Migrant crossings at the US-Mexico border are down. What's behind the drop?

A recent decline in arrests for illegal crossings on the U.S. border with Mexico may prove only temporary. The drop in January reflects how the numbers ebb and flow, and the reason usually goes beyond any single factor.

After a record-breaking number of encounters at the southern border in December, crossings dropped by half in January, authorities reported Tuesday. The largest decrease seen was in the Del Rio sector encompassing Eagle Pass, Texas, the main focus of Republican Gov. Greg Abbott’s recent border enforcement efforts. Mexico also increased enforcement efforts during that time after talks with U.S. President Joe Biden's administration.

A look at the numbers and what's behind them:

WHAT DO THE NUMBERS SAY?

Overall, arrests by Border Patrol dropped in January by 50% from 249,735 in December, the highest monthly tally on record.

Tucson, Arizona, was again the busiest sector for illegal crossings with 50,565 arrests, down 37% from December, followed by San Diego. Arrests in the Border Patrol’s Del Rio sector, which includes the city of Eagle Pass, plummeted 76% from December to 16,712, the lowest since December 2021. Arrests in Texas’ Rio Grande Valley, dropped 60% to 7,340, the lowest since July 2020.

A significant decrease was noted among Venezuelans whose arrests dropped by 91% to 4,422 from 46,920. But those numbers could change soon. Panama reported that 36,001 migrants traversed the dangerous Darien Gap in January, up 46% from December. The vast majority who cross the Panamanian jungle are Venezuelans headed to the United States, with considerable numbers from Haiti, China, Ecuador and Colombia.

WHAT IS MEXICO DOING?

Mexico has been forcing migrants from freight trains that they sometimes use to cross the