Gulf of Mannar Marine National Park is a beautiful place, located in the Ramanathpuram & Tuticorin districts of the state of Tamil Nadu. The park is the core area of the Gulf of Mannar Biosphere Reserve. This is the first marine Biosphere Reserve in India. It was established in the year of 1980. Total area of the park is 6.23 Km 2. The Gulf of Mannar Marine National Park is a protected area of India consisting of 21 small islands (islets) 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, India for 160 km between Thoothukudi (Tuticorin) and Dhanushkodi. The Gulf of Mannar (/ m ə ˈ n ɑːr / mə- NAR) is a large shallow bay forming part of the Laccadive Sea in the Indian Ocean. It lies between the west coast of Sri Lanka and the southeastern tip of India, in the Coromandel Coast region. The Gulf of Mannar Marine National Park (GOM MNP) comprises of 21 islands surrounded by coral reef areas along with shallow water habitat of unique marine biodiversity. Sea horse, Sea Cow, Dolphins, sea cucumbers etc. are seen here.  9.267°N 77.433°E  / 9.267; 77.433 Ramanathapuram District is an administrative district of Tamil Nadu state in southern India. The town of Ramanathapuram is the district headquarters. Ramanthapuram District has an area of 4123 km 2.

1. Biodiversity of Gulf of Mannar
Ashish sahu

2. Introduction
• In the Indian Ocean, between South East
of India and West of Sri Lanka
• Situated between Rameswaram (79° 14' East
Longitude and 9°14' North Latitude) and
Tuticorin (78° 9' East Longitude 8°48' North
Latitude) on the south-eastern coast of the
country (Tamilnadu)
• The gulf is 80–170 miles (130–275 km) wide and
100 miles (160 km) long
• It has a chain of 21 islands stretching from
Mandapam to Tuticorin

4.  Ecosystems such as
- coral reefs
- rocky shores
- sandy beaches
- mud flats
- estuaries
- mangrove forests
- seaweed stretches
- seagrass beds

5. Biodiversity
• Gulf of Mannar is endowed with 3600 species of flora and fauna
• The diverse nature of ecosystems in the Gulf of Mannar supports a
wide variety of significant species including 117 spp. of corals, 641
spp. of crustaceans, 731 spp. of molluscs, 441 spp. of finfishes,
147 species of seaweeds, 160 spp. of phytoplankton , 129 spp. of
zooplankton and 82 spp. of birds
• Apart from above the seasonally migrating marine mammals like
whales, dolphins, porpoises and turtles
• The mangrove habitats in the Gulf of Mannar have 9 different
species of vegetation supporting a variety of marine fauna
including seabirds and sea snakes
• Gulf of Mannar is considered as “Biologists’ paradise”

6. Marine faunal diversity of Gulf of Mannar

7. Conti…

8. Conti…

9. Gulf of Mannar Biosphere Reserve
• 21 islands (GOM) declared as Marine National Park (623 ha) on
10th September 1986 under section 35(1) of the Wildlife
(Protection) Act 1972, for the purpose of protecting marine
wildlife
• Set up as biosphere reserve on 18th February 1989 jointly by the
Government of India and the state of Tamilnadu
• The Gulf of Mannar biosphere reserve has an area of about
10,500 km2
• The same has been recognized as the Man and Biosphere
Programme by UNESCO
• The biosphere reserve and particularly the Marine National Park
of the Gulf of Mannar also gains more importance because of
the alarmingly declining population of the endangered Sea cows

10. Objectives
• To protect wildlife within the Marine National Park
• To safeguard the breeding and feeding grounds of the
endangered and vulnerable fauna and flora
• To gradually eliminate disruptive and destructive activities
affecting the Park Ecosystem
• To conserve the gene pool resources for marine and aquatic
species
• To restore and protect natural vegetation and stabilize the
islands
• To create awareness on conservation and management of the
marine resources in a scientific manner so that there will be
proper socioeconomic development in the region
• To promote judicious and optimal utilization of the resources for
research, education and recreational purposes

11. Magroves in Gulf of Mannar
• Mangroves are present in all the islands in the
Gulf of Mannar
• Manauli island has luxuriant growth of
mangrove vegetation
• Mangrove vegetation which includes the
species of Rhizopora, Avicennia, Bruguiera,
Ceriops and Lumnitzera

12. Algal biodiversity
• There are about 40 species of algae found in the Gulf of
Mannar
• The production of seaweeds in the Gulf of Mannar has been
estimated to occur in 17,125 hectares
• Luxuriant growth of seaweeds is found in Mandapam and
Keelakkarai areas
• The average density of algae in the Gulf of Mannar is 0.11
kg/m2 in wet weight
• Some of the important algae found in the Gulf of Mannar are
Ulva reticulata, Halimeda opuntia and Caulerpa recimosa
• Sargassum sp., Turbinaria sp., Gelidiella acerosa, Padina sp.,
and Gracilaria sp. are used in the production of agar,
cellulose and algin
• The annual harvest of seaweeds in the Gulf of Mannar is
nearly 5,000 to 7,000 tones by dry weight, which involves
more than 1,000 men and 450 women in the business

13. Seagrass
 Total 13 species recorded in the Gulf
 The seagrass beds of Gulf of Mannar are unique
since they provide food source for the endangered
marine mammal Dugong
 Some of the important species of sea grasses in
the Gulf of Mannar are
Enhalus sp.
Thalassia sp.
Halophila sp.
Cymadocea sp.

14. Coral reef
• The coral reef resources of the Gulf of Mannar are
unique
• They grow surrounding all the 21 islands
• They offer shelter to a variety of organisms and protect
the mainland from storms, currents and shore erosion
• Corals fix the energy
• A number of reef animals come to feed on plants and
plankton
• Finfishes like Acanthurids, Nemipterids, Balistids,
Labrids and Chaetodontids spawn in coral reefs

15. Conti…
• Fishing communities are dependent on the coral reef
ecosystem
• It is necessary to conserve and protect this ecosystem
• Towards this, the Government of Tamil Nadu by its order
Number 116 dated 20th May, 1982 prohibited the removal of
corals, dead or alive, from the water
• There are around 137 species of corals belonging to 37 genera
• The species of Acropora, Montipora and Porites are commonly
available in the Gulf
• The algal species of Rhodophyta, Chlorophyta and Bryophyta
are responsible for the high production of calcium carbonate in
the corals through symbiotic zooxanthellae

16. Crustacean diversity
• There are 18 species of shrimps of which 10 are heavily exploited
• Penaeus semisulcatus, P. indicus and P. monodon are commonly available
• 7 species of spiny and sand lobsters
• The lobsters Panulirus homarus, P. ornatus, P. logipes and P. versicolor are
abundant
• The crabs Scylla serrata, Portunus pelagicus and P. sanguinolentus are the
three common species

17. Molluscan diversity
 The pearl oyster fishery is an important one in
the Gulf of Mannar
 Pearl oyster beads are common inTuticorin
region
 6 species of pearl oysters have been reported
in Indian waters
 Natural pearls are obtained from Pinctada
fucata in the Gulf of Mannar
 The fishing season is November to May
 A large number of pearl banks inTuticorin
region are available at a depth of 10-20 meters

18. Conti…
 The cephalopod fisheries of Gulf of Mannar
includes squids and cuttlefishes
 Among the squids Loligo duvaucelli and among the
cuttlefishes Sepia pharaonis, S. aculata and Sepia
inermis form the major fishery of cephalopods
 The sacred chunk (Xancus pyrum) forms an
important fishery in the Gulf of Mannar
 The fishing seasons for chunks are from
September to March
 About 1,000 km2 area of inshore waters of Gulf of
Mannar have been identified as chunk grounds

19.  Sea cucumbers which belong to holothurians
are available in the Gulf of Mannar
 Collected by skin diving, at depths ranging
from 2-10 meters
 The sea cucumbers Holothuria scabra and
Holothuria spinifera have been over-
exploited
 H. scabra is a valuable species for the
preparation of sea cucumber Beech-de-Mer

20. Finfish
• Nearly 441 species of fishes in the Gulf of Mannar
• The common finfishes belong to Clupieds, Leiognathids,
Lethrinids, Perches, Carangids, Seer fishes, Red mullets, Half
beaks, Needle fishes and Elasmobranchs such as sharks and
rays
• There are 15 species of silver bellies in this region of which
four species of Leiognathus are common
• They are L. equulus, L. bindus, L. dussumieri and L. splendens
• 20 species of lethrinids have been reported
• The commonly available species of Lethrinus are L. ornatus,
L. varigatus, L. hark, L. lentjan, L. nebulosus and L. microdon
• The other major contributors to the fishery are Perches,
Nemipterids, Serranids, Lutjanidsand Epinephelids

21. Reptiles
 There are 5 species of turtles which frequent the
Gulf of Mannar
 They are
Chelonia mydas (green turtle)
Caretta caretta (Logger head)
Lepidochelys olivacea (Olive rideley)
Eretomochelys imbricata (Hawk’s bill)
Dermochelys coriacea (leather back turtle)

22. Marine mammals
• The marine mammals of Gulf of Mannar include
11 species of whales
14 species of Dolphins
1 species of Dugong
1 species of porpoise (Phocoenidae)
• Dugong dugon is known as the sea-cow, is an
endangered marine mammal living in the Gulf of
Mannar

23. Major threats gulf of mannar
biodiversity
• Environmental degradation
• Pollution
• Coral bleaching & mining activities
• Increased sedimentation
• Water diversion
• Exotic species & diseases
• Release of hot water from thermal power
plant

24. Managements
• Strict law under the wildlife protection act(1972)
for the Marine Protected Areas
• Prohibit destructive fishing activities
• CRZ notifications (1991)
• CITES act (1973)
• Environment protection act (1986)
• Public awareness
• Community based fishery management
• Participatory approach
• Biodiversity act (2002)
• Reduce pollution load

25. References
 Database on coastal information of Tamil Nadu,
Ramesh, R., Nammalwar, P. and Gowri, V. S., 2008.
Institute of Ocean Management, Anna University,
Tamilnadu
 Handbook of fisheries and aquaculture by ICAR
 Marine biodiversity conservation and management,
Menon N.G. and Pillai C.S.G.

26. Thank you