Originally posted by bessa-66 Yep, unless animals are used to people they'll be far away by the time you get your camera out.
there are times, not frequent of course, where wild life freezes and gives you an opportunity
also, if you are talking about birds or insects, you may find that they repeat patterns and if you are lucky and patient, you can see them, grab your equipment (quietly) and hope for a " repeat " performance.
often, and I am certainly no expert, I find sudden movement more of a trigger than noise or even sight:
if you have ever observe a predator, like a house cat, stalk prey, you will observe, slow quiet approaches and if the prey looks at the predator, the predator freezes
good lessons to be learned from such observations, IMHO, YMMV
no guarantees of course, that is why they are " wild " life photo opportunities