The Obed Wild and Scenic River, located on the Cumberland Plateau, has 13 species of crayfish living within or near its boarders. These 13 species come from two genera in the family Cambaridae, a solely North American crayfish family. There are seven families of crayfish worldwide.
The two Obed genera are highly specious (approximately 100 species each) and widespread. They are Cambarus and Orconectes. In total there are approximately 360 species of crayfish in the United States and Canada and approximately 80 species are known to occur in Tennessee.