Review: Comparative Environmental Impacts and Development Benefits of Coastal Aquaculture in Three Tropical Countries: Madagascar, Tanzania and Indonesia

Aquaculture is still in early development in Madagascar and Tanzania, while in Indonesia aquaculture has a long history. In Madagascar villages are farming seaweed and sea cucumbers, as part of small-scale community-based aquaculture (CBA). They are following a contractual model between a private farming company and each farmer. Local nongovernmental organizations (NGOs) and public institutions in Madagascar jointly try to reverse the trend of ongoing anthropogenic coastal degradation. In Tanzania, the culture of red seaweeds is established since more than 30 years. Declining productions are attributed to climate change. While shrimp farming still involves, to some extent, clearing of mangroves in Tanzania, seaweed culture has only mild impact on coastal ecosystems. Farming areas provide shelter and habitat for juvenile fish, crabs and other organisms. Therefore, NGOs ask for support for improving culture methods. Problems and shortcomings in Indonesia such as new aquaculture areas, pollutants, upcoming diseases, insufficient broodstock and fry supply, as well as lack of technology and manpower were clearly identified. In order to secure and increase the aquaculture production, the government issued national policies and established training and broodstock-centres all over the country. Overall conclusions include that the CBA in Madagascar is a success story, also as a template for other coastal regions and countries. In Tanzania adoption of the CBA model for co-culture could be the future. In Indonesia, due to very long coastlines and complicated legislation, IMTA seems to be particularly suitable, as successfully tested in model regions.