Ah yes the difference between ships and planes.
As some might realize ships travel at very slow speeds,( most commericial vessels travel between 0 and 8 mph) and INS/Customs/Dept AG personnel require some 3 hour notice before docking its often impossible for the agents to fix a exact time for the "boarding parties" .
So very often there a bunch of people sitting on the dock waiting to go board.
I short we get to and do converse, sometimes at length with the officers. Over period you will get to know a lot about many of them.
mike