Give an account of the role of migration in a population.

Explanation

Migration is the mass movement of a population from one place to another and back. The migration is a peculiar and unique kind of mass movement to avoid extreme conditions of weather. The Siberian creanes migrate from Siberia to Vedanthangal in Tamil Nadu, in order to avoid severe winter cold in Siberia. Likewise, some fishes migrate from sea to freshwater (anadromous migration Eg : salmon) and some freshwater to sea (catadromous migration Eg : Eel). Migration is of two types Emigration and Immigration.
Emigration : It is the type of migration to outside the habitat, due to over crowding of population. This helps to prevent over exploitation of habitat. It leads to establishment of new habitat.
Immigration : It refers to the movement of population into the habitat from outside. It results in beyond the carrying capacity mortality of immigrants or decrease the reproductive capability of individuals.