In demography, replacement migration is a theory of migration needed for a region to achieve a particular objective (demographic, economic or social). Generally, studies using this concept have as an objective to avoid the decline of total population and the decline of the working-age population. Projections calculating migration replacement are primarily demographics and theoretical exercises and not forecasts or recommendations.
Contents
- Types of replacement migration
- Minimal replacement migration
- Constant replacement migration
- Results
- Examples of results
- Criticism
- References
The concept of replacement migration may vary according to the study and depending on the context in which it applies. It may be a number of annual immigrants, a net migration, an additional number of immigrants compared to a reference scenario, etc.
Types of replacement migration
Replacement migration may take several forms because several scenarios of projections population can achieve the same aim. However, two forms predominate: minimal replacement migration and constant replacement migration.
Minimal replacement migration
Replacement migration is a minimum migration without surplus to achieve a chosen objective. This form of replacement migration may results in large fluctuations between periods. Its calculation will obviously depend on the chosen objective. For example, Marois (2008) calculates the gross number of immigrants needed to prevent total population decline in Quebec. The formula is then the following:
Where:
Constant replacement migration
The constant replacement migration does not fluctuate and remains the same throughout the projection. For example, it will be calculated with a projection providing a migration of X throughout the temporal horizon.
Results
The raw results of replacement migration are not necessarily comparable depending on the type of replacement migration used by the author. Nevertheless, major demographics conclusions are recurrent:
Examples of results
Replacement migration to prevent the total population decline (annual average):
Replacement migration to prevent the decline of population of working age (annual average)
Criticism
Replacement migration as presented by the United Nations Population Division in 2000 is largely perceived as unrealistic as a singular way of fighting population ageing.
Increased migration could decrease the old age dependency ratio, which is expected to grow considerably in the next decades. However, the immigration need to effectively counter the greying of many industrialised economies is unrealistically high.
Replacement migration is also feared to negatively impact the environment.
Replacement migration is said to be more useful as an analytical or hypothetical tool.
Replacement migration has the following mid and long-term effects:
1) Instability due to lack of integration within the host culture leads to changes in state and cultural standards
2) Exponential replacement of original ethnicities on the targeted regions, due to two reasons:
- Increasing migration policy, to keep up the original population figures
- Replacement population´s increased birth rate above aborigin´s below-2 ratio. Natural birth rate of replacement population can be boosted by the welfare system of the host country
- Mass aborigin relocation and migration. A phenomenon similar to white flight.