Continuity mistake: When Bugs hides in the hole from Elmer, he puts the cow skull over the hole. Elmer then takes away the skull and then puts his head in the hole. At this point, you can see that the background is a desert, but when Elmer takes his head out of the hole, it has changed to a cliff. The background goes back to a desert when Bugs appears in the next shot.
Continuity mistake: When Elmer attempts to get gold by digging a hole in the ground and putting dynamite into it, he uses his pick to mark an "X" on the ground. When he puts dynamite in the hole and runs for cover, the "X" has disappeared.
Audio problem: When Bugs throws the stick of dynamite from the hole back at Elmer, Elmer screams but his mouth doesn't move.