from COTUS
The Japanese boat should have yeilded the right of way by the rules of the road. Size matters but, as a vessel motoring in the open waters you are obliged to allow vessels on your starboard side to cross.\
Check your COLREGS International Regulations for Preventing Collisions at Sea 1972 Adopted and amended in 1977, 1981, 1989.
Rule 7(d)(i) "danger bearing" "Determining Risk Of Collision" (OBTW, they crossed in front of the whaler), in a deliberate provoking maneuver. Throws the give way thing out....
The whaler was clearly the "stand-on vessel" as the punk ass eco boys intercepted her course, changed her course and bearing several times, and in essence was buzzing the whaler as she was faster and more maneuverable.
Also general right of way provisions, pertain to commercial fishing vessels, vessels NUC (not under command or under tow), vessels under sail, or work vessels with restricted manuevering.
Plus there is the 22.5 degree rule abaft... There is also the Danger Bearing for even a give way vessel that the eco punks violated.
The rules of the road went out the door, The whaler also gave "five blasts" to avoid collision. Your Inland Waters & Great Lakes regs are sound but don't apply to International Waters.
Check your Chapmans, I have. Plus common sense says don't play chicken with a larger vessel. They did, and they lost.
The Officers on the whaler will have beers bought for them back in port.