Seaweed (Mwani) Farming as an Adaptation Strategy to Impacts of Climate Change and Variability in Zanzibar

Abstract

This study aimed at identifying climatic factors affecting seaweed (Mwani) farming, its associated impacts and adaptation strategies employed by seaweed farmers to cope with the impacts of climate variability and change along the coast of Unguja Island. The study was carried out in four coastal villages of the Island. The villages were chosen because a majority of communities were engaged in the production of Mwani. Household surveys were conducted to collect quantitative data, whereas FGDs and observation were employed to collect qualitative information. A total of 476 households engaged in seaweed farming were used as a sampling frame in the study, where 25% of them (119 households) were randomly selected to participate in the interviews. Results reveal that Mwani production has been widely practised by women (92.4%) and mostly by married people (87.2%). The labour force for seaweed farming fell within the age group 31–49 years (60.3%). About 77.6% and 70% of the respondents were specific Mwani producers and literate, respectively. Despite the challenges Mwani production was the most popular alternative livelihood performed by many rural populations in Zanzibar. Seaweed farmers perceived that seaweed growing in Unguja had been affected by changes in climate factors and non-climatic stressors over the last 20 years. Climatic variables that have affected seaweed included increasing surface water temperatures, wind speed, sea waves, irregular rainfall patterns and salinity. Mwani production had generally declined over the last 5 years. Despite a number of strategies taken by Mwani growers to cope and adapt to the impact of changing climate, new research is needed to develop new adaptation technologies that will help farmers to counteract the effect of desiccation and associated diseases aggravated by climatic variables in the field.