Some are doing processing, while others are manning communications, sensors, and other gear. That leaves at most 45 to actively patrol. The real fallacy is to think in terms of linear miles. It should be thought of in square miles.
The Naco station's primary patrol area is about 238 square miles. The secondary extends out to 510 square miles. Most of this area has terrain far more favorable to the illegals than the agents. That -- and our milder climate -- makes it easy to understand why almost 25% of illegal aliens use this small area as their fence-jumping point.
Let's say two groups of 30 to 50 illegals are spotted early in the shift. Depending on where they are spotted, it will require 8 to 12 agents to round up each group, transport them back to the BP station for processing, and stick them back through the gate. Suddenly, half the agents are tied up for a couple of hours and a big chunk of the border is wide open and unguarded. The coyotes aren't dumb; this is when they push the bulk of their clientele through.
If you go to this link right now, you can watch part of tonight's action as it goes down.
Post #49 tells the facts from a man who KNOWS what he is talking about. He has aided the BP in gathering up illegals for deportation for A FEW YEARS.