Recruitment of Eucheuma and Kappaphycus on a farm in Tawi-Tawi,Philippines

Vegetative regeneration is the only farming method for Eucheuma and Kappaphycus, the world's most important carrageenophytes. Lack of seedstock has been a problem following natural calamities, overharvesting, grazing and outbreak of "ice-ice" disease. Hence, studies to help develop an alternative method of generating Eucheuma and Kappaphycus sporelings on a seaweed farm in Tawi-Tawi, Philippines were carried out from May 1993 to July 1994. Mactan stone blocks were deployed in two positions at two sites in Tawi-Tawi, one of the biggest farming areas in the Philippines. Recruits were first observed five months after deployment. Nested ANOVA was used to investigate the effect of current speed (C), water movement (M), number of days with minus tide (D), salinity (S), temperature (T), area of deployment (A) and position of blocks (P) on the recruitment of sporelings (R). Since C, M, D, S, and T were always on the same mean level within an area, the effects of these variables were assumed by the effect of area and thus, the A and P variables were the ones fitted in the ANOVA model. Repeated measures ANOVA showed no significant difference in the effects of A and P on visible R from May to November 1993 and March to July 1994. The Helmert transformation showed that mean recruitment of Eucheuma and Kappaphycus between May 1993 and subsequent time points was significantly different. This was also true for recruitment in September 1993, December 1993, January 1994 and February 1994, which were highly significantly different compared to the means of subsequent time points. Multiple regression analysis showed that C, D, and S had significant effects on recruitment of Eucheuma and Kappaphycus in both areas while effect of T was significant only in area I.