Mexican workers leaving the United States in response to heightened immigration enforcement will be missed in the coming decades as millions of baby boomers retire, a Mexican consul said Aug. 7 at Thunderbird School of Global Management.

“The departure of Mexican workers isn’t necessarily good news for the American economy,” said Carlos Flores Vizcarra, the Mexican consul general in Phoenix. “Within 30 years, nearly 77 million Americans will retire. So the question is, who will take the place of those folks who are retiring?”

He said people who assume that Mexican workers can be invited back at any time need to look at the demographic projections. Mexico’s population is already stabilizing after decades of rapid growth, and Flores said the country will experience negative population growth by 2040.

“Mexico will not be a never-ending source of human beings,” Flores said. “There will be shortages of labor in Mexico.”

His comments came during a presentation on “The Future of NAFTA in a Sagging World Economy,” which Flores delivered to a group of about 50 international graduate business students in Glendale, Ariz.

Flores said the North American Free Trade Agreement has boosted productivity and trade in Mexico, the United States and Canada since its implementation in 1994. But lagging wage growth in Mexico — along with the population surge — have spurred increased immigration to the United States.

He called the Mexican population explosion a “stampede” or “fiesta loca” that started in the 1940s, when the United States sent its young men overseas to fight in World War II and looked to Mexico to help fill the void in the labor market.

Back then, he said, Mexico only had about 18 million citizens. Today, an estimated 20 million foreign-born residents of Mexican descent live in the United States — more than the entire population of Mexico at the start of World War II. Overall, Mexico’s population has more than quintupled to about 107 million citizens.

“It is like a revolution that no country could have digested,” Flores said. “What has been our safety valve? The U.S.”

But the trend has started to reverse itself. Flores said the sluggish U.S. economy and stricter immigration enforcement have prompted many Mexican workers to return home.

Already, he said, an estimated 10 percent to 11 percent of undocumented workers in the United States have returned to their countries of origin. This figure is closer to 18 percent in Arizona.

Flores said many of these workers are heading to Canada, where new opportunities have emerged.

“Canada is pressing on Mexico so that Mexico can provide more labor to Canada,” he said. “From this moment, Mexico is looking to the Canadian horizon, maybe with more interest than to the U.S., basically because of the sluggish economy here in America, and also because Canada is discovering new economic frontiers in Manitoba and Alberta.”

He said Canada will benefit from these arrangements. Overall, he said, the need for North American cooperation has never been greater as globalization accelerates.

“We are facing tremendous competition,” he said. “The development of a North American consciousness will likely produce a common front in the face of other alliances, such as China and India.”