If it were me...and it's not, I would circle about 25 or 30 predator's around that area of the ocean and launch hellfire missiles until the terrorist pirate types called “Calf Rope”.
I mean really, it can't be that difficult to sink small craft that are approaching shipping lanes.
Hellfires wơuld be a terrible waste of money. One or two .50 cal rounds per boat should be sufficient with few .308s for the flotsam left by the submerging vessels.