When animals know no boundaries

 

                                  Sam's pen. 

 

We all love travelling. Most of us are thrilled with the idea of exploring distant and unknown places. During the beginning of modern era, many famous navigators went out from their homes to explore the new lands. Among them Columbus, Vasco Da Gama, Captain Cook, and many others became legends. They travelled to discover about new lands; to acquire new knowledge. Do you know many animals are similarly fond of travelling long distances like us? But their travel is not related to enjoying aesthetic scenery of new habitats or to experience new habits. Their travelling is for their biological needs, to survive in this planet. Generally animals go for travelling to avoid unfavourable weathers, in search of food, for breeding, or to give protection to their next generation. Such type of travelling by animals is called animal migration.

Many animals migrate covering short distances, whereas some travel long distances, which can be 35,000km. This can be on the basis of altitude too. There are a variety of migration patterns. Some animals complete their one migration cycle in one year, while some complete it in just a day. Sometimes, it may take more than one generation. Migration in animals is a vast chapter in nature which describes many astonishing incidents, techniques and hidden reasons. Many of these are still unknown to us.. Many times the skills of these animals defeat the modern scientific technology. Surprisingly animals migrate very long distances and reach their destination successfully without compass, maps, atlases, GPS, or any other human-made devices.

Whenever we think about migration, the first thing that comes to our mind is migratory birds. Among the various migratory birds, the Arctic Tern shows the longest migration. They travel almost half of the world- from areas in Arctic region to the Antarctic zone. They travel approximately 35000 km in a total year, covering the to and fro journey. Apart from birds, migration is also common in some mammals. Gray whale and dolphins are front runners in this regard. It has been studied that whales cover a distance of 10000km-12000km during their annual migration. Migration of salmon fish and eel fish are no less striking. Their migration surpasses the thrill of all adventure stories. Eel fish start their migration from Europe and reach up to Sargasso Sea bounded by Atlantic Ocean. Their migration is only for fertilization. The newly hatched eels are no less efficient than their parents when it comes to migration. Just after hatching, they start their journey towards Europe, i.e. their native lands.

Among the reptiles, turtles are well known for their migration. Few turtle like loggerhead, travel from pacific ocean to Atlantic Ocean, almost half of the world. Reindeer of North America travels 1100km during their migration. It is not always true that migration involves travelling long distance. For example, amphibians like toad migrate short distances. During early spring, the toads go to the nearest water body for breeding and hatching of eggs. During summer they return back to their home on land. Migration is common in microorganism like copepod as well as in large animals like elephants and blue whales. It is common in insects like locusts, monarch butterflies and crustaceans like red crabs.

Our inquest about migration is not new. Since inception men were thrilled with the ideas of animal migration. This is evident from the approximately 7,000 years old cave paintings near Tassili fall in south-east Algeria which showed migration of animals in African grassland. Even the Greek myths depict the description of migratory animals. All these show the urge of mankind to know about the migration since centuries.