A new report launched at the International Union for Conservation of Nature (IUCN) Conservation Congress, in Abu Dhabi, United Arab Emirates, last month, highlighted the growing threat to the dugong population in India.
In the South Asian region, dugongs, also known as sea cows, are primarily found in the Gulf of Kutch, the Gulf of Mannar–Palk Bay region (located between India and Sri Lanka), and the Andaman and Nicobar Islands. The report, ‘A global assessment of dugong status and conservation needs’, said that the marine mammal’s long-term survival in the Gulf of Kutch and the Andaman and Nicobar Islands was “highly uncertain” and “challenging” respectively. Meanwhile, in the Gulf of Mannar-Palk Bay, its population appears to be “much lower” than in the recent past.
Currently, the IUCN, which compiles the official Red List of endangered species, lists sea cows as a species vulnerable to extinction. In India, they are listed under Schedule I of the Wild Life (Protection) Act, 1972, which grants the species the highest legal protection against hunting and trade.
Here is a look at what dugongs are, why they are significant for the marine ecosystem, what kind of threats they face, and how the government is trying to conserve them.
What are dugongs?
Dugongs (Dugong dugon) are a marine mammal, which are believed to have inspired ancient seafaring tales of mermaids due to their gentle — seemingly benign — disposition. They are related to manatees, with whom they share a plump appearance, but also have a dolphin fluke-like tail. An adult dugong typically grows up to 10 feet and weighs around 420 kilograms.
The mammals are exclusively herbivorous, and seagrass meadows are their main source of food — the reason why they are also called sea cows.
Anant Pande, head of the Oceans and Coasts Conservation Division of the WWF-India, told The Indian Express over email, “Dugongs inhabit shallow, warm coastal waters, often seen grazing in calm sheltered bays, lagoons, and estuaries less than 10 meters deep…An individual dugong requires about 30-40 kg of seagrass to feed upon every day.”
Why are they significant?
Dugongs play a crucial role in maintaining healthy seagrass ecosystems. For instance, when they graze seagrass, the leaves are pruned and old shoots are uprooted. “This natural mowing process keeps meadows healthy, prevents overgrowth, and stimulates carbon storage in the sediment below… Dugongs not only maintain the productivity of seagrass ecosystems but also contribute to climate regulation by sustaining one of the most efficient carbon sinks on the planet,” Pande said.
Also, while feeding on seagrass, dugongs help release nutrients from the sediment, which are consumed by other marine species, especially commercially important fish, shellfish, and numerous invertebrates such as sea cucumbers.
K Sivakumar, professor at Pondicherry University’s Department of Ecology and Environmental Sciences, told The Indian Express over email that seagrass habitats where dugongs were present provided “a minimum of Rs 2 crore per year worth of additional fish production”. He said, “Fish production was significantly low in the seagrass beds where dugongs are not found.”
Why is the dugong population in India under threat?
Once abundant in Indian waters, the dugong population has drastically reduced over the years. A 2012 report by the Ministry of Environment, Forest and Climate Change (then known as the Ministry of Environment and Forests) said that there were about 200 sea cows in the country. This number does not seem to have substantially increased. While Sivakumar says that currently, there are between 400 and 450 individuals in the region, others suggest that the number is less than 250.
Pande said, “The largest and most stable group inhabits the Palk Bay-Gulf of Mannar seascape along Tamil Nadu’s coastline, where around 150 to 200 dugongs are believed to persist. Smaller, more fragmented populations survive in the Andaman and Nicobar Islands (less than 50 individuals), and a handful of individuals continue to be sighted in the Gulf of Kutch in Gujarat (less than 20 individuals).”
Note that it is difficult to ascertain the exact number of sea cows in India as they are elusive and live in cloudy and murky coastal waters, where traditional methods of survey often fail.
Human activities and degradation of coastal habitats are the primary drivers of decline in the dugong population currently. For instance, a majority of sea cows die due to accidental entanglement in fish nets.
Sivakumar said, “High turbidity, pollution and fishing are the threats to dugongs in the Gulf of Kutch. Fisheries bycatch and pollution are the major threats in Tamil Nadu. In the Andamans, fisheries-related mortality is higher.”
A recent study, ‘Toxic traces: First insights into metals and metalloids in dugongs (Dugong dugon) from India’, published in the journal Marine Pollution Bulletin, found five toxic elements — arsenic, cadmium, chromium, mercury, and lead — in tissues of various organs from 46 stranded dugongs in India. The analysis was conducted by Sivakumar, Pande, and Sweta Iyer, Chinmaya Ghanekar and Jeyaraj Antony Johnson — all three based at the Wildlife Institute of India, Dehradun.
Pande said, “This was the first global assessment of trace metal and metalloid concentrations in these vital organs (like liver and kidneys, and muscles) of dugongs. These metals enter the sea through industrial discharge, agricultural runoff, and untreated wastewater, eventually settling into the sediments where seagrasses grow.”
Another issue is that the reproductive rate of sea cows is quite slow. A female dugong gives birth once in several years, which makes the species more vulnerable to extinction.
How has the government been trying to conserve dugongs?
Over the years, the Centre and state governments have taken several steps to help conserve the dugong population in the country. For instance, the MoEFCC in 2010 constituted a ‘Task Force for Conservation of Dugongs’ to examine the issues related to the conservation of sea cows.
Subsequently, a national dugong recovery programme was launched in partnership with the governments of Tamil Nadu, Gujarat and the Andaman and Nicobar Islands. Under this programme, the Dugong Conservation Reserve was established in Palk Bay by the Tamil Nadu government in 2022. The 448-square-kilometre reserve aims to protect seagrass meadows and the dugongs that depend on them.
However, researchers suggest that authorities need to do more to ensure the rise in the dugong population.
“While these actions have certainly tilted the needle in favour of dugongs, enforcement of regulations in protected dugong habitats, reduction of threats, especially bycatch in fisheries and monitoring need to be strengthened. Fishing-related deaths of dugongs have reduced but still continue, largely due to the lack of affordable alternatives to harmful gear and lack of an incentive-based model to reduce fishing pressure on dugong habitats,” Pande said.
The views of Pande and Sivakumar are personal.
A dungong near the Andaman and Nicobar Islands. (Photo: Wikimedia Commons) 
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