some terriers are very vocal. i used to have a russell that bayed like a hound all through an earth. it was just his way. you new as soon as he was on. as his tone changed and he settled to a more frantic bay. i once broke through to him with a fox firmly fastened across his uper and lower jaw. he could'nt open his mouth but he was baying away like a good'n through clenched teeth . now a dog that bays at an empty hole and false marks is a different ballgame and no use to man or beast