Unlike the waves of Mexican men heading for ``El Norte,'' most migrating women never cross the United States border. They rarely wade their way across the Rio Grande, weave their way through California canyons, or wedge into the trunk of a contraband car. Instead, tens of thousands of migrant women flock in to work at the 900 maquiladora factories dotting the US-Mexican border.
For that simple fact, Mexico is fortunate. During the past five years, its debt-ridden economy has foundered in red ink. But these young female laborers - who make up two thirds of the maquila industry's work force - have bullied the northern border region.
With nimble hands, passive work habits, and the lowest factory wages in the world, they have helped lure foreign firms to the borders thriving maquila or - ``in bond'' - industry. (Such export-oriented companies receive imported raw materials and components duty-free, and pay tariffs only on the value added to a product in Mexico.)
Their work also helps chip away at the country's $103 billion foreign debt. Last year, the industry garnered a record $1.28 billion in foreign currency earnings, propelling it past tourism into the second spot behind oil exports. And during the first five months of 1987, the maquila industry grew 8 percent in dollar terms over 1986, according to Mexican government statistics.
But for female factory workers in Mexicali and other border cities, the boom remains a mixed blessing. For the primary engine for growth, experts say, is the plunging peso, which has pushed Mexican wages one third lower than even those of Taiwan or South Korea.
For their often tedious labor, the young women - usually between 16 and 25 years old - earn little more than 50 cents an hour, not including benefits. ``It is really just a 2,000-mile long sweatshop,'' complains one Mexican economist, pointing out that comparable US workers make $12 an hour.
But at the same time, most workers seem satisfied to have a steady job that pays more than the minumum wage. According to a 1985 study by the Labor Congress, a coalition of Mexican unions, 56 percent of working Mexicans earn less than the minimum wage (41 cents an hour in the capital), and only 13 percent earn wages above the minimum.
Indeed, such jobs continue to draw female workers in droves. Thirty percent of the women workers are recent migrants who have arrived in the last five years, says Guillermina V'aldez de Villalva, a sociologist at the College of the Northern Border in Ciudad Ju'arez. Many of them migrate without their families.
They also come without previous work experience, according to Jorge Carrillo, author of ``Border Women in the Maquiladora Industry.'' The lack of family support and work saavy makes women particularly vulnerable, he says.
Not only are they often unaware of their rights, but they are disinclined to organize. ``The idea is that you can stop strong unions from entering your shop if you have a female work force,'' says Tijuana economist Bernardo Gonz'alez Arechiga, explaining one of the attractions for employers.
Businessmen in the maquila industry, however, scoff at that notion. ``Women just do these jobs better,'' says Ra'ul Garc'ia P'erez, president of the Maquila Industry Association of Baja California, referring to the ``light'' assembly work in the electronics and clothing factories.
Mr. Garc'ia points out that male workers are on the rise in the maquila industries. In the early years, soon after the US began its Border Industrialization Program in 1965, the assembly-floor workforce consisted of about 85 percent women. In 1986, as heavier industry arrived, women made up 66.5 percent of the 220,574 workers, according to 1986 Mexican government statistics.
``Women still are more conscientious, more punctual, more interested,'' says Garc'ia. ``Men don't like this kind of manual labor. They're more restless.''
But instability characterizes the work force, according to Guillermina Valdez. ``Job turnover is one of the most serious problems the industry faces,'' she says, noting that even women stay at their jobs for an average of only two years. Many leave to get married, have children, or find better opportunities, she says. But a disturbing number just grow tired of low wages and numbingly long hours.
``Women don't dare complain because they fear reprisal,'' says Francisca Sierra L'opez, a government social worker in Mexicali studying the maquila industry. Relaxing under a mimosa tree during a break in a two-day conference here on ``Women in the Development of the Northern Border,'' she notes that not a single maquiladora worker showed up at the event - even though they were invited and were, in fact, the center of discussion. It's more than fear, she says: ``Even the ones who have the will to speak up, often don't have the time because they have their husbands and their families.''