I can't imagine it being a problem down in the canyons. I don't see anything in the regs but usually if you can't take your truck or ATV there, most hunters won't bother. Some will be on horses, but looking at the regs, that's pretty limited in the canyon too. I doubt many would go through all the trouble when there is much better hunting to be had in the higher elevations. I wouldn't worry about it.
Maybe check with the rangers to be sure though.