Maritime strategic planning cannot be done in isolation of marine eco-concerns. Marine species are known to perceive the environment around them through acoustic signals, and depend on sound for numerous functions like foraging, communication and navigation. Noise as a pollutant has found scant reference in the United Nations Environmental Programme (UNEP) document of 1982—the United Nations Convention on the Laws of the Seas (UNCLOS). The International Maritime Organization (IMO) is yet to include noise as a pollutant in its 1978 MARPOL Convention.

India’s location in the Indian Ocean Region (IOR) compels it to play a larger strategic role in the region. The growing energy needs of China—with the Gulf continuing to be its most preferred source—further causes the Chinese merchant fleet to transit the IOR. To ensure uninterrupted supply of energy resource, the Chinese have started to increase their presence in the region and this has, in turn, encouraged the Americans to also deploy their marine assets in the region.

The Indian Ocean Region (IOR) has profound strategic relevance not only for the nations in the region but also for other countries.1 The bulk of the world’s merchant fleets transit through one of the busiest sea lanes in the world, via the Malacca Straits. Also, the presence of major petroleum exports originating from the Gulf, encourage the major powers of the world to have a strategic presence in the IOR.

The end of the Cold War resulted in a fundamental swing from a navy designed to engage a blue water battle fleet to one focused on forward operations in littoral waters. The Cold War era had fuelled massive research and development (R&D) in design of sonars that was able to substantially minimize the uncertainties of the underwater environment. The shift of the naval theatre to the littoral waters led to a paradigm change in terms of technology requirements to retain the effectiveness of these sonars.