Earlier today US President Barack Obama traveled to Midway Atoll, located off the coast of Hawaii, to celebrate the expansion of the Papahanaumokuakea Marine National Monument, a marine protected area (MPA). The monument's expansion will permanently protect pristine coral reefs, deep sea marine habitats, and important ecological resources in the waters of the Northwest Hawaiian Islands. It's an important step in global marine conservation.

The monument was initially declared by President George W Bush in 2006 to cover the ten islands and atolls of the Northwest Hawaiian Islands. The recent expansion extends the monument by about 350% to include most of the exclusive economic zone (EEZ) around the islands. The expansion is in response to strong political pressure from the marine conservation movement in the US, as well as from prominent Hawaiian leaders concerned about the interests of native peoples in resource management.

The US is legally entitled to declare this monument within its EEZ. But is the claimed EEZ around the Northwest Hawaiian Islands in accordance with international law? This question has been broached as a result of the recent ruling by an arbitral tribunal in The Hague that there are no 'fully entitled' islands in the Spratly island chain in the South China Sea entitled to an EEZ and continental shelf.

An 'island' is defined in Article 121 of the 1982 UN Convention on the Law of the Sea (UNCLOS), as 'a naturally formed area of land, surrounded by water, which is above water at high tide'. This article goes on to specify a criterion that if such offshore features 'cannot sustain human habitation or an economic life of their own', they are 'rocks', and entitled to a territorial sea only. If they are able to meet that criterion, they are 'islands' entitled to a full set of maritime zones, including a continental shelf and EEZ.

The judges in the recent ruling took a narrow interpretation of an insular feature's ability to 'sustain human habitation or an economic life of their own'. Their criteria rested on a feature's ability to provide a naturally occurring supply of food, water, or shelter in quantities sufficient to enable a group of persons to live for an indeterminate period of time. They considered that any past economic activity was purely extractive in nature and were unimpressed by any history of habitation.

The ruling has far-reaching implications. It presents challenges for other countries, including Australia, Japan and the US, which have claimed a full set of maritime zones from small, isolated features. Those countries are all likely to ignore the precedent established by the ruling on 'rocks' and 'islands'. Japan has already reasserted that the small feature of Okinotorishima in the Pacific Ocean, from which it claims both an EEZ and an extended continental shelf, is a true island rather than a rock.

The Northwest Hawaiian Islands stretch about 900 nautical miles from Midway and Kure Atolls to Nihoa Island. Using the precedent established by the recent arbitral ruling, of the ten islands and atolls comprising the Northwest Hawaiian Islands, only three at the most (Midway Atoll, Laysan Island and French Frigate Shoals) would likely be accepted as 'fully entitled' islands. The other features would probably be regarded as 'rocks' entitled only to a 12 nautical mile territorial sea.

The US is unlikely to be too fussed about these implications of the ruling. The EEZ around the Northwest Hawaiian Islands has been in place for many years without any protest from another nation (unlike the Spratlys, which attract controversy due to the conflicting sovereignty claims and the impact of their status on maritime jurisdiction in the area).

Similar considerations apply to Australian islands (such as Heard Island and McDonald Island in the southern Indian Ocean, and Mellish Reef in the Coral Sea) whose status might be questioned in the light of the arbitral ruling. However, these islands have all been used as basepoints in maritime boundary agreements with neighbouring countries. This helps substantiate the status of these features as 'fully entitled' islands.

Countries often introduce new maritime regulations that could be regarded as contrary to the customary international law of the sea. This is particularly the case with the EEZ, which is a carefully balanced regime protecting the rights and duties both of the coastal state and of other states.

Despite frequently asserting that high seas freedoms of navigation apply in an EEZ, the US has introduced regulations in its EEZ that have the impact of restricting freedom of navigation. It has, for example, introduced legislation in its Oil Pollution Act 1990 (OPA 90) that restrict tanker operations in its EEZ, as well as mandatory speed restrictions in parts of its EEZ to reduce the threat of ship collisions with North Atlantic right whales.

Australia is also open to similar criticisms. Despite its concern for freedom of navigation, it has introduced restricting measures, such as compulsory pilotage in the Torres Strait, and mandatory ship reporting in parts of the EEZ adjacent to the Great Barrier Reef.

The bottom line is that countries will pick and choose when it comes to following rules and precedents. Politics invariably comes into play. The law of the sea is a moveable feast, with environmental concerns being the main drivers of new regulations that depart from existing norms.

 Photo: Flickr/USFWS - Pacific Region