The marine environment, oceans, seas and adjacent coastal areas, with their opportunities for sustainable development form an essential component of the global life support system. The United Nations Convention on the Law of the Sea (UNCLOS) sets forth rights and obligations of the States and provides the international basis to pursue the protection and sustainable development of the marine and coastal environment and its resources (Agenda 21, Chapter 17 of the United Nations Conference on Environment and Development, 1992).
Geomorphologic and climatic factors along with the nutrients supplied by the coastal rivers make the Indian peninsula exceptionally productive and biologically rich. It supports mangroves, coral reefs, sea grass beds and vast areas of biodiversity. However, high risks of ecological deterioration through commercialisation and over capitalisation of the fishing sector exist as demands for marine products in both domestic and export markets grow. It is therefore, important to judiciously manage and integrate marine fisheries into coastal zone management for sustainable yields and protection of the vulnerable areas and species.
Marine living resources of India
India has a long coastline of 8,118 km inhabited by about 225 million people and an Exclusive Economic Zone (EEZ) extending to 2.02 million sq km. The coastal zone supports large marine resources and contains the highest biological diversity as compared to any other part of the sea (Table 1).
In the marine capture fisheries sector, the annual potential yield is assessed to be around 3.934 million tonnes (Ministry of Agriculture, 2000). Of this, 58 per cent of the potential lies within the 50 m depth zone, 35 per cent in the 50-200 m zone and the remaining 7 per cent beyond the 200 m zone. About 75 per cent of the total estimated marine fishery potential is presently being tapped with hardly 25 per cent left for future exploitation. While the resources within the 0-50 m depth are almost exploited to the maximum sustainable yield levels, the resources available beyond 50 m depth still offer scope for sustainable exploitation.
Threats to living marine resources
There are several areas of concern, amongst which a few major ones include: unsustainable exploitation of the coastal marine living resources through illegal, unregulated and unreported destructive and unsustainable fishing practices; land based sources of pollution due to disposal of untreated domestic, industrial and agricultural wastes etc., sea based sources of pollution including oil spill, introduction of alien species through ballast water discharges, ocean debris etc.; and degradation of the critical coastal habitats such as mangroves, coral reef beds, wetland/lagoonal ecosystems, turtle nesting grounds and areas leading to loss of biodiversity.
Physical alteration, including modification of critical coastal habitats has led to severe accretion of beach sand on the mouth of estuaries. Degraded coral reefs, mangroves and overexploited coastal areas have disturbed the delicate balance between marine life and coastal habitats. As a result nearly 8 species of marine mammals, 5 species of marine turtles, 1 species of hemichordate, 3 species of cephalochordate, 6 species of echinoderms, 2 species of Xiphosurans, 15 species of molluscs, 10 species of crab and 1 species each of Echiuroid and Brachipod are endangered (Ministry of Environment and Forests, 2000). Out of 52 species of marine fish in the mangrove areas of the country, 9 are vulnerable and 2 are endangered while out of 41 invertebrates, 4 are vulnerable and 1 species is critically endangered (Ministry of External Affairs, 1997).
Marine Protected Areas
In 2004, the Seventh Meeting of the Conference of Parties (COP7) to the Convention on Biological Diversity (CBD) agreed that marine (and coastal) protected areas (MPAs), as part of a wider marine and coastal management framework are one of the essential tools for the conservation and sustainable use of marine and coastal biodiversity and resources. Aquatic biodiversity protection and conservation includes: protection of habitat and endangered species; cultural ecological/social protection; multi use and conflict management; sustainable extractive use of the resources and biodiversity; enhancement of economic well being; improvement in quality of life and implementation of the ‘ecosystem approach’; and the ‘precautionary approach’ to resource conservation and management (International Collective in Support of Fishworkers, 2008).
There are 33 MPAs in India, but despite available policy spaces for participatory management of MPAs, various legal and institutional issues hamper implementation of livelihood sensitive approaches. The very effectiveness of the MPA initiative gets affected as communities do not consider themselves a part of the MPA process. This calls for an effective conservation and management regime for the entire Indian EEZ to be developed through participatory and integrated processes. It will involve collaboration and coordination between Central ministries and the concerned State departments, research institutions and non government organisations so that the preferential access rights of fishing communities can be secured and are in sync with the international conventions and codes.
Climate change and its impact
Global climate change affects a broad range of marine species and ecosystems particularly during the warmest years, pointing to gradual alteration of marine ecosystems (Food and Agriculture Organisation (FAO), 2009). In general, there is a tendency for the warmer water species to experience changes in habitat size and productivity due to changes in the marine food webs. Increased risks of species invasions and the spread of vector-borne diseases are the other concerns (FAO, 2009).
Globally, climate change is increasingly emerging as a serious threat to reefs and they are likely to face destruction within the next 50 years if predictions about climate change become a reality. Coral bleaching (loss of symbiotic algae from the polyp) in response to periodic elevated sea surface temperature (or other types of stress) is a possibility. Corals generally survive in a narrow range of water temperature, from 26°C to 28°C and are intolerant of temperatures just a few degrees warmer than usual. Corals provide food and habitat to marine organisms. Their damage can have a direct impact on the intricate web of marine life with negative implications for fish population. As reefs become degraded, corals die and become overgrown by algae; corallivorous fish are replaced by fish that are algal grazers. With further degeneration, reef dwelling fish may disappear entirely to be replaced by pelagic species. Ultimately, marine biodiversity in terms of corals, fish, shellfish and other reef inhabitants may plummet.
As per the Central Marine Fisheries Research Institute, Kochi, the responses to climate change by different marine species are: changes in growth, senescence and species composition of phytoplankton at higher temperature; extension of distributional boundary of small pelagics – oil sardine and Indian mackerel, towards the northern latitudes; extension of depth of occurrence – Indian mackerel descending to deeper depths due to warming of sea surface; shift in the spawning season of fish; change in the migratory pattern of certain species; and phonological changes.
Such changes are likely to lead to novel mixes of organisms in a region, leaving species to adjust to new prey, predators, parasites, diseases and competitors. In addition, the species inhabiting coral atolls and ice dominated coasts may become particularly vulnerable to sea level rise and the associated risks of flooding, saline intrusion and coastal erosion. These changes may impact the type and value of fisheries (Table 2).
Contrary to the general perception of only negative impacts, climate change may trigger a move towards sustainability through good governance, management principles and approaches in the wake of resilience and adaptive capacities of aquatic resource ecosystems, fisheries, aquaculture and of aquatic resource dependent communities.
The impact of climate change on marine living resources is inadequately understood. The key to minimal impact with maximum opportunities is to follow creative adaptive strategies vis-à-vis existing policy, legal and management frameworks that require multi dimensional understanding of the impacts of climate change (FAO, 2009). In addition, information gaps and capacity building requirements need to be identified and addressed through a network of research, training and academic agencies. Existing management plans for the fisheries, coastal zones and watersheds need to be reviewed and developed further to ensure that they cover potential climate change impacts, mitigations and adaptation responses. Connections to wider planning and strategic processes also need to be identified and adjusted.
India requires integrative new approaches at the national, state and local levels for: management and sustainable development of coastal areas including EEZ; marine environmental protection; sustainable use and conservation of marine living resources of the high seas; management of critical uncertainties of the marine environment and climate change; strengthening of international and regional cooperation and coordination; and sustainable development of small islands.
Oceans, seas, islands and coastal areas are critical components of the earth’s ecosystem for global food security in general and for sustaining economic prosperity and the well being of developing countries in particular.