Gulf of Mannar Biosphere Reserve

Topic: Biodiversity and its Conservation · NCERT: Class 11, Ch 5 "Natural Vegetation"

Meaning

The Gulf of Mannar Biosphere Reserve (1989) is India's first marine biosphere reserve. It lies in the sea off Tamil Nadu, from Rameswaram to Kanyakumari, between India and Sri Lanka. It has 21 islands, coral reefs, seagrass beds and the dugong.

• It matters because it was the first reserve to apply the people-inclusive biosphere model to the sea, where fishing communities depend on the reef.
• It joined UNESCO's World Network of Biosphere Reserves (WNBR) in 2001, making it one of India's earliest sites on that list [2][3].

Explanation

What a biosphere reserve is, and why this one is marine

• Biosphere reserve: a large area of land, coast or sea, or a mix of these. It represents a typical ecosystem of its biogeographic region (a natural region with its own plants and animals) [2].
• Local human communities are treated as part of the system. People are not simply kept out [2].

• MoEFCC calls these reserves "sites for experimenting with and learning about sustainable development" [2].

• Most Indian reserves protect forests, mountains or deserts. Gulf of Mannar protects a shallow tropical sea, which is why it is called marine.

• Area: 10,500 sq km [2]. It is the second-largest biosphere reserve in India, after Kachchh (12,454 sq km) [2].

The marine ecosystem it protects

• Coral reefs: rock-like ridges built over many years by tiny sea animals called corals.
• Corals need warm, clear and shallow water with plenty of sunlight.

• The calm, shallow sea around the islands gives them these conditions.

• Seagrass beds: flowering plants that grow underwater on the sandy sea floor, like an underwater meadow.

• Dugong (also called the sea cow): a large, slow sea mammal that eats only seagrass.
• Cause → process → result: seagrass beds stay healthy → dugongs have food → the dugong survives here.

• If seagrass is lost through trawling or pollution, the dugong loses its food. So protecting seagrass also protects the dugong.

• 21 islands: small islands that lie along the coast and give the reef shelter.

How the three zones work here

Zone	What is allowed	Role in Gulf of Mannar
Core zone	Legally protected. No human interference	The islands and reefs where corals, seagrass and dugongs are left undisturbed
Buffer zone	Research, education and limited use that does no harm	Shields the core. Used as a field laboratory
Transition zone	Villages, fishing and sustainable use; outreach to local people	Coastal fishing villages from Rameswaram to Kanyakumari

• Why the zones work:
• Coastal people depend on the sea for fish and other resources → this puts pressure on the reef.
• The scheme gives people in the buffer and transition zones extra or alternative ways to earn a living → they need less from the core.

• Result: less biotic pressure (harm caused by people) on the core zone [2].

• Three objectives (NCERT Figure 5.9):

• Conservation: protecting genes, species and whole ecosystems in-situ (in their natural home) [2].
• Development: a better life for local communities without harming nature [2].
• Logistic support: research, monitoring, education and training [2].

Legal status, funding and management

• A biosphere reserve is not a protected-area category under the Wildlife (Protection) Act 1972. It is set up by an executive scheme of the central government [2].

• Only its core gets legal protection, through a national park or sanctuary placed inside it. Here the core is the Gulf of Mannar Marine National Park.

• Funding: a sub-scheme under the Centrally Sponsored Scheme "Conservation of Natural Resources and Ecosystems" (CNRE) of MoEFCC. The Centre and State share costs 60:40, since Tamil Nadu is not a North-Eastern or Himalayan state [2].

• Run by: the State Forest Department (here, Tamil Nadu) [2].

Where it occurs

• Location: Tamil Nadu coast, in the sea from Rameswaram to Kanyakumari, between India and Sri Lanka [2].

• The Gulf of Mannar lies south of Palk Bay. Adam's Bridge (Rama Setu), a chain of shoals (shallow sandbanks), separates the two.

• Within India's 18 biosphere reserves (91,425.11 sq km in total, December 2023) [2]:

• It is No. 4 in order of setting up, all in 1989 with Sunderban, Manas and Great Nicobar.
• It belongs to the southern group, with Nilgiri, Agasthyamalai and Seshachalam.

• It is one of three coastal and marine reserves: Gulf of Mannar (marine), Sunderban (delta mangroves) and Great Nicobar (island).

• On UNESCO's world network: added in 2001, in the same year as Sunderban [2][3].

• Order of joining: Nilgiri (2000) → Gulf of Mannar and Sunderban (2001) → Nanda Devi (2004) → … → Cold Desert (2025, India's 13th) [2][3].

• Global programme: UNESCO's Man and the Biosphere (MAB) Programme, started in 1971 [2]. The world network has 785 sites in 142 countries (2025) [3].

Don't confuse with

• Nilgiri Biosphere Reserve: India's first biosphere reserve overall (1986) and the first Indian site on the WNBR (2000) [2]. Gulf of Mannar is the first marine reserve (1989).
• Sunderban Biosphere Reserve: also 1989 and also on the WNBR in 2001. But it is a delta mangrove reserve in West Bengal, not a marine coral-reef reserve. It is also smaller (9,630 sq km) than Gulf of Mannar (10,500 sq km) [2].
• Gulf of Mannar Marine National Park: a legal protected area under the Wildlife (Protection) Act 1972 that forms the core. The biosphere reserve is the larger area around it, and it has no legal status of its own.
• Palk Bay / Palk Strait: the sea north of Adam's Bridge. The Gulf of Mannar is the sea south of it.

Prelims Hooks

• First marine biosphere reserve of India: Gulf of Mannar, Tamil Nadu (1989). It has 21 islands, coral reefs, seagrass and dugongs.
• Size order: Kachchh (12,454) > Gulf of Mannar (10,500) > Sunderban (9,630) > Cold Desert (7,770) sq km [2].
• Extent: from Rameswaram to Kanyakumari, between India and Sri Lanka [2].
• WNBR year: 2001, together with Sunderban. Nilgiri was the first, in 2000 [2][3].
• Flagship animal: the dugong (sea cow), which grazes on seagrass. Do not pair it with Sunderban, which is known for the Bengal tiger.
• Trap: a biosphere reserve is not a protected area under the Wildlife (Protection) Act 1972. It is a central scheme (CNRE sub-scheme), and UNESCO's MAB International Coordinating Council decides which sites join the world network [2].

Mains Points

• People-inclusive marine conservation (GS-III):
• The coastal communities from Rameswaram to Kanyakumari depend on the sea.
• Under the core–buffer–transition model, they get other ways to earn a living in the outer zones. This lowers pressure on the reefs and seagrass in the core [2].

• This differs from the "fortress" model of national parks, which keeps people out.

• Gaps in protection:

• The reserve has no legal status of its own. Only its core is protected, through the marine national park.

• Corals and seagrass are fragile. Overfishing and harm to seagrass threaten the dugong's food supply. So the reserve needs strong monitoring and research, which is its logistic support role [2].

• Link to global commitments: marine biosphere reserves support in-situ conservation under the CBD (1992) and the area-based targets of the Kunming-Montreal GBF (2022). India's 13 WNBR sites, Gulf of Mannar among them, contribute to a network of 785 sites in 142 countries [2][3].

Related concepts

• Biosphere reserve
• Man and Biosphere Programme
• Nilgiri Biosphere Reserve
• Nanda Devi Biosphere Reserve
• Nokrek Biosphere Reserve
• Manas Biosphere Reserve
• Sunderban Biosphere Reserve
• Great Nicobar Biosphere Reserve
• Similipal Biosphere Reserve
• Dibru-Saikhowa Biosphere Reserve

Read more

• Biosphere reserves and UNESCO's Man and the Biosphere Programme