Reasons for Bird Migration

Bird migration is a journey that many species of birds make each year. Migration is characterized by a large number of birds flying together from one specific location to another at the same time each year. The primary reason for migration appears to be food availability, but habitat and weather also affect migration patterns.

Many species of birds migrate along a flyaway or known migration pattern. This is the most common type of migration, and generally involves the birds flying to a temperate location in the summer to breed. These birds then return to a warmer location in the winter.

Birds in the Northern Hemisphere frequently fly to Arctic or sub-arctic regions in the spring and fly south for the winter. Birds in the southern hemisphere fly to the south during the summer and then fly back north in the winter. This type of bird migration is not as common in the southern hemisphere because the far southern hemisphere does not have as much land mass as the far northern hemisphere.

The primary reason that birds in the Northern Hemisphere fly south for the winter is that food becomes scarce in colder areas. Some species of birds, especially hummingbirds, will remain in a northern location during the winter if they have an abundant food supply. The primary advantage for flying north during the spring is the fact that artic areas have more daylight during the summer. This allows birds who are active during the day to produce larger clutches of eggs and spend more time feeding their young.

The advantages of migration must generally outweigh the disadvantages before a particular species of bird is likely to migrate. Disadvantages of migration include the high degree of stress and physical exertion that the birds must expand. Migrating birds are also more vulnerable to predation and some predatory birds time their migration to match the migration of their prey.