A fisherman's bobber takes the form of a hollow one piece plastic spheroid having two mating halves joined together by corresponding portions of a living hinge. The hinge extends outwardly from both halves. The interior peripheral surfaces of both halves are contoured to enable the halves to be joined together in locking engagement when the halves are pressed together and to permit the halves to be unlocked and swung apart when squeezed together. The portions of the hinge when the halves are locked together hold a fishing line in locking engagement therebetween.