Eucheumatoid cultivation continues to expand with a variety of methods that can increase production. However, new cultivation approaches are rarely reported. This study examines new methods of seaweed cultivation in floating cages/nets including: horizontal net, vertical net, basket net and longnet. The research was conducted from March to November 2019 in the coastal waters of Baubau, one of the prime seaweed cultivation areas in Southeast Sulawesi Province, Indonesia. The growth rate of Kappaphycus alvarezii in these floating cage variants was assessed, and compared with the traditional longline approach. Propagule wet weight was measured daily to document growth rates. The results show that K. alvarezii grew faster with better thallus morphology in the floating cages than using longline cultivation. Daily production and specific growth rates (SGR) of K. alvarezii were higher for cultivation in the floating cages than on longlines. Moreover, cultivation in floating cages not only improved growth rate but also protected the seaweed from attack (grazing) by herbivores, especially herbivorous fish such as siganids.

Nelson Vadassery

Passionate about farming the oceans for large volumes of seaweed.