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Traditional farmers of milkfish and shrimp use 80% of Indonesia's shrimp production area, but produce only 10% of its shrimp. A coastal protection project funded a 16-day aquaculture field school (AFS) in order to train 277 farmers in Low External Input Sustainable Aquaculture (LEISA). Its cost was 1,060 USD per farmer. In 2017 and 2018, the project monitoring database completed records of yields and practices of 125 participants and monitored finances and water quality in a 10% sample. LEISA was adopted by 85% of the 125 participants. The two annual datasets of the sample were merged and trimmed from three outliers; this was done before statistical analysis. Compared to the baseline, LEISA adopters among the 125 tripled their shrimp' yields. Within the sample, the milkfish yields of adopters and non-adopters were about identical. Sampled adopters significantly increased their gross margin by 927 USD ha−1 year−1 due to three- and fivefold yield increases for milkfish and shrimp compared to that of the baseline. The rate of return was 1.3 for the 277 participants and 1.8 for the sample, indicating a payback time of <1 year. Enriching the farmers' skills with AFS can double Indonesian milkfish production and increase its shrimp production by 25–50%.

Gender equality has been a political issue in view of human rights and welfare since several decades. Therefore, many countries have developed Gender Action Plans (GAPs) that support equal access of both sexes to education, employment and finance. Two workshops on GAPs in aquaculture and a literature review brought about the question: what's missing in Asian sectoral GAPs. Not all reviewed Asian countries have GAPs for fishery/ aquaculture, but all encountered constraints to achieve their goals regarding equal access for women. Women's contribution in aquaculture tends to go beyond the traditional gender divide. For example, women may lead in the area of production because they can combine aquaculture with their homebound tasks and own vertically integrated companies. However, skewed perceptions on the role, status and perception of women and men, more so in strong than weak patriarchies (the former accept the subservient role, while the latter exercise the dominant role) limit women's access to training opportunities on new aquaculture technologies. Women are also left out in policy- and decision-making processes; and in the value chain, women receive lower wages than men. Their role is underestimated by lack of disaggregated data, as reflected in post-disaster interventions and industrial development programs. To be effective sectoral GAPs, based on disaggregated data, should have budgets, plans and target indicators for which leaders could be held accountable. These GAPs, however, can't address the required radical change in attitude toward women; unless deliberately planned educational media campaigns are embedded into the national GAPs.

The use of serious games in the governance of natural resources and the environment is progressively increasing and includes games used for research and data collection, teaching and training, and fostering a change of practices. However, this diversity remains underexplored and underreported. In view of a growing interest in the use of serious games in natural resource and environmental governance, the absence of discussions about how differences in intended use and delivery influence the performance, assessment, and outcomes of games is problematic. Here we present an inventory, and a description, of such different uses then, by focusing on serious games used as interventions, we discuss when, and how, games could be used to generate learning and social learning. To that end we use a narrative review of selected literature, and insight from research on social learning, to develop an inventory of game use, and within that inventory we conceptualize the use of serious games as a social learning intervention. Also, by means of an illustrative case of a serious game (developed as part of the Assessing the Learning Effects of Games on Attitude of Stakeholders toward Sustainable Shrimp Farming – ALEGAMS research project) we reflect on a few key aspects of game use. We suggest that developing a serious game needs several iterations and, although the learning outcomes can be assessed, the impact of games aiming at changes in current practice and policy will likely fall beyond the timespan of usual project periods. This is something future research should consider as it has implications for the research design and methodology.

Shrimp farming in Demak, Indonesia is often practiced in silvo-aquaculture systems in which mangrove trees are planted on pond bunds. As such, mangrove leaves and its substrates may have impact on penaeid shrimp production. In this area, mangrove re-growth proceeded with Avicennia marina while planting is mostly done with Rhizophora apiculata. We compared the effects of decomposing fresh leaves of A. marina and R. apiculata on water quality and on the performance of Penaeus monodon postlarvae (PL). A hundred of PL21 (postlarvae aged 21 days with weight of 0.28 g) were stocked in each of 30 aerated tanks containing 800 liters of brackish water (salinity of 21 ppt) for 37 days. Five treatments with three replicates for each mangrove species were assigned by adding into the tanks of 0.125, 0.25, and 0.5 g L-1 of air-dried leave, 0.125 of g L-1 minced leave and 0.125 g L-1 of leachate of minced leaves. The PLs were fed 3 times daily with pellets at 10 % of initial total body weight. Water quality parameters were recorded daily. Tannin, H2S and NH3-N concentrations were measured every ten days. Prawn’s body weight (BW) was measured and specific growth rate (SGR, % day-1) and survival rate (SR, %) were calculated after the end of experiment. Results were analyzed with ANOVA and Pearson’s correlation. The results showed that tannin in decomposing mangrove leaf litter up to a concentration of 0.5 mg g-1 did not have a significant effect on water quality and on the growth and survival of P. monodon PL. However, increasing leaf litter concentrations showed an increase in NH3-N concentration due to organic matter degradation. The accumulation of NH3-N may have caused the slow growth of shrimp PL in A. marina treatment. Shrimp PL in leaf litter leachates treatment has a higher growth rate than those PL in regular leaf litter in relation to nutritional value. Survival and growth varied from 62 ±14 to 70 ± 8% and 3.1±2.1 to 5.5±1.2% day-1, respectively. Although decomposing mangr

The technical efficiency of randomly sampled pangasius farms in the Mekong Delta of Vietnam was estimated using data envelopment analysis, and factors affecting technical and scale efficiency were examined with bootstrap truncated regression. The mean technical efficiency score assuming variable returns to scale was 0.84. The technical efficiency of downstream farmers was higher due to lower energy costs and stocking once a year. Most of the up‐ and midstream farms needed to pump water and stocked at least three times in 2 yr. Regression analysis showed a positive effect on technical efficiency of the farmers' education level and having experienced climate change impact through flooding or salinity intrusion in the past. Farms affected by salinity intrusion had a lower scale efficiency as they reduce stocking frequency and rate. In general, reducing fish mortality and the cost of inputs, increasing scale of operation, and being trained, using appropriate methods, in management strategies may improve technical efficiency.

Vietnamese pangasius farming needs to produce efficiently to compete in world markets. This study investigates the input- and output-specific technical inefficiency of Vietnamese pangasius farmers. First, we used a Russell-type (input–output) directional distance function to estimate the input- and output-specific technical inefficiency. Second, we applied a bootstrap truncated regression to analyze the factors influencing these technical inefficiencies. Results show that the main challenges for enhancing the performance of Vietnamese pangasius production are inadequate use of capital assets (inefficiency of 42%) and improper methods to achieve higher fish yield (inefficiency of 30%). Input-specific technical inefficiency (pond area and feed) is negatively associated with the experience and education level of pangasius farmers. Location of the farm in a saltwater intrusion area is positively associated with the inefficiency of producing fish. Outcomes of this study are useful to identify successful strategies to minimize the use of inputs while simultaneously maximizing fish production.

The neonicotinoid insecticide imidacloprid is used in Bangladesh for a variety of crop protection purposes. Imidacloprid may contaminate aquatic ecosystems via spray drift, surface runoff and ground water leaching. The present study aimed at assessing the fate and effects of imidacloprid on structural (phytoplankton, zooplankton, macroinvertebrates and periphyton) and functional (organic matter decomposition) endpoints of freshwater, sub-tropical ecosystems in Bangladesh. Imidacloprid was applied weekly to 16 freshwater microcosms (PVC tanks containing 400 L de-chlorinated tap water) at nominal concentrations of 0, 30, 300, 3000 ng/L over a period of 4 weeks. Results indicated that imidacloprid concentrations from the microcosm water column declined rapidly. Univariate and multivariate analysis showed significant effects of imidacloprid on the zooplankton and macroinvertebrate community, some individual phytoplankton taxa, and water quality variables (i.e. DO, alkalinity, ammonia and nitrate), with Cloeon sp., Diaptomus sp. and Keratella sp. being the most affected species, i.e. showing lower abundance values in all treatments compared to the control. The observed high sensitivity of Cloeon sp. and Diaptomus sp. was confirmed by the results of single species tests. No significant effects were observed on the species composition of the phytoplankton, periphyton biomass and organic matter decomposition for any of the sampling days. Our study indicates that (sub-)tropical aquatic ecosystems can be much more sensitive to imidacloprid compared to temperate ones.

Gracilaria verrucosa is one of the Rhodophyta, it has an economic value and major aquaculture commodity in Indonesia which the production had increased between 2010 and 2014. Agar is one of the hydrocolloid extracts from Gracilaria, which the quality depends on the strain, cultivation methods and the water quality. This research compares three cultivation methods (broadcast, off-bottom and long-line) and two seedling types (local versus tissue cultured). After 60 days of cultivation, the Specific Growth Rates (SGRs), the agar content and gel strength were determined. The SGR (%d-1) of the local seedlings was higher than that of the tissue-cultured for all three culture methods: 1.2-1.3 and 0.5-1.1, respectively, probably due to adaptation problems. Overall, broadcasting resulted in a significantly higher agar content (9.6%) compared to off-bottom (6%) and long-line (3.2%), because of the low amount of light compared to photosynthesis, translating to less cell walls and more accumulation of carrageenan farther from the water surface. The gel strength of tissue-cultured seedlings in broadcast and off-bottom was significantly higher than that from long-line (505 compared to 201 g cm-2). The choice of seedlings and culture method may depend on the market price criteria and final use of the seaweed.

Pangasius production in Vietnam is widely known as a success story in aquaculture, the fastest growing global food system because of its tremendous expansion by volume, value and the number of international markets to which Pangasius has been exported in recent years. While certification schemes are becoming significant features of international fish trade and marketing, an increasing number of Pangasius producers have followed at least one of the certification schemes recognised by international markets to incorporate environmental and social sustainability practices in aquaculture, typically the Pangasius Aquaculture Dialogue (PAD) scheme certified by the Aquaculture Stewardship Council (ASC). An assessment of the environmental benefit of applying certification schemes on Pangasius production, however, is still needed. This article compared the environmental impact of ASC-certified versus non-ASC certified intensive Pangasius aquaculture, using a statistically supported LCA. We focused on both resource-related (water, land and total resources) and emissions-related (global warming, acidification, freshwater and marine eutrophication) categories. The ASC certification scheme was shown to be a good approach for determining adequate environmental sustainability, especially concerning emissions related categories, in Pangasius production. However, the non-ASC certified farms, due to the large spread, the impact (e.g., water resources and freshwater eutrophication) was possibly lower for a certain farm. However, this result was not generally prominent. Further improvements in intensive Pangasius production to inspire certification schemes are proposed, e.g., making the implementation of certification schemes more affordable, well-oriented and facilitated; reducing consumed feed amounts and of the incorporated share in fishmeal, especially domestic fishmeal, etc. However, their implementation should be vetted with key stakeholders to assess their feasibility.

This study investigated the perceptions on and adaptations to climate change impacts of 235 pangasius farmers in the Mekong Delta, Vietnam. Data were collected using semi-structured household surveys in six provinces, from three regions along the Mekong river branches. A Chi-Square test was used to determine the association between variables, and a logit regression model was employed to identify factors correlated with farmer’s perception and adaptation. Less than half of respondents were concerned about climate change and sought suitable adaptation measures to alleviate its impacts. Improving information on climate change and introducing early warning systems could improve the adaptive capacity of pangasius farmers, in particularly for those farmers, who were not concerned yet. Farmers relied strongly on technical support from government agencies, but farmers in the coastal provinces did not express the need for training by these institutions. This contrasting result requires further assessment of the effectiveness of adaptation measures such as breeding salinity tolerant pangasius.