The diet of telescopium telescopium and brotia binodasa as indicated by fatty acid biomarker in mangrove area of Setiu Wetland

Abstract

Fatty acid compositions in the tissues of the gastropoda Tefescopium tefescopium and Brotia binodasa collected from Setiu wetland were compared with those organic particle in sediment in order to assess the gastropoda diet. In both species, the suspended mangrove detritus was high as indicated by the mean percentage of Palmatic acid ( 16:0), Heptadecanoic acid (17:0) The contribution of this marker in the Tefescopium telescopium and Brotia binodasa are 41 % and 4 7% respectively of total fatty acid concentration. SEM (Scanning electron microscope) analysis of sediment also shows that organic matter such as pyrite framboid occur in great amount in both station. These results indicate that mangrove detritus play a significant role in the gastropoda diet. The mean concentration of diatoms markers Eicosapentaenoic acid (20:5ro3) in both gastropoda tissues ranged from 0.6744 µg g- 1 and 2.7259 µg g- 1 suggested that diatoms contribute significantly to gastropoda diet beside detritus. SEM analyses also indicate the abundant of diatoms in the sediment of the gastropoda.