The fertility value necessary to maintain the size of a population is generally taken to be 2.1. This means that the average female in that population must have 2.1 babies or more if the population is to sustain itself numerically. Most of the developed countries now have fertility values that are well short of this, spanning the range from 1.1 to 2.0. In Wikipedia are provided several estimates of national fertilities. Consider those from a 2014 tally by the World Bank. A few countries are hovering near breakeven such as Ireland, France, and New Zealand (2.0), and USA, UK, Sweden, Norway, and Australia (1.9). But these contrast with Hong Kong (1.1), South Korea and Singapore (1.2), Portugal, Poland, and Spain (1.3), and Italy, Japan, and Germany (1.4).
Some of these low fertility countries have been, and continue to be economic powerhouses. The conventional wisdom among economists warns that these countries are not on a sustainable path. Low fertility leads to a falling population with ever more older people and ever fewer working-age people to earn the income that will be necessary to finance the care of the elderly. Immigration is touted as the solution. Bring in workers from other countries—hopefully, with higher fertilities—to fill the perceived employment shortfall.
Immigration has been an effective way to fill labor shortages, but is it a long-term solution for a falling population, or merely a short-term fix? It has been claimed that it only takes a generation for newcomers to fall into step, fertility-wise, with the culture they settle into. If the newcomers acquire the social characteristics of the native population, then not much will have happened demographically; the population will have been increased, but the same downward trend will continue.
A recent article in The Economist sheds some light on this issue. It was titled Fecund foreigners?
“Xenophobes and xenophiles share a belief in the fecundity of newcomers. ‘Immigrants are more fertile,’ explained Jeb Bush, an erstwhile American presidential candidate (and xenophile) in 2013. ‘They love families and they have more intact families, and they bring a younger population.’ That is still just about true in America, but the gap is vanishing.”
“Between 2006 and 2013 the fertility rate among Mexicans in America fell by 35%, compared with a drop of 3% among non-Hispanic whites. In the Netherlands, the immigrant fertility rate is now almost exactly the same as the native one. Even in Britain, where a quarter of births are to immigrants, statisticians reckon that immigration has raised overall fertility by a mere 0.08 children per woman.”
What is referred to as “acculturation” seems to be a powerful force.
“But the big reason immigrants’ birth rates are falling is that they tend to adopt the ways of the host communities. This happens fast: some studies suggest that a girl who migrates before her teens behaves much like a native. Acculturation is so powerful that it can boost birth rates as well as cut them. In England, migrants from high-fertility countries like Nigeria and Somalia have fewer babies than compatriots who stay put. Those from low-fertility countries such as Lithuania and Poland have more.”
The article focuses of the industrial German town of Duisburg where a large number of immigrants, mainly Turks, came to work in the factories in the postwar years.
“In the early 1980s women with foreign passports in Duisburg had a birth rate much higher than native Germans….Most of the foreigners were Turks, who had settled in this Ruhr Valley city for its industrial jobs and brought their big-family culture with them.”
This chart is provided to illustrate the effect of acculturation on the birth rate.
The foreign-born reproduced at a healthy rate—at least for a while. However, within a generation or so their fertility fell to the same low level as that of the native Germans.
“Christine Bleks, who runs a children’s charity near Weseler Strasse, points to the front gardens of houses around Duisburg’s large mosque. They are small and orderly, with neat hedges and kitsch ornaments. The style is stereotypically German, she says. But the owners are mostly Turkish. As with gardens, so with families: immigrants have gone native.”
So if you happen to believe that falling populations are a problem, don’t count on immigration as a long-term solution.
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