Well but the key word there is "somebody." If there was a single, all-encompassing, global world government that forced all fishermen to do this, then yes, we'd have a problem. If the United States (for example) caused its fishermen to do this, then the people of the United States would be well-advised to change this law, else they'll soon be out of fish. But even if they didn't, it's still not a question of "forcing" or "rights." Fishermen would simply fish elsewhere; at great cost, perhaps, with a loss of opportunity, no doubt, but it's still a question of choice.