Simple on paper, maybe not so simple in practice; but just don't let him have the opportunity
He's a pup and has just learned about these super yummy things- OF COURSE he's going to try to get more! If your birds are ranging, maybe keep them penned till mid/late morning so they will lay in the nest box? That's worked well for me, at least until my mini Aussie discovered that she fits through the pop door
So you see, I feel your pain, lol! I personally wouldn't go to the e-collar unless and until more traditional training didn't do the trick, seeing that it's a young pup; it may not be necessary to go that route and anyway, unless you are very careful how you use the collar, it's possible to create more problems than you're solving with it. Maybe it would work to fill a blown eggshell with something gross for the pup to find? Mustard, a bit of hot sauce, vinegar...