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Wildebeest migrating in the Serengeti. Migration, in ecology, is the large-scale movement of members of a species to a different environment.Migration is a natural behavior and component of the life cycle of many species of mobile organisms, not limited to animals, though animal migration is the best known type.
The excess individuals were expected to leave the patch, so that emigration rates were greater than immigration rates. In other words, sources were a net exporter of individuals. In contrast, in a sink patch, death rates were greater than birth rates, resulting in a population decline toward extinction unless enough individuals emigrated from ...
Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters (growth, recruitment, mortality and fishing mortality) are traditionally regarded as the significant factors determining the stock's population dynamics, while extrinsic factors (immigration and emigration) are traditionally ignored. Stocks fished ...
Population size can be influenced by the per capita population growth rate (rate at which the population size changes per individual in the population.) Births, deaths, emigration, and immigration rates all play a significant role in growth rate. The maximum per capita growth rate for a population is known as the intrinsic rate of increase.
Immigration and emigration are affected by the distance of an island from a source of colonists (distance effect). Usually this source is the mainland, but it can also be other islands. Islands that are more isolated are less likely to receive immigrants than islands that are less isolated.
Emigration is the act of leaving a resident country or place of residence [1] with the intent to settle elsewhere (to permanently leave a country). [2] Conversely, immigration describes the movement of people into one country from another (to permanently move to a country). [3] A migrant emigrates from their old country, and immigrates to their ...
The Theory of Island Biogeography has its roots in Wilson's work on the ants of Melanesia.MacArthur synthesized Wilson's ideas about competition, colonization and equilibrium into a simple graphical representation of immigration and extinction curves, from which one can determine the equilibrial species number on an island. [3]
Gene flow is the transfer of alleles from one population to another population through immigration of individuals. In population genetics, gene flow (also known as migration and allele flow) is the transfer of genetic material from one population to another. If the rate of gene flow is high enough, then two populations will have equivalent ...