Found a baby birdie . . .

First off, not all birds eat worms, especially babies. You might want to research the wren and see what it eats. If it's very young, it might need to be fed some kind of mash with an eyedropper every hour or so. If you have a bird rescue organization somewhere nearby, give them a call--they could probably give you some good advice. My guess is the chattering is trying to call Mom....have you tried taking him back to the original spot, making sure predators can't get at him, hiding near by, and then just waiting for 1/2 hour or so to see if Mom does come back? You'd be surprised......they don't give up all that easily most of the time.