Migrating birds

[andrewlee]

Birds migrate to sunnier climes with more plentiful food supplies, such as north Africa. So why do they bother to come back?

[mikewith]

There's an article on the subject here: http://www.theanswerbank.co.uk/Article.go?id=3434 but the main reasons appear to be food, familiarity and to avoid the evolution of predators!