The first time that Lou ropes the Mustang, you can see that the horse is already wearing a rope halter when the rope reaches him.
The so-called "Mustang" of the title is plainly, and later so identified, as a purebred Palomino.
An opossum, seen in stock footage, is identified by narrator Buetel as a raccoon.
Buetel mentions having seen moose as a boy in Oklahoma, where they haven't been found since the Pleistocene Age.