Challenges of seaweed farming
Integration of seaweeds into marine aquaculture farms in the WIO is, nonetheless, not without its challenges (37). Despite of its benefits in economic, environment and health benefits, seaweeds aquaculture faces several obstacles that hinder its successful intergration in WIO. According to Msuya et al. (2014) (38) some potential species were unable to survive due to the problem of epiphytes coupled with ice-ice diseases in WIO region. Among the affected seaweed species was Kappaphycuswhich is preferred in the foreign markets for its thicker gel, kappa carrageenan as compared to weaker iota carrageenan from Eucheumaspecies (38). Moreover, Tobisson (2013) (39) reported low involvement of men in seaweed farming, this is caused by the little gain from seaweed farming process as compared to labour involved. Though there is high demand for seaweed products in the international market, the price paid to farmers is very low as compare to labour seaweed farming takes (39). Therefore, for the sustainability of seaweed farming, funders need to consider ways to improve the efficiency of seaweeds farming including value addition for more income generation and increase pay for farmers.
Apart from financial issues, reports of women involved in seaweed farming have health problems such as back pain and eye-related problem due to tedious work performed in the seaweed farming process; headache; allergies; injuries fatigue and respiratory problems are available (40). This may be contributed by lack of knowledge which leads to farmers participation without using protective equipment leading to contamination from toxic chemical compounds from seaweed, epiphytic bacteria or harmful algal bloom and absorbed heavy metals from seawater as a result of long-term exposure (41). It is important for responsible authorities and funders to incorporate seminars to all farmers and educate them about the need for protection for safety. Also, conflicts are arising among seaweed farmers and other users such as the tourism industry. In such a way that seaweed farming is prohibited in areas with more upmarket materials; accommodation on the north and south coast island and outside some hotels on the pretext that was visually unattractive (42). This may be caused by inadequate knowledge on coexistence between tourism and seaweed farming by putting clear boundaries and roads within the marine sites.
According to De la Torre-Castro and Lindström (2010) the process of uprooting the seagrass in preparation of seaweed farm contributes to the decreased fish population and coastal erosion (43). This is a challenge which needs vigilant supervision. On the other hand, apart from decades of its existence in WIO, seaweed farming suffers the use of inappropriate or outdated technology. Most commonly traditional off-bottom methods, using wooden stakes (pegs) planted in the sand and ropes to which seaweed bunches are attached (44). However, this technology is leading to low yield as it is labor-intensive and is utilized in a shallow area where environmental variables change rapidly and spoil productivity. Seaweed farming at low depth is more susceptible to changes in sea surface temperature and salinity, especially during the rainy season, resulting in disease outbreaks such as epiphyte infestation, which suppresses growth; discoloration of the seaweed thali that affects the quality and cause ice-ice (45). Indicating the need for seaweed farmers, funding, and responsible authorities to find the means to facilitate farmers to have modern farming equipment’s to increase productivity and hence income. Moreover, the nature of technology renders it especially sensitive to currents and storms, resulting in tangled ropes, broken and lost products. In this case, maintenances of the seaweed plots becomes physically hard and dangerous; requiring daily attention and strain to farmers who are mainly women with low pay (45). In addition, climate variation impacts the high profitable species in WIO region, for example Eucheuma cottonii with higher price because of its higher carrageenan content cannot thrive in shallow waters, as a result, farmers opt to cultivate E.spinosum (45).
Apart from the challenges facing seaweed farmers in the WIO, there is the need to investigate possibility to grow other native seaweeds species, increase value addition to farmed species and use of modern technologies for sustainability of ecosystem. Also, there is a need for establishing product acceptability so as in the near future can be accepted as food; creation of sustainable market and balance demand in the local and international forum. Also, the need for utilization of both economic value of the seaweeds produced and ecosystem services offered by marine farming activities.