Bivalve resources and its exploitation in Malabar

The Malabar region of Kerala (Kozhikode, Kannur, Mahe, Kasargod) has significant bivalve resources contributing to subsistence fisheries of the local population. Clams and oysters form the major resources in the estuaries and backwaters. The clams, Meretrix casta, Meretrix meretrix, Villorita cyprinoides, Paphia malabarica and the edible oyster, Crassostrea madrasensis form the major exploited bivalve resources of commercial significance

Biology of Mactra violacea (Gmelin 1791) from Kerala, south-west coast of India

The surf clam Mactra violacea (commonly known as violet trough shell), is distributed all along the sandy beaches of north Kerala. It occurs in the surf zone, upto 75-100 m depth. It is a large clam (upto 80 mm) with high meat content and nutritive value which is collected and consumed by the local people. The biology of the surf clam was studied to understand its growth, edibility and potential for mariculture

Site selection for Mussel Culture

In India, most of the bivalves produced are fished from the natural stocks. At present green mussels are cultivated mainly in the states of Kerala and Karnataka., Production o f bivalves by mariciilture in India is very little compared to the rest o f the world. The major source for collection o f the seeds of the bivalves is through wild collection or through laying of clutch material as in edible oysters

Growth and production of vertically and horizontally suspended mussel ropes in estuarine culture

An experiment to compare the growth and production of vertically and horizontally suspended mussel ropes was conducted in the CMFRI Demonstration cum Research Farm in Chaliyar Estuary, Karuvanthiruthy, Kozhikode. Approximately 13.5 m of vertically suspended and 24 m of horizontal ropes were set in the farm in January 2005. The growth in terms of length and weight was monitored at monthly intervals. A total harvest of 587.7 kg shell-on mussels were obtained of which 249 kg was from vertical and 339 kg from horizontally suspended ropes

Mussel seed prospecting along Malabar coast and the influence of rainfall

The green mussel Perna viridis forms a significant fishery along the Malabar coast. The green mussel forms extensive beds on the laterite and granite formations along Kasargod to Kozhikode in the intertidal and subtidal zones up to 15-20m depth.The mussel farming sector now faces twofold problem in acquiring seed for farming in the estuaries. a) Mussel spat settlement has been relatively poor and not available duringthe mussel farming season. b) The mussel pickers are unwilling to supply seed to the mussel farmers

Bivalve resources of Moorad Estuary, north Kerala

A bivalve resource survey of Moorad estuary in Badagara District of north Kerala was carried out during February 2004 to assess the bivalve species, their distribution and potential stock. Sampling sites were fixed within five main zones of the Moorad estuary based on the clam fishery activities and local enquiries. The bivalve distribution in a unit area was taken by demarking the area of clam bed with a quadrant. Observations on the area of clam bed, water clarity, depth and temperature were recorded at each site. Surface and bottom water samples were collected and hydrographic parameters like salinity, temperature, pH and dissolved oxygen content, productivity, nitrate, phosphate and silicate were recorded. Sediment samples were collected to analyse the grain size and organic content of the clam beds. All samples were analysed within 24 h except sediment samples. Average density of bivalve per square metre area was analysed and the potential stock was estimated for each bivalve species in the estuary

Fishery and biology of Meretrix casta (Chemnitz) in the Moorad estuary, Kerala

Meretrix casta forms an important fishery in the Moorad estuary. The average annual landing for the period 2000-2004 was 426t, the average catch per effort was 573 kg and total effort was 3182. Clams ranging from 28 to 32 mm size contributed to the fishery. M casta is a continuous breeder with two peaks in March-April and August-September. The precentage edibility ranged between 8 and 16. The standing stock biomass in the Moorad estuary was estimated at 2073 t with an average density of 1096 numbers per sq. m. The present status and management options for this important fishery are discussed

Mussel farming initiatives in north Kerala, India: a case of successful adoption of technology, leading to rural livelihood transformation

The Malabar region, extending from Malappuram to Kasargode districts of Northern Kerala, is a well-known mussel fi shery zone of India. Over 7,000 t (80%) of the total green mussel (Perna viridis) catch is exploited annually from this zone. The Central Marine Fisheries Research Institute (CMFRI) developed techniques for mussel culture in 1971 and subsequently fi eld demonstrations in different areas with direct involvement of local rural folk were carried out1. Demonstrations to popularise this technology have led to adoption of this simple farming method particularly in the Malabar region2. The Malabar coast has extensive backwaters and estuaries, which are suitable for mussel farming during the post monsoon months (November to May) when higher saline conditions prevail. Farming activity during this period provides an opportunity for supplementary livelihood and additional income to the coastal rural population

Mussel culture in backwaters of Kasaragod district, Kerala

Mussel culture is increasingly getting Popular in Padanna and Cheruvattur Panchayats In Hosdurg Taluk of Kasaragod district in Kerala, By virtue of the popularisation efforts made by the CMFR Institute. Initially this low cost technology Of farming was transferred to five groups with 15 To 21 farmers at Cheruvattur and Vallyaparamba, Mostly women groups

Length-weight relationships of Meretrix casta in estuaries of north Kerala

The yellow clam Meretrix casta (Chemnitz, 1782) forms significant sustenance level fisheries as it is used for local consumption as well as for the lime industry. Length– weight relationships of M. casta from Chaliyar, Moorad estuaries (Kozhikode district), Kavvai estuary (Kasaragod district) and Mahe estuary, Mahe are reported as they are important inputs in fisheries management decisions