Waving meadows of emerald grasses half as a portly form drifts by the shallow waters. Like a blimp led astray, the creature makes use of its entrance flippers to paddle gently because it nibbles on the seagrass that makes its residence. Silt stirs from the shallow seafloor, coral reefs reveal themselves in a riot of colors, with shoals of fish scurrying out of the manner, and a whole ecosystem comes into view.
Meet the dugong — the farmer of the sea.
May 28 is well known yearly as World Dugong Day. Dugongs (Dugong dugon) are the solely herbivorous mammals present in India’s marine ecosystems. This light large — referred to as the sea cow however resembling a cross between a seal and a whale — is distributed by the Indo-Pacific area. Due to their dependence on seagrass beds for habitat and meals, dugongs are restricted to shallow waters, the place they spend the day feeding on seagrasses of the genera Cymodocea, Halophila, Thalassia, and Halodule. They root at the base of shorter seagrass species, consuming rhizomes, stems, and leaves, thus clouding the shallow waters. This is how they earned their epitaph. (Also see the addendum.)
Seagrass is low in vitamins, so dugongs feed extensively all through the day to satisfy their each day necessities. They can devour 20-30 tonnes of seagrass per day, crushing leaves and stems in opposition to their horned enamel earlier than swallowing. Unlike different marine mammals, the manner they eat permits dugongs to digest cellulose, though the course of wears down their enamel shortly. For this purpose, dugongs quickly regrow enamel in a number of iterations all through their lives.
Unlike manatees, their shut relations, dugongs are extra strictly marine, preferring waters a few metres deep. They are discovered alongside the Indian shoreline, primarily inhabiting heat waters round the Andaman and Nicobar Islands, the Gulf of Mannar, Palk Bay, and the Gulf of Kutch. The dugong is a long-lived species, capable of stay as much as 70 years.
Dugongs are additionally usually solitary or present in small mother-calf pairs. Researchers have often noticed small teams, however giant herds — as are widespread in Australian waters — are uncommon in India.
Individuals attain reproductive maturity after solely 9 or ten years and can provide delivery at intervals of round three to 5 years. Due to its sluggish reproductive cycle, prolonged time to maturity, and rare calving, a dugong inhabitants’s most potential development price is estimated to be nearly 5% per yr.
Threatened waters
But for his or her unassuming nature, dugongs are listed as being ‘vulnerable’ on the IUCN Red List for Threatened Species. The threats they face worldwide embody quickly declining populations and the ongoing degradation of their seagrass habitats. In India, they’re categorized as ‘regionally endangered’. Once widespread in Indian waters, their numbers have dwindled to an estimated 200 people, with each their inhabitants measurement and geographic vary persevering with to say no.
According to analysis by unbiased marine researcher Prachi Hatkar, coastal areas round India are more and more below strain from increasing residential, leisure, and agricultural actions. As extra folks stake declare to those areas, the danger of air pollution rises. Pollution may have an effect on them instantly, with research exhibiting the accumulation of mercury and organochlorine compounds of their muscle tissues.
Because dugongs reproduce slowly and require huge, undisturbed seagrass meadows to thrive, their populations are extremely weak to human disturbances. Seagrass meadows, their main habitats, are being misplaced at an alarming price. Primary threats stem from altering fishing strategies, which threaten the meadows. Fishers as soon as relied on non-mechanised boats to fish in shallow waters, together with seagrass habitats. But with the introduction of trendy fishing applied sciences, these conventional boats have steadily given option to mechanised ones.
The development of ports, dredging, and land reclamation for industries and tourism have additionally wreaked havoc on these delicate ecosystems, and air pollution from agricultural runoff, sewage, and industrial effluents have degraded water high quality, affecting seagrass well being.
The ever-present risk of local weather change, perceptible in rising sea temperatures, ocean acidification, and excessive climate occasions like cyclones, additionally impacts seagrass ecosystems, lowering the availability of meals in addition to secure breeding habitats for dugongs.
Another main risk to dugong populations in Indian waters is unintended entanglement in fishing gear, particularly gillnets and trawl nets. Dugongs are air-breathing mammals that must floor often. But as soon as entangled, they usually drown earlier than fishers can launch them. Many of these deaths go unreported, additional complicating conservation efforts.
Increased human motion and exercise in dugong habitats and extra boat visitors in the Gulf of Mannar, Palk Bay, and the Gulf of Kachchh — all instantly threaten the species. Dugongs additionally usually relaxation close to the floor, making them weak to collisions with fast-moving boats, resulting in accidents or fatalities.
Yet one other risk is unlawful searching. While dugongs are a Schedule I species in India, having fun with the highest degree of safety granted by legislation, poaching nonetheless happens, particularly in the distant areas of the Andaman and Nicobar Islands.
Way to the future
Unlike manatees, dugongs are shy creatures, preferring to keep away from interacting with people when potential. This creates a common lack of consciousness about the species, even amongst coastal and fishing communities, in addition to much less consideration from the bigger conservation group. India has been celebration to the Convention on the Conservation of Migratory Species of Wild Animals since 1983 and has additionally been a signatory to the Convention’s Memorandum of Understanding on Dugong Conservation and Habitat Management throughout their vary since 2008.
In 2022, the Government of India formally introduced the creation of the nation’s first dugong conservation reserve, spanning 448.3 sq. km in the coastal waters of Palk Bay, Tamil Nadu. Recent research have indicated that this bay is the final stronghold for these light herbivores in Indian waters, and the proposed reserve space has round 122.5 sq. km of intact seagrass beds, making certain habitat and meals for the dugong inhabitants.
This transfer, to guard the species at a nationwide degree, stems from long-term monitoring and analysis by the OMCAR Foundation (an NGO), the Wildlife Institute of India, and the Tamil Nadu Forest Department: they’ve been working to enhance dugong conservation and seagrass restoration for greater than a decade. Their efforts can go a great distance in making certain the survival of dugongs and their delicate lives.
“Dugongs are gentle giants and act as gardeners of the sea, quietly shaping our oceans by nurturing seagrass meadows,” Ms. Hatkar mentioned. “But their survival now depends on ours — on how urgently we act to protect their fading habitats from pollution, coastal development, and neglect.”
Helping dugong conservation
An necessary step folks can take is to guard and restore seagrass habitats. To achieve this, we want rigorous mapping and monitoring of present seagrass meadows to establish extra priority conservation areas, very similar to the Gulf of Mannar Biosphere Reserve. Activities that injury seagrass must be restricted and community-led seagrass stewardship, together with involving native fishers to observe and restore seagrass, can go a great distance in sustaining the dugongs’ habitat. Regulating dangerous fishing practices, akin to banning gill nets and backside trawling, in identified dugong habitats may also assist forestall unintended entanglement.
We additionally want to advertise non-destructive, sustainable fishing strategies that fisherfolk have utilized in the previous. Alternative livelihood choices akin to dugong-friendly ecotourism utilizing native youth as eco-guides can fulfil the twin position of monitoring dugong populations whereas elevating consciousness of their habitats and behavior, all whereas empowering native communities.
Increasing consciousness and group involvement have all the time been necessary facets of dugong conservation. Many conservation practitioners are conducting consciousness campaigns in coastal villages about the ecological significance of dugongs, and lots of native communities and fishers are skilled to report dugong sightings or strandings, facilitating rescue operations when wanted.
Another necessary side is strengthening analysis. Researchers want extra assist, each monetary and institutional, for long-term research of dugong populations, behaviours, genetics, and threats. Developing citizen science programmes and utilizing the conventional ecological information of native communities will add one other dimension to present analysis. Additionally, advances in tagging and drone expertise may be mobilised to trace dugong actions and establish crucial habitats.
Addendum: why seagrass issues
Seagrass is an underwater flowering plant, to not be confused with seaweed. Classified as wetland ecosystems, seagrass meadows stabilise the seafloor, assist fisheries, seize carbon, and shelter marine life. Healthy seagrass is important for dugongs and marine life akin to turtles and fish. A 2022 research by the National Centre for Sustainable Coastal Management documented 516.59 sq. km of seagrass habitat in India. This interprets to a carbon dioxide sequestration potential of as much as 434.9 tonnes per sq. km annually.
India’s most in depth seagrass meadows happen alongside the Gulf of Mannar and Palk Bay, off the coast of Tamil Nadu, and collectively assist greater than 13 species of seagrass — the highest range in the Indian Ocean. The Andaman and Nicobar Islands additionally assist wealthy seagrass beds and related biodiversity. While seagrass is current in the shallow reefs of the Lakshadweep Islands and alongside the coast of Kachchh, they’re patchy regardless of being ecologically important. In Kachchh particularly, port actions and air pollution threaten these coastal wetlands.
The coast of Andhra Pradesh and Odisha additionally helps minor seagrass beds alongside estuaries, however these habitats aren’t in depth or appropriate for dugong populations immediately.
Priya Ranganathan is a doctoral pupil and researcher at the Ashoka Trust for Research in Ecology and the Environment (ATREE), Bengaluru.
Published – May 28, 2025 05:30 am IST
