Gulf of mannar

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1. Presentation by Livi Wilson Ph.D Scholar Biodiversity of Gulf of Mannar

2. Gulf of Mannar   large shallow bay lies between the southeastern tip of  India  and the west coast of  Sri Lanka . The estuaries of  Thamirabarani River  of south India and the  Aruvi Aru River  of Sri Lanka drain into the Gulf .

3. GEOGRAPHICAL LOCATION Palk Strait Palk Bay Adam’s Bridge Gulf of Mannar

4. About gulf of mannar Some features: 1986- declared the  Gulf of Mannar Marine National Park . 1989-The park and its 10 km buffer zone were declared a  Biosphere Reserve   First marine Biosphere Reserve in South East Asia, a chain of 21 islands ( 10,500 km²) Home to 3,600 rare Species of flora and fauna like fishes, coral reefs, sea horse, algae, marine plants

5. The islets and coastal buffer zone includes   Beaches Estuaries   Tropical dry broadleaf forests The marine environments include   Seaweed  communities Sea grass communities   Coral reefs Salt marshes     Mangrove  forests

6. Gulf of Mannar reefs lie along the 140 km stretch between Tuticorin and Rameswaram latitude 8°47' N and 9° 15' N longitude 78° 12' E and 79° 14'E. Mannar Barrier reef which is about 140 km long and 25 km wide between Pamban and Tuticorin The islands have fringing coral reefs and patch reefs around them Total area occupied by reef and its associated features is 94.3 sq km.

7. Reef diversity and resources 96 species of corals belonging to 36 genera The most commonly occurring genera of corals are  Acropora , Montipora   and   Porites . the reefs also harbour boring sponges, molluscs , worms, echinoderms, common shrimps, and fish ornamental fishes belonging to the family  Chaetodontidae , (butterfly fish);  Amphiprion spp  (clown fish),  Holocentrus spp  (squirrel fish),  Scarus   spp (parrot fish),  Lutjanus   spp (snapper fish) and  Abudefduf saxatilis   (sergeant Major) are abundant. ( Kumaraguru , 1997).

8. Extensive sea grass beds are present; green turtles, olive ridley turtles and dugongs are dependent on the sea grasses. A unique endemic species of Balanoglossus , a living fossil that is considered a link between vertebrates and invertebrates was recorded from this region. Annual productivity in coral reefs being 2000-5000 gc / sq.m /yr.

9. Sea Grass Ecosystem the sole marine representatives of the Angiospermae feeding grounds of the herbivores Green Turtle and the sea cow Sea grass binds sediments and prevent erosion. Of the 52 species of sea grasses recorded worldwide, 12 species are recorded in Gulf of Mannar . Sea grasses absorb sediments thereby protecting coral reefs during storms and cyclones

10. Mangrove Ecosystem salt tolerant forest ecosystems, which support fisheries and protect the coastal zones, thus helping the marine coastal economy and environment. 9 species and 7 associated species were found in Gulf of Mannar . The two common mangrove species Rhizopora sp and Avecinia sp.

11. Dolphins are a common in some parts of the Gulf. Thousands of migratory olive ridley sea turtles pass through the Gulf to their mass nesting or arribada in Gahirmatha Orrisa . The Krusadai Island in the Mandapam Group of islands is of biological significance in this area due to its diversity. due to destructive fishing and pollution, coral reefs, dolphins, Dugongs (Dugong Dugon ), whales and sea cucumbers are among the species which figure in the endangered list

12. Overall diversity Families Species Phytoplankton 126 Zooplankton 360 Forominifera 51 Sponges 275 Corals 128 Gorgonids 14 Polochaeta 75 Nematoda 9 Crustacea 368 Molluscus 731 Echinodermata 264 Hemichordata 1 Capture fishes 441 Ornamental fishes 100 Sea turtles 5 Sea weed 147 Sea grass 52 Mangroves 16

13. Fishery Resources Marine capture fisheries are the major economic activity in Gulf of Mannar 441 species have been recorded in Gulf of Mannar .(2,200 fish species distributed in Indian waters) Gulf of Mannar is one of the best regions in the Indian subcontinent in fish biodiversity richness. Shore seines, boat seines, trawl nets and hook lines are the principal gear operated.

14. Setusamudram Advantages 1.Saving of upto 30 hours or 424 nautical miles 2. Considerable savings to vessels and earnings of foreign exchange. 3. Beneficial for naval defence 4. Increased economic activities like transportation, fishing and ancillary industries Augmentation of external infrastructure like road/rail, water & water supply A stable system with least maintenance cost

15. Environmental Aspect Some of the flora and fauna of this region Extinction of more than 700 fish varities More susceptible to future cyclone and tsunamis Disastrous effect on marine life, fisheries, virgin beaches in case of an accident Whether to go for short term financial gains or long term ecological balance ?

16. Biodiversity of the Gulf Of Kutch

17. The Gulf of Kutch is situated in Saurashtra in the western State of Gujarat in India. separates the landmass of Saurashtra from the northern landmass of Kutch. shallow water basin about 60 m deep at the mouth, sloping up to a depth of less than 20 m at the head, visited by 'mixed semidiurnal' tides

18. Gulf of Kutch Marine National Park It is the first national marine park in India. situated on the southern shore of the Gulf of Kutch in the Jamnagar District of Gujarat state. 1980-an area of 270 km 2 , from Okha to Jodiya was declared Marine Sanctuary. 1982-a core area of 110 km 2 was declared Marine National Park under the provisions of the Wildlife (protection) Act(1972)

19. Contd.. Protected areas include about an archipelago made up of 42 islands. fauna found here: coral, dugong and the finless porpoise. Biodiversity and Conservation challenges: extraction of corals and sands by cement industries, increased turbidity of water, oil refineries, chemical industries and mechanized fishing boats.

20. Biodiversity Excellent Coral Reefs 37 species of Hard & Soft Corals 70 species of Sponges 27 species of Prawns 30 species of Crabs 200 species of Molluscs Endangered Sea Turtles like the Green Sea, Oliver Riddley & Leather Back. 3 Speices of Sea Mammals 94 species of Water Birds 78 species of terrestrial birds 108 species of brown, green & red Algae

21. Coral Reefs fringing reefs, platform reefs, patch reefs and coral pinnacles. There are some 40 islands with patchy coral formation of which the largest is Pirotan Island . 37 species of hard corals 12 species of soft corals the total reef area in the Gulf decreased from 217 sq km in 1975 to 123 sq km in 1986; a net loss of 43 per cent Coral dredging by a cement company is held to be largely responsible for the heavy siltation

22. Locality Genera species Gulf of Kutch* 24 37 West Coast Patches* 17 29 Lakshadweep Islands 37 103 Palk bay and Gulf of Mannar 36 96 Tuticorin 19 21 Andaman Islands 31 82 Nicobar Islands 43 103 Total for India* 37 199 Source: Bakus , G.J (1994) and * Pillai , G (1996). coral

23. Mangroves Jamnagar District has an area of 665.9 sq km mangrove cover predominantly of scrubby and sparse type Mangrove species such as Rhizophora , Ceriops and Aegiceros , which are reported to have once existed in the region, are now rare, while the species Bruguiera is extinct Since the early 1990s, mangrove cover has been increasing in Gujarat, from 397 sq km in1991 to 960 sq km in 2003. - Jamnagar and Kutch - contributed to more than 90 per cent of the overall increase in mangrove cover.

24. Fisheries Jamnagar contributed 10.01 per cent of the total marine fish production in the State. W. Pomfret B. Pomfret Bom. Duck Thread fin Jew fish Hilsa Clupeids Coilia Shark

25. Malabar upwelling

26. Upwelling occur where the wind blows parallel to a coastline.  divergence draws water from below into the surface Ekman layer in a process known as  upwelling Upwelling in coastal waters brings nutrients toward the surface. Phytoplankton reproduce rapidly in these conditions, and grazing zooplankton also multiply and provide abundant food supplies for nekton. Some of the world’s richest fisheries are found in regions of  upwelling —for example, the temperate waters off Peru

27. Upwelling in these regions cools the surface water and brings  nutrient -rich subsurface water into the sunlit layer of the ocean, resulting in a biologically productive region.

28. The Malabar upwelling zone along Kerala coast (south-west coast of India) is one of the important upwelling systems of the world ( Bakun et al., 1998) The Malabar coast of India is rich in primary (660 mg C m2/ day) and secondary (10–57 mgC m2 /day) production and contributes nearly 50% of the total Indian marine fish landings ( Vivekanandan et al., 2003; Smith and Madhupratap , 2005)

29. Field and satellite-derived oceanographic data have shown that coastal upwelling occurs during July–September with a peak in August resulting in high nutrient concentrations and biological productivity along the coast. The striking feature of the Malabar upwelling zone is the predominance of pelagic resources such as oil sardine ( Sardinella longiceps ) and Indian mackerel ( Rastrelliger kanagurta )

30. The catch of small pelagics , especially that of the oilsardine increased from1, 554 t in 1994 to 2,50, 469 t in 2007 in the Malabar upwelling zone off Kerala, India. The coastal upwelling index (CUI) during south-west monsoon increased by nearly 50% during the period 1998 to 2007. This substantial increase in coastal upwelling index elevated chlorophyll a concentration during monsoon which resulted in an increase of over 200% in annual average chlorophyll a concentration. The increasing coastal upwelling index and chlorophyll a during monsoon sustained an increasing catch of oilsardine during postmonsoon season. The responses of lesser sardine and Indian mackerel, which are midlevel carnivores, were different.

31. The prawn fishery is supported chiefly by Melapenaeus dobsoni ( Poovalan chemmeen ). Parapenaeopsis stylifera ( Karikkadi chemmeen ) and Penaeus indicus ( Naaran chemmeen ) also occur in smaller quantities. In the case of M. dobsoni , sizes ranging between 90-105 mm dominate in the fishery.

32. References Influence of coastal upwelling on the fishery of small pelagics off Kerala, south-west coast of India U. MANJUSHA, J. JAYASANKAR, R. REMYA, T. V. AMBROSE AND E. VIVEKANANDAN The Gulf of Kutch Marine National Park and Sanctuary: A Case Study By Nilanjana Biswas Coastal an marine wetlands of India by K.Venkataraman Resources information system for Gulf of Mannar      Government of India   Environmental Impact Assessment for Proposed Sethusamudram Ship Canal Project Tuticorin Port Trust