The sky above the town of Choteau, Montana ... of birds fills the air. (SOUNDBITE OF BIRDS SQUAWKING) JUHLIN: Lisa Hudnutt, a retired local teacher, quickly sets up a spotting scope. Colors ...

Each spring, hundreds of thousands of swans, geese, cranes and other waterfowl descend on a Montana lake on their way to the Arctic. A small town festival draws thousands of bird fans.