Park Service " where appropriate.