Wild spat collection has been described as a source of pollution because of the numerous particularly fragile and brittle shade-mesh plastic collectors used locally and often mismanaged when no longer usable. In French Polynesia, black-lip pearl oyster (Pinctada margaritifera) farming is no exception. While threatened by this marine plastic litter, the aquaculture industries also represent one of its major sources. Plastic waste in the oceans is a growing concern due to its size diversity, its ubiquitous nature and its impact on both marine organisms and ecosystems. Nevertheless, achieving profitable production and a stronger commitment within local communities, as well as developing effective mariculture governance through support mechanisms and clear strategies to boost the sector at the national level, are essential for sustainable mariculture development in Zanzibar. We conclude that aquaculture has great potential to evolve due to high environmental capacity. This situation does not encourage engagement in aquaculture and thus such activities are outcompeted by other already established sectors (e.g. In addition, new aquaculture initiatives are often dominated by donor-driven projects instead of local entrepreneurships. At the same time, there is a lack of sufficient management and monitoring systems, while there are no formal regulations or clear strategies to boost aquaculture at the national level. Common constraints among these activities are economic limitations, lack of technical infrastructure and skills, small and irregular production, and limited trade and market availabilities. Other types of aquaculture activities such as fish farming, mud crab fattening, half-pearl farming, sea cucumber farming and sponge and coral cultures are under development with limited production or in experimental stages. However, seaweed farming constraints such as frequent seaweed die-offs, as well as economic and institutional constraints inhibit its development. This activity is dominated by women and became widespread in the early 1990s as a small but regular source of income. Despite the immense potential of aquaculture for food and livelihoods, only seaweed farming has so far established into commercial-scale production. This study provides an overview of the multi-sectoral coastal aquaculture development in Zanzibar (Tanzania) over the last thirty years based on empirical evidence from interviews, field observations, policy reports and literature reviews. Thus, the use of the low‐cost, simple collectors using coconut fibre could be a new conservation measure for endangered holothurian resources, and are manageable by local communities. These results show that WJC is a viable option for tropical holothurians. Collection in the inner bay areas was successful, whereas rough weather physically damaged the collectors in areas open to the ocean. The total yield corresponded to approximately 1% of the total abundance of the ambient holothurian community, demonstrating potential for restocking, considering the ease of the extension and repetition of the trials. It is characteristic of tropical WJC that diverse species can be collected simultaneously (including rare, non‐culturable species), which is advantageous over hatchery production for restocking purposes. horrens, stonefish (Actinopyga lecanora), kingfish (Synapta maculata), and five unidentified species. A total of 14 juvenile holothurians were collected, including Stichopus cf. The newly designed simple collector comprised between two and four net bags filled with coconut fibre, which were tied to a rope vertically moored between a concrete block anchor and polyethylene terephthalate (PET) bottle floats. Second, 25 collectors were installed for 3 months in the field in Nggela, Solomon Islands. The results showed that the coconut fibre and mesh bags collected more settling larvae than the oyster shells. First, hatchery‐produced larvae of peanutfish (Stichopus horrens) before settlement were introduced in a tank in which bundles of coconut fibre, rolled mesh bags, and oyster shells were suspended to identify the most suitable settlement material. This study, for the first time, tested the applicability of WJC for tropical sea cucumbers. Wild juvenile collection (WJC) from settling larvae has been reported for two temperate holothurians (Apostichopus japonicus and Apostichopus californicus), mainly for the objective of restocking, but its applicability to tropical holothurians is unknown.
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