I am smelling the PLAN and the CIA on a joint venture in an international hoax. I don’t think that is possible but we live in a corrupt world.
How to get rats to jump out the ship-— micro smoke and electromagnetic spectrum vibrations— useful today or lure them into an onboard freezer, and/or the much nastier warfarin bait, and some.... water (then you have to locate where they have died, or shortly will smell them...everywhere).
So- smoke/electro them out— and then stand on the dock with several spotters and marksmen, and pick them off with a 22LR. How US Navy used to handle the wharf rats on their hawsers trying to come on their ships— tied to the dockyards in Vladivostok (end of WWII). Dad said they were the size of small cats— really, ugh.