Tweet of the Day is a series of fascinating stories about our British birds inspired by their calls and songs.
Kate Humble presents the swallow. A flash of blue across farmland or a stableyard and a burst of twittering can only mean one thing, the swallows are back after their long migration from South Africa. No matter how grey the April weather, the sight and sound of a swallow dispels the winter blues at a stroke. These agile migrants arrive as the insect population is beginning to increase, and they are a delight to watch as they hawk for flies in the spring sunshine.