The U.S. Border Patrol has assigned more agents to the Southern California coast following an increase in attempts to smuggle people and drugs into the United States by water, a Border Patrol official said.
The agency's San Diego Sector, which employs some 2,600 agents to police 60 miles (96 km) of land border and 114 miles (183 km) of coast, has seen maritime apprehensions triple in the past five years while arrests on land have dropped to less than a sixth of 2008 levels.
"We have increased staffing along the coast and we are working with Customs and Border Protection to beef up our assets along the coast," San Diego Sector Chief Paul Beeson told Reuters in an interview. "We see the threat there increasing and we are significantly increasing our presence."
In the past two years, agents have apprehended some 1,300 people, seized more than 200 vessels and recovered more than 135,000 pounds (61,235 kg) of drugs along the coast between the Mexican border and Rancho Palos Verdes, Border Patrol spokesman Steven Pitts said.
In 2008, by comparison, there were 230 apprehensions, 33 vessels seized and no drugs recovered, Pitts said
Crossing by water, which usually involves heading miles out to sea, running parallel to the coast and then coming back to shore, are dangerous. Since 2010, five illegal border crossers have died at sea, Border Patrol spokesman Steven Pitts said.
"The transnational smuggling organizations do not care about the human lives they put in danger," Pitts said. "We often find no safety equipment on the boats, or safety equipment that doesn't work properly."
In 2008, the San Diego sector recorded about 162,000 arrests on land, while the first 10 months of fiscal year 2012 yielded about 26,000 such arrests, Pitts said.
Authorities say the decline in arrests on land have been a result of "hardening the border" - adding miles of intensified border fences, as well as cameras and sensors - as well as a big increase in patrolling.
The Pew Hispanic Center released a study in April that cited the hardening of the border and the decimation of the job market - the main attraction for many illegal border crossers - as the main causes for the steep decline in illegal immigration.
Meanwhile, smugglers have taken to the sea, often in wide, open power boats called pangas carrying people or marijuana.
Last month a panga launched in Mexico and loaded with pot rammed a U.S. Coast Guard boarding party near Santa Cruz Island, killing one Guardsman and injuring another.
Pangas aren't the only vessels being used - Border Patrol agents routinely pick up single passengers dropped off by personal watercraft along the California coast near the border, officials said. They have also captured several mini-submarines.