One of the neat benefits about nature photography is the opportunity to observe the creatures you're seeking to capture. We can spend so much time around our subjects that we learn a tremendous amount about their behavior through the long hours of observation. Over time, I've learned (and enjoyed) the courtship rituals of many birds and water fowl. I can usually tell when a fight is going to breakout - or when I fish has been spied by a heron.
In addition to just being plain down right fascinating, you can use this behavioral information to your advantage. I'd been watching a mating pair of Canada Geese as I saw another one looking for a place to land. I knew if he landed too close to the others that he was going to get run off. I prepared for the opportunity and was easily able to get a nice series of shots.
Waiting around for the perfect shot can either be boring or educational - your choice!
Stay in focus,
Mark