Long Line Seaweed Farming as an Alternative to other Commonly used Methods in Kenyan Coast

Abstract

To counter the rampant fishing pressure on the over exploited fisheries resources, seaweed farming is gaining momentum as an alternative livelihood among the Kenya coastal communities. There is also a worldwide growing interest in the use of seaweed in food and chemical industries, not forgetting its contribution to the blue economy. In this regard, various methods of seaweed farming like raft method and off bottom method have been used but production is still low. This study aimed at assessing the growth rate and yield of Kappaphycus alverazzii (cotonni) and Eucheuma denticulatum (spinossum) using the long line floating method. The experiment was performed on 3 plots per species of seaweed with a plant stocking density of 36 seedlings per plot. Measurements of production were done fortnightly. The highest production was realized with E. denticulatum during the North East Monsoon (NEM) period (1321.47±93.3 g) with a Daily Growth Rate (DGR) of 6.59% and a yield of 19.9 tonnes/ha. During the South East Moonson (SEM) a weak yield relationship was manifested. K. alvarezzii showed a production of 826.27±20g during NEM with a DGR of 5.96% and yield of 14.95 tonnes/ha. During SEM poor daily growth rate of 1.47% and yield of 1.892 tonnes/ha was realized. Based on highest daily growth rate and yield, culture of E. denticulutum during the NEM season was optimal