- NPV at 15% DF : Rs 43434
- BCR at 15% DF : 1.51 : 1
- IRR : 169 %
9. Marketing
There is only limited demand for the mussel meat due to lack of awareness among the consumers . However , there is scope for its export to Southeast Asian countries. A marketing tie-up with the processing plants will be useful for marketing of the product.
10. Interest rate for ultimate borrowers Banks are free to decide the rate of interest within the overall RBI guidelines. However, for working out the financial viability and bankability of the model project we have assumed the rate of interest as 12% per annum.
11. Interest rate for refinance from NABARD
As per the circulars of NABARD issued from time to time..
12. Repayment period
The loan amount of Rs 39,500/- can be repaid in five years starting from first year onwards as the culture period is for 6 months and it is possible to take the first crop during the first year itself.
13. Security
Banks may take a decision as per RBI guidelines.
ANNEXURE - I
Farming Technology of Green Mussel
1. Biology
The scientific name of the green mussel is Perna viridis. The mussel has organ systems similar to those found in oysters with some modifications. It has a foot as in clams though smaller in size, providing limited mobility. A mussel can discard the byssal strands and secrete new ones for enabling it to change position. Phytoplanktons forms the food of the mussels, and they are filter feeders. P.viridis in the natural conditions grow to 63 mm in 6 months to 133 mm in 4 years. However , the growth in culture operations have been more than in the natural conditions. In mussel the sexes are separate and the gonads which are located in the body proliferate in to mantle. The male gonad is creamy white in colour while in the female it is pink or reddish. The mussel attains first maturity at 15.5 to 28 mm size.
2. Technology of mussel culture
A) Seed collection / Availability
The spawning season of the green mussel is between July and September and the spats are found carpeting the inter tidal and submerged rocks. At present they are collected manually and during the peak season an individual would be able to collect 10-12 kg of seed in one hour. The seeds can also be collected using spat collectors such as roof tiles, coir ropes and nylon ropes. Even though the hatchery technique for commercial mussel spat production has been perfected by Central Marine Fisheries Research Institute , Cochi, there is no commercial hatchery at present in India. As such the culture operations have to depend on the availability of natural seed .
B) Farming models
Three types of farming are practiced for culture of the mussels as follows:
i. Sea Farming - Longline culture of mussel is practised in shallow waters of 10 - 15 m depth . This method of culture can withstand the severe monsoon conditions in the west coast. The longline unit consist of 60 mt long horizontal HPD rope of 20-24 mm thickness anchored at both the ends with 150 Kg concrete blocks and a series of 100 liters capacity barrels as floats fixed at 3 m intervals. Vertical lines of 6 m length seeded with mussel spats are hung at a distance of 75 cm between two floats in the main line. A longline unit of 60x60 mt can accommodate 12 horizontal ropes and 920 - 1000 vertical ropes. The distance between two horizontal lines is 5 mt . At every 20 mt the horizontal lines are connected using additional horizontal lines.
ii) Estuarine farming - Pole culture and stake culture are done in estuaries at a depth of 1.5 to 3 m. The spats of 15 to 25 mm are wrapped around the poles or stakes with cotton mosquito nettings. The spats gets attached to the poles in three or four days and by this time the cotton netting will disintegrate. Periodical thinning is necessary.
iii) Rope culture - Rope culture of mussel is widely adopted in Northern Kerala. Ropes are suspended from rack made of casuarina and bamboo poles. The average area of rack is 400 sq m and length of the ropes used for seeding ranges from 1-1.25 mt depending on the depth of the water column. Poly propylene ropes wound with coir ropes are used for seeding. These ropes are hung down from the racks at an interval of 1 feet and nearly 500 - 550 ropes could be suspended from one rack. The seeds collected from wild are being sold in units of one bag and one bag of seed can be used to seed 8-10 ropes. The normal size of the seed ranges from 35-65 mm. Seed collected has to be seeded on the same day and it is estimated that one person can seed around 60-70 ropes in a day. The culture period in Northern Kerala where the activity is taken up fairly on a large scale starts from November and ends in the middle of May before the rains. Once in a fortnight the ropes are lifted for monitoring the growth and removal of fowling organisms . The mussel grows to 80-100 mm size with in 6 months of culture period and it is estimated that around 2 lakhs mussels can be harvested from 400 sq mtrs.
3. Harvesting of Mussels
The mussels are harvested after attaining a size of 80-100 mm with in a period of six months. Indication of good mussel could be measured by the condition index which is the ratio of wet meat weight to the total weight of the mussel. The condition index shows seasonal changes and is usually related to reproductive cycle. It is generally high before spawning. The wet meat normally forms 33 to 40% of the total weight in mussel as found in different experiments.
4. Processing
Before removing the meat from the mussel it is necessary to carry out depuration which is a process in which the mussels are kept for 18 hours in clean sea water which will purify the mussels of bacterial pollution. The mussels can be processed in different forms like frozen, canned, smoked, dried and marinated. The mussel shell is used as a liming agent in coconut plantations. The mussel shell gives good quality lime which finds application in many industries.
Annexure - II
Estimated financial outlay for culture of Green mussel P.viridis in 400 sq m area Rack culture unit
A. Capital Cost |
