Bear Bell and Natural warnings

One of the most surprising things for me when moving to the Pacific Northwest was the high number of people who are mauled by bears while out hiking and mountain biking. One suggestion I've heard and agree with is carrying a "Bear Bell". This is a tiny bell that you can strap to your backpack and that will jingle as you walk or bike through the trails. The noise should be enough to scare off most animals (including bears) and preventing you from accidentally sneaking up on them and scaring them into attacking. While the noise may seem annoying at first you'll quickly get used to it and considering the alternative (getting mauled) it's really not much of a nuisance. The down side is that the bell will scare off almost all wildlife so if your intent was to observe the animals you should instead use the suggestion below.

Another alternative is to listen for warnings from Nature herself. Typically when there are bears or other dangerous animals around you'll hear birds warning their fellow birds of the threat. If you listen closely while you're hiking you can pick up on these warnings (which are typically louder and more urgent sounding than a typical bird call) and alter your course. If you are unable to alter your course you could instead continue on the trail while shouting loudly for the next 100 or so meters to alert any animals to your presence and hopefully scare them away.