There are lots of fun facts about bird migration. Did you known that:

• Bird migration is a seasonal journey that happens twice each year. Some bird species migrate but not all do. Birds that migrate are called migratory birds, birds that do not are called resident birds.
• Birds migrate in search of food. Food is abundant in warm, sunny places and nearly absent in dark, snowy locations. What's more, food is more plentiful in places with longer days than nights and long days give birds more time to hunt for food.
• Birds get their cue from nature. But it is the change in daylight hours rather than the change in weather that spurs birds to fatten up for the long flight ahead. Weather can be unpredictable, the number of daylight hours changes in the same way each year.
• Birds rely on a variety of senses to find their way. Birds identify locations by sight and smell. And they navigate by the sun and stars as well as the pull of the Earth's magnetic field.
• Birds return to the same locations each year. But when food runs short birds fly further migrating to a new location.
• Birds risk their lives each time they migrate. Predators and bad weather are the main risks birds face yet human development can also cause harm. When wetlands are drained and forests cut birds lose a place to refuel en route.