Beyond the ballast water vector a few countries are serious about biofouling on the hull.
Had these Guys clean our hull before we could enter NZ waters a while ago. Quite the machine. The recovered water and matter flows over what looks like a shale shaker. The solids get swept into a super sack for disposal ashore. The liquid passes through what amounts to a BWTS (filter stage and UV stage) and overboard in the designated cleaning anchorage.
Thing was all cobbled together on a work barge with a small workboat ala American style of doing things.
If the market is there one could see purpose built small vessels with better material handling, diving support features, etc. Hell give Norway a chance and it will have an x-bow, Hilton accommodations and Michelin star quality food. But I digress.
Aside from the IMO guidelines some places have actual laws / regulation in place. Which is what got us.
Right now it means the chief mate and I have yet another record book to keep up and more inspections added to the CMMS system.
Don’t get me wrong invasive species are a threat with economic consequences but yet another patchwork approach and unrealistic goals without supporting technology or methods but all the consequences for shipboard folk is getting wearisome.