A [Human science ship] is basically a prickly little echidna going through space wearing a mortarboard. It just wants to science. If you stop it sciencing, it can survive you kicking it, hurt the foot that you were foolish enough to use to kick it, and call for help from the other, decidedly LESS peaceful ships Humanity has to offer. -- RecklessPrudence
Humans are dangerous. Everyone knows this. The preferred method of interacting with humans, for the longest time, was simply two words. "Run away."
But there are always a few who believe that chasing their chosen employment is more important than long-term survival. Other Galactics referred to them as 'Edge-clippers'. Those who made their fortunes by skating along the very cusp of safety.
Gorqax didn't bother the human vessels he spied. He just insisted on doing his mining and salvage work where he could keep an eye on them as they went about their business. When he scanned them, or read their emissions, it seemed like they were doing science. They made no efforts to communicate with him, so he made no efforts to communicate with them.