New Year's Day marked the start of a reduction in the number of moored surveillance balloons along the border, according to Customs and Border Protection.

Aerostats are designed to hover hundreds, if not thousands of feet in the sky, watching for activity on the ground and the air depending on the camera or satellite system it uses.

CBP operates multiple aerostats along the border from Puerto Rico to the California border. Among those, a cluster of seven watch over South Texas.

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Five of those are in the Rio Grande Valley.

From CBP's email Tuesday, it wasn't clear which aerostats are marked for demobilization.

"On January 1, 2023, U.S. Customs and Border Protection (CBP) began reducing the number of Tactical Aerostats deployed along the southwest border," said CBP spokesperson Rod Kise.

In Starr County and Western Hidalgo County, a string of four aerostats oversee the border.

Perla Bazan, who lives in La Casita, east of Rio Grande City, said she regularly hears foot traffic outside her home. She worries a drawdown would encourage illegal crossings.

“Removing the aerostats would greatly increase the danger we already have along the border,” Bazan said.

Maps published in 2017 from the Government Accountability Office showed the largest cluster of aerostats was in South Texas.

An agency spokesperson did not respond to follow-up questions about the rationale for the change or if aerostats in the Rio Grande Valley will be decommissioned.

In Tuesday's written statement from CBP, a spokesperson said the agency deployed 195 Autonomous Surveillance Towers, and plans to deploy another 80 of the systems.

CBP also reported adding 256 RVSS-U systems and 75 RVSS legacy sensor towers.