PENEMPELAN KERANG Septifer bilocularis PADA SUBSTRAT DALAM AGREGASI KERANG DI DAERAH PASANG SURUT PESISIR TIWOHO

Abstract

Research of mussel attachment, Septiver billocularis was carried out on the intertidal zone of coastal Tiwoho, north Sulawesi. The objectives of this study were 1) to identify type of substrates (organic and inorganic) to be attached by box mussel Septifer bilocularis, 2) to identify substrate preferences of Septifer bilocularissettlement. 3) to know the favorite position of settlement in mussel aggregation. The PVC plate has 16 holes, each with diameter of 1.8 cm, which had been filled randomly with organic substrate of coconut fibers and palm fibers, and mussel shell with byssus threads, then inorganic with plastic rope. Each substrate had 4 replicates.  The PVC plate, four replications, each was placed at edge and middle of large aggregation, the PVC plate with substrates was also placed in isolated aggregation.   All PVC plates were placed in intertidal Tiwoho for 1.5 months.  The settlement data were analyzed using a Two-Way ANOVA with substrata and position in patch as the main factor. Before running the test, data were transformed using arcsin.  The results showed that the settlement of box mussel (< 1 mm) attached to organic substrata such as coconut and palm fibers, as well as inorganic substrates, plastic rope.  Settlement of box mussels on shells with byssus threads had sizes ranging from > 1 mm to - < 3 mm. A Two-way ANOVA test shows that settlement was not affected by substrata (P > 0.05), the settlement of box mussel was affected by position in aggregation (P < 0.05).  Factors such as the effect of physical, chemical, and biological on box mussel settlement are discussed.

Keywords: Aggregation, Attachment, Shellfish, Substrate, Tiwoho Coast