Arent these specimens Kamchatka bighorn sheep (Ovis nivicola nivicola), because I was reading through Ultimate Ungulates and the photos of Snow sheep taken at the San Diego Zoo listed them as Kamchatka snow sheep (Ovis nivicola nivicola), and also is San Diego Zoo the only American zoo to ever have Ovis nivicola ???
I found out that at one time the Snow sheep (Ovis nivicola) was thought to be a subspecies of the American bighorn sheep (Ovis canadensis), I thought that I would share this interesting fact that I just found out