There is a big problem with PZP in that it causes an eroding of the natural vigor of the wild horses and weakens there immune system leading to their decline. It also disrupts their social order. For this reason, I see it as a false solution. -- Yes, the Little Bookcliffs have excellent natural barriers and this area would lend itself so well to Reserve Design to assure genetically long-term viable, ecologically well adapted, and naturally self-stabilizing populations, or herds, of mustangs without coating their most intimate sexual organs with chemicals derived from ground-up pigs ovaries, which on the face of it should send up some mighty red flags, especially to biologists who understand physiology. You can read about my Reserve Design proposal at www.gofundme.com/mstngreservedesign. I have presented this to the BLM on several occasions. It is the right way forth for all concerned.