A World on the Wing'A vaulting triumph of a book' Isabella Tree, author of Wilding 'A master storyteller, Weidensaul communicates so much joy in the sheer act of witnessing and such exhilaration in the advances of the science behind what he sees that we are slow to grasp the extent of the ecological crisis that he outlines.' Observer Bird migration remains perhaps the most singularly compelling natural phenomenon in the world. Nothing else combines its global sweep with