Climate change can have a profound effect on the distribution of animals and plants. There are good examples of natural variation in climate affecting species, such as the spread of several southern European birds (Cetti's Warbler, Savi's Warbler etc) to Britain. However, manmade climate change in the form of the greenhouse effect and global warming could have even greater effects. This book traces and explains changes in bird distribution in the northern hemisphere, with special reference to Britain and Europe, relating them to both climate change and other environmental factors.