Sean is making sandcastles and singing ('Do you know the muffin man?') to himself. The boy in the lemon shirt is standing in the surf, turning to the left and to the right and calling his dog's name. The camera then cuts to a medium shot of the upper body of the boy in profile against an empty expanse of green/grey sea. As he calls 'Pippet! Come on, Pippet!' he turns to face the ocean and presents his back to the camera, the yellow of his shirt providing a subliminal signal for danger. To leave us in no doubt as to Pippet's fate, there is a cut to the stick bobbing on the water, and then a cut to below the surface, which the throbbing music on the soundtrack makes immediately clear is a POV shot of the shark.
Given the size of its bite radius, it's quite likely that the fish could have swallowed the labrador in one gulp and ingested it before it realised it was covered in fur. Then again, one of the principal components of a Great White's diet is seal, and seals have fur. Being a dog lover, Spielberg (whose own hound Elmer played the role of the Brody's spaniel) would never have thought of showing a canine death, but he was also canny enough to know that less is often more, and that the simple shot of a stick floating in the waves was enough to goose the audience up a little.
