MEXICO CITY — Lorenzo Martinez, an illegal immigrant who has lived in Los Angeles for six years, has a message for his kin in Mexico's Hidalgo state: Stay put.
The steady construction work that had allowed him to send home as much as $1,000 a month in recent years had disappeared. The 36-year-old father of four said desperation was growing among the day laborers with whom he was competing for odd jobs.
Sporadic employment isn't the half of it. Martinez said anxiety also was running high among undocumented workers about stepped-up workplace raids, deportations and increasing demands by U.S. employers for proof that they were in the country legally.
"Better not to come," Martinez said of anyone thinking about crossing into the U.S. illegally. "The situation is really bad."
That message seems to be getting through. There are numerous signs of a slowdown in illegal immigration.
* A recent survey by Mexican authorities shows that fewer Mexicans say they are planning to seek work outside the country. In the third quarter of 2007, about 47,000 said they'd be packing their bags. That's down nearly one-third from the same quarter a year earlier.
* U.S. border authorities arrested just under 877,000 illegal crossers in fiscal 2007, which ended in September, down 20% compared with the year before. A drop in apprehensions is often interpreted as a sign that fewer migrants are attempting the trip.
* The growth rate of the U.S. Mexican-born population has dropped by nearly half to 4.2% in 2007 from about 8% in 2005 and 2006, according to an analysis of census data by the Pew Hispanic Center.
* Employment of foreign-born Hispanics increased at a markedly slower pace in the first quarter of 2007 than during the same period in the previous three years, according to Pew. The slowdown was particularly noticeable in the bellwether construction industry.
Growth in employment of foreign-born Hispanics in that sector was 10.9% early this year, compared with an average first-quarter growth rate of 19.8% from 2004 to 2006.
* The growth in remittances sent to Mexico has dwindled to a trickle. Through October of this year, Mexicans living abroad sent $20.4 billion home to their families, a 1.3% increase over the same period in 2006, according to Mexico's central bank. Those sums were growing in excess of 20% annually just a few years ago.
What's behind the apparent decline? Some say it's primarily the slump in U.S. construction, which has been a magnet for undocumented workers over the last few years -- one in five Latino immigrants works in the building trades. Others say it's largely the result of stepped-up enforcement.
Proponents of tighter security note U.S. workplace dragnets and increased deportations have made big headlines in Latin America, deterring some would-be migrants. American authorities are installing hundreds of miles of new fencing along the southern border.
About 15,000 U.S. Border Patrol agents have been deployed to the region, 25% more than in 2006. Three thousand more are slated to be in place by the end of 2008.
"It's a combination of [more] personnel, technology and infrastructure," Ramon Rivera, a spokesman for the Customs and Border Protection agency, said of the falling arrest totals.
Immigration experts say tougher enforcement is but one of several explanations. The border buildup has encouraged more illegal immigrants to employ professional smugglers, whose success rate is higher than that of individuals, according to Wayne Cornelius, director of the Center for Comparative Immigration Studies at UC San Diego.
He said tougher enforcement had also discouraged many undocumented workers from returning to their homelands for occasional visits for fear of getting caught reentering the U.S. Fewer people coming and going across the border means fewer apprehensions.
The fall in arrests also fits a familiar pattern, one that traditionally has more to do with the strength of the U.S. job market than with walls or guards.
"It's the economy, stupid," Cornelius said.
Demographer Jeffrey Passel said the U.S. unemployment rate was the strongest correlating factor he had found in tracking migratory flows. Last month, the jobless rate for Latinos was 5.7%, up from 5% in November 2006.
"When it's easy to get a job, they come. When it's hard to get a job, they don't," said Passel, senior research associate at the Washington-based Pew Hispanic Center.
Border authorities apprehended a record 1.7 million would-be migrants in 2000, the height of the technology boom. That number tumbled over the next three years as the U.S. was rocked by recession, the Sept. 11 attacks and the loss of more than 2 million jobs. About 932,000 illegal crossers were apprehended in 2003, a 44% drop from 2000, according to Customs and Border Protection.