– As law enforcement stops go, this one was low key.

Three U.S. Border Patrol agents were paddling the fringe of this 1.1-million-acre wilderness when one agent, Matt Curran, 46, waved in the direction of a canoe angling south on Saganaga Lake.

Curious what Curran and his canoe mate, fellow agent Jorge Gomez, 48, might want, the southbound paddlers changed course and soon were alongside the agents’ canoe.

Nearby, in the bow of a canoe with me, was agent Brandon Law, 34. I had been allowed to accompany the officers into the wilderness to observe their work, which the Border Patrol is expanding along Minnesota’s northern boundary with Canada.

Curran, Gomez and Law wore life jackets, which obscured the badges on their shirts. So even from a short distance away they appeared to be run-of-the-mill BWCA canoeists.

But close up, their holstered .40 caliber Heckler and Koch P2000 handguns were giveaways that the men weren’t typical wilderness travelers.

“Good morning, U.S. Border Patrol,” Curran said to the two paddlers. “Where are you coming from?”

• • •

If the agents had said they were aliens from a distant planet, the canoeists wouldn’t have been more surprised. Or so it seemed by the looks on their faces.

But that question — “Where are you coming from?” — is being asked more often in the boundary waters these days by U.S. Border Patrol agents.

Headquartered in a cramped building in Grand Marais, Minn., whose garage has been converted into a weightlifting room, Curran, Gomez and Law are among a growing contingent of Border Patrol agents assigned to that station who regularly fan out into the wilderness, sometimes traveling by canoe and other times by foot, motorboat, four-wheeler or, in winter, snowmobile.

Three Border Patrol agents also recently have been assigned to Ely, part of a network of officers stationed along the nation’s northern border, from Maine to Washington state.

Some agents, like those posted to the more open landscapes of North Dakota or Montana, patrol in vehicles or occasionally in airplanes. But vast wilderness areas, such as the one extending along Minnesota’s northern border, present unique enforcement challenges, requiring the agents to quickly learn new outdoor skills.

A native of west Texas, Gomez moved to Grand Marais with his wife and 11-year-old son last October. Curran has been in town almost three years. Originally from Massachusetts, he’s married with two teen-age children. And Law, who grew up in Idaho, has been in Grand Marais about a year with his wife and three young kids.

None of the three agents had been to northern Minnesota before being assigned to the Grand Marais station, which was first established in 1924.

The agents say the U.S.-Canada border doesn’t present the same types of threats, or volume of threats, as the nation’s border with Mexico. But their basic responsibilities are the same: Prevent undocumented people, drugs and other contraband from getting into the country.

Especially terrorists and terrorists’ weapons.

“Our assignment in the north is different in some ways than on the southern border, but we still have to be vigilant,” said Curran, the agent in charge in Grand Marais.

Added Law, the station’s supervisory agent and a lawyer:

“Criminal organizations are always probing and looking for deficiencies and inabilities of law enforcement. It’s incumbent upon us to be aware of who these people are, what they’re doing, and what they’re thinking about doing.”

Nearly all Border Patrol agents serve their first assignments on the southern border, where snakes, tarantulas, scorpions, fire ants, prickly cactus and illegal transients from the south — some armed and carrying backpacks full of drugs — are routinely encountered.

Where Gomez worked, in west Texas, rattlesnakes were a constant problem. But Curran was deployed in a different part of that state, along the Rio Grande, where farmers regularly dumped pickup loads of blacksnakes into their fields.

Blacksnakes kill rattlesnakes, allowing farmworkers to pick crops without being bitten.

“If you talk to 20 different agents, each will have a different experience on the southern border,” Curran said. “We have agents down there on dirt bikes, horses, ATVs and in helicopters.”

Foremost among skills agents learn in southern Texas, New Mexico, Arizona and California is how to “cut sign.”

“Where I worked in Arizona, you might be out at night, patrolling alone or with another agent, and you’re looking for ‘environmental disturbances,’ ” Law said. “The sign you see might be that of animals traveling, or it could be people traveling. You need to be able to tell the difference, because people coming across the border often will strap carpet to their shoes to hide their footprints.”

The illegals, Curran said, might have jumped a border fence by placing a ramp on it. Or perhaps they cut a hole in the fence or drove through it with a vehicle. Regardless, their goal is to travel north as quickly as possible. Some will be met by cooperators at the nearest freeway. The drugs might go one way, to a safe house for later distribution, and the people another way.

“They have cellphones and are in contact with one another,” Curran said.

On Lake Saganaga the other day, the two paddlers Curran and Gomez encountered represented no threat whatsoever. They hadn’t been to Canada, and instead had paddled only on the Minnesota side of the boundary waters.

The encounter was friendly.

“OK, thanks a lot,” Curran told them. “Have a good day.”

The agents’ intent, Curran said, isn’t to hassle wilderness visitors, or even disturb them.

“But we do want to explain to people who travel into Canada that there are certain things they have to do when they come back to the U.S., like check in with the nearest Customs office, or with our office in Grand Marais, if we’re open, or possess an I-68 form that they’d received previously from Customs and Border Protection, ” Curran said. “They also should have their passports. There’s a border here, and we want to make sure the people coming into our country are supposed to be here.”

• • •

On an island campsite big enough for four tents, and open enough to allow breezes to waft through the shoreline’s statuesque pines, Gomez, Law, Curran and I started a campfire.

Boat traffic had slowed to a trickle on Saganaga, a giant lake straddling the U.S.-Canada border, and from our campsite the agents, using powerful binoculars, could watch the lake

People, Curran said, commonly mistake the Border Patrol for U.S. Customs and Border Protection. Both are part of the Department of Homeland Security. But both have distinct responsibilities.

“We’re not the guys in the booth at the border,” Curran said. “Sometimes we might be at a port of entry and commonly are on the southern border. But generally we’re mobile and operate between ports of entry.”

Another difference: Customs and Border Protection officers are located at all entry ports, including inland ports, such as at Minneapolis-St. Paul International Airport. With some exceptions, the Border Patrol places its agents only on the nation’s northern and southern borders, leaving the east and west coasts to be patrolled by other agencies and the Coast Guard, which is also part of Homeland Security.

Gomez, Curran and Law are never truly off duty when traveling in the boundary waters. So that evening, when they and I pushed away from shore in our canoes to end the day fishing, they still had their handguns strapped to their hips, and their binoculars nearby.

Their Minnesota jobs, the three men say, have been a good fit. The people of Grand Marais have welcomed them and their families, and they’ve become part of that community.

Still, few experiences say Up North like a smallmouth bass exploding from the depths to hit a popper or floating crank bait.

On this day, smallmouth bass were doing just that, snapping, as were northern pike, each striking surface lures cast into shallow water sometimes only a foot or two deep.

Alert to these environmental disturbances, Curran, Gomez and Law cast, and cast again.