Biodiversity of gulf of mannar

1. 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

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
Advantage
s1.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
5. Augmentation of external infrastructure
like road/rail, water & water supply
6. 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 km2, from Okha
to Jodiya was declared Marine
Sanctuary.
 1982-a core area of 110 km2 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

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.

34.  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.

35. 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