Seaweed (Gracilaria) Farming Trials in Sorsogon, The Philippines

The paper is on experimental farming trials carried out in Sorsogon Bay and the eastern coastal areas of Sorsogon, the Philippines, using Gracilaria species found in the area. Four major Gracilaria species - G. firma (=G. fisheri), G. fastigiata, G. cylindrica (=G. changii) and G. tenuistipitata - were recognised and used in the trials. Fixed bottom monoline (10 × 10 meter plot), floating raft monoline (5 × 5 meter) and pond (in brackish water fish pond) farming trials at 18 localities in the area were conducted. Three environmental conditions were identified : high salinity/ clear water/ firm substrate; high salinity/ semi-clear water/ sandy-mud substrate; and low salinity/ semi-clear water/ muddy substrate. Under optimum environmental condition during early part of year, an average daily percentage growth rate for G. fastigiata, G. firma, G. cylindrica and G. tenuistipitatawas observed to be 9.0%, 8.7%, 9.1% and 11.2% respectively from monoline farming trials. For G. fastigiata and G. firma, an average weight attained after 54 days of growing period with initial average individual seed plant of 35.3 grams and 51.0 grams were recorded as 505.2 grams and 1,005.8 grams respectively from fixed bottom monoline farming trials.