Government worker’s research helps ‘ulang’ industry in CL
City of San Fernando— Government worker Willy Cruz could have potentially earned significant profits if he had patented the results of his research; however, he made a deliberate choice to allow free access to his developed larval hatchery protocols, which are essential procedures for successfully rearing freshwater shrimp larvae, to the public.
This decision has contributed to the establishment of the country’s leading ulang industry, particularly centered in Pampanga and the broader region of Central Luzon. Now serving as the Regional Director of the Bureau of Fisheries and Aquatic Resources (BFAR), Cruz reflects on the substantial impact of his rearing protocols for giant freshwater prawns.
His journey began in 2000 when he initiated the development of protocols tailored to local strains of giant freshwater prawns. This research, titled “Larval Rearing for the Hatchery Production of Local Giant Freshwater Prawns,” was conducted during his tenure as the production station head at the BFAR station in Castillejos, Zambales.
As the BFAR began efforts towards commercial ulang production, Cruz completed his study in 2004 and implemented ulang production in hatcheries in Zambales. The hatchery pond design used was also crafted by Cruz himself.
Despite encouragement to apply for intellectual property rights registration, Cruz opted to share his research openly.
Why Ulang?
Giant freshwater prawn (Macrobrachium rosenbergii), known locally as ulang, is a cherished delicacy in Central Luzon. Kapampangans value ulang for its rich taste, derived largely from the fat stored in its large head. In Pampanga, it is affectionately referred to as buntukin and is primarily cultivated in Candaba.
Ulang farms in Candaba are also sources of breeders for hatchery production. Ulang holds a prominent place in local cuisine, finding its way into both household kitchens and restaurants.
According to Cruz, ulang commands a high market value, fetching between P400 to P600 per kilogram inland.
Larval Rearing for Hatcheries
Rearing ulang in hatcheries requires careful consideration. Cruz developed a larval rearing protocol specifically tailored for local giant prawns. Before the establishment of government and commercial hatcheries, juvenile ulang were typically sourced from local rivers and raised in ponds, or occasionally imported.
The research initially drew inspiration from shrimp rearing practices, given their shared larval stage. However, Cruz discovered significant differences between shrimp and ulang. Notably, ulang’s feeding protocols are simpler.
The hatchery protocols involve a 30 to 45-day process to produce post-larvae (PL) using a precise hatching solution. Ulang, being a catadromous species, requires brackish water, typically a 12 ppt (parts per thousand) salt solution for larval rearing.
Feeding involves a combination of artemia and egg custard. “Thailand had already achieved success with their local strain. Our protocols were developed specifically for our local strain,” Cruz explained, emphasizing that these protocols significantly improved larval survivability, ranging from 40 to 90 percent.
Cruz’s protocols emphasize meticulous pond preparation, stringent water quality monitoring, and precise feeding practices. Post-larvae released into ponds can achieve survival rates of up to 80 percent, according to Cruz.
The initial success of hatchery production spurred the establishment of more hatcheries in Central Luzon, ensuring stable communal stocks for local ulang farmers and commercial ponds.
Central Luzon leads the Philippines in ulang production, a high-value industry yielding substantial profits. In the first quarter of 2023, ulang production reached 120 metric tons, contributing 2.7 percent to the total volume of inland fisheries production, as reported by the Philippine Statistics Authority.
Cruz noted that hatchery production is particularly active in Aurora and Bulacan, while Pampanga excels in mature ulang production. He highlighted Pampanga breeders’ unique method of combining hatchery stocks with juvenile ulangs from local rivers, fattening them for commercial sale.
“Most farmers practice polyculture, raising ulang alongside tilapia,” Cruz remarked. “At one month old, tilapia can coexist with ulang, with feeding focused more on tilapia. While ulang supports tilapia production, it remains a high-value commodity,” Cruz added, emphasizing that mixed culture can maximize production for farmers.
To ensure sustainable ulang production, a minimum pond size of 500 square meters per hectare is recommended. A 500 square meter pond can generate revenues of P20,000 per cycle. Ulang requires four months to mature, allowing farmers to conduct two cycles per year.
Expansion of Hatcheries
Cruz highlighted that Central Luzon is highly active in hatchery production which prompted the DFAR to initiate hatchery expansions. BFAR facilities in Aurora, Castillejos, Masinloc, and Bulacan are key contributors to ulang production for local farmers. According to Cruz, there are plans to expand production facilities in Aurora and Zambales.
Despite Central Luzon being the primary producer of ulang in the country, current production levels are insufficient to meet local demand, with annual catches primarily allocated for local consumption. Hatcheries also play a crucial role in bolstering river stocks. In 2023, BFAR released approximately 3,000 ulang into the Guagua-Pasak River in Guagua town, marking a significant effort to enhance local river populations.