By RANDAL C. ARCHIBOLD
TOHONO O’ODHAM NATION, Ariz. — A fresh footprint in the dirt, fibers in the mesquite. Harold Thompson reads the signs like a map.
They point to drug smugglers, 10 or 11, crossing from Mexico. The deep impressions and spacing are a giveaway to the heavy loads on their backs. With no insect tracks or paw prints of nocturnal creatures marking the steps, Mr. Thompson determines the smugglers probably crossed a few hours ago.
“These guys are not far ahead; we’ll get them,” said Mr. Thompson, 50, a strapping Navajo who follows the trail like a bloodhound.
At a time when all manner of high technology is arriving to help beef up security at the Mexican border — infrared cameras, sensors, unmanned drones — there is a growing appreciation among the federal authorities for the American Indian art of tracking, honed over generations by ancestors hunting animals.
Mr. Thompson belongs to the Shadow Wolves, a federal law enforcement unit of Indian officers that has operated since the early 1970s on this vast Indian nation straddling the Mexican border.
Tracking skills are in such demand that the Departments of State and Defense have arranged for the Shadow Wolves to train border guards in other countries, including some central to the fight against terrorism. Several officers are going to train border police in Tajikistan and Uzbekistan, which border Afghanistan, and in several other countries.
In the renewed push to secure the border with Mexico, the curbing of narcotics trafficking often gets less public attention than the capturing of illegal immigrants.
But the 15-member Shadow Wolves unit, part of Immigration and Customs Enforcement, is recruiting members to reach the congressionally authorized complement of 21. And the immigration agency is considering forming a sister unit to patrol part of the Canadian border at the Blackfeet reservation in Montana, where concern about drug trafficking is growing.
“Detecting is one thing, and apprehending is something entirely different,” said Rodney Irby, a special agent in Tucson for the immigration agency who helps supervise the Shadow Wolves. “I applaud the technology; it will only make the border more secure. But there are still going to be groups of people who penetrate the most modern technology, and we need a cadre of agents and officers to apprehend them.”
The Shadow Wolves have seized nearly 30,000 pounds of illegal drugs since October, putting them on pace to meet or exceed previous annual seizure amounts. They routinely seize some 100,000 pounds of illegal drugs a year, Mr. Irby said.
They home in on drug smugglers, who use less-traveled cattle tracks, old wagon-wheel trails and barely formed footpaths to ferry their loads to roads and highways about 40 miles from the border.
The Tohono land, which is the size of Connecticut and the third-largest reservation in area in the country, has long vexed law enforcement. Scores of people die crossing here every year in the searing, dry heat of summer or the frigid cold of winter. And its 76-mile-long border with Mexico, marked in most places with a three- or four-strand barbed-wire fence that is easy to breach, is a major transshipment point for marijuana, Mexico’s largest illicit crop.