Dugongs, popularly known as ‘Sea Cows,’ are the only surviving species of aquatic herbivores that belong to the order Sirenia of the Dugongidae family. Unfortunately, they are highly vulnerable to extinction and one among the critically endangered species of the International Union for Conservation of Nature (IUCN). They are positioned on the IUCN’s Red List of threatened species and are hunted to extinction for their precious meat and oil. But why are we discussing dugongs now? That is because these benthic seagrass creatures are officially declared functionally extinct on the Chinese coastline after a recent study in August 2022.
The dugong population in China has been reducing rapidly since the 1970s, primarily due to human-caused problems that led to habitat loss of the species. Besides, the study highlights some major reasons for dugong extinction in the region: overfishing and ship strikes. To understand the dugong population in the region, about 800 fishermen reportedly scattered across the South China Sea were interviewed. Of which only three respondents answered they had sighted dugongs over the last five years at the site. Another substantial piece of evidence that proves dugong’s extinction is the absence of any official field observation record of dugong sightings after 2000. The reason behind dugong extinction is that the area receives massive stress from the fishing industry for housing some of the rarest and the most spectacular marine biodiversity in the world. Hence, these marine species are hunted for their delicious meat. Another important reason for dugong extinction is bottom trawling, one of the most prominent fishing methods in today’s era. This destructive method uses a large net with a wide mouth and a small closure to catch a large quantity of fish. As bottom trawling is indiscriminate with its catches, it destroys the seabeds uprooting innumerable plants, thus, sweeping off natural habitats of dozens of aquatic animals in these nets.
Nevertheless, what does this mean to the remaining dugongs on India’s coastlines? India is a country known for its rich biodiversity. Since 1983, India has been a non-legal MoU signatory of the Convention on the Conservation of Migratory Species of Wild Animals (CMS) for various species such as Sea turtles, Dugongs, Raptors, and Siberian Cranes. According to the Wildlife Institution of India, there are about 200-250 dugongs in Indian waters, of which 75 are found in Andamans and 150 in the Palk Bay in the Gulf of Mannar. Therefore, in 2021, the Tamil Nadu government initiated the idea of establishing India’s first Dugong conservation reserve in the Gulf of Mannar in the Palk Strait Bay. Consequently, the state government allocated an area ranging around 500 sq. km in the Palk Bay and the Gulf of Mannar biosphere reserve to protect the fragile and stunning biodiversity of the region. In addition, the area houses some rare fishes, sea turtles, and seahorses. The reserve stretches from Adirampattinam in Thanjavur district to Amapattinam, a coastal neighbourhood in Pudukottai district.
But why are Dugongs significant to the marine ecosystem? Dugongs play a crucial role in balancing marine ecosystems. Since these vegetarian marine mammals feed on underwater seagrass, their repeated action promotes the regrowth of plant species. The availability of seagrass will also affect the existence of other sea creatures, such as dolphins, turtles, etc., which also depend on seagrass as a primary food source. Thus, the extinction of dugongs from Chinese waters is an alarming indication to speed up conservation efforts. India’s first dugong conservation reserve in the Gulf of Mannar is a stepping stone in the path of effectively planned conservation.
Chaitanya, K. S. V. (2021, September 4). India’s 1st dugong conservation reserve to be in Tamil Nadu. . . The New Indian Express. https://www.newindianexpress.com/states/tamil-nadu/2021/sep/04/indias-1st-dugong-conservation-reserve-to-be-in-tn-2354056.html
Shaji, K. A. (2022, January 16). India’s first dugong reserve will help protect the world’s only herbivorous marine mammal. Scroll.In. https://scroll.in/article/1014882/indias-first-dugong-reserve-will-help-protect-the-worlds-only-herbivorous-marine-mammal
Ives, M. (2022, August 27). The Dugong ‘Sea Cow’ Has Vanished from China’s Waters, Study Says. The New York Times. https://www.nytimes.com/2022/08/26/science/china-dugong-sea-cow-extinct.html