LOURDES GARCIA-NAVARRO: For more than six decades, one fact about the U.S. southern border has been remarkably consistent - migrants caught crossing it were more often from Mexico than anywhere else in the world. But that has now changed, according to the Pew Research Center. In 2014, for the first time on record, more non-Mexicans were caught than Mexicans. We're talking 30,000 more. And here to talk about that shift and what's behind it is Jeffrey Passel, a Pew senior demographer and one of the authors of the recent study. Thank you so much for joining us.
JEFFREY PASSEL: I am glad to be with you.
GARCIA-NAVARRO: So, I mean, this is a pretty important shift. It's important to note, of course, that Mexicans still make up the biggest percentage of illegal immigrants actually in the U.S. That said, less of them than ever are coming over the border. Why?
PASSEL: Well, the U.S. economy isn't generating the kinds of jobs that have attracted Mexicans in the past. The increase in enforcement along the border has made it both more dangerous and much more expensive for Mexicans to get in. And then on the Mexican side, things are doing better in the Mexican economy. As a result of historic drops in fertility, there are actually fewer Mexicans in the prime migrating ages. And then in northern Mexico, the drug cartels have made it very dangerous for Mexicans to cross towards the border. So it's really a combination of factors that have come together.
GARCIA-NAVARRO: In your study, you note that we're seeing a lot of Central Americans coming over instead. Of course, this year we saw the crisis with unaccompanied migrant children from that region. Was that the reason for the spike in Central Americans?
PASSEL: That was only part of it. The Central Americans have been increasing in the unauthorized population. The unaccompanied minors are a part of this increase, but actually a rather small part. It's been a multi-year trend of about four or five years where the numbers have just been going up steadily.
GARCIA-NAVARRO: One of the things that really caught my eye though was how the number of non-Hispanics has jumped. Where are we seeing people coming from outside of this region?
PASSEL: Well, in terms of the unauthorized population, we're seeing increasing numbers from India, increasing numbers from China - are the two major sources in Asia. But we've seen small increases in the unauthorized population from basically all parts of the world, really, except Mexico.
GARCIA-NAVARRO: So what do you think is so important about the shift? What is it saying about illegal immigration and where people are coming from?
PASSEL: Well, the fact that the Mexican unauthorized population has dropped and that the number of people trying to sneak in across the southern border are at historic lows suggest that there has been a fundamental shift, and that enforcement of the border seems to be working in that the numbers have gone down quite a bit. Apprehensions at the border of Mexicans were about 1.6 million in 2000. And this past year, it was 225,000. And the number of Mexican unauthorized immigrants living in the U.S. has continued to go down. The rhetoric around unauthorized immigration doesn't seem to have changed, yet the patterns have altered dramatically just within the last five years.
GARCIA-NAVARRO: Jeffrey Passel is a Pew Research Center senior demographer. Thank you so much for joining us.
PASSEL: You're welcome.