This atlas traces the migratory paths of more than 100 bird species from both the Northern and Southern hemispheres. In addition to this a further 500 migratory species are catalogued, with details of their routes. The route, and how is is determined by the physical and behavioural characteristics of each individual species is described. Essential information on size, weight, wingspan, and journey distance for each of these migratory birds is also included, with every species fully illustrated. Threats and hazards to the world's bird populations are also taken into consideration.