The giant freshwater prawn (Macrobrachium rosenbergii) is the largest of its kind and is naturally found in Philippine rivers. Freshwater prawns differ from shrimps with their long claws that are up to twice their body length and a taste very much likened to lobster and tiger shrimp.
Dr. Frolan Aya, a scientist at the Southeast Asian Fisheries Development Center (SEAFDEC), said that this prawn “is a promising alternative to tiger shrimp due to its high market value, high export potential and low susceptibility to diseases.”Although not nearly as valuable as tiger shrimp, freshwater prawns currently do not face the same risks of diseases as their distant crustacean cousin due to lower density culture practices. Unlike tiger shrimp, which requires regular screening for diseases and facilities to keep out viruses and bacteria, freshwater prawns in extensive culture are mostly content with proper nutrition and good water quality. However, prawns are carriers of shrimp viral diseases as well, and thus farmers should still be careful not to pass on viruses to nearby shrimp farms.
Farmers can use simple ponds, cages, or even rice fields. “Cage culture is suited for marginalized fish farmers who have no land to develop into ponds and requires minimal start-up investment,” shared Dr. Maria Lourdes Aralar, a SEAFDEC retired scientist who largely developed the technology for lake-based cage culture. The simplicity of freshwater prawn farming means it is widely farmed across Southeast Asia such as in Vietnam which produced 547,000 tons in 2014 and Thailand coming in at a far second at 17,000 tons. However, Philippine farm production in 2014 was only 9 tons. Although, 1,700 tons were sourced from the wild.
Need for more hatcheries
The bottleneck in Philippine production is not the number of prawn-growing ponds and cages, but the production of postlarvae. “The production is very limited for a lack of sufficient quantity of postlarvae for grow-out, but there is potential for the aquaculture industry,” said Aya.
Training for those interested in the hatchery and grow-out of giant freshwater prawn is regularly offered by SEAFDEC at its Binangonan Freshwater Station in Rizal. The station also produces postlarvae from its research activities that are made available to prawn farmers.
Currently, other sources of postlarvae are the Bureau of Fisheries and Aquatic Resources (BFAR) National Freshwater Fisheries Technology Center in Nueva Ecija and National Integrated Fisheries Development Center in Pangasinan. Dan Baliao, chief of SEAFDEC Aquaculture Department (AQD), also revealed that they recently developed an initial prawn hatchery facility in Tigbauan, Iloilo currently with about 3,000 broodstock. “We are just starting, but once construction of our bigger Macrobrachium rosenbergii hatchery is finished, our goal is the mass production of postlarvae at Tigbauan for farmers and to again jumpstart the giant freshwater prawn industry,” Baliao said.
Photo source: SEAFDEC. Photos by IT Tendencia.