NOAA is responsible for depicting on its nautical charts the boundaries of the 12-nautical-mile coastal sea, the 24-nautical-mile contiguous zone and the 200-nautical-mile exclusive economic zone (EEZ). Each of these maritime areas is projected from a ”normal baseline” derived from NOAA nautical charts. A ”normal baseline” is defined under the law of the sea as the low water mark along the coast, as indicated on officially recognized large-scale maps, or the lowest date mapped, which in the United States means that it is low water (MLLW). The method for reaching this starting point is described in the 1958 Convention and the 1982 Convention. Normal reference levels in the United States are ambulatory and subject to changes such as accretion (adding land) and erosion. If the offshore boundary or area is not defined, it may change accordingly. The United Nations Convention on the Law of the Sea (UNCLOS), also known as the Convention on the Law of the Sea, is an international agreement that emerged from the Third United Nations Conference on the Law of the Sea (UNCLOS III), held between 1973 and 1982. The Convention on the Law of the Sea defines the rights and obligations of nations with regard to their use of the world`s oceans and establishes guidelines for business, the environment and the management of natural marine resources. The 1982 Convention replaced the 1958 Quadripartite Convention on the High Seas. The United Nations Convention on the Law of the Sea entered into force in 1994, a year after Guyana became the 60th country to ratify the treaty.  As of June 2016[updated], 167 countries and the European Union had acceded to the Convention. It is not clear to what extent the Convention codifies customary international law.
The Convention on the Law of the Sea requires that measures taken by States to combat pollution also include measures to protect habitats and ecosystems, but it does not explicitly call for cooperation in this regard or for ecosystem-based management of marine resources. The United Nations Convention on the Law of the Sea thus allows large marine ecosystems, which typically span two or more areas of jurisdiction, to be subject to potentially conflicting management approaches and standards of application. The protection of marine habitats is governed by two important international treaties – the 1975 Convention on Wetlands of International Importance, particularly as waterfowl habitat (Ramsar Convention) and the 1992 Convention on Biological Diversity – as well as several regional marine protocols and other regional agreements. The protection of marine ecosystems is much less developed in international law, largely because ecosystem science and management are themselves relatively new and underdeveloped areas. This circumstance could also be responsible for what some jurists consider to be an inconsistent approach to the protection of ecosystems in the Convention on the Law of the Sea. States also have rights to the seabed of the continental shelf. The continental shelf of a State is defined in UNCLOS as the natural extension of its terrestrial territory to the outer edge of the continental margin or 200 nm (approximately 370 km) from the baseline of the coastal State, whichever is higher. As a result, a state`s continental shelf can exceed 200 nm from its baseline until the end of natural extension. However, it should never be 350 nm (about 650 km) from the baseline.
The United Nations Convention on the Law of the Sea allows all coastal States to have the right to harvest mineral and non-living matter in the subsoil of their continental shelf (or to grant the right to others), to the exclusion of any other right. The practice of assigning the EEZ to nations and giving them control of maritime affairs outside territorial boundaries did not materialize until the end of the 20th century. In addition to the provisions establishing maritime boundaries, the United Nations Convention on the Law of the Sea establishes general obligations for the protection of the marine environment and the freedom of scientific research on the high seas. The United States opposed the provisions of Part XI of the Convention for several reasons, arguing that the treaty was unfavourable to American economic and security interests. Because of Part XI, the United States has refused to ratify the United Nations Convention on the Law of the Sea, although it agrees with the other provisions of the Convention. Article 62 proposes that, without prejudice to Article 61, coastal States promote the objective of making the best use of living resources in the EEZ. Overfishing or overfishing occurs when a fish stock has been caught below the size that, on average, would support the maximum sustainable long-term yield of the fishery. Overfishing can lead to resource depletion, reduced biological growth rates and low biomass content. Some forms of overfishing, such as shark overfishing, have disrupted entire marine ecosystems. The ability of a fishery to recover from overfishing depends on whether ecosystem conditions are suitable for recreation. These depleted fisheries can often recover if fishing pressure is reduced until the biomass of the stock returns to optimal biomass. At this stage, harvesting can be resumed close to the maximum sustainable yield (see Rosenberg (2003) and Grafton et al.
(2007). Overfishing affects not only the balance of life in the oceans, but also the social and economic well-being of coastal communities that depend on fish for their way of life. The Harvest Control Rule (UNHCR) proposed in 2011 to predict acceptable catches is based on a set of instruments and protocols that allow management to have some direct control over crop rates and strategies in terms of forecasting the state of stocks and long-term sustainable maximum yields (Froese et al., 2011). In general, there are two types of catch control rules: constant catches and constant fishing mortality (Fig. 8.3). 1973-82 Negotiation of the Convention on the Law of the Sea. The Convention will be concluded on 10 December 1982. Grotius` concept of ”freedom of the seas” became virtually universal during the 20th century after the global domination of the European maritime powers. National law and jurisdiction over the seas was limited to a specific belt of water extending off the coasts of a nation, usually three nautical miles (5.6 km), according to bynkershoek`s ”cannon shot” rule.  According to the principle of mare liberum, all waters beyond national borders were considered international waters: free for all nations, but not belonging to any of them.  The Convention set the limit for different ranges, measured from a carefully defined baseline.
(Usually, a baseline of the sea follows the low-water line, but if the coast is deeply indented, has fringed islands, or is very unstable, straight baselines can be used.) The areas are: Support the implementation of Sustainable Development Goal 14: Conservation and sustainable use of the oceans, seas and marine resources for sustainable development Figure 8.3. The concept of UNHCR. Notes: (1) The Convention on the Colour of Traffic Lights, which shows the concept of UNHCR and specifies when a reconstruction plan is mandatory with regard to precautionary and marginal reference points for spawning biomass and fishing mortality. (2) BPR and BLIM mean the preferred or limited spawning biomass; and FPR and FLIM indicate preferred or limited fishing mortality rates. The United Nations Convention on the Law of the Sea defines various maritime boundaries. For example, a reference line is defined as the line from which the maritime boundaries of the territorial sea of a State and certain other areas of maritime jurisdiction are measured. After UNCLOS, a maritime baseline follows the low-water line of a coastal State (see figure 9.2). The following methods are proposed to measure a baseline: President Reagan`s 1983 Ocean Policy Statement states that the United States will accept and act in accordance with the provisions of the Convention on Traditional (Non-Seabed) Uses of the Ocean, such as Navigation and Overflight. The high seas lie beyond the areas described above. The waters and airspace of this zone are open to all countries, with the exception of activities prohibited by international law (e.g.B. nuclear weapons tests).
The bottom of the high seas is called the International Seabed Area (also known as the ”Zone”), for which the 1982 Convention established a separate and detailed legal regime. In its original form, this regulation was unacceptable to industrialized countries, mainly because of its degree of regulation, and was subsequently comprehensively amended by an additional treaty (1994) to address their concerns. Under the amended regime, minerals on the seabed on the high seas are considered ”the common heritage of mankind”, and their exploitation is managed by the International Seabed Authority (ISA). Any commercial exploration or mining of the seabed will be conducted by private or public companies regulated and authorized by the ISA, although so far only exploration has been conducted. .