Britain's Jewish population is on the increase for the first time since the Second World War, according to new research out today.
And the rise is down to a massive growth in bigger ultra-orthodox Jewish families, say researchers at the University of Manchester.
The Jewish population in the UK fell to a historic low of 275,000 in 2005, but that has now increased to 280,000 in 2008.
For the first time the fertility rate is greater than the mortality rate - and traditional Jewish families are having on average nearly seven children. The UK average birth rate is around 1.8.
Dr Yaakov Wise from the University's Centre for Jewish Studies, said almost three out of every four British Jewish births are ultra-orthodox, accounting for 46,500 out of a total UK Jewish population of around 280,000 or just under 17 per cent.
Secular Jewry numbers, on the other hand, are declining by about 2 per cent each year as a result of low birth rates, emigration to Israel and high rates of intermarriage - which is running at about 50 per cent.
The latest birth rates are calculated from annual records completed in December 2007 and are expected to rise even further in 2008.
Dr Wise said: "Though Britain's Jewish population is the fifth largest in the world, it has declined by 40 per cent from over 450,000 in 1950 to only 280,000 today.
"The high birth rate of ultra-orthodox Jews is now reversing this trend and that will have a major impact on the Jewish community in the years to come.
"The birth rate has exceeded the mortality rate for the first time since the war in each year since 2005.
"Secular Jewish women have on average 1.65 children whereas the ultra-orthodox have on average 6.9 - a huge difference."
"And that is a major contributory factor to my view that ultra-orthodox Jews are set to outnumber their more secular counterparts by the second half of this century.
He added: "The growing numbers of ultra-orthodox Jews in communities across the UK underline these trends.
"In Greater Manchester, for example, the ultra-orthodox number over 8,500 which is almost a third of the 28,000 Jews in the region. This is up from around one quarter only ten years ago.
"Approximately half of all the Jewish under fives in Greater Manchester are ultra-orthodox.
"And in Greater London the ultra-orthodox now account for 18 per cent of the Jewish population, up from less than 10 per cent in the early 1990s."
The UK figures were based on census data plus the regular monitoring of Jewish births by academics in Manchester and Leeds.
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