Current status, trends, and future prospects for combining salinity tolerant tilapia and shrimp farming in Indonesia.

Aquaculture plays a key role in Indonesian seafood production and food security. The most valuable species in Indonesian aquaculture is shrimp, which has been widely farmed since the early 1980s. Beginning in the 1990s, recurrent farm failures and increasing production losses caused by disease outbreaks have hampered the growth of shrimp production. Many small-scale shrimp farmers face severe financial challenges and are looking for alternative crops to supplement their livelihoods. In recent years, many farmers have adopted rotational cropping and polyculture systems as a sanitary practice to reduce disease outbreaks. One promising strategy is to add tilapia as a second species on existing shrimp farms. Few studies have investigated the economic potential for using tilapia in rotational cropping or co-culture systems with shrimp, especially in the context of high spatial and temporal variability that can reduce tilapia growth rate in saline coastal shrimp ponds. We conducted a survey to acquire information on current tilapia production covering 17 sites in four provinces of Java (Banten, West Java, Central Java and East Java). This paper presents an analysis on the extent to which and how tilapia has been incorporated into traditional shrimp farming systems, and its economic implications based on the survey data. We selected a total of 224 representative shrimp-tilapia farmers in consultation with the Extension and Community Empowerment Centre of Marine and Fisheries, Ministry of Marine Affairs and Fisheries (MMAF), and interviewed them in small focus groups from every site. Local fisheries extension officers guided the interviews. Our results indicate that a majority of small-scale farmers in all four provinces have low income status. To sustain their production levels, farmers have developed novel rotational and co-culture farming systems. The farmers' income status influenced their decisions to adopt specific farming systems. The poly-rotational farming system, which is farming shrimp and tilapia in the same ponds during the rainy season followed by farming only shrimp in dry season provided the highest farm gross profit. Higher income status farmers have more access to high quality feed, pond lining materials, and aeration systems, which resulted a higher farm gross profit across all four farming systems. • We investigated the characteristics of small-scale shrimp tilapia farmers. • The farmers developed four farming systems to adopt tilapia on existing shrimp farms. • Farmers' experiences of farming failures in the past drove decision to farming system they use. • Farmers' income status drives farm inputs and farming systems applied. • The poly-rotational system is the most profitable farming system in small scale shrimp farms. [ABSTRACT FROM AUTHOR]