I have hiked and backpacked all over the northern US, into Canada, parts of Alaska, and a couple of places in Europe. Talking with other hikers and backpackers, the constant danger used to be bears. You make noise as you hike down a trail to ensure that you never surprise a bear (some hikers wear a bell that makes noise as they hike, and the Yellowstone Rangers have a very cute joke about that), you hang your food, you cook away from where you sleep, all the same rules that we have followed for many years concerning bears. And it seems to be good advice, as bear attacks are rare, and almost always the result of someone doing something wrong.
But there is another large mammal that shares the bear ecology, and has expanded its range dramatically in the last 10 years. That is the mountain lion, also called cougar, puma, deer tiger, Mexican lion, mountain screamer, brown tiger, catamount, silver lion, mountain demon, Indian devil, purple feather, king cat, sneak cat, and panther. Studies of the mountain lion in California have shown that they are increasing their range, and have taken quite easily to using "wilderness land bridges" or areas left undeveloped between state parks, to move from one large park to another. These large cats (see photo to right to get a good idea of just how large these mammals can get, and no, that's not me in the picture) can roam many hundreds of square miles, and are increasingly getting into suburban areas where they come in contact with humans and their pets. The idea that mountain lions will never adapt to the suburban areas belie the fact that big cats have adapted well to every environment so far; from the deciduous and coniferous forests of cold Siberia that are home to the siberian tiger, to the grassy plains, savannas, open woodlands and dry scrub of the african lion. The family of cats, Felidae, has been very successful indeed, populating nearly every habitat on every continent except Antarctica and Australia (though the family felidae has been successsful populating Australia in recent times).
To make matters worse, all big cats have the same reaction to movement that your normal housecat has. They can't resist attacking. This makes the big cats very dangerous to humans who choose to do things like biking and running in mountain lion areas. In fact, a majority of recently recorded fatal and non-fatal attacks by mountain lions on humans have been as a result of these two activities. And unlike bear attacks, where the bear is either startled by the human and attacks defensively, or is attracted to the humans because of human carelessness with foodstuffs, mountain lions have been known to attack in what appears to be any opportunistic manner, sometimes after hours of careful stalking. This is quite different from bear attacks, and much less avoidable.
Because our land on 4 Mile Creek is perfect mountain lion habitat, I have tried to stay abreast of all the news coming out about big cat attacks. The last time we were there, my wife and I saw a lynx, which in itself is no small cat (I'd guess the one we saw at about 25 lbs) but it's not a cat that would readily attack a human. We try to hike every time we get the chance, and I want to make sure that we are safe. I don't think a tinkling bell will keep big cats away, and if my experience with smaller housecats and tinkling bells is any guide, I don't think I want a tinkling bell anywhere near me. Or yarn either.
So what is the general consensus on how to avoid an attack from a big cat? I haven't heard any real options put out there. Even so, when they do come out, the initial options are likely to be untested, and will change, just as the advice on bear attacks has changed over the years. With bears attacks, you are now advised to fight back as best you can, rather than play dead and have the bear eat you slowly, since bears love to eat already dead food. And you have to take into account who is giving the advice on big cat attacks, and what their motives are. If they are trying to keep cats as safe as possible, the advice is going to be different than if they are trying to keep humans as safe as possible (see previous example of bear attack advice). I'd think that the bear pepper spray we carry is a good last-second defensive measure, but I'm not even sure about that.
For now, I'll keep the guns handy, and hope I don't run across a mountain lion except at a very comfortable, respectable distance.
(photo of the mountain lion swiped from National Geographic)