When is an island an island?

And why is this important? Professor Nele Matz-Lück tackled these questions in a lecture during Kieler Woche. In the unizeit interview, the Kiel international law expert explains why the definition of islands is so controversial.

unizeit: What is an island? And what is the difference between a rock and an island?

Nele Matz-Lück: An island is a natural elevation that projects out of the water at high tide. Rocks are generally not suitable for human habitation and cultivation. If people cannot live on a natural elevation, then there is much to suggest that it is a rock and not an island – size does not matter in this regard.

Why is this distinction important?

The world's oceans are divided into different zones. These are defined in the United Nations Convention on the Law of the Sea (UNCLOS) of 1982. Economically important are the exclusive economic zones (EEZs) and the continental shelf, which extend up to 200 nautical miles from the baseline – the low-water line along the coast of the state. In these areas, the respective state can economically exploit natural resources, such as gas, oil or fishing grounds. Mainland and islands can create these economic zones, but rocks cannot.

This sounds clear. Nevertheless, repeatedly, there are political conflicts about islands. Why is that?

It is the vague definition of islands, and above all, the elements mentioned in Article 121 (3) UNCLOS, which should differentiate a rock from an island. Even the statement that an island must protrude out of the water at high tide, raises further questions: What does high tide mean? Normal high tide? Spring tide? Which high tide are we talking about? Also the understanding that an island is only considered as such, if it can be lived on self-sufficiently, and otherwise is a rock, is going a bit too far in my opinion. In that respect, we also don’t live self-sufficiently on the mainland.

And you are interested in this because...?

The catalyst for my work was the prominent legal dispute between the Philippines and China over islands in the South China Sea. There was a ruling in 2016, in which China’s historical ownership claims to the Spratly Islands archipelago were declared invalid. The special aspect here was that the ruling includes a verbatim interpretation of the UNCLOS article on the definition of rocks, in order to distinguish them from islands. International maritime law has been waiting for this for a long time. With this ruling, the article is interpreted for the first time in a legally-binding manner between the parties. Accordingly, all elevations around the Spratly Islands archipelago are rocks at the most. Even if attempts are made to show that people can live there - for example, by constructing runways. In this case, however, the arbitral tribunal did not decide on the nationality of the archipelago, but only if there is a claim to an EEZ and continental shelf with the associated exclusive resource rights, or not. Who can assert their claim to the very profitable economic zone has not been determined. China rejects the arbitration ruling, and now the Philippines apparently too.

Are there other examples?

Taiwan, for example, claims Itu Aba, an elevation which also is part of the Spratly Islands archipelago. Substantial oil reserves are suspected here, as well as around the entire Spratly area. In order to prove that Itu Aba is a habitable island, and also that it belongs under Taiwanese control based on geographical proximity, the former President Ma Ying-jeou drank from a bottle on camera, which allegedly contained groundwater from Itu Aba. However, in accordance with tribunal ruling, Itu Aba is only a rock without any claim to an EEZ and continental shelf. The situation is different for France in the Southern Ocean. Here there are small, uninhabitable elevations, where there never was any doubt that they are islands. The lucrative zones around the islands have been exploited by France. After the ruling, this should actually now be fundamentally called into question.

So it has not become easier to differentiate islands from rocks.

In international maritime law, not just yet. There is still much work to be done.

The interview was conducted by Melanie Huber