Laccadive Sea
Encyclopedia
The Laccadive Sea or Lakshadweep Sea is a body of water bordering India
(including its Lakshadweep
islands), the Maldives
, and Sri Lanka
. It is located to the west of Kerala
. This warm sea has a stable water temperature through the year and is rich in marine life, with the Gulf of Mannar
alone hosting about 3,600 species.
defines the limits of the Laccadive Sea as follows:
. There are numerous coral reef
s in the sea, such as the Lakshadweep islands which are made up of atoll
s and contain 105 coral species.
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. Also collected in large numbers are Shankha
mollusks (Xancus pyrum) whose shells are used as a ritual
and religious object. Other mollusks of the sea are either too scarce or not popular in the Indian society and therefore have no commercial value.
Another traditional occupation in the Laccadive Sea is fishing. The annual fish catch is 2,000 to 5,000 tonnes from the Lakshadweep islands, which is mostly constituted by tuna (about 70%) and shark. Perch
es, halfbeak
s, Carangidae
, needlefish
and rays are also caught near the reefs. Shrimp
, Achelata
and small fish, such as Sprattus
, Pomacentridae
and Apogonidae
are widely used as a bait by the Laccadive islanders.
With about 3,600 species of flora and fauna, the Gulf of Mannar is regarded as one of the richest marine biological resources in the world. Of these 3,600 species, 44 are protected, 117 are corals, 79 crustaceans, 108 sponges, 260 mollusks, 441 fin fishes, 147 seaweeds and 17 mangroves. In 1986, a group of 21 islands and nearby waters with the total area of 560 km² were declared Gulf of Mannar Marine National Park
. The park and its buffer zone were designated as 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, and is the largest such reserve in India. Most of its area is restricted for outsiders and the access of boats is subject to strict rules, but local people continue fishing activities which they crucially depend on. From about 150,000 people living in the buffer zone and more than 70% of them depend on the coastal marine resources. There are about 125 fishing villages with 35,000 active fishers and 25,000 divers for sea cucumber
s in the area, about 5,000 women collect seaweed. About 106,000 tonnes of fish were produced in the gulf in 2006, mostly oil sardines
(Sardinella longiceps), lesser sardines (Sardinella
spp.), ponyfish
(Letognathus sp.), mackerel, penaeid shrimp
, perches, squid (Sepioteuthis arctipinni), deep-sea lobster (Puerulus sewelli), crab (Varuna littorata), skate
s and rays. The seaweed collection aims at shallow-water species Gelidiella acerosa (marikozhundu passi), Gracilaria edulis (Agarophytes, Kanchi passi), Sargassum
spp. (kattakorai), Turbinaria (Alginophyte, Pakoda passi) and Ulva lactuca
, and is conducted between October and March. Because of National Park related restrictions, the production of seaweeds declined from 5,800 tonnes (dry weight) in 1978 to 3,250 tonnes in 2003.
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...
(including its Lakshadweep
Lakshadweep
Lakshadweep , formerly known as the Laccadive, Minicoy, and Amindivi Islands, is a group of islands in the Laccadive Sea, 200 to 440 km off the coast of the South West Indian state of Kerala...
islands), the Maldives
Maldives
The Maldives , , officially Republic of Maldives , also referred to as the Maldive Islands, is an island nation in the Indian Ocean formed by a double chain of twenty-six atolls oriented north-south off India's Lakshadweep islands, between Minicoy Island and...
, and 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...
. It is located to the west of Kerala
Kerala
or Keralam is an Indian state located on the Malabar coast of south-west India. It was created on 1 November 1956 by the States Reorganisation Act by combining various Malayalam speaking regions....
. This warm sea has a stable water temperature through the year and is rich in marine life, with the Gulf of Mannar
Gulf of Mannar
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...
alone hosting about 3,600 species.
Extent
The International Hydrographic OrganizationInternational Hydrographic Organization
The International Hydrographic Organization is the inter-governmental organisation representing the hydrographic community. It enjoys observer status at the UN and is the recognised competent authority on hydrographic surveying and nautical charting...
defines the limits of the Laccadive Sea as follows:
On the West. A line running from Sadashivgad Lt.SadashivgadSadashivgad is a fort located in Karwar, Uttara Kannada district, in the state of Karnataka in India. Significant and picturesque, the fort is now a popular tourist destination located by the Kali river bridge, which has been built at the confluence of the river and the Arabian Sea...
on West Coast of India (14°48′N 74°07′E) to Corah DivhCora DivhCora Divh, also called Coradeeve or Little Bassas de Pedro Bank , is a submerged bank or sunken atoll belonging to the Amindivi Subgroup of islands of the Union Territory of Lakshadweep, India. It is the third largest feature of Lakshadweep, after Bassas de Pedro and Sesostris Bank, with a lagoon...
(13°42′N 72°10′E) and thence down the West side of the Laccadive[ LakshadweepLakshadweepLakshadweep , formerly known as the Laccadive, Minicoy, and Amindivi Islands, is a group of islands in the Laccadive Sea, 200 to 440 km off the coast of the South West Indian state of Kerala...] and MaldiveMaldivesThe Maldives , , officially Republic of Maldives , also referred to as the Maldive Islands, is an island nation in the Indian Ocean formed by a double chain of twenty-six atolls oriented north-south off India's Lakshadweep islands, between Minicoy Island and...
Archipelagos to the most Southerly point of Addu AtollAddu AtollAddu City is a city in Maldives consisting of the inhabited islands of the southernmost atoll of the archipelago....
in the Maldives.
On the South. A line running from Dondra Head
Dondra HeadDondra Head is a cape on the extreme southern tip of Sri Lanka, in the Indian Ocean, near the small town of Dondra near Galle, Southern Province, Sri Lanka...
in Ceylon [Sri Lanka] to the most Southerly point of Addu Atoll.
On the East. The West coasts of Ceylon and India.
On the Northeast. Adams Bridge (between India and Ceylon).
Hydrology
Water temperature is rather constant through the year, averaging 26–28 °С in summer and 25 °С in winter. Salinity is 34‰ (parts per thousand) in the center and northern part and up to 35.5‰ in the south. The coasts are sandy but the deeper parts are covered in siltSilt
Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar. Silt may occur as a soil or as suspended sediment in a surface water body...
. There are numerous 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 in the sea, such as the Lakshadweep islands which are made up of atoll
Atoll
An atoll is a coral island that encircles a lagoon partially or completely.- Usage :The word atoll comes from the Dhivehi word atholhu OED...
s and contain 105 coral species.
Fauna and human activities
Pearl
A pearl is a hard object produced within the soft tissue of a living shelled mollusk. Just like the shell of a mollusk, a pearl is made up of calcium carbonate in minute crystalline form, which has been deposited in concentric layers. The ideal pearl is perfectly round and smooth, but many other...
banks of Pinctada radiata
Pearl oyster
Pearl oysters are saltwater clams, marine bivalve molluscs of the genus Pinctada in the family Pteriidae. They have a strong inner shell layer composed of nacre, also known as "mother of pearl"....
and Pinctada fucata for at least two thousand years. Pliny the Elder
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. Also collected in large numbers are Shankha
Shankha
Shankha bhasam , also spelled and pronounced as Shankh and Sankha, is a conch shell of ritual and religious importance in Hinduism and Buddhism. It is the shell of a large predatory sea snail,Turbinella pyrum found in the Indian Ocean....
mollusks (Xancus pyrum) whose shells are used as a ritual
Ritual
A ritual is a set of actions, performed mainly for their symbolic value. It may be prescribed by a religion or by the traditions of a community. The term usually excludes actions which are arbitrarily chosen by the performers....
and religious object. Other mollusks of the sea are either too scarce or not popular in the Indian society and therefore have no commercial value.
Another traditional occupation in the Laccadive Sea is fishing. The annual fish catch is 2,000 to 5,000 tonnes from the Lakshadweep islands, which is mostly constituted by tuna (about 70%) and shark. Perch
Perch
Perch is a common name for fish of the genus Perca, freshwater gamefish belonging to the family Percidae. The perch, of which there are three species in different geographical areas, lend their name to a large order of vertebrates: the Perciformes, from the Greek perke meaning spotted, and the...
es, halfbeak
Halfbeak
The halfbeaks are a geographically widespread and numerically abundant family of epipelagic fish inhabiting warm waters around the world. The family Hemiramphidae is divided into two subfamilies, the primarily marine Hemiramphinae and the freshwater or estuarine Zenarchopterinae...
s, Carangidae
Carangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...
, needlefish
Needlefish
Needlefish are piscivorous fishes primarily associated with very shallow marine habitats or the surface of the open sea. Some genera include species found in marine, brackish, and freshwater environments while a few genera are confined to freshwater rivers and streams, including Belonion,...
and rays are also caught near the reefs. Shrimp
Shrimp
Shrimp are swimming, decapod crustaceans classified in the infraorder Caridea, found widely around the world in both fresh and salt water. Adult shrimp are filter feeding benthic animals living close to the bottom. They can live in schools and can swim rapidly backwards. Shrimp are an important...
, Achelata
Achelata
The Achelata is an infra-order of the reptant Decapoda. It contains the spiny lobsters , the slipper lobsters and the furry lobsters...
and small fish, such as Sprattus
Sprattus
Sprattus is a genus of small oily fish of the family Clupeidae. One can find many varieties served from the Iberian peninsula to the Caucasus. They are commonly fried and eaten in British and Bulgarian cuisine. In northern and north-eastern Europe, European sprats are commonly smoked and preserved...
, Pomacentridae
Pomacentridae
Pomacentridae are a family of perciform fish, comprising the damselfishes and clownfishes. They are primarily marine, while a few species inhabit freshwater and brackish environments . They are noted for their hardy constitutions and territoriality...
and Apogonidae
Apogonidae
Cardinalfishes are a family, Apogonidae, of ray-finned fishes. They are found in the Atlantic, Indian, and Pacific oceans, they are chiefly marine, but some species are found in brackish water...
are widely used as a bait by the Laccadive islanders.
With about 3,600 species of flora and fauna, the Gulf of Mannar is regarded as one of the richest marine biological resources in the world. Of these 3,600 species, 44 are protected, 117 are corals, 79 crustaceans, 108 sponges, 260 mollusks, 441 fin fishes, 147 seaweeds and 17 mangroves. In 1986, a group of 21 islands and nearby waters with the total area of 560 km² were declared 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 buffer zone were designated as 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, and is the largest such reserve in India. Most of its area is restricted for outsiders and the access of boats is subject to strict rules, but local people continue fishing activities which they crucially depend on. From about 150,000 people living in the buffer zone and more than 70% of them depend on the coastal marine resources. There are about 125 fishing villages with 35,000 active fishers and 25,000 divers for sea cucumber
Sea cucumber
Sea cucumbers are echinoderms from the class Holothuroidea.They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. Sea cucumbers are found on the sea floor worldwide. There are a number of holothurian species and genera, many of which are targeted...
s in the area, about 5,000 women collect seaweed. About 106,000 tonnes of fish were produced in the gulf in 2006, mostly oil sardines
Indian Oil Sardine
Indian Oil Sardine is a species of ray-finned fish in the genus Sardinella.Sardinella longiceps is one of the two most important commercial fishes in India . The Indian Oil Sardine is one of the more regionally limited species of Sardinella and can be found in the northern regions of the Indian...
(Sardinella longiceps), lesser sardines (Sardinella
Sardinella
SardinellaSardinella is a genus of fishes in the family Clupeidae. This genus currently contains 21 recognized species. These fish are generally coastal, schooling fish, and abundant in warmer waters. They can be found nearly anywhere in the tropic and subtropic oceans of the World...
spp.), ponyfish
Ponyfish
The ponyfishes also known as slipmouths or slimys are a small family, Leiognathidae, of fishes in the order Perciformes. They inhabit marine and brackish waters in the Indian Ocean and West Pacific....
(Letognathus sp.), mackerel, penaeid shrimp
Penaeidae
Penaeidae is a family of prawns, although they are often referred to as penaeid shrimp. It contains many species of economic importance, such as the tiger prawn , whiteleg shrimp, Atlantic white shrimp and Indian prawn. Many prawns are the subject of commercial fishery, and farming, both in marine...
, perches, squid (Sepioteuthis arctipinni), deep-sea lobster (Puerulus sewelli), crab (Varuna littorata), skate
Skate
Skates are cartilaginous fish belonging to the family Rajidae in the superorder Batoidea of rays. There are more than 200 described species in 27 genera. There are two subfamilies, Rajinae and Arhynchobatinae ....
s and rays. The seaweed collection aims at shallow-water species Gelidiella acerosa (marikozhundu passi), Gracilaria edulis (Agarophytes, Kanchi passi), Sargassum
Sargassum
Sargassum is a genus of brown macroalga in the order Fucales. Numerous species are distributed throughout the temperate and tropical oceans of the world, where they generally inhabit shallow water and coral reefs. However, the genus may be best known for its planktonic species...
spp. (kattakorai), Turbinaria (Alginophyte, Pakoda passi) and Ulva lactuca
Ulva lactuca
Ulva lactuca Linnaeus, a green alga in the division Chlorophyta, is the type species of the genus Ulva, also known by the common name sea lettuce.-Description:...
, and is conducted between October and March. Because of National Park related restrictions, the production of seaweeds declined from 5,800 tonnes (dry weight) in 1978 to 3,250 tonnes in 2003.