Flor Gutierrez has a bird's eye view of how immigrants – 37 percent of California's labor force – are reacting so far to a punishing recession.

She runs El Mercadito Latino in Elk Grove, where Mexicans and Central Americans shop and wire money to family back in their home countries. In December, she said, customers wired the same amount of money as they always have during a holiday month. But Gutierrez is bracing for a plunge.

"They definitely are buying less for themselves," she said. "We may see people getting by with less here, so they can continue to help out those back home who are even worse off."

Gutierrez's observations mirror what researchers at the Migration Policy Institute, a nonpartisan Washington, D.C., think tank, describe in a report issued Wednesday.

"Immigrants and the Current Economic Crisis" reviews statistical research and other information and concludes that there is no hard evidence of illegal or legal immigrants leaving in droves because jobs have dried up.

In addition to agriculture, immigrants are concentrated in construction, manufacturing and services, industries that have been battered by the downturn.

No doubt, tough times have already prompted some to leave U.S. soil and produced a "flattening" in the estimated number of illegal immigrants entering to seek jobs since 2007, said Demetrios Papademetriou, president of the Migration Policy Institute, which studies U.S. and global migration trends and policies.

But home countries, especially those tightly linked to the U.S. economy, such as Mexico and those in Central America, are not hospitable places to search for work, either.

Drug trafficking violence and crime in Mexico are disincentives to returning, as is immigrants' strong sense of responsibility to provide for family, the report says.

"What we don't know," Papademetriou said, "is if the economy is going to become so bad here that to barely subsist in a much friendlier atmosphere – back with one's family – will tip the scales."

The report examines immigration patterns as far back as the early 1800s. Trying to predict the recession's impact on foreign workers, it says, "is daunting because there has been no comparable crisis in recent memory."

The report does offer the incoming Obama administration food for thought.

Researchers contend that U.S. policies encourage undocumented workers to remain in the United States and cling to whatever work they can find and wait out a downturn. In contrast, they say, the European Union's policy of free transit for EU citizens affords migrant workers "the ease of circulation."

Poles and other Eastern Europeans, for example, were able to legally fill labor needs in Ireland and Great Britain in the last decade. Ireland's foreign-born population rocketed from 1 percent in 1997 to 14 percent in 2007, Papademetriou said.

But when the Western economies slowed in 2007 – and the Eastern economies improved – laborers left Ireland and Britain in large numbers.

The key to the migrants' decision to leave, Papademetriou said, is that they knew they could return legally if job opportunities became available.

Spain, Papademetriou said, is in a fix comparable to the United States. Africans and South Americans were drawn to work there, legally and illegally, when the economy was healthy.

Now, the immigrants don't want to leave because they don't have a guarantee they could ever return.

One Sacramento Valley construction worker, 27, is debating whether to return to Mexico next week.

He has worked as a building and home insulation installer for seven years.

He hesitates to leave primarily, he said, because he knows how hard it will be to return. He requested anonymity because he fears being identified.

"My company let me go last week," he said. " They said that once things get better, they'll call me back."

Call The Bee's Susan Ferriss, (916) 321-1267.