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| Last Updated:: 01/02/2017

Gulf of Mannar

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Gulf of Mannar
Name of the area
Gulf of Mannar
Place :
Between Thoothukudi and Dhanuskodi
State :
Latitude :
8°47’N and 9°15’N
Longitude :
78°12 ’E and 79°14 ’E
Key Physical Characters
Total reef area
94.3 sq km
2 to 9mts
Transparency :
1 to 3m
Water temperature:
25° to 30°c
Chemical Characters
pH :
7.6 to 8.4
Salinity :
32.4 to 32.8ppt
Dissolved Oxygen :
4.5 to 4.9
Major Flora and Fauna
Benthic Fauna :
Shrimp, lobster, crabs, seacucumber, mollusk, gastropods, polychaetes etc.,
    Name of the species - IUCN status
Heteronema erecta - Not avilabale 
Dentriela cactus - Not availabale
Sigmadocia fibulata - Not Available
Sigmadocia pumila - Not evaluated
Echinodictyum clathrat um -Not evaluated
Microciona aceratoobtusa - Not available
Optulitaspongia rimosa - Threatened
Phycopsis sp. - Not Evaluated
Spirastrella coccinea -Not evaluated
Cliona celiba - Not available
Cliona orientalis - Not available
(Source: Asir Ramesh Ph.D Thesis - 1996)
Syllis sp.
Nereis sp.
Perinereis cultrifera
Eseudo rereis gallapogensis
Eunice atra atra
Eunice antennae
Salbellaria Pectinata
Sabellaria spinulosa
Serpula vermiularisis
Hydroides minax
(Source: Asir Ramesh Ph.D Thesis – 1996)
126 species of phytoplankton were reported (Kannan, 1996).
Diatoms : 97 species (33 genera)
Dinoflagellates : 16 species (6 genera)
Blue-green algae : 7 species (5 genera)
Green algae : 3 species (3 genera)
Others : 3 species (3 genera)
The population density varied from 34000 to 86000 cells / litre.
360 species of zooplankton were reported (CMFRI, 1998).
Planktonic and Larval forms
Copepods 223
Cumacea 10
Amphipods 52
Ostracods 57
Isopods 18
Decapod larvae 8
Commercially Important Shell fishes
Penaeid and non-penaeid shrimps, lobsters, crabs, cephalopods, bivalves and gastropods etc.,
Commercially Important Fin Fishes
441 species of fishes have been recorded, among these 200 species are commercial important including sardines, mackerel, anchovies, seerfishes, tunas, ribbon fishes,
elasmobranchs, perches, catfishes, silver bellies, goatfish, lizard fishes, ribbon fishes, mullets, barracudas etc.,
Ornamental Fish
128 species of ornamental fishes were recorded in Gulf of
Mannar, of which 91 species were recorded around the Mandapam group.
The dominant species were Chaetodontidae, Pomacentridae, Balistidae and Apogonidae.
Family : Pomacentridae
Abudefduf bengalensis -Not evaluated
Abudefduf saxatilis -Least concern
Abudefduf septemfasciatus - Not evaluated
Abudefduf sexfasciatus -Not available
Abudefduf vaigiensis - Not evaluated
Amphiprion allardi - Not evaluated
Amphiprion clarkii - Not evaluated
Amphiprion sebae - Not evaluated
Chromis dimidiata -Not evaluated
Chromis viridis- Not evaluated
Dascyllus aruanus - Not evaluated
Dascyllus trimaculatus - Not evaluated 
Plectroglyphidodon dickii - Not evaluated
Pomacentrus trilineatus - Not evaluated
Pomacentrus vaiuli - Not evaluated
Stegastes fasciolatus - Not evaluated
Stegastes nigricans - Not evaluated
Family : Pomacanthidae
Pomacanthus annularis - Least concern 
Pomacanthus imperator - Least concern
Pomacanthus semicirculatus - Least concern
Pomacanthus sexstriatus - Least concern
Family : Acanthuridae
Acanthurus leucosternon - Least concern
Acanthurus lineatus - Least concern
Acanthurus nigricans - Least concern
Acanthurus nigricauda - Least concern
Acanthurus triostegus - Least cooncern
Acanthurus xanthopterus -Least concern
Aethaloperca rogaa - Data deficient 
Zebrasoma desjardinii - Least concern
Ctenochaetus striatus - Least concern
Family : Gobiidae
Amblyeleotris guttata - Not evaluated
Amblyeleotris steinitzi - Not available
Amblygobius decussatus - Not evaluated
Amblygobius phalaena -Not evaluated
Family : Apogonidae
Apogon compressus - Least concern
Apogon fraenatus - Not available
Apogon kallopterus - Not evaluated
Apogon nigricans - Not evaluated
Apogon nigrofasciatus -Not evaluated
Apogon novemfasciatus - Not evaluated
Cheilodipterus quinquelineatus -Not evaluated
Family : Tetraodontidae
Arothron meleagris - Least concern
Arothron nigropunctatus - Least concern
Canthigaster bennetti - Least concern
Canthigaster solandri - Least concern
Canthigaster valentini - Least concern
Family : Balistidae
Balistapus undulatus - Not evaluated
Balistoides viridescens - Not evaluated
Rhinecanthus aculeatus -Not evaluated
Rhinecanthus rectangulus - Not evaluated 
Family : Caesionidae
Caesio cuning - Not evaluated
Caesio teres - Not evaluated
Caesio xanthonata - Not evaluated
Family : Caracanthidae
Caracanthus maculatus - Not evaluated
Caracanthus unipinna - Not evaluated
Carangoides malabaricus -Not evaluated
Family : Carangidae
Caranx ignobilis - Not evaluated 
Caranx melampygus -  Not evaluated
Caranx sexfasciatus - Least concern
Gnathanodon speciosus - Not evaluated
Family : Chaetodontidae
Chaetodon auriga - Least concern
Chaetodon collare - Least concern
Chaetodon melannotus - Least concern
Chaetodon meyeri - Least concern
Chaetodon octofasciatus - Least concern
Chaetodon plebius - Least concern
Chaetodon trifascialis - Near threatened
Chaetodon trifasciatus - Least concern
Chaetodon unimaculatus - Least concern
Chaetodon vagabundus - Least concern
Heniochus acuminatus - Least concern
Heniochus intermedius - Least concern
Cheilinus trilobatus - Least concern
Cheilinus undulatus - Endangered
Chrysiptera unimaculata - Least concern
Diodon hystrix - Least concern
Diodon liturosus - Not evaluated
Ecsenius midas - Least concern
Family : Serranidae
Epinephelus fasciatus - Least concern
Epinephelus lanceolatus - Vulnerable
Epinephelus tauvina - Data deficient 
Cephalopholis boenak - Least concern
Family : Fistulariidae
Fistularia commersonii - Not evaluated
Family : Muraenidae
Gymnothorax favagineus - Not evaluated
Gymnothorax fimbriatus - Not evaluated
Gymnothorax flavimarginatus - Not evaluated
Gymnothorax meleagris - Not evaluated
Gymnothorax tessellata - Not evaluated
Gymnothorax undulatus - Not evaluated
Echidna catenata - Least concern
Family : Labridae
Labroides bicolor - Least concern
Labroides dimidiatus - Least concern
Thalassoma amblycephalum - Least concern
Thalassoma hardwickei - Least concern
Thalassoma lunare - Least concern
Halichoeres hortulanus - Least concern
Halichoeres scapularis - Least concern
Hologymnosus doliatus - Least concern
Family : Lethrinidae
Lethrinus harak - Not evaluated
Lethrinus nebulosus - Not evaluated
Family : Lutjanidae
Lutjanus biguttatus - Not evaluated
Lutjanus decussatus - Not available
Lutjanus fulviflamma - Not evaluated
Lutjanus fulvus - Not evaluated
Lutjanus kasmira -Not evaluated
Family : Blennidae
Meiacanthus atrodorsalis - Least concern
Family : Holocentridae
Myripristis adusta - Not evaluated
Myripristis vittata -Not evaluated
Neoniphon sammara - Not evaluated
Ostracion cubicus - Not evaluated
Ostracion meleagris - Not evaluated
Family : Mullidae
Parupeneus barberinoides - Not evaluated
Parupeneus barberinus - Not evaluated
Parupeneus bifasciatus - Not evaluated 
Family : Pemoheridae
Pempheris vanicolensis - Not evaluated
Plagiotremus rhinorhynchos -Least concern
Family : Ephippidae
Platax orbicularis - Not evaluated
Platax pinnatus - Not evaluated
Platax teira - Not evaluated
Family : Scorpaenidae
Pterois antennata - Not evaluated
Pterois volitons -Threatened
Family : Holocentridae
Sargocentron cornutum - Not evaluated
Sargocentron diadema -Not evaluated
Sargocentron rubrum - Not evaluated
Sargocentron seychellense - Not evaluated
Sargocentron violaceum - Not evaluated
Family : Scaridae
Scarus frenatus - Least concern
Scarus ghobban - Least concern
Scarus sordidus - Least concern
147 sp. of seaweeds, 13 sp. of seagrass etc.,
Endangered species
Turtules, Seahorse, Sharks, Dolphins, Whales, Dugongs, etc.,
Archeologically/Ecologically Important Places
No. of. Islands
Environmental status
Associated ecosystem
Seaweed, seagrass, pearl banks, sockred chank bed, mangroves, estuaries, mudflats and beaches etc.,
Cymodocea serrulata - Least concern
Cymodocea rotundata - Least concern
Syringodium isoetifolium - Least concern
Halodule uninervis - Least concern
Halodule ovalis - Least concern
Halophila ovata - Least concern
Thalassia hemprichii - Least concern
Enhalus acoroides - Least concern
Halophila stipulacea - Least concern
Halophila decipiens - Least concern
Halophila beccarii - Vulnerable
Halodule pinifolia - Least concern
Avicennia marina - Least concern
Rhizophora mucronata - Least concern
Ceriops tagal - Least concern
Bruguiera cylindrica - Least concern
Lumnitzera racemosa - Least concern
Pemphis acidula - Least concern
Excoecaria agallocha -Least concern
Aegiceras corniculatum - Least concern
Rhizophora apiculata - Least concern
Associated Species
Salvadora persica - Not assessed
Pandanus sp. - Vulnerable
Sesuvium sp. - Least concern
Scaevola plumieri -Threatened
Suaeda sp. - Least concern
Salicornia brachiata - Lower risk near threatened
Thespesia populnea - Threatened
Gross average productivity in benthic floor
Major threats
Nature Calamities, Industrial pollution(Ash), liquid effluent, mining, fishing,
diseases etc.,
Microbes isolated from the diseased corals
Viblio sp. - Not available
Beggiatoa sp. - Not available
Desuefovibrio sp. -Not available
Achrobacter sp. - Not available
Rseudomonas sp. Not available
Bacillus sp. - Not available
Coryne bacterium sp. - Not available
Flavobacterium sp. -Not available 
Phormidium corallytiaum - Not available
P. tenue - Not available
Lyngbya sp. - Not available
Spirulina subsala - Not available
Plectonema terebraus -Not available
Oscillatoria sp. - Not available
Microcystis sp. - Not evaluated 
Dark brown coloured sporulating fungus (Source : R.Balasubramanian- 2003)
Corals recorded
117 species recorded
Acropora corymbosa - Least concern
Acropora cytheria - Least concern
Acropora diversa -  Near threatened
Acropora formosa - Near threatened
Acropora humilis - Near threatened
Acropora hyacinthus - Near threatened
Acropora indica - Not evaluated
Acropora micropththalma - Least concern
Acropora millepora - Near threatened
Acropora nobilis - Least concern
Acropora variabilis - Data deficient
Acropora valenciennesi - Least concern
Astreopora myriophthalma - Least concern
Montipora digitata - Least concern
Montipora divaricata - Least concern
Montipora exerta - Not avaliable
Montipora foliosa - Near threatened
Montipora granulosa - Not evaluated
Montipora hispida - Least concern
Montipora jonesi - Least concern
Montipora manauliensis - Least concern
Montipora monasteriata - Least concern
Montipora spumosa - Least concern
Montipora subtilis - Least concern
Montipora tuberculosa - Least concern
Montipora turgescens - Least concern
Montipora venosa - Near threatened 
Montipora verrucosa - Least concern
Montipora verrilli - Data deficient
Pachyseris rugosa - Vulnerable
Pavona decussata - Vulnerable
Pavona divaricata - Not evaluated
Pavona duerdeni - Least concern
Pavona varians - Least concern
Heterocyathus aequicostatus - Least concern
Paracyathus profundus - Not evaluated
Polycyathus verrilli - Not evaluated
Balanophyllia affinis - Critically endangered
Endopsamnia philippinensis -Critically endangered
Dendrophyllia coarctata - Not evaluated
Dendrophyllia indica - Not evaluated
Heteropsammia michelini - Least concern
Tubastrea aurea - Not evaluated
Turbinaria crater - Not evaluated
Turbinaria peltata -Vulnerable
Turbinaria undata - Not evaluated
Cyphastrea microphthalma - Least concern
Cyphastrea serailia - Least concern
Echinopora lamellosa - Least concern
Favia favus - Least concern
Favia pallida - Least concern
Favia speciosa - Least concern
Favia stelligera - Near threatened
Favia valenciennesi - Near threatened
Favites abdita - Near threatened
Favites halicora - Near threatened
Favites melicerum  - Near threatened
Favites pentagona - Least concern
Goniastrea pectinata - Least concern
Cycloseris cyclolites - Least concern
Merulina ampliata - Least concern
Symphyllia nobilis - Least concern
Symphyllia radians - Least concern
Galaxea astreata - Vulnerable
Galaxea fascicularis - Near threatened
Pocillopora damicornis - Least concern
Pocillopora eydouxi - Near threatened
Pocillopora madrasis - Least concern
Pocillopora verrucosa - Least concern
Goniopora nigra - Vulnerable
Goniopora planulata -Vulnerable
Goniopora stokesi - Near threatened
Porites compressa - Least concern
Porites exserta - Least concern
Porites lichen - Least concern
Porites lutea - Least concern
Porites mannarensis - Not available
Porites solida - Least concern
Pseudosiderastrea tayami - Near threatened
Psammocora contigua - Near threatened
Siderastrea savignyana - Least concern
Culicia rubeola - Not evaluated
Protection status
Biosphere reserve – Declared in 1989
Gulf of Mannar National Park (Ramanathapuram/ Tuticorin) Tamil Nadu –
Declared in 1980 – Area 6.23 – Ecosystem: 21 islands, coral reefs,
mangroves, sea grass beds and beaches.
Great Nicobar – State of Andaman and Nicobar – Year of Notification 1989 –
Area 10500.



Photo source: GOMBRT