[Machine Translation] Why do they cross? Where do migratory birds come from and where do they go? How do you find out which birds are flying? How can I find migratory birds? Where do migratory birds come from and where do they go? Where do migratory birds come from and where do they go? ... This is the first book to answer all your questions about migratory birds, with a special focus on Japanese migratory birds. It is the first book to focus on migratory birds in Japan. The book is the first book to focus on migratory birds, especially in Japan.