2007-03-12 04:00:00 PDT Agua Prieta, Mexico -- As night fell and migrants at the shelter behind the Holy Family Catholic Church prepared to bed down, Roberto Valenzuela threw his powerful baritone into the old folk song "Cielito Lindo."
The other men -- most of whom had landed at the shelter after being caught by the U.S. Border Patrol as they tried to cross into the United States -- paused to listen: "Canta y no llores!" Valenzuela sang. "Sing and don't cry!"
Valenzuela, 47, had made his living for years as a mariachi in Phoenix and Los Angeles. He would head north illegally for a few months and be set for the rest of the year. But by late fall, the Border Patrol had caught him twice and he planned to try crossing once more before heading home to Huachinera, two hours south.
Stepped-up enforcement by the Border Patrol and National Guard appears to be deterring some would-be crossers. From October to February, the Border Patrol made 30 percent fewer arrests of people trying to slip across the border this year than it did in the same period last year.
But many migrants at Holy Family shelter -- one of four in this city of 70,000 set among copper mines and cattle ranches right at the border -- said they couldn't give up. They had sold all they owned and ridden buses, hitchhiked or hopped freight trains from southern Mexico and beyond, intent on reaching the United States.
A slight man from Chiapas, too nervous to give a name, who said he sold his small plot of land to go north, said he would not return to his wife and five children empty-handed.
And Luis Enrique Guido Ruiz, a carpenter from Masaya, Nicaragua, bundled in an oversize red parka, said he was continuing north despite being mugged and hospitalized for 15 days on his way -- as evidenced by an angry scar on his cheek.
"We're migrating because the poverty in our countries gets worse every day," Guido, 39, said after a dinner of soup and tortillas.
The Rev. Cayetano Cabrera, the priest who runs the shelter, said the migrants turning up at his door lately have undergone more punishing experiences than in years past.
"Before, they used to try crossing again (right away), but these days they have suffered more," he said. "They've walked further. They're sick.
"But I don't think people will stop crossing," he said.
Law enforcement officials point to the 30 percent drop in arrests as proof that their efforts in sealing off the border are working. All nine of the southwestern border's enforcement sectors saw decreases; the largest -- 66 percent -- was in the Yuma sector, and the smallest -- 11 percent -- was in the San Diego sector, where enforcement was already strong.
The Border Patrol added 1,000 new agents last year, and its force of more than 12,000 now is backed up by several thousand National Guard troops. New measures also include miles of concrete-filled steel vehicle barriers; surveillance cameras, motion detectors and flood lights; and mobile lookout posts equipped with infrared surveillance equipment. In New Mexico and West Texas, the Border Patrol has experimented with sending Mexican migrants before a judge, who sentences them to jail time rather than releasing them back across the border.
"We're starting to see tangible results from these efforts in the form of reduced apprehensions," said Todd Fraser, a spokesman for the Border Patrol.
But arrests have fallen dramatically and risen and fallen again several times over the past 15 years at the same time the number of Border Patrol agents has risen steadily. Since 1992, the force has tripled and its budget has risen fivefold to nearly $2 billion this fiscal year, which ends Sept. 30.
At the Mexican consulate in Tucson, Deputy Consul Enrique Muñoz charts the locations of people who die trying to cross the border. His wall map shows that the number of fatalities in his jurisdiction jumped more than 20-fold in the 16 years he's been on the job. Nationally, the death toll swelled to 473 in 2005, dropping slightly to 453 last year. Deaths have risen as migrants have sought increasingly remote routes to avoid the Border Patrol and have found themselves farther and farther from sources of water and assistance.
The hardening of the border also has encouraged more Mexican migrants to settle permanently in the United States, rather than return after each season of work. And many immigration analysts say that's leading more family members to follow workers north.
Consider María de la Cruz and her three sons. The young men left their mining town in Zacatecas six years ago and found work in Chicago. With no family remaining at home, de la Cruz, 51, decided to join them, and her sons hired a smuggler, who guided her and about 30 other migrants in the dark across a mountain near Naco, Ariz.
"About 4 in the morning, the helicopters came and the coyote told us to run," she said. "We didn't know the terrain, and I broke my foot. The Border Patrol caught us all."
With a monthslong convalescence ahead of her, she was passing her days on the worn plaid sofa at a women's shelter in Agua Prieta by crocheting scarves for the staff.
Some would-be migrants have found alternatives. Daniel Cifuentes, a volunteer at a "migrant welcome center" right beside the border crossing, left his small coffee farm in the highlands of Chiapas a decade ago when coffee prices dropped so low it no longer supported his family. When he got to the border, though, Cifuentes was too frightened to cross and instead went to work in a maquiladora, an American-owned factory in Agua Prieta.
Eventually, he and others from his village set up a coffee roasting plant in Agua Prieta with help from Fronteras de Cristo, a Presbyterian Church group. They got their families and friends in Chiapas to organize a co-op and, with help from the church group, market their "fair trade" coffee in the United States. The enterprise now provides a living for 35 families in Chiapas and six more in Agua Prieta.
Cifuentes now helps others who have arrived at the border exhausted and bewildered. When he learned from Mexican officials that they were detaining 16 Guatemalan migrants to bus them 1,800 miles back to the Guatemalan border the next day, he and other volunteers heated a couple dozen thin bean burritos and delivered them to the jailed migrants. The men converged eagerly on Cifuentes and the food.
"I'm glad I can offer them something," he said. "They've come so far. I know how they're feeling."
At the Holy Family shelter, Valenzuela, the mariachi, accepted a towel and toothbrush from a volunteer and stowed his small bag of belongings on a bunk.
"I can't find much work as a musician in Mexico," he said. "But I can sell clothing and food, get a little work as a vendor."
Illegal immigration since the 1990s
The number of people who enter the United States annually without authorization has not grown substantially in recent years. What has changed, as border enforcement has increased the past 15 years, are the migration routes and difficulty of crossing -- and how long illegal immigrants stay.
Many of the migrants who used to return to Mexico for part of each year are staying in the United States because crossing illegally has gotten harder.
"It's like a bathtub: The same flow is going in, but the Border Patrol has really clogged up the drain, so the tub starts to fill up," said David Spener, a sociologist at Trinity University in San Antonio.
Each year this decade, the country has gained about 525,000 new illegal immigrants, up slightly from 500,000 annually in the 1990s, according to Jeff Passel, a demographer at the Pew Hispanic Center in Washington, D.C. An estimated 800,000 illegal immigrants arrive annually, up slightly from 750,000 a year in the 1990s. Throughout the period, about two-thirds of the illegal immigrants who arrived each year stayed in the United States.
Roughly 60 percent of illegal immigrants have crossed the border illegally; the rest entered legally and overstayed temporary visas, according to Passel, whose estimates of the undocumented population are considered authoritative by federal immigration authorities and researchers across the political spectrum.
Of the estimated 11 million undocumented immigrants in the country in 2005, Passel estimated that 6.2 million were from Mexico and another 1.4 million from Central America.