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Exclusive Economic Zones
Guest Column by Muncel Chang, Department of Geography, Butte College (California)

Dateline: 11/07/00

Acquiring the desired resources for survival is an underlying theme in human existence. Societies and communities have always attempted to ensure a sustainable supply of food, water, and shelter. Depending upon where they are located, these groups have developed codes of behavior that we today have placed into "law." The areas occupied by humans have been strictly controlled, even by those groups whom we might consider as "primitive."

Before considering the global control of exclusive economic zones (EEZ) with regard to ocean jurisdiction, it might be worthwhile to examine an example of how one ancient society dealt with a similar situation on land.

In pre-contact Hawai‘i (before Captain James Cook "discovered" Hawai‘i in 1778), the islands had a system of land division called the ahupua‘a system. According to this system, each island was divided into elongated parcels that extended inland from the ocean to the mountains. Most ahupua’a did not extend all the way to the summits of the mountains, but went inland to about the 2500 or 3000-foot elevation, with some as high as 6000 feet. The size of an ahupua’a varied from a few hundred to several thousand acres and may have contained one or more subdivisions. The lower end of an ahupua’a is bounded by the ocean. The lateral boundaries of each ahupua’a were generally a natural landscape feature such as a stream, gulch, or ridge that ran inland from the coast. In areas where such physical features were not readily apparent, long stone walls were erected. The boundary markers were heaps of stones (ahu) with the image of a pig (pua‘a) mounted on the top that represented the tax or tribute paid to the Hawaiian chief of the region. The ahupua’a was "owned" by lesser chiefs who oversaw the families who lived and worked on the land. The main purpose of this system was to provide a local chief with a sustainable community, one that had ready access to the resources of the sea, the lowlands, and the uplands. The communities living in that ahupua’a shared in the tasks and responsibilities of land use. Laws and taboos (kapu) controlled the utilization of products and resources. Individual property ownership was not an issue. Thus a local Hawaiian community had fish, lowland food plants, upland crops, and forest products all within reach.

In lowland areas crops consisted of sweet potatoes, coconuts, breadfruit, and wetland taro (kalo, a root crop used for poi, a cooked paste-like food). Taro fields required running water. This crop was grown all year round. The fields also served as fish ponds for shrimp and small fresh-water fish. The fertility of these fields was constantly replenished by the irrigation water that came down from upland areas where crops like bananas, sugar cane, and dryland taro were grown. Upland areas also provided fruits like the mountain apple and timber for construction of everything from huts to canoes. Upland forests were also sources of decorative feathers from colorful birds.

Access to the sea was important for fishing, a primary source of protein. Pelagic, or deep sea, fish were an important resource for sustenance and trade. Where possible, shoreline fish ponds were also constructed for the raising of certain species, some of which were exclusively reserved for the royalty. Offshore fishing was restricted to the area directly fronting the ahupua’a and generally extended out to the reef or approximately a mile out to sea if there was no reef. The area available was also affected by the length of the shoreline available to an ahupua’a. If an ahupua’a had a narrow section of shoreline, their fishing rights were considerably limited. In some cases, an adjacent ahupua’a was very large and controlled offshore water that cut across the fishing area of its smaller neighbor. In such cases, the inhabitants of the smaller ahupua’a were limited to fishing in water that was "up to the neck" or "extending out not further than a man could touch bottom with his toes."

From the Hawaiian example, one can see that control of the land and sea resources is a complex issue containing compromises and solutions that are often based upon the relative power of all those involved. In similar fashion, control of the high seas has been a process of evolutionary development. It used to be based upon the relative power of the nation that had the strongest or most effective navy. To some extent, this is still true, but circumstances at the beginning of the twenty-first century have made it imperative that maritime nations develop a reasonable approach toward jurisdiction of ocean travel and resource development.

The control of the oceans is currently regulated by the 1982 Law of the Sea Convention that went into effect on November 16, 1994. This law defines oceanic jurisdiction for all nations. It establishes the principle of a 200-nautical-mile limit on a nation's exclusive economic zone (EEZ) whereby a nation controls the undersea resources, primarily fishing and seabed mining, for a distance of 200 nautical miles from its shore.

The diagram above shows a very simplified, basic outline of the important distance markers for the international zones of jurisdiction over the adjacent sea. The letter B is the low-water line along the coast and it represents the baseline from which all seaward measurements are determined. Be aware that international systems of measurement are according to the metric system. This also includes all international commerce. The original metric system was based upon commonly found Earth systems. The nautical mile was developed during the age of sailing and has become the international system for measuring ocean (nautical) distances. It is defined as one minute (1') of latitude or 1.15 miles. (A degree of latitude is approximately 69 miles; a minute of latitude is 1/60th of that.) That makes a nautical mile about 1,852 meters (6,076 feet) in length or 18% longer than a statute mile, the measurement commonly used in the English system (5,280 feet or 1,609 meters). Few Americans realize that their "frequent flyer" miles are calculated in nautical miles and not statute miles.

Prior to the 19th century, a nation's jurisdiction over the sea adjacent to its coastline was largely determined by the individual country's own criteria. This was based upon the concept of "effective occupation" or what a nation was capable of enforcing with the military resources at its disposal. The zone of control was determined by the distance that a cannon ball could be fired. Three nautical miles was the generally agreed distance, although that is a bit too far. Most 19th century cannons would do very well if they could reach a mile with any degree of accuracy. The old 3-mile limit is omitted from the chart above as it was generally replaced in 1967 by the 12-mile limit. Legal jurisdiction applies in relation to customs affairs, health concerns, and national security. The territorial water lying within the 12-mile limit is considered to be sovereign territory of the controlling nation, covered by the same legalities that apply to land. The primary exception is that all foreign ships are to be granted the "right of innocent passage." All ships, however, must be exposed and flying their nation's flag; no submerged vessels.

Military affairs are, for the most part, directly tied to a nation's daily concerns with its economic activities and in support of its economic security. The protection of ports, trade goods, and transportation services are of paramount importance. A maritime nation's economy also includes the fishing grounds of the shallow waters above the continental shelf along the coast. The development of undersea technologies with respect to seabed petroleum and mineral resources and the increased demands for seafood have made it necessary to update the laws governing maritime space. Many nations that border on the oceans of the world do not have the financial resources or military power to constantly watch over their adjacent sea. The Law of the Sea Convention of 1982 provides for a global understanding of what is considered to be a reasonable jurisdiction of the sea. Accordingly, all nations are held to a uniform standard of behavior that is universally agreed upon. The enforcement of this law then falls upon all international members who might bring their combined influence to bear on any violators.

The language used in all legal documents is critical to the issues and requirements contained in the document. Interpretation of a single word or term can be argued for centuries. Even when definitions are "clarified" and "exact," loopholes and differing perspectives always arise. One of the primary problems in regard to the Law of the Sea Convention of 1982 involves the definition of an "island." The law declares that an island is "a naturally-formed area of land, surrounded by water, which is above water at high tide." "Rocks" are excluded from this definition of an "island," but are included in another paragraph. "Rocks which cannot sustain human habitation or economic life of their own shall have no exclusive economic zone or continental shelf." Such rocks may still have a 12-mile territorial sea including a contiguous zone (24-mile limited jurisdictional zone), but no exclusive economic zone. The "loophole" lies in a nation's interpretation of what constitutes a "rock" vs. a "legitimate island." For example, if a "rock" is converted by enlargement and technology to support human habitation or to have an economic life of its own, is it then eligible to be re-classified as an "island?" It is not inconceivable to establish a producing well on a rock, build up a self-contained drilling platform complete with a hot-house or hydroponic facility, a desalination plant, and a solar-derived energy installation and call it an economically viable island. Any such "outrageous" or "illegal" measures being taken by claimant countries to "develop" a rock thus take on a whole new meaning. As an example fairly close to home, one might take a look at White, Chaffe, and Grissom Islands sitting just off-shore in Long Beach harbor. These are sophisticated oil drilling platforms in the guise of islands complete with palm trees and "high-rise buildings" that are, in reality, oil drilling rigs.

A current, on-going case involves a place called Sealand. During WWII, the British built a large concrete and steel platform fortress about seven miles off their east coast near Harwich. It was staffed and armed as an antiaircraft and naval outpost called Roughs Tower for the protection of shipping lanes leading into the Thames. Following the war, the platform was apparently abandoned and largely forgotten. In late 1966, a wealthy and eccentric former British army major, Roy Bates, "invaded" the platform claiming that it belonged to his ancestors. He brought out his family and set up residency. A year later he proclaimed himself to be Prince Roy with his wife, Princess Joan, as the heads of the new principality of Sealand and hoisted his own flag over his new "land." Apparently alarmed by these events, the British attempted to evict Bates, but were unsuccessful as the British courts held that Sealand lay outside the then 3-mile jurisdictional limit. By 1969, Bates issued his own passports, stamps, currency, flag, and constitution. He even has a national anthem. Over the years, several international incidents along with recognition by a number of nations have further tended to bolster the claim that Sealand is an independent country. The most recent wrinkle to this strange place is the business deal Bates has entered into with Sean Hastings, the head of an Internet company called Havenco. Outside of anyone's jurisdiction, Havenco is being set up as the "Switzerland of the Internet" where customers will be able to buy computer server storage space. Here individuals or companies will be able to run and carry on Internet transactions in secrecy, free from any outside interference. Construction and installation of computer equipment is already under way. There is some action being considered by the British government to counter the "total freedom" that has been allowed over the years. It remains to be seen what will really happen here as some think that Sealand might become a haven for various illegal activities. There are already indications that Sealand may provide duty-free shopping and a casino. The legal situation regarding this territory is still developing. For example, Sealand claims territorial waters out to a 12.5 nautical miles except where this claim overlaps with the claims of Great Britain. The question of Sealand claiming its own EEZ has not yet been addressed.

It is obvious from the above examples, that the designation of a “rock” as an island can amount to a great deal of benefit. Establishing an EEZ for even the smallest of islands can amount to several hundred square miles and result in enormous economic consequences. Such is the case for places like Kiribati (pronounced "key-ree-bas"), Hawai‘i, and the Spratly Islands.

Kiribati is a tropical Pacific island nation that lies almost due south of Hawai‘i. This group of islands straddles the International Date Line (IDL) and covers an east-west distance of 3,000 miles on and south of the Equator. It is composed of 33 small islands with a total area of 280.24 square miles. Twenty of these islands are inhabited by the nation’s population of slightly less than 100,000. On January 1, 1995, Kiribati unilaterally declared that the entire nation would no longer be split by the IDL but operate in the same day. The Kiribati day is now based in the Eastern Hemisphere even though more than 75% of the country is physically in the Western Hemisphere. In terms of an EEZ, Kiribati controls 1,370,300 square miles of ocean, an astounding 4,890 times its own land area!. This is the equivalent of more than 1/3 the land area of the United States. By comparison, Hawai‘i's EEZ covers approximately 550,000 square miles. This accounts for approximately 25% of the EEZ area controlled by the United States.

The EEZ of Kiribati may be changing. Two of its uninhabited islands, Tebua Tarawa and Abanuea, disappeared in 1999, covered with a rising sea level that has been attributed to global warming. The island of Tebua Tarawa was used by fisherman. It is also ironic that the island of Abanuea has a name that means "the beach which is long-lasting."

Other island nations are suffering the same fate. Beaches are eroding and islands are "sinking" in the Tropical Pacific, the Indian Ocean, and the Caribbean Sea. As they disappear, so do their exclusive economic zones. Concern over such losses have prompted nations to shore up threatened islands in an attempt to prevent their disappearance. A prime example of this is shown in the actions of Japan with regard to Okino-tori-shima (also known as Parece Vela) located 1100 miles southwest of Tokyo. Known as the "Island of the Offshore Birds," the island area is no more than a set of coral reefs. At high tide, only two "rocks" jutted slightly more than two feet (27 inches) above the waters of the Pacific. Typhoons annually ripped through this region and erosion threatened to submerge these rocks forever. Because these rocks commanded an EEZ of 154,452 square miles of very rich fishing waters, Japan could not allow this "island" to disappear. Spending millions of dollars in 1988, construction began to encircle the rocks with a wall composed of thousands of cast-iron tetrapods and concrete. This is similar to the breakwater barrier structures used at the mouths of harbors or as heavy rip-rap along river channels. The purpose was to break up wave action and prevent the washing away of the island. So far it has worked.

The importance of controlling a "rock" and its surrounding EEZ can be seen in the last part of the "Who Owns the Oceans" documentary (see the references). One quickly realizes that the claims and disputes in the Spratly Islands involve some very high stakes. For the countries involved, control of those islands may mean the difference between prosperity and poverty and between peaceful coexistence and war. Seeing military men occupying make-shift shacks on rocks or physically piling rocks upon rocks in an attempt to increase the size of and "island" may, at first, seem funny or ludicrous. It quickly becomes evident that this is serious business in international sovereignty and control.

Many questions still have to be addressed as these "island" problems gain in importance. Among them are the changing concepts of natural resource use. This involves the traditional concept of "ownership" as opposed to the rising concern of "stewardship." It is no longer sufficient to claim that because a nation has ownership of a region it can do anything it wishes with its property. In today's world, all actions have consequences that extend far beyond one's physical borders. Consideration is also required for the consequences that may affect future generations. The Law of the Sea Convention has been in effect for only a few years and its evolution is dependent upon continued international communication, reasonable interpretation, responsible development, and a good measure of self-control.


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Associated Press, "Acid, Dynamite Destroying Coral." Hawai‘i Tribune-Herald, May 6, 1998.

Bao-tian, Li, "The Physical Conditions and the Development of the Nansha Islands." Paper presented at the 1994 AAG Annual Meeting. (Li Bao-tian represented the Institute of Geography, Chinese Academy of Sciences, Beijing 100101, People's Republic of China).

Barraclough, Geoffrey, The Times Atlas of World History. Maplewood, NJ: Hammond Incorporated, 1979.

Boorstin, Daniel J., The Discoverers. New York: Random House, 1983.

Couper, Alastair, ed., The Times Atlas of the Oceans. New York: Van Nostrand Reinhold Company, 1983.

Cutler, B.J., "China's the Waterfront Bully of the Spratly Islands." The Sacramento Bee. July 27, 1994, B1.

De-xiang, Zhu, "The Geographical Discovery of the Nansha Islands." Paper presented at the 1994 AAG Annual Meeting. (Zhu De-xiang represented the Institute of Geography, Chinese Academy of Sciences, Beijing 100101, People's Republic of China).

Geographica, "Lonely Rocks Important to Japan," National Geographic Magazine, November, 1988 (Vol. 174, No. 5).

Glassner, Martin Ira, and Harm J. de Blij, Systematic Political Geography, 4th ed.. New York: John Wiley & Sons, 1989.

Ngok, Lee, "Taming the Dragon: Prospects for Genuine Cooperation in the South China Sea." Paper presented at the 1995 AAG Annual Meeting. ( Professor Lee Ngok is the Director of the School of Professional and Continuing Education at the University of Hong Kong).

Sea Power: A Global Journey, "Who Owns the Oceans," Program 5. New York: Ambrose Video Publishing, Inc., 1994.

United Nations "Ocean and Law of the Sea" homepage, http://www.un.org/Depts/los/index.htm

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