Immigrants Flock to These U.S. Cities

The situation is much the same in Las Vegas, which ranks No. 4 on our list. It has been one of the fastest-growing cities in America in terms of gross domestic product (67% increase from 2001 to 2006) and foreign-born population (65% increase from 2001 to 2007). Census Bureau data show 58% of Sin City's working immigrants held vulnerable construction or service-sector jobs.

What happens to immigration during a downturn? Either it slows, or in some cases--depending on economic situations in their countries of origin--immigrants in the U.S. may return to their home countries. While the overall number of new arrivals to the U.S. has increased every year since 2003, experts say they're seeing a decline in the rate of growth for immigration, something that's likely to continue with a recession.

Oddly, that could be a good thing for the overall U.S. economy. With national unemployment already at 6.1%, a reduction in the potential labor force might provide some relief to communities hit particularly hard by the downturn.

"An outflow of immigrants, or a reduction in the inflow, could actually lessen the recessionary pressures," writes professor George Borjas, an expert on labor economics at Harvard University, in an e-mail.

But there also could be negative effects, depending on the severity of the downturn. For example, the presence of fewer immigrants might further relax the demand on housing. It might also disrupt the "mini economies" immigrants tend to sustain within their own communities.

"Immigrants have become so interwoven into the economic fabric of those cities, to loosen that fabric is going to weaken the city," says John Kasarda, a professor at the University of North Carolina's Kenan-Flagler Business School.

Of course, not all cities--or their immigrant populations--will be affected in the same ways. "The narrative is not always straightforward, as places are different," says Audrey Singer, an immigration expert at Brookings and co-editor of Twenty-First-Century Gateways, a book published earlier this year which identifies new trends in immigration.