Climate Change Effects: An Ocean at risk

Climate Change Effects: An Ocean at Risk

By: Nisha D’Souza and N M Ishwar
Climate change and anthropogenic factors, are causing many marine species to die out, resulting in a devastating impact on coastal populace. Replenishing mangrove ecosystems can provide a viable solution to tackle this problem.
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Climate Change Effects: An Ocean at Risk

With over 7 per cent of recorded species globally, including 45,000 plants, and 91,000 animals, India embodies the definition of mega-diverse country. India’s vertebrate groups demonstrate high levels of endemism with the 10th highest global levels of endemism among birds (69 species), 5th in reptiles (156 species), and 7th in amphibians (110 species) (MoEF, 2014). This is unsurprising; India by virtue of its geomorphologic and climatic variability hosts a wide variety of ecosystems, including 4 of 34 globally identified hotspots: The Himalayas; the Western Ghats; the North-East; and the Nicobar Islands (ibid).

India’s biodiversity underpins ecosystem functions and services that are invaluable to humanity, and which form the support system for growth and development of the country. For instance, India is the third largest producer of fish in the world, contributing almost 5 per cent to global fish production; the annual fish catch from India is valued at over INR 190 billion (ibid).

The pharmaceutical and medicinal attributes of more than 3,800 species of plants in India have been officially documented, and marketed, making the country one of the largest producers of medicinal herbs globally (ibid).

Forests are estimated to contribute more than 1.5 per cent to the country’s GDP; with a geographical area of more than 20 per cent of the country (ibid), they provide multiple benefits that are not yet reflected in national accounts.

Despite this dependency, the pressures and threats facing biodiversity are increasing. More than 1039 species occurring in India are categorised as threatened under the International Union for Conservation of Nature (IUCN) Red List of Threatened Species; 123 of these species are endemic. There are hundreds more Indian species that have not yet been assessed. Amongst the most vulnerable and least understood species and habitats are the coastal and marine (IUCN, 2015). From whales to plankton, human actions are impacting ocean species and ecosystems. Sea grass beds, coral reefs, mangroves and other tropical marine environments are critical habitats that support the highest concentrations of marine biodiversity in the world. They provide feeding, nursery and spawning grounds for a wide variety of marine life and protect the coastline from severe storms and sea level rises. India has an estimated 153,000 square km of coastal wetlands and hosts an incredible array of diversity including 25 marine mammals, 5 species of marine turtles, 2,182 fishes, 844 marine algae and 39 mangrove species (MoEF, 2014).

The 21st century marks a time of rapid and unprecedented ocean biodiversity loss. Ninety per cent of fish species have been extracted from the oceans including large sharks, groupers, snappers, wild salmon and many reef fish including parrotfish and humphead wrasse. India is the world’s second largest fish producing country; an estimated 3.4 million tonnes of marine fish were landed in 2015 (CMFRI, 2016). But habitat destruction, overfishing, unsustainable coastal development and ocean warming are driving species decline across the coast. Ocean pollution is also increasingly becoming an issue; with recent reports suggesting that over 30 per cent of globally consumed seafood contains plastic particles (ibid).

In response to these pressures, several marine species are on the move. Mangroves are invading marsh dominated ecosystems along the east coast of India, representing one of the most dramatic plant range shifts occurring globally today. Small pelagic fish like oil sardines and mackerels, the mainstay of many South Indian fisheries, are now found beyond Gujarat and West Bengal. But not all species are able to cope with the threats. In Lakshadweep corals are displaying signs of extreme heat stress; in some areas dying reefs are already being invaded by opportunistic turf algae. It is estimated that the rate of habitat change in the oceans is between 1.5 and 5 times faster than on land (Laffoley, 2016).

The majority of marine species identified by the Government of India for priority conservation fall within the endangered categories of the IUCN Red List of Threatened Species including whales sharks, all five species of marine turtle (Green, Olive Ridley, Leatherback, Hawksbill and Loggerhead) and dugongs. All these species are characterised by declining populations in Indian waters.

The coastline supports more than 30 per cent of the Indian population who are dependent on its rich and exploitable resources. Changes in ocean biodiversity will greatly influence fisheries production, as well as livelihood and food security for the coastal populations. In 2014, sardine landings in the Gulf of Mannar and Palk Bay brought in revenue between INR 1.3 and 1.4 billion; fish migrations will affect hundreds of fisher families across the coastline.

In the midst of dismaying news there are plenty of reasons for optimism and hope. Conservation efforts to protect and restore marine and coastal ecosystems have received increased attention and funding. For the first time it is possible to measure, document and communicate the powerful impacts humans are having on the oceans. We can map the boundaries of our life support systems and understand why protecting nature is neither a luxury nor even an option—it is critical to our survival.

At the recent IUCN World Conservation Congress in September 2016, leaders discussed that ocean restoration requires expanding protection to at least 30 per cent within national jurisdictions. Globally, over 2.5 million sq km of area safeguarded for fish and other wildlife. India contributes by protection of more than 6 per cent of our coastal waters. Through the Sustainable Development Goals, India is committed to conserving at least 10 per cent of coastal and marine areas by 2020, and sustainably managing, protecting and restoring them to achieve healthy and productive oceans. IUCN is continuing to work with the Indian government to build marine and coastal biodiversity and community resilience through the Mangroves for the Future initiative.


Central Marine Fisheries Research Institute. October, 2016. Estimated Marine Fish Landings in India During 2015. Available at:

IUCN. 2016. See grass for it’s Worth: Valuation of Seagrass for Community-Support Conservation in Palk Bay, India, pp. 30.

Laffoley, D. and Baxter, J. M. 2016. Explaining Ocean Warming: Causes, Scale, Effects and Consequences. 456 pp.

Ministry of Environment, Forest and Climate Change. 2014. India’s Fifth National Report to the Convention on Biological Diversity. pp. 36.

The IUCN Red List of Threatened Species, Available at:

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