Legally, what are the options?
At the lower end of the scale, could the OPV crew at the very least disable/destroy the winching equipment/nets to prevent further illegal fish catches (and thus force the vessels to return to home port)?
Could they destroy some of the windows on the bridge (making life uncomfortable for those sailing them and thus force a return to the home port)? Or would that ensue a "heath and safety" hazard?
It would be great if the OPV's could remove the fishing crews and sink the rust-buckets to prevent them returning, but environmentally wise that probably wouldn't be a good idea ... and it's not like NZ has a few heavy ocean going tugs to tow the vessels back to a NZ port.
Whatever happens I hope the pollies grow some balls and approve some form of action otherwise they will be back (ref link to the Michael Field
article via the Stuff article on the history of some of these vessels).