Experts say that when we lose something, before we begin our search to find the lost thing we should picture the object in our minds. This kind of "visualization" causes the brain to do something wonderful. On the one hand, it appears to filter out many unnecessary sightings but, on the other, if something even remotely resembling the lost object comes into view, the mind seems to "jump" at it.
Good birders use the same trick. When they go looking for birds, their minds are just stuffed with visualizations of bird silhouettes stalking through tall grass, of sudden flutters between bushes, of daring hawk-dives from the sky.
When you begin feeling this amazing talent blossoming inside you -- it's a skill our ancient hunting and gathering ancestors must have known and consciously perfected -- you'll begin knowing a little about the mysterious manner in which nature study can enlarge us, sensitize us as humans... so that we live more vividly than before.