Mangrove-associated mollusc research at SEAFDEC/AQD.

Abstract

Mollusc research at the Aquaculture Department of the Southeast Asian Fisheries Development Center started in 1975 and focused on two commercially important mangrove-associated bivalves, the slipper-shaped oyster (Crassostrea iredalei) and the green mussel (Perna viridis). Studies conducted were on spatfall forecasting to increase collection of seeds from the wild; improvement of farming techniques; seed production in the hatchery; bivalve sanitation; and transplantation. These studies have led to the development of a suitable spat collector for oyster and mussel; promotion of the raft culture method for oysters and mussels to prevent siltation of growing areas, including a low-cost raft design for this purpose; refinement of transplantation techniques to increase production and to grow osyters and mussel in suitable areas without natural populations; and desgin of a prototype low-cost depuration unit. A socio-economic study of oyster and mussel farming practices in Western Visayas provided information on current farming practices and profitability. A study done on the use of green mussel as biofilter in a semi-intensive shrimp pond showed that shrimp stocked with mussels grew faster than those without. A study on the biology and fishery of the "imbao" Anodontia edentula, another mangrove-associated bivalve, is ongoing. Spawning has been achieved in the laboratory and larval stages monitored were first polar body, 2-cell stage, morula, ciliated gastrula, trocophore, veliger, and pediveliger.