Chennai, Jun 29 (IANS): Several state governments are showing interest in mud crab farming and are signing up agreements with the Rajiv Gandhi Centre for Aquaculture (RGCA), said a senior official.

The official said the RGCA part of the Marine Products Export Development Authority (MPEDA) is the only mud crab hatchery to get a patent for its technology.

The official also said that mud crab farming can be done at several defunct shrimp hatcheries.

"We have patented the technology which ensures higher egg-to-crab survival rate. The egg-to-crab survival rate of our standardised technology is about 7.5 per cent to 17 per cent. The global average is only about 3 per cent," said S. Kandan, Project Director, RGCA.

He said the state governments of Maharashtra, Kerala and Andhra Pradesh have signed agreements with the RGCA to train their farmers in mud crab farming.

"A fully-grown eight-month-old mud crab can weigh between 600 gm and 1 kg. The per kg rate of crab is about Rs 1,100," Kandan added.

According to Kandan, the patent for the technology was filed way back in 2011 and after a lot of clarifications, the patent was granted recently this year.

Kandan said an entrepreneur may need about two acres of land near the sea front and the total investment will be about Rs 3 crore to have a farm of 1.4 million to 3 million capacity.

The RGCA will provide the training and also the seed stock.

"Mud crab is a potential candidate species for commercial-level aquaculture. We are promoting it as a targeted fishery with high price value. We are also providing crab-instars (baby crab) to the farmers at an affordable cost, which includes only the production cost," said K.S. Srinivas, Chairman, MPEDA, and President, RGCA.

"Significantly, it has huge potential to diversify the brackish water aquaculture as mud crab farming is the best option in defunct shrimp farms," Srinivas added.

Kandan said Tamil Nadu is the hub of live mud crab export, mainly to Southeast Asian countries like Singapore and Malaysia besides the Middle East, while crab meat is a delicacy in the US and Europe. From the Chennai port alone, around two tonnes of live mud crab are exported every day.

RGCA, which is MPEDA's Aquaculture Technology Incubation Centre headquartered at Mayiladuthurai in Tamil Nadu, is currently producing 1.4 million seeds of mud crab per annum.

According to RGCA, crab, as the alternative species for shrimp, has very good export value and also compares favourably with it in terms of value addition.

The mud crab commands the highest price when it is exported as whole in live condition or as crab meat in chilled condition. In case of shrimps, the value increases on the basis of the value addition process it undergoes.

Mud crab fetches high value on exports with minimum investment whereas shrimps require high-end value addition to fetch higher value, officials said.