The Wonders of Bird Migration: Navigating Nature’s Great Distances


Bird migration is a natural event in which birds fly over distances of hundreds and thousands of Kilometres in order to find better climate for habitats, feeding, breeding and raising their young. Usually birds migrate to escape harsh winter. Bird migration is mainly in Northern Hemisphere.

Migration of species such as storks, turtle doves and swallows was recorded as many as 3000 years ago by ancient Greek authors like Homer and Aristotle. Ornithologists have recorded arrivals of spring migrants in Finland in 1749. Modern techniques like birds ringing and satellite tracking are used to know migrants.

The Arctic tern is the Longest distance migratory birds travelling between arctic breeding grounds and the Antarctic each year. Albatrosses circle the earth, flying over the southern oceans. ManX migrate 14000 km between their northern breeding grounds and the southern Ocean. There are also shorter migrations like altitudinal migrations in the Andes and Himalayas.

Migratory birds navigate using celestial help from the sun and stars, the earth’s magnetic field and mental maps.

The main motivation behind migration is food. Some humming birds when given food do not migrate. The longer days of northern summer is propitious for breeding. When days shorten in autumn the birds fly to warmer regions. On the way the birds face troubles like physical exertion, predation, high stress, adverse climate etc.

Within a population not all birds migrate. This is called partial migration. Partial migration is very common in southern Hemisphere. In Australia. Forty four percent of non passerine birds and thirty two percent passerine birds are partially migratory.

Most migrations start in a broad front. Then the front narrows. Migratory routes are called flyways. These routes follow mountain ranges or coastlines, rivers, large stretches of open water. The routes taken on forward and return migration are different. A common pattern in North America is clockwise migration.Many birds migrate. For larger birds flying in flocks reduces the energy cost. Birds fly at varying attitudes during migration.On the peak Everest skeletons of pointail were found. Sea birds fly low over water, but gain altitude when crossing land. And reverse in case of land birds. However most birds migration is in the range of 15. To 600 meters.

Birds migration is not only confined to flying birds. Penguins migrate by swimming. Dusky grouse migrates by walking. Emus in Australia have been reported to go on long distance on foot during droughts.

In Orissa the Siberian birds come in winter to the lake chilika. Even in the reservoir of Hiraked dam, in winter foreign birds are seen. They come from far off lands.

Birds migration is one of the wonders of nature. Birds are technically perfect to know the routes of migration to and fro. This is the gift of God to them. We are astonished, how they are adept in knowing the foreign lands and topography. They come and go. it is simply wonder.

(The views expressed are the writer’s own.)

Radhakanta Seth is an Income tax officer in Sambalpur.  He is a Freelance writer and his articles have been published in some Oriya dailies like Sambad, Samaj, Dharitri and English dailies like The Telegraph and in a sociological journal ‘Folklore’ published from Kolkata.