RESOURCE INFORMATION SYSTEM - MALVAN. ICMAM-PD. CONTENTS. Programme. Development Team. Introduction. About Malvan Coast. Physico-chemical parameters. Biodiversity – An Overview. Status of biodiversity – 1998-99. Fisheries. Socio-economic status. Threats. Management Suggestions.
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About Malvan Coast
Biodiversity – An Overview
Status of biodiversity – 1998-99
Malvan is situated in Sindhudurg district, the southern most part of Maharashtra, approximately 35 km from the Mumbai- Goa National Highway No.17.
Malvan coast forms a part of the Western Ghats where Sahyadri ranges meet the Arabian sea. From Vengurla point, the coast winds towards North for about 22 km.
Malvan is an open coastal ecosystem dominated by rocky outcrops with intermittent sandy beaches extending to an area of about 6 sq. km.
Malvan coast consists of different habitats viz., rocky island, inter-tidal sandy and rocky shores, coral reefs, mangroves and estuaries.
The marine biodiversity in the region has been reported to be relatively rich and hence the Govt. of Maharashtra has declared a part of Malvan coastal waters as Marine Sanctuary in 1987.
The total area of marine sanctuary is about 29 sq. km.
The core zone covering the area of Sindhudurg Fort, Padamaged island along with submerged/exposed rocks extend to about 3 sq.km.
The Buffer Zone is approximately 25 sq. km
The North East border of the Buffer Zone is about 50 m from the sea shore near Malvan Port.
Area covering the buffer zone near “Mandal Rock” of Malvan Port.
Semi-circular sandy beach about 500 m parallel to the shore at Malvan
The buffer zone area touching the area of Malvan Rock.
The marine biodiversity in the region has been reported to be relatively rich and hence the Govt.e of Maharashtra has declared a part of Malvan coastal waters as Marine Sanctuary in 1987.
The total area of marine sanctuary is about 29 sq. km.
The Malvan coastline is marked by rocky islands, oyster rocks, rocky promontaries, sandy beaches and mud flat-mangroves (in the environs of Karli and Kolamb creek).
The Malvan coast mainly consists of granites and gneiss and laterite beds. The most striking feature of the beach is littoral concrete or beach rock which continues over long stretches. In some regions, the rocky beach occurs as a rim enclosing marshy islands.
Of the total land area (5 sq. km.), the human settlement with coconut plantation occupies 32%, upland with/without shrub 26%, forest cover 15%, mangroves 1%, mudflat 4%, agriculture land 8%, rocky islands 1% and the remaining fallow lands, irrigation tanks, water bodies, etc.
The rocky coastline of Malvan is primarily composed of sedimentary rocks, which are soft and easily eroded by both wave and wind action, providing a suitable niche for burrowing animals. Many crevices and cracks in the rock structure serve as shelters, feeding and breeding grounds for many invertebrates and act as substrata for marine algae particularly seaweeds.
The inter-tidal zone along the Malvan coast is characterised by different types of ecological habitats such as rocky islands, rocky shore, open sandy beach and mangrove forests. Coralswere found in the inter-tidal and sub-tidal regions of the rocky substratum.
In Malvan, sandy beaches are interspersed with rock formationsextending over a considerable distance into the sea and forming small bay. During low tide the exposed areas of the bay have large rocky pools with rocks partially exposed. The inter-tidal and sub-tidal areas are rich in flora and fauna.
Marine water quality monitoring is required to predict changes in the quality of a particular marine environment, so that curative or preventive measures could be taken to restore and maintain the ecological balance in the habitats. Physico-chemical parameters were studied during (1998-99) pre-monsoon and post-monsoon seasons.
Click on individual parameters.
Malvan is one of the biologically richest coastal regions in Maharashtra. Earlier reports on the marine fauna of Malvan pertain to sea anemones, molluscs, polychaetes, pearl oyster and corals. Marine fauna of the rocky, sandy and muddy shores of Malvan comprises 367 species belonging to 173 genera (97 families, 16 classes and 9 Phyla). Forty major animal groups including corals and pearl oysters, 73 species of seaweed and 18 species of mangroves were recorded during 1981.
Marine Organisms recorded from the Malvan Coast during different periods
* A.H. Parulekar, NIO, 1981, ** GIS-ICMAM, NIO, Report-2000
Totally 279 species were recorded, comprising 58 species of Phytoplankton, 36 species of Zooplankton, 83 species of Benthic organisms, 52 species of Fishes, 32 species of Seaweed and 18 species of Mangroves.
Click on individual group for overall distribution
Distribution of Phytoplankton
In the present study (1998-99) 58 species of Phytoplankton were recorded (49 species of Bacillariophyceae, 8 species of Dinophyceae and 1 Cyanophyceae). The species diversity was high during pre-monsoon season (43 species recorded) compared to post-monsoon season. The maximum diversity and density were observed during pre-monsoon, when salinity was at its peak. The density ranged from 5000 to 21,10,000 cells/l.
Distribution of Zooplankton
In the present study, 9 groups of Zooplankton were recorded. The Copepods constituted one of the most dominant taxa of Zooplankton.
Totally 34 species of Copepods comprising 24 species of Calanoida, 6 species of Cyclopoida and 4 species of Harpacticoida and 2 species of Cladocera were recorded. The maximum species diversity was observed during pre-monsoon season which could be attributed to optimal salinity (35 ppt) and high density of phytoplankton.
Distribution of Foraminifera
Totally 33 species of foraminiferans were recorded during 1998-99. The dominant species were Quinqueloculina, Triloculina, Nonion and Ammonia. The species diversity was higher in the intertidal zone (32 species) in September ’98 when compared to May ’99 (24 species).
Corals are found attached on the rocky substratum in inter-tidal and sub-tidal regions. The density was sparse, hardly exceeding 1-2 colonies per sq. m. All the colonies were of encrusting type and the height of the colonies rarely exceeded 5 cm. Only Hermotypic corals were found.
11 species of corals were recorded, viz., Coscinarea sp. Cyphastrea sp., Favites sp., Goniastrea sp., Goniopora sp., Porites lichens, Porites lutea, Pseudosiderastrea sp., Synerea sp., Tubastrea sp. and Turbinaria sp. Among them Turbinaria, Tubastrea, Porites lutea and Porites lichen were the dominant species.
At all the three locations (namely Sarjikot, Rajkot and Mouth of Kolamb Creek) where corals were found, the wave action was strong and hence at the low tide the water in the rock pools was fairly turbid. On an average suspended particulate load in the water was 120 mg/l, which is very high compared to other coral reef locations like Gulf of Mannar where a suspended sediment value of 20 mg/l was observed during 1998.
In the inter-tidal zone, salinity decreased to <15 ppt for several months in a year due to heavy river discharge which brings an enormous amount of sediment into these waters through land run off. Therefore, the occurrence of hermatypic corals in the sub-tidal zone is interesting because of their ecological adaptations to change in salinity and turbidity.
Totally 39 species of benthic organisms were recorded comprising 15 species of Polychaetes, 12 species of Gastropods, 7 species of Crustaceans, 4 species of Bivalves and one species of Stelleroidea.
Distribution of Seaweeds
The seaweeds are important as they provide shelter and act as nursery grounds for commercially important organisms. In the present observations, 32 species of seaweeds were reported, comprising 11 species of Chlorophyceae, 9 species of Phaeophyceae and 12 species of Rhodophyceae. More number of species were observed during pre-monsoon compared to post-monsoon season. The distribution of seaweeds varied with zonation. Ulva and Chaetomorpha sp. were observed at upper littoral zone, Caulerpa, Bryopsis, Hypnea, Padina, Gracilaria, Gelidiopsis were found in mid-littoral zone, and Sargassum and Gracilaria sp. in lower littoral zone. The seaweeds from sub-tidal region were dominated by Caulerpa peltata, Sargassum ilicifolium, Amphiroatragilissima, Padina tetrastomatica, Spatoglossum asperum and Stocheosporum marginatum.
In Malvan, 18 species of mangroves were recorded in Kolamb creek region. The dominant species are Avicennia sp.,Rhizophora sp., Ceriops sp., Lumnitzera sp., and Aegiceras sp.
Mangroves extend to an area of about 30 ha, out of which degraded area was about 1.5 ha in Kolamb creek.
Malvan is one of the important fishing centres on the West coast. Mackerel and oil-sardine constitute the major fishery in the West Coast of India. There are four fishing hamlets in the coastal area of Malvan, viz., – Dhuriwada, Medha, Rewatala and Wairi-dandi. There are about 175 mechanised crafts and 227 country boats, operating in the Malvan coast. The major gears being operated are trawl nets, purse seines, gill nets, dol nets and hook and line. Coastal waters of Malvan support good demersal fishery. It contributes to a sizeable portion of the demersal fish production of the Sindhudurg district. The major fish landed in Malvan comprise, elasmobranchs, clupeids, bombay duck, carangids, sardines, ribbon fish, mackerel, seer fish, pomfret, tunas, penaeid and non-penaeid shrimp, lobsters, crabs and squids.
Total fish catch during 1999-2000 was 13,433 tonnes.
Source: Assistant Director of Fisheries, Malvan-2000.
Malvan is known for its historical heritage and scenic beauty and hence has a good potential for tourism development. It is famous for the Sindhudurg Fort, standing in open sea constructed by the Maratha King Chatrapati Shivaji in the 16th century. The fort is declared as a national monument and is under the control of the Archaeological Survey of India. Several tourists visit this place every year.
There are four fishing villages along the Malvan Coast, they are Pirawadi, Sarjekot, Dhuriwada and Dhandi.
Fishermen Population - 1854
No. of active fishermen - 541
No. of fishermen houses - 375
% of literacy - 40%
No. of crafts
(i) Mechanised boats - 175
(ii) Country boats - 227
Average income of fishermen - Rs.85/day
Type of gears - Trawl net, purse seines, gill nets, dol nets and hook & line.
Other occupation – Agriculture, livestock, mining, processing plant, etc.
The entire ecosystem is unique with 281 species of flora and fauna(1998-99). Following are the major threats identified in the Malvan coast.
Intensive trawling operation around the coast.
Rampani fishing activity in core zone areas.
Over exploitation of juveniles.
Illicit felling of Mangrove trees.
Mapping of coral and mangrove distribution using remote sensing and GIS has demonstrated that these tools can be reliably used for long-term monitoring and management of Malvan coast.