New York's Jewish Population Is Growing Again After decades of decline, the Jewish population of New York City is growing again, increasing to nearly 1.1 million, fueled by the "explosive" growth of the ultra-Orthodox communities, a new study has found. It is a trend that is challenging long-held notions about the group's cultural identity and revealing widening gaps on politics, education, wealth and religious observance. Those findings, contained in the first authoritative study of the city's Jewish population in nearly a decade, challenges the entrenched image of Jews as liberal, affluent and well educated. Over the last decade wealthy, Ivy League graduates like those on the Upper West Side have increasingly lost population share relative to Orthodox groups, like the Hasidic population in Brooklyn, where college degrees are rare and poverty rates have reached 43 percent. Members of these Orthodox groups also have been known to be far more likely to adopt more conservative positions on matters such as abortion, same-sex marriage and the Israeli approach to the Palestinians. At the same time, among non-Orthodox Jews there has been a weakening in observance of quintessential Jewish practices. Participation in Passover seders has declined - 14 percent of households never attend one, almost twice as many as a decade ago. Reform and Conservative movements each lost about 40,000 members between 2002 and 2011 and nearly a third of respondents who identified themselves as Jews said they did not ally themselves with a denomination or claimed no religion. "There are more deeply engaged Jews and there are more unengaged Jews," said Jacob B. Ukeles, a social policy analyst and one of the principal authors of the study, which was conducted by the UJA-Federation of New York. These two wings are growing at the expense of the middle. That's the reality of our community. That shift appears quite likely to grow even more pronounced. Now, 40 percent of Jews in the city identify themselves as Orthodox, an increase from 33 percent in 2002; 74 percent of all Jewish children in the city are Orthodox. The New York area's Jewish population is the largest in the world outside of Israel and composes about one-third of the American Jewish population, which has been estimated at around six million (the census does not ask about religion). To conduct the study, a team led by Steven M. Cohen, a leading sociologist of the Jewish community, and Dr. Ukeles randomly called tens of thousands of homes in New York City and in three suburban counties, Westchester, Nassau and Suffolk. The surveyors asked if anyone in the household was Jewish; the researchers ultimately interviewed 5,993 adults for an average of 21 minutes each. The poll's margin of sampling error is plus or minus two percentage points. Although the researchers accepted as Jewish anyone who identified themselves that way, they also included people who identified themselves as "partially Jewish" - most of whom were adult children of intermarriages. They discounted respondents who, for example, said they were Jews for Jesus. UJA-Federation, a 90-year-old philanthropic organization, conducts the study roughly once a decade as a way of focusing its assistance in the eight counties it serves. The 2002 study found that the Jewish population of the city dipped below one million for the first time in a century, which was less than half the two million peak of the 1950s. Jews who moved out of the city seemed to stay in the region's suburbs. But the latest study, which will be released on Tuesday, showed that the city's Jewish population was reversing course and expanding. With the 316,000 on Long Island and 136,000 in Westchester, the eight counties together were home to 1.54 million Jews, a 10 percent increase since 2002. One factor contributing to the increase, the study found, is that Jews, like other Americans, are living longer. The number of Jews ages 75 and older rose to 198,000 from 153,000. The report found a number of competing trends. More than ever, Jews are sending their children to Hebrew day schools or yeshivas. Nearly half of adults ages 18 to 34 in the eight-county area had gone to such schools, compared with just 16 percent of those aged 55 to 69. On the other hand, most younger adult Jews who were not affiliated with any denomination had received no Jewish education whatsoever, a sharp decline from what prevailed a half-century ago, when most Jewish children attended Hebrew classes after school. The authors of the recent study said they were struck by the population's diversity. The rate of intermarriage remains at roughly 22 percent for all couples, but it is growing among the non-Orthodox. Between 2006 and 2011, the study found, one out of two marriages in which one partner was a non-Orthodox Jew was to a person who was not Jewish and did not convert to Judaism. About 12 percent of all Jewish households in the eight counties included one person who was nonwhite - either of mixed race, Hispanic or black, or Asian - usually as a result of adoption or intermarriage. Nearly one in four qualify as poor according to federal guidelines, an increase from one in five in 2002. The study put the number of Russian-speaking Jews - those who immigrated from the Soviet Union starting in the 1970s and their descendants - at 220,000. And it counted 493,000 Jews in Orthodox households, including so-called modern Orthodox, Hasidim and a third group commonly known as "black hat," or "yeshivish," who are as rigorous as the Hasidim but do not ally with a particular grand rabbi the way Hasidim do. The latter two groups are expected to grow but are "known to be self-segregated and relatively disconnected from the rest of the Jewish community,"the study said. The study acknowledged that the community's growing diversity "significantly complicates efforts to build an overall sense of Jewish community and Jewish peoplehood; particularly the largest groups - Orthodox and Russian-speaking Jewish households - function both as part of, and separate from the larger Jewish community." However, John S. Ruskay, UJA-Federation's executive vice president, said the different subcultures "share both history and destiny - and we will chart Jewish life and contribute to it - enriched by the diversity."