An online friend of mine who lives in California plans to do some hiking in the near future, most likely up Mt. Wilson. Mountain lions can be a problem on the trail he'll be taking, and he'll be hiking alone. This means a cat can come up on him suddenly, with little or no warning. He is looking for the best defense possible against the cats. He was thinking of something like this, or perhaps this. Would these even stop a mountain lion, or at least frighten it away? Obviously he wants a non-lethal defense. Any ideas? Maybe something out there which keeps mountain lions away with scent?