You may have heard many of these sound clips before, but this is the first one that we've heard that's a compilation of all the vocals verified by sound experts:
1- Mississippi Sounds.
2- Sierra Growls.
3- Puyallup, Washington Sounds 1973.
4- Snohomish County, Washington Sounds 1978.
5- Moaning Howl From Columbiana County, Ohio 1994.
6- Whoops & Knocks, Sierra Nevada Mountains, Eastern California
7- Florida Howls 2006.
8- Klamath, Oregon Sounds.
9- Estacada, Oregon Sounds 1972.
10- Snohomish County, Washington Whistles 1978.