The investigation is aimed to know the relationship between chlorophyll-a (chl-a) concentration and the abundance of Oily sardine (Sardinella lemuru), in Bali Strait. A time series of monthly mean chl-a data derived from Ocean Color Thermal Scanner (OCTS) sensor and Sea-viewing Wide Field-of View Sensor (SeaWiFS) during 1997-1999 are used in this study. Monthly Sardinella lemuru catch during 1997-1999 are obtained from fish landing data. The abundance of Sardinella lemuru is determined from acoustic data conducted in Bali Strait in September 1998 and May 1999. The result shows that the fluctuation of chlorophyll-a concentration in Bali Strait is influenced by monsoon and global climate change phenomena such as Dipole Mode (DM) event. During southeast Monsoon the upwelling process occurred around Bali Strait, so that the chl-a concentration is increased and during DM event occurred positive anomaly of chl-a concentration. The catch of Sardinella lemuru in Bali Strait is fluctuated during 1997-1999. The correlation between chl-a concentration and lemuru catch is positive and significant with certain time lag. Key words: Chlorophyll-a, Sardinella lemuru, Bali Strait, Satellite imagery

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This paper aims to describe the Fish Aggregating Devices (FADs) fisheries in Indonesia and its relation to sustainable fisheries management. On tuna fishing, FADs are widely used as a tool to attract fish. FADs uncontrolled development is feared to have an impact on the sustainability of fish resources. We found that most of the fish caught around FADs are still juvenile. Deployment FADs can also interfere with the swimming pattern of tuna resources. This is negatively affecting the sustainability of tuna resources. However, from the social and economic aspects, FADs provide significant benefits for fishing communities. The Government has imposed regulations on FADs but not yet implemented. The objective of SDG's in the management of tuna fisheries associated with FADs can be implemented through the application of RFMO regulations. Findings from this paper can be used for policy recommendations for the management of sustainable FADsfisheries. , 0 (2018) E3S Web of Conferences

Sikka Regency, Nusa Tenggara Timur is one of the key landing places for tuna in Indonesia’s archipelagic waters (IAW), which was selected for pilot scale application of EAFM. This study was aimed to identify some best practices of the EAFM application from pole and line fishery based in Sikka Regency. Pole and line data were collected by the observer and port sampling programs, data from handline fishery collected from other areas within the IAW was also investigated. Furthermore, for broader comparison purposes, trends from purse seine fishery operated in other areas within the IAW were also used. Data from pole and line fishery in Sikka Regency were analyzed to obtain length distribution by gear. Stakeholder consultative meetings were conducted to investigate some key issues and possible improvements for the fishery. Skipjack was the most predominant species caught by pole and line and purse seine (> 60%) but mostly immature fish. All yellowfin tuna caught by pole and line and purse seine was immature. It is recommended to reduce small-sized yellowfin catch and to maximize the economic benefit to local fishers. In addition, improvement of FAD management implementation, monitoring, and law enforcement are required reflected best practice of EAFM.

Context. The growing demand for global food security has resulted in rising fishing intensity, sometimes leading to overexploitation of fish resources, including tuna. Increasingly, fishers are using anchored fish aggregating devices (aFADs) to improve efficiencies and reduce costs. Aims. To identify locations and use patterns of FADs and characterise aFAD usage in Indonesia and beyond. Methods. We identified general patterns of aFAD usage by tuna purse-seine, pole and line, hand-line and troll-line vessels operating in Indonesian waters through reviewing relevant literature and focal-group discussions. Key results. aFADs usage can be characterised by gear type and fishing strategy; vessel behaviour; equipment and spare parts for aFADs installation; association with light; trip duration, catch per unit effort (CPUE), ratio of live bait to catch, fuel consumption; existence of aFAD floats on board vessels and by-catch composition. Conclusions. aFAD usage has been widely adopted by both industrial and small-scale tuna fishers to efficiency. However, this efficiency comes at the cost of significant increases in catches of juveniles and non-target species, which raises sustainability concerns for Indonesian officials. Implications. Ultimately, quantifying the numbers, types and locations of aFADs is key to fisheries management to avoid overfishing, overcrowding and limit by-catch and fishing-associated waste.