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New Fish Cage Operations Technique in Proposed in Magat

11 April 2013

PHILIPPINES - The Bureau of Fisheries and Aquatic Resources Region 2 (BFAR-2) is proposing a new technique in fish cage operations based on the result of the harvest field day demo and research project at the Magat Reservoir.

Information Officer Max Prudencio said that the demo and research project, which showcased the viability of fish cages in the Magat Aquapark, aims is to revitalise the once-vibrant aquaculture industry in said area.

Mr Prudencio said that the aquaculture park, which is a joint undertaking between BFAR -2, SN Aboitiz Power, NIA – MARIIS, PLGU Isabela, and LGU Ramon, consists of six modules fish cages, with mooring system, service boats, fingerlings and caretakers hut.

“The fish cages and equipment were provided by BFAR while feed inputs totaling to 270 bags were shouldered by the SN Aboitiz Power Corporation. Harvested after four-month culture period was the demo and research module operated by the Bureau. Each cage was stocked at different densities and fed at varying rates,” Mr Prudencio explained.

As per result of the demo, the cage (Cage D) stocked at 10 pieces per cubic meter and fed at rate of eight per cent body weight down to two per cent for a total of 10 bags feeds per thousand pieces, emerged best with harvestable stocks averaging 200 grams each in terms of growth performance.

However, the cage (Cage C) with same number of stocks but fed daily at a reduced ration of six bags per thousand, is not far behind with end weight averaging 155 grams apiece. In as much as there were no observed heavy mortality on both cages, survival rate is assumed at the standard 85 per cent.

“As per estimate, we can have 95 kilograms more harvest in Cage D compared to Cage C, however, this difference, if sold at P83.00 farm gate price, can almost be offset by our savings of 10 bags feeds amounting to P 7,200.00 on Cage C. This is assuming that both size of harvest can have a similar price in the market,” said Alexander Castañeda, a BFAR-2 aquaculture expert.

“This shows us that the management strategy adopted in Cage C can also be profitable although with lesser production expense,” Mr Castaneda added

Other treatments that were tested were no feeding and alternated day feeding but results for both were not encouraging. Mr Castañeda, however said that they still need to undertake more runs to ascertain results of the study.

From a height of 5 metric tons average daily production in 2003, fish produced in Magat is now down to 0.8 metric ton due to successive losses incurred by operators due to man-made and natural causes. The huge reduction is a result of huge losses incurred by previous operators which were attributed to both man-made and natural causes.

The aquapark project, a brainchild of BFAR Director Asis G. Perez, ensures that fish cage zoning based on hydrobiological survey, best cage management practices, and proper sanitation will be followed by prospective locators in order to avoid the pitfalls made in the past.

Meanwhile, BFAR-2 Regional Director Dr Jovita Ayson revealed that the bureau is set to award 10 more fish cage modules in order to benefit more fisherfolk associations. Feeds however, will again be requested from SN Aboitiz Power.

The Magat Dam and Reservoir is bordered by the provinces of Isabela, Ifugao and Nueva Vizcaya. It serves as source of irrigation for most of Isabela and neighboring provinces as well as for hydroelectric power generation.

TheFishSite News Desk

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