this runs at the level of paranoia seen in various other conspiracy theories. You'll be burning effagies on the steps of Parliament next.
Commercial shipping and others can be addressed directly - its a pretty small group, easily identified and well controlled. Recreational boats, not so much.
The various statements from Regional Councils, MPI etc to "boaties" (a broad church that covers everyone from the owner of a 4m tinny to the Gin Palace brigade) are communications to the largest un-unified group. That group is largely ignorant of the biology, the risks and the methods of con