|Sureerath Prawns Twenty years’ successful shrimp farming
Sureerath Farm was one of the first companies to begin shrimp farming in Thailand. From its beginnings as a small six-pond farm it has developed into an impressive company with 143 ponds and can be seen as exemplary for the whole industry. The CoC certified farm works with a closed water system and does not discharge any waste material into the surrounding ecosystem. Since its foundation, Sureerath has only produced black tigers.
Already the size of the family business is enough to impress anyone: Sureerath Farm has an area of 224 hectares. Almost exactly half of this is used for shrimp ponds, the other half for a water reservoir which is essential for the closed water system used on this farm. It includes not only the four stock water ponds and organic treatment ponds but also numerous canals in which the water pulses through the plant. None of the waste substances produced on the farm are allowed to get to the outside and pollute the environment. This is one of the principles to which Prayoon Hongrath and his wife Sureerath have been faithful since the founding of their farm in the year 1986. This does not only apply to the water on the farm – the sludge sediment is retained on the farm too. Prayoon composts it in the pond after the water has been drained off and it then serves as fertiliser for the next farming cycle.
The farm comprises 143 shrimp ponds measuring about 0.6 to 0.7 hectares. It was designed by Prayoon himself. Every grow-out pond is connected to the stock pond via a water inlet canal and so can be supplied with clean, treated water of the desired quality as required. The dirty water from the ponds flows back into the treatment ponds via effluent canals and remains in these ponds for at least seven days. During this time the organic substance particles sink to the pond bed where they are recycled by the various species of benthic fauna (benthos eaters) and mineralized. The nutrients that are dissolved in the water are absorbed by plants that grow abundantly everywhere in the treatment pond: reeds, floating flora, sedges, ferns etc.. Sureerath Prawns planted more than 3,000 mangrove plants during the past few years. Prayoon created functioning biological cycles within the farm and in this way succeeded in largely closing the system. Only evaporation losses have to be refilled from the river estuary. During the dry season water requirements can account for up to third of the farm’s water volume.
Sureerath has its own hatchery which is used twice a year to produce monodon postlarvae for stocking. 20 female spawners are sufficient to cover the farm’s requirements. As soon as they have been certified disease-free they are put into maturing tanks and fed on crushed crab and squid. For spawning, the females are put into separate spawning tanks. After 20 to 25 days the postlarvae have grown large enough to be transferred to the ponds. The ponds are stocked with PL at rates varying from 25 to 30 per square metre. Water quality, feed intake and the condition of the shrimps (colour, shell strength, general well-being etc.) are controlled at different intervals. The farm pays particular attention to feed and feeding. For one thing, because the feed is the most important cost factor and for another because feeding decisively influences health and growth of the shrimp. The feed trays are controlled three times a day to prevent overfeeding. Parallel to this, the plankton content in the water is monitored. When the feed trays are empty for three days in a row and at the same time the plankton content in the water decreases the feed quantity can be increased by 10%. After two months in the pond the growth of the shrimp is measured at intervals of 10 days. This complicated feed management system enables Sureerath Farm to avoid unnecessary feed losses and achieves good feed conversion rates (FCR) of between 1.2 and 1.7. “Our aim is to produce tiger prawns in counts of 30 to 40 per kilogram” says Prayoon Hongrath. “Flavour and texture are optimal when the shrimps weigh 30 g.”
Depending on the growth rate the crops can be harvested after 120 to 150 days. To do this a pump system is installed in the pond and the water pumped off into the effluent canal. A tight meshed net funnel is placed in front of the suction opening of the pump system to hold back the shrimp. Every pond produces an average of between 3 and 5 tonnes per crop. The total production from Sureerath Farm is about 800 tonnes per year.
Sureerath Prawns is undoubtedly an exemplary farm in the Thai shrimp industry. The management of the family business is worthy of imitation, too. Order and cleanliness prevail throughout the farm. Prayoon Hongrath’s knowledge of shrimp farming is rated highly in the industry. Students are eager to gain practical experience in his company. On the farm site there is even a building which serves as accommodation for trainees. And the future of the family business seems to be safe, too: Prayoon’s two sons, Kritsada and Virath and their daughter Duangkamol have been helping their parents run the farm since completing their training.
EURO FISH Magazine: March 2/2006