Law of the Sea in Bay of Bengal Cases: Practical Difficulties of Grey Area for the Marine Environment

Moses Raj G S* | Sep. 13, 2020


United Nations Convention on the Law of the Sea (UNCLOS) disproportionately affects the developing world, given the history of colonialism and lack of technological advancement to enter seaward areas beyond national jurisdiction across deep seabed mining, marine scientific research, fisheries governance, ocean pollution, mineral extraction and biodiversity management. The law of the sea jurisprudence is still in its nascent form in South Asia. But because of the size and scope of the Indian Ocean, littoral states in South Asia and their extended relationship with the other Asian States have made UNCLOS an emerging field of inquiry and investigation, albeit, with few experts engaged in the field.

Given the uniqueness of the Bay of Bengal and its concave geographical and geomorphological coast, opposite and adjacent coastal states have the scope to make a separate submission on the outer limits of the continental shelf based on the provisions of the Statement of Understanding contained in Annex II to the Final Act of UNCLOS-III. The regime of outer continental shelf law in the Indian Ocean becomes even more important as states have partially submitted their claims of outer limits of the continental shelf to the Commission on the Limits of Continental Shelf (CLCS), or are in the process of submitting a separate submission, or are contesting the submissions made by adjacent or opposite coastal states.

Complexities of Outer Continental Shelf Regime

The International Court of Justice (ICJ) had stated in Nicaragua v. Colombia that information submitted to the CLCS according to Article 76(8) of UNCLOS will not necessarily be regarded as sufficient to establish the existence of an extended continental shelf. The court had also declared that ‘the definition of the continental shelf as set out in Article 76, paragraph 1, of UNCLOS forms part of customary international law. The area was further complicated by the International Tribunal for the Law of the Sea (ITLOS) in Bay of Bengal cases, which ruled that while the determination of entitlement to an outer continental shelf fell within ITLOS’s jurisdiction, any tasks relating to the identification of the outer limits belonged to the CLCS. However, the tribunal did not explain the evidence that a party seeking to establish an outer continental shelf must present to an international court or tribunal in order to prove its entitlement.

ITLOS further clarified that the delimitation test under Article 83 is based on distance from the coast and not on natural prolongation that is based on geological and geomorphological status. It proposed the innovative idea of  ‘grey area’ by differentiating water-column rights and continental shelf-rights causing practical difficulties of overlapping claims in the Exclusive Economic Zone (EEZ) and the high seas. However, Judge Rao in his partial Dissenting Opinion in Bangladesh/India, opined that ‘the sovereign rights of a coastal State over the water column and the seabed and its subsoil are considered as two indispensable and inseparable parts of the coastal State’s rights in the EEZ’. While UNCLOS is silent when the two overlap, the tribunal too, did not offer any guidance for the States concerned to deal with exercising of rights in the grey area. This is key to understand how tribunals appreciate scientific and technical evidence in contentious cases affecting marine environment at large with the creation of new sites of conflict. 

Practical Difficulties of a ‘Grey Area’

Lan Nguyen, in her Ph.D. thesis submitted to the University of Cambridge raises this conundrum of rights and obligations in a lengthy but critical question:

…supposing Bangladesh placed a mobile oil rig in the waters of Myanmar’s EEZ for the purposes of exploring and exploiting its oil resources in the seabed and the latter alleged that this oil-rig in conducting its activities on the seabed was causing pollution to its waters, would Article 208 relating to pollution from seabed activities or Article 211 relating to pollution from vessels apply? Article 208 meant that Bangladesh would have the jurisdiction over the vessel, while Article 211 would confer jurisdiction on Myanmar in accordance with Article 220. Likewise, India, under Article 60, has the exclusive right and jurisdiction over artificial islands, installations and structure in its EEZ. But supposing that the construction of those structures involved the dredging of the seabed, which damaged the living resources on the continental shelf of Bangladesh, which State would have enforcement power in this case?

International Marine Environment Law and Emerging Dynamics

ITLOS observed in the Southern Bluefin Tuna case that the conservation of living resources of the sea was an element in the protection and preservation of the marine environment. The Seabed Disputes Chamber in the Advisory Opinion on Activities in the Area examined the concept of responsibility and liability while expanding the scope of ‘obligation to ensure’ that the high seas are not exploited arbitrarily. According to the Chamber, responsibility is a primary and liability a secondary obligation, which would get activated upon the breach of the sponsoring State’s obligations towards conservation and management of the marine environment in areas beyond national jurisdiction.

In 2014, the ICJ expounded in Whaling judgment the duty to cooperate with treaty bodies in the conservation of highly migratory species. ITLOS, a year later in its Advisory Opinion on IUU Fishing reiterated that member states without distinction of flag states or coastal states had the general obligation of ‘due diligence’ under Article 192 regarding conservation and of marine living resources that occur both within the EEZ and in an area beyond and adjacent to these zones. Although, it did not specify the measures to be taken to satisfy the due diligence obligation thereby left it open-ended hoping the gap of interpretation will be filled through future state practice and litigation.

However, it was not until Chagos MPA and South China Sea casesthat Annex VII arbitral tribunals were able to deal with the legal rules relating to the protection of the marine environment. Despite the limited number of cases, ITLOS and Annex VII arbitral tribunal decisions have clarified broad operative principles under international environmental law namely: the precautionary principle, the duty to cooperate, the obligation of due diligence and the obligation to conduct an environmental impact assessment.

Misgivings of Exploitation Guidelines on the High Seas

The International Seabed Authority (ISA) has only provided exploration guidelines while awarding mining rights to states. As of 2019, a comprehensive mining code that describes exploitation rules and regulations by the ISA Council in its 25th session has made little progress. To be in conformity with UNCLOS Part XII, Member States of ISA in the negotiations process are emphasising on the incorporation of principles in the Rio Declaration and adoption of Regional Environmental Management Plans including a clear definition of the legal scope of obligations for states and pioneer contractors in the ongoing negotiations. Principles of environment and natural resources law must form the core of exploitation guidelines along with the existing exploration guidelines issued by the ISA. An investigation into the text of the negotiations of ISA should reveal why an attempt to codify exploitation guidelines is facing resistance from the developed States.

The inconsistencies in the law of the sea jurisprudence make it difficult to adopt a streamlined approach towards States’ activities that have considerable ramifications on the marine environment. This is evident in prompt release cases, advisory opinions and contentious cases. As States start deep seabed prospecting, irrespective of the success of their mining activities, the ISA’s exercise of jurisdiction and UNCLOS tribunals’ ability to adjudicate cases due to the lack of exploitation guidelines become restricted. These limitations will exacerbate the disputes in grey areas due to overlapping claims of EEZ and the freedom of the high seas while compromising on the conservation and management of the marine environment.


Grey areas and ocean spaces beyond national jurisdiction should be regulated with effective rules adopted through consensus. It must be ensured that marine resources – active and sedentary species are not disturbed or displaced due to commercial activities. As demonstrated in the Chagos MPA, South China Sea and Bay of Bengal cases, this is crucial in giving a progressive shape to the marine jurisprudence in Global South. To move from a narrow or fragmented interpretation to a more holistic understanding of marine environmental protection allows South Asian littoral States across the Bay of Bengal and the Arabian Sea shape their policies on the sustainable use of marine resources. This progressiveness will hold the South Asian States in good stead while advancing in the areas of maritime trade, hydrocarbon exploration, fisheries and marine scientific research in the Indian Ocean.

References :

  1. O P Sharma, The International Law of the Sea: India and the UN Convention of 1982 (Oxford University Press, 2009).
  2. Outer Limits of the Continental Shelf Beyond 200 Nautical Miles from the Baselines: Submissions to the CLCS by the Republic of India, available at (last accessed 1 September 2020).
  3. Question of the Delimitation of the Continental Shelf between Nicaragua and Colombia beyond 200 Nautical Miles from the Nicaraguan Coast (Nicaragua v. Colombia) (Preliminary Objections) 17 March 2016
  4. Delimitation of the maritime boundary in the Bay of Bengal (Bangladesh/Myanmar) (Judgment) ITLOS Reports 2012; Bay of Bengal Maritime Boundary Arbitration (Bangladesh/India) (7 July 2014)
  5. Bay of Bengal Maritime Boundary Arbitration (Bangladesh/India) (Award, Concurring and Dissenting Opinion of Dr. P.S. Rao)
  6. Lan Ngoc Nguyen, The Contribution of UNCLOS Dispute Settlement Bodies to the Development of the Law of the Sea, University of Cambridge – PhD thesis, (February 2018).
  7. Southern Bluefin Tuna (New Zealand v. Japan; Australia v. Japan) (Provisional Measures, Order of 27 August 1999) ITLOS Reports 1999, 280 [70].
  8. Responsibilities and obligations of States with respect to Activities in the Area (Advisory Opinion, 1 February 2011) ITLOS Reports 2011, p. 10 [23] [110].
  9. Whaling in the Antarctic (Australia v. Japan: New Zealand intervening) [2014] ICJ Rep 226 [83]
  10. Request for Advisory Opinion submitted by the Sub-Regional Fisheries Commission (Advisory Opinion, 2 April 2015) ITLOS Reports 2015, 4.
  11. Chagos Marine Protected Area Arbitration (Mauritius v. United Kingdom), Arbitral Award of 18 March 2015; South China Sea (Philippines v. China), Arbitral Award on the Merits 2017
  12. Summary of the Twenty-fifth Annual Session of the International Seabed Authority (Second Part), 25:207 Earth Negotiations Bulletin (29 July 2019).
  13. Bjarni Már Magnússon, The Grey Areas in the Bay of Bengal, July, 56 Indian Journal of International Law 41-58 (2016).

About the Author

Moses holds an LL.M. in International Law from South Asian University, New Delhi. He is currently an Assistant Professor of Law at St. Joseph’s College of Law, Bangalore.


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