MASSENA, N.Y. —  Most days, along a certain section of the St. Lawrence Seaway (search) that separates the United States from Canada, Dick Ashlaw and other U.S. Customs and Border Protection agents cruise the waters looking for terrorists, smugglers or illegal aliens trying to cross into New York.

Although Ashlaw said his team catches all the illegals crossing into the country that they see, it’s who the Border Patrol (search) doesn’t see that leaves Agent-on-Charge Ashlaw feeling uneasy.

"It is harder to catch people or terrorists or weapons of mass destruction up here than it is on the southern border," Ashlaw said, adding that there are far more border agents on the southern U.S. border — equipped with high-tech tools like sensors and cameras — than there are on the country's northern border.

"We are all crying for extra help ... every station on the Border Patrol wants more people," he added.

While FOX News was asked not to be specific about the numbers of officers and miles of territory Ashlaw and his men cover, Border Patrol agents have their work cut out for them.

Making this area even more difficult to patrol is a sovereign Indian reservation that spans across the border of both countries.

“That may be Canada, but it is part of the reservation, so they [illegal immigrants] can pass freely from one side to the other," Ashlaw said.

Click in the video box to the above right to view a report by FOX News' Todd Connor.

Ashlaw said that after the Sept. 11, 2001 (search) terror attacks, people in the area became more vigilant. And the Border Patrol has encouraged that vigilance by handing out business cards with contact numbers — telling people they could use extra sets of eyes to guard the border.

"What has happened is that the community and people in general are just being more observant and taking a part,” Ashlaw said.

Since Sept. 11, the number of Border Patrol agents along the northern boundary with Canada has more than tripled. But, “the thought here is you can never have enough,” Ashlaw said.

While arrests haven’t tripled, they are up in the area. The most recent statistics show that from 2001 to 2004, the number of illegal aliens taken into custody has gone up about 10 percent to 2,701.