It is a strange pastime, but I’ve been looking at nautical charts lately. They are full of cryptic symbols and squiggly lines, all of which have a deeper meaning for those willing to take a close look and do a little research. Those mariners who manage to keep their vessels off the rocks recognize the symbols representing the aids to navigation and the soundings. But what about some of that other stuff. What exactly does that gray line interrupted by little fishies represent? The three nautical mile line and twelve nautical mile territorial sea line are also gray, and their meaning seems self-explanatory, but what exactly is their significance. Call me a nerd, but I looked it all up.
The gray line interrupted by little fishies between St John and Tortola marks the Exclusive Economic Zone. Typically this extends 200 miles out to sea from the coastal state, but when neighboring nations are close together, they draw a line down the middle and call it a day. In this situation, the British have economic dibs on everything to the right, and the Americans have economic dibs on everything to the left. This 200-mile line is a big deal and changed almost overnight in the mid-1970s by a UN resolution. Before this, commercial fishing vessels would travel across oceans to fish close to the shores of distant nations. A problem because there was no practical way to enforce fishing limits and maintain sustainable fisheries. A surprise to me, but there was widespread if not universal agreement. Perhaps nations that did not gain from a fisheries standpoint saw it as a way to keep foreign oil rigs from springing up off their coast, but that is speculation on my part.
Also by UN agreement, the territorial sea extends 12 nautical miles from the shoreline of a coastal State. Within this zone, the coastal State has full sovereignty and may legislate on matters as they see fit without obligation to make these rules compliant with international standards, other than allowing the innocent passage of surface vessels.
So what about the 3-mile line? In 1608, Hugo Grotius published in his book MARE LIBRUM the idea that the oceans belonged to all states equally. He supported the premise that all vessel have the right to navigate and fish without interference. He allowed for a territorial sea belt for self-defense of 3 nautical miles, which was about the maximum range of the cannons at the time. The use of the oceans for the next three and a half centuries was bound to this legal framework. Now, the 3-mile line marks the boundary beyond which we can empty our holding tanks without fear of being fired upon by cannons.