Gulf of Mannar
Encyclopedia
The Gulf of Mannar is a large shallow bay forming part of the Laccadive Sea
in the Indian Ocean
. It lies between the southeastern tip of India
and the west coast of Sri Lanka
. A chain of low islands and reefs known as Adam's Bridge, also called Ramsethu, which includes Mannar Island
, separates the Gulf of Mannar from Palk Bay, which lies to the north between India and Sri Lanka. The Thamirabarani River
of south India and the Aruvi Aru of Sri Lanka drain into the Gulf.
species have been recorded in the Gulf of Mannar. Sea turtle
s are frequent visitors to the gulf as are sacred shark
s, dugong
s, and dolphin
s. However, the combined effects of 47 villages, with a total population of around 50,000 has meant that overharvesting of marine species has become a problem. Fish catches have declined, as have pearl oyster
, gorgonian coral, and acorn worm
populations. Local fishermen rely on the reef to feed their families, but destructive fishing methods combined with the stress of pollution and coral mining have meant both nearshore and offshore catches have decreased. Endangered species include dolphins, dugongs, whale
s and sea cucumbers.
and Dhanushkodi were declared the Gulf of Mannar Marine National Park
. The park and its 10 km buffer zone were declared a Biosphere Reserve
in 1989.
The Gulf of Mannar Biosphere Reserve covers an area of 10,500 km² of ocean, islands and the adjoining coastline. The islets and coastal buffer zone includes beach
es, estuaries, and tropical dry broadleaf forests
, while the marine environments include seaweed
communities, sea grass communities, coral reef
s, salt marsh
es and mangrove
forests.
The Gulf of Mannar is known for its pearl banks of Pinctada radiata and Pinctada fucata for at least two thousand years. Pliny the Elder
(23–79) praised the pearl fishery of the gulf as most productive in the world. Although extraction of natural pearls is considered too expensive in most parts of the world, it is still conducted in the gulf.
The chief seaports on the Gulf of Mannar are Thoothukudi
(Tuticorin) in Tamil Nadu, and Colombo
in Sri Lanka. While these ports can accommodate deep-draft vessels, the shallow Palk Strait can only accommodate small shallow-draft vessels. In July 2005, the Indian Government took preliminary steps to go ahead with the Sethusamudram Shipping Canal Project
, which would create a deep channel linking the Gulf of Mannar to the Bay of Bengal
. Project boosters emphasize the benefits of a direct shipping route that connects India's east and west coasts without the long trip around Sri Lanka; environmentalists have warned against the grave damage such a project could cause to the sea life and fisheries of the Palk Strait and the Gulf.
Laccadive Sea
The Laccadive Sea or Lakshadweep Sea is a body of water bordering India , the Maldives, and Sri Lanka. It is located to the west of Kerala...
in the Indian Ocean
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
. It lies between the southeastern tip of India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
and the west coast of Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
. A chain of low islands and reefs known as Adam's Bridge, also called Ramsethu, which includes Mannar Island
Mannar Island
Mannar Island, formerly called Manar Island, is part of Mannar District, Sri Lanka. It is linked to the rest of Sri Lanka by a causeway.It has an area of about 50 square kilometres, mainly covered with vegetation and sand.Rama's Bridge or Rama Setu ,[1] is a chain of limestone shoals, between...
, separates the Gulf of Mannar from Palk Bay, which lies to the north between India and Sri Lanka. The Thamirabarani River
Thamirabarani River
The Thamirabarani River originates from the famous Agastyarkoodam peak in the hills of the Western Ghats above Papanasam in the Ambasamudram taluk and flows through Tirunelveli & Tuticorin districts of the Tamil Nadu state of southern India...
of south India and the Aruvi Aru of Sri Lanka drain into the Gulf.
Marine sanctuary
Located on the southeastern tip of the subcontinent, the Gulf of Mannar is known to harbour over 3,600 species of flora and fauna, making it one of the richest coastal regions in Asia. 117 hard coralCoral
Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...
species have been recorded in the Gulf of Mannar. Sea turtle
Sea turtle
Sea turtles are marine reptiles that inhabit all of the world's oceans except the Arctic.-Distribution:...
s are frequent visitors to the gulf as are sacred shark
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....
s, dugong
Dugong
The dugong is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's sea cow , was hunted to extinction in the 18th century...
s, and dolphin
Dolphin
Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in 17 genera. They vary in size from and , up to and . They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating...
s. However, the combined effects of 47 villages, with a total population of around 50,000 has meant that overharvesting of marine species has become a problem. Fish catches have declined, as have pearl oyster
Oyster
The word oyster is used as a common name for a number of distinct groups of bivalve molluscs which live in marine or brackish habitats. The valves are highly calcified....
, gorgonian coral, and acorn worm
Acorn worm
The Acorn worms or Enteropneusta are a hemichordate class of invertebrates, closely related to the echinoderms. There are about 90 species of acorn worm in the world, the main species for research being Saccoglossus kowaleskii....
populations. Local fishermen rely on the reef to feed their families, but destructive fishing methods combined with the stress of pollution and coral mining have meant both nearshore and offshore catches have decreased. Endangered species include dolphins, dugongs, whale
Whale
Whale is the common name for various marine mammals of the order Cetacea. The term whale sometimes refers to all cetaceans, but more often it excludes dolphins and porpoises, which belong to suborder Odontoceti . This suborder also includes the sperm whale, killer whale, pilot whale, and beluga...
s and sea cucumbers.
Conservation
In 1986, a group of 21 islets lying off the Tamil Nadu coast between ThoothukudiThoothukudi
Thoothukudi , also known as Tuticorin, is a port city and a Municipal Corporation in Thoothukudi district of the Indian state of Tamil Nadu. Thoothukudi is the headquarters of Thoothukudi District....
and Dhanushkodi were declared the Gulf of Mannar Marine National Park
Gulf of Mannar Marine National Park
The Gulf of Mannar Marine National Park is a protected area of India consisting of 21 small islands and adjacent coral reefs in the Gulf of Mannar in the Indian Ocean. It lies 1 to 10 km away from the east coast of Tamil Nadu, South India for 160 km between Thoothukudi and Dhanushkodi...
. The park and its 10 km buffer zone were declared a Biosphere Reserve
Biosphere reserve
The Man and the Biosphere Programme of UNESCO was established in 1971 to promote interdisciplinary approaches to management, research and education in ecosystem conservation and sustainable use of natural resources.-Development:...
in 1989.
The Gulf of Mannar Biosphere Reserve covers an area of 10,500 km² of ocean, islands and the adjoining coastline. The islets and coastal buffer zone includes beach
Beach
A beach is a geological landform along the shoreline of an ocean, sea, lake or river. It usually consists of loose particles which are often composed of rock, such as sand, gravel, shingle, pebbles or cobblestones...
es, estuaries, and tropical dry broadleaf forests
Tropical and subtropical dry broadleaf forests
The tropical and subtropical dry broadleaf forest biome, also known as tropical dry forest, is located at tropical and subtropical latitudes. Though these forests occur in climates that are warm year-round, and may receive several hundred centimeters of rain per year, they have long dry seasons...
, while the marine environments include seaweed
Seaweed
Seaweed is a loose, colloquial term encompassing macroscopic, multicellular, benthic marine algae. The term includes some members of the red, brown and green algae...
communities, sea grass communities, coral reef
Coral reef
Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps...
s, salt marsh
Salt marsh
A salt marsh is an environment in the upper coastal intertidal zone between land and salt water or brackish water, it is dominated by dense stands of halophytic plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh...
es and mangrove
Mangrove
Mangroves are various kinds of trees up to medium height and shrubs that grow in saline coastal sediment habitats in the tropics and subtropics – mainly between latitudes N and S...
forests.
Marine activities
Pliny the Elder
Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...
(23–79) praised the pearl fishery of the gulf as most productive in the world. Although extraction of natural pearls is considered too expensive in most parts of the world, it is still conducted in the gulf.
The chief seaports on the Gulf of Mannar are Thoothukudi
Thoothukudi
Thoothukudi , also known as Tuticorin, is a port city and a Municipal Corporation in Thoothukudi district of the Indian state of Tamil Nadu. Thoothukudi is the headquarters of Thoothukudi District....
(Tuticorin) in Tamil Nadu, and Colombo
Colombo
Colombo is the largest city of Sri Lanka. It is located on the west coast of the island and adjacent to Sri Jayawardenapura Kotte, the capital of Sri Lanka. Colombo is often referred to as the capital of the country, since Sri Jayawardenapura Kotte is a satellite city of Colombo...
in Sri Lanka. While these ports can accommodate deep-draft vessels, the shallow Palk Strait can only accommodate small shallow-draft vessels. In July 2005, the Indian Government took preliminary steps to go ahead with the Sethusamudram Shipping Canal Project
Sethusamudram Shipping Canal Project
Sethusamudram Ship Channel Project proposes linking the Palk Bay and the Gulf of Mannar between India and Sri Lanka by creating a shipping channel through the shallow sea sometimes called Setu Samudram, and through the chain of islands variously known as Ramar Palam , ram sethu and Adam's Bridge...
, which would create a deep channel linking the Gulf of Mannar to the Bay of Bengal
Bay of Bengal
The Bay of Bengal , the largest bay in the world, forms the northeastern part of the Indian Ocean. It resembles a triangle in shape, and is bordered mostly by the Eastern Coast of India, southern coast of Bangladesh and Sri Lanka to the west and Burma and the Andaman and Nicobar Islands to the...
. Project boosters emphasize the benefits of a direct shipping route that connects India's east and west coasts without the long trip around Sri Lanka; environmentalists have warned against the grave damage such a project could cause to the sea life and fisheries of the Palk Strait and the Gulf.