Program

This presentation first reviews the recent success in bycatch management and reduction of discards in global fisheries. There are major global concerns that the combined effect of failing to effectively manage bycatch is threatening the long-term sustainability of fisheries and the maintenance of biodiversity, and is also contributing to food insecurity, thus affecting the livelihoods on those dependent on fish resources. Bycatch may consist of a large number of species which are often small in size and difficult to be utilized. Bycatch may also include juvenile fish. In many cases the bycatch is discarded. Discards represent inefficiency and waste, and should be minimized. There are a large number of examples where bycatch and discards have been significantly reduced by fishing technological solutions.
The bycatch problem also includes the entanglement of endangered, threatened and protected (ETP) species. For these critical species the entanglement in fishing gear is a major global threat. There have been significant global efforts to find practical solutions and best practices that would help to reduce the bycatch mortality of these species. This is one potential area where fishing technology research can produce practical new solutions. Furthermore, development of alternative capture technologies for fisheries where gear modifications are not adequate in bycatch reduction is a potentially important future area for fishing technologists. The challenges are significant but there are some success stories and more can be done. Maintaining practicality and efficiency are the key requirements.
There is a large number of projects going on around the world where the goal is to develop low impact and fuel efficient (LIFE) fishing gears and practices. One interesting example is the development of alternative captures methods for shrimp. The major part of the global shrimp catch is taken by trawl gears and there is a growing public resistance for this capture method because it is believed to cause major ecosystem damage. In some countries shrimp trawling has been completely banned. Extensive research and new technological innovations are needed to find solutions.
At the same time more research work is needed to understand how trawling and other forms of towed bottom fishing gears interact with marine seabed habitats and their biota. Recent international collaboration has brought together global datasets on the spatial distribution of trawl fishing activities and the impact of trawling on marine ecosystems and productivity. This information is used to understand the extent and consequence of trawling on a global scale and on a regional basis. The ultimate goal is to identify a range of suitable “best practices” for trawling and determine the consequences of adoption of these practices on biota, sustainable food production and ecosystem services. Furthermore, fishing industry has to reduce the overall fuel consumption to minimize the costs of operations and the emission of greenhouse gases. Fishing vessel energy audits can help to identify a variety of fuel-saving options and payback periods, and allow critical questions of the fishing operation to be asked. Nonetheless, audit protocols are still poorly established and more work is needed. The low-cost fuel saving options may include hull cleaning, fuel flow meters, improved trip planning, raised awareness and handling changes.
There are growing global concerns about environmental impacts of abandoned, lost or otherwise discarded fishing gear (ALDFG). ALDFG is perhaps the most dangerous part of marine litter because lost fishing gear are causing entanglement of marine species and may damage the habitats. Appropriate capture technologies and best practices allow to reduce ALDFG and ghost fishing. In addition, proper gear marking systems would contribute in the reduction of ALDFG and would also facilitate easier recovery of lost gear.
There are many more interesting areas where fishing technology has taken a critical role and will take also in the future. These area include the use of underwater light in improving the selectivity and efficiency of fishing gear. The capture of fish alive and in good quality is another important field that is growing. Finally, our understanding how to manage a change and how to collaborate with the fishing sector has significantly improved, and as a consequence, many ideas and developments by fishing technologists are adopted and further improved by the industry.

Hippoid crabs fishery is a common artisanal fishery in some coast of southern Java, Indonesia. In fishery management point of view, the biological information of the crab is needed to ensure its sustainable use. This study was aimed to reveal the diversity of the crabs, abundance and its standing biomass. The crabs were collected monthly at sandy coast of Cilacap in June 2013 to May 2014, and in sandy coast of Kebumen District in March 2012 to February 2013. The results showed that in both sites three species were discovered, namely Emerita emeritus, Hippa adactyla, and Albunea symmysta. E. emerita was the greatest composition percentage, 70.5-75.3%; followed by H. adactyla 22.5-24.7%; and A. symmysta 2.2-4.8%. In terms of sex, female crabs dominated the composition, i.e. 78.2-92.8%. The average abundance of E. emeritus were also the highest in Cilacap and Kebumen coasts, namely 5 and 34 ind/100 m2, respectively. In general, the abundance of the crab in Kebumen coast was higher than that in Cilacap coast. The standing biomass of E. emeritus fluctuated between 82 and 497 kg on Kebumen coast and between 1,462 and 3,560 kg on Cilacap coast. While standing biomass of H. adactyla fluctuated between 2 and 133 kg and between 234 and 1,701 kg on Kebumen and Cilacap coasts, respectively. The economic value potential of the crab as fishery resources is discussed.

Abundance and biomass distribution are basic information related to resources allocation for fisheries management. We investigated spatial-temporal on relative abundance and biomass of the blue swimming crab (Portunus pelagicus) that caught by bottom gill-net from March 2012 to February 2013 in East Lampung coastal waters of Indonesia. The study area was divided into three stratifications: S1 (water depth of <5 m and <4 nautical miles from the shore line), S2 (water depth of 5−10 m and 4−10 nautical miles from the shore line), and S3 (offshore). Four sub areas (A1−A4) in each stratum were identified based on the morphological characteristics of shore and coastal land coverage. Thus, the sampling areas were S1A1 to S3A4. No data at S3A1−S3A4 during August−November 2012 and temporal analysis of abundance and biomass was conducted for S1−S2 and S1−S3 within 12 and eight months data, respectively. Result showed that there was no significant different of abundance at S1−S2 (P>0.05), but it was significant different by observed month (P<0.05). Biomass was higher at S2 than S1. Relative abundance and biomass at S1−S3 during 8 months were significantly different (P<0.05) as well as by observed month (P<0.05) and biomass was higher at S3 compared to S2 and S1. Abundance and biomass were high during December−May (west monsoon) and the highest biomass in March. Those spatial-temporal variations might be related to crab life cycle, behaviour and habitat preferences. Based on abundance and biomass, the waters at S2 are potential year-round fishing grounds, and at S3 are potential for eight-months.

This study determined the effects of net height on the capture performance of crab entangling nets. Fishing trials were conducted using nets with the following net heights:1) 12 meshes down (MD), 2) 24 MD and 3) 50 MD. A total of 1,290 individuals comprising of 87 species belonging to 53 families were caught. One-way ANOVA showed that net height significantly affects various catch parameters such as catch per unit effort (CPUE) of the total and target catch, amount of non-target catch, sizes and species richness. The use of appropriate net height is a potential technical measure for a selective but still efficient crab entangling net fishery. Lower net height significantly reduced non-target catch up to 70%. While lower nets decreased the CPUE of target catch such as Portunus pelagicus and Charybdis feriatus up to 65% in 12 MD, catch in 24 MD was not significantly different with that in 50 MD. The use of 24 MD also resulted to capture larger-sized Portunus pelagicus. Catch species richness decreased up to 58% in lower nets. These results are useful to fisheries managers and government institutions to develop or improve existing regulations towards a sustainable crab fishery particularly blue swimming crabs.

Segara Anakan Lagoon is located in the south of Java Island, in the border area between West Java and Central Java Provinces, Indonesia. The total area of Segara Anakan is approximately 24,000 hectares, which includes waters, mangrove forests, and muddy lands that have high fishery potentials. This study aims to analyze the distribution of fish in the area and relate it to the aquatic environmental condition. Fish sampling and aquatic environmental condition observation had been conducted for 9 months from March to November 2016, at 6 stations in the lagoon distributed at the location near the sea and near the river ecosystems. The fish samples were caught using gill net, cast-nets and intertidal fyke-net. The aquatic environmental parameters observed were temperature, transparency, depth, total suspended solid (TSS), total dissolved solid (TDS), pH, salinity, dissolved oxygen (DO), nitrate, nitrite, and orthophosphate. The relationship between number of fish species and their aquatic environmental condition was analyzed using PCA (Principle Component Analysis). Based on the study, 85 species of fish distributed at Station 1 (42 species), Station 2 (40 species), Station 3 (18 species), Station 4 (36 species), Station 5 (34 species) and Station 6 (37 species) were found. The aquatic environmental conditions of the lagoon included temperature of 25-32.4 oC, transparency of 0.05-0.68 m, depth of 1.3-10.1 m, TDS of 0.214-25,298 mg/l, TSS of 0.0021-1,028 mg/l, salinity of 0 - 36 ppm, pH of 5 - 8, DO of 2.5– 7.1 mg/l, nitrate of 0.017 - 0.685mg/l, nitrite of 0.001 - 0.294mg/l and orthophosphate of 0.001- 0.468 mg/l. Based on the PCA analysis, there is a positive correlation (r>0,75) between the number of fish species and aquatic salinity, pH, and TDS. It shows that stations near the sea have more number of species than stations near the river.

The purpose of this study was to investigate the distribution pattern of larval fish assemblages (LFA) and how hydrographic conditions (temperature, salinity, superficial chlorophyll a, currents) contribute to determining the community structure, in terms of species composition, abundance and spatial distribution of fish larvae, in a wide coastal area of the Savu Sea Marine National Park, Indonesia. Sampling was conducted at 36 stations along the inshore of Timor, Rote, Sumba and Flores Islands. Larvae were collected by oblique tows of a larval net during an ichthyoplanktonic survey in November 2016. In total, 1037 larval fishes were collected representing 42 families and 70 species. The Nemipteridae, Scombridae, Pomacentridae, Engraulidae and Lutjanidae were the dominant fish families. The distribution patterns in abundance and species assemblages were closely linked with the oceanographic conditions and well matched with abundance of phyto-and zooplankton. The results of this study could have implications for the management of fishery resources in the Lesser Sunda Region because the investigated area has already been identified as a nursery ground and natural habitat for many commercially important fishes.