**8. HAB mitigation strategies**

HABs are the major threats to public health and the economy in benthic areas. HAB formation is not only responsible for destroying aquaculture industries but also severely affecting the tourism industries. Besides fish poisoning, HAB affected beaches become vulnerable due to fouling of water, which may cause skin diseases and other illnesses [59].

Several biological, chemical or physical measures are taken worldwide to mitigate these HAB events. The most popular and effective action is modified clay (MC). By using inorganic and organic substances clay surface is reformed and used to remove the blooms. MC does not damage the water quality and can decrease the eutrophication by absorbing nutrients. Furthermore, MC can quickly reduce algal toxins with a faster degradation rate without affecting other marine organisms [60]. Biological control measures like using lactic acid bacteria and other marine bacteria (e.g. Paracoccus spp.) also effectively reduce HAB toxin [61]. Macroalgae cultivation is another potent way to control HAB events. A study showed macroalgae *Saccharina latissima*, *Chondrus crispus*, and *Ulva* spp. can hinder the growth and toxin production of *Alexandrium catenella* in aquaculture settings [62].

Besides these control measures, early risk assessment for eutrophication around the fish farming areas may help the related authorities to take precautionary measures. Climate change risk maps also can play a vital role in predicting upcoming HAB events in risk areas [63]. To further minimise economic loss and emotional stress, income diversification and skill development are highly recommended [64].
